package chart
import (
"fmt"
"math"
util "github.com/wcharczuk/go-chart/util"
)
// Interface Assertions.
var (
_ Series = (*AnnotationSeries)(nil)
)
// AnnotationSeries is a series of labels on the chart.
type AnnotationSeries struct {
Name string
Style Style
YAxis YAxisType
Annotations []Value2
}
// GetName returns the name of the time series.
func (as AnnotationSeries) GetName() string {
return as.Name
}
// GetStyle returns the line style.
func (as AnnotationSeries) GetStyle() Style {
return as.Style
}
// GetYAxis returns which YAxis the series draws on.
func (as AnnotationSeries) GetYAxis() YAxisType {
return as.YAxis
}
func (as AnnotationSeries) annotationStyleDefaults(defaults Style) Style {
return Style{
FontColor: DefaultTextColor,
Font: defaults.Font,
FillColor: DefaultAnnotationFillColor,
FontSize: DefaultAnnotationFontSize,
StrokeColor: defaults.StrokeColor,
StrokeWidth: defaults.StrokeWidth,
Padding: DefaultAnnotationPadding,
}
}
// Measure returns a bounds box of the series.
func (as AnnotationSeries) Measure(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) Box {
box := Box{
Top: math.MaxInt32,
Left: math.MaxInt32,
Right: 0,
Bottom: 0,
}
if as.Style.IsZero() || as.Style.Show {
seriesStyle := as.Style.InheritFrom(as.annotationStyleDefaults(defaults))
for _, a := range as.Annotations {
style := a.Style.InheritFrom(seriesStyle)
lx := canvasBox.Left + xrange.Translate(a.XValue)
ly := canvasBox.Bottom - yrange.Translate(a.YValue)
ab := Draw.MeasureAnnotation(r, canvasBox, style, lx, ly, a.Label)
box.Top = util.Math.MinInt(box.Top, ab.Top)
box.Left = util.Math.MinInt(box.Left, ab.Left)
box.Right = util.Math.MaxInt(box.Right, ab.Right)
box.Bottom = util.Math.MaxInt(box.Bottom, ab.Bottom)
}
}
return box
}
// Render draws the series.
func (as AnnotationSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) {
if as.Style.IsZero() || as.Style.Show {
seriesStyle := as.Style.InheritFrom(as.annotationStyleDefaults(defaults))
for _, a := range as.Annotations {
style := a.Style.InheritFrom(seriesStyle)
lx := canvasBox.Left + xrange.Translate(a.XValue)
ly := canvasBox.Bottom - yrange.Translate(a.YValue)
Draw.Annotation(r, canvasBox, style, lx, ly, a.Label)
}
}
}
// Validate validates the series.
func (as AnnotationSeries) Validate() error {
if len(as.Annotations) == 0 {
return fmt.Errorf("annotation series requires annotations to be set and not empty")
}
return nil
}
package chart
import (
"errors"
"fmt"
"io"
"math"
"github.com/golang/freetype/truetype"
util "github.com/wcharczuk/go-chart/util"
)
// BarChart is a chart that draws bars on a range.
type BarChart struct {
Title string
TitleStyle Style
ColorPalette ColorPalette
Width int
Height int
DPI float64
BarWidth int
Background Style
Canvas Style
XAxis Style
YAxis YAxis
BarSpacing int
UseBaseValue bool
BaseValue float64
Font *truetype.Font
defaultFont *truetype.Font
Bars []Value
Elements []Renderable
}
// GetDPI returns the dpi for the chart.
func (bc BarChart) GetDPI() float64 {
if bc.DPI == 0 {
return DefaultDPI
}
return bc.DPI
}
// GetFont returns the text font.
func (bc BarChart) GetFont() *truetype.Font {
if bc.Font == nil {
return bc.defaultFont
}
return bc.Font
}
// GetWidth returns the chart width or the default value.
func (bc BarChart) GetWidth() int {
if bc.Width == 0 {
return DefaultChartWidth
}
return bc.Width
}
// GetHeight returns the chart height or the default value.
func (bc BarChart) GetHeight() int {
if bc.Height == 0 {
return DefaultChartHeight
}
return bc.Height
}
// GetBarSpacing returns the spacing between bars.
func (bc BarChart) GetBarSpacing() int {
if bc.BarSpacing == 0 {
return DefaultBarSpacing
}
return bc.BarSpacing
}
// GetBarWidth returns the default bar width.
func (bc BarChart) GetBarWidth() int {
if bc.BarWidth == 0 {
return DefaultBarWidth
}
return bc.BarWidth
}
// Render renders the chart with the given renderer to the given io.Writer.
func (bc BarChart) Render(rp RendererProvider, w io.Writer) error {
if len(bc.Bars) == 0 {
return errors.New("please provide at least one bar")
}
r, err := rp(bc.GetWidth(), bc.GetHeight())
if err != nil {
return err
}
if bc.Font == nil {
defaultFont, err := GetDefaultFont()
if err != nil {
return err
}
bc.defaultFont = defaultFont
}
r.SetDPI(bc.GetDPI())
bc.drawBackground(r)
var canvasBox Box
var yt []Tick
var yr Range
var yf ValueFormatter
canvasBox = bc.getDefaultCanvasBox()
yr = bc.getRanges()
if yr.GetMax()-yr.GetMin() == 0 {
return fmt.Errorf("invalid data range; cannot be zero")
}
yr = bc.setRangeDomains(canvasBox, yr)
yf = bc.getValueFormatters()
if bc.hasAxes() {
yt = bc.getAxesTicks(r, yr, yf)
canvasBox = bc.getAdjustedCanvasBox(r, canvasBox, yr, yt)
yr = bc.setRangeDomains(canvasBox, yr)
}
bc.drawCanvas(r, canvasBox)
bc.drawBars(r, canvasBox, yr)
bc.drawXAxis(r, canvasBox)
bc.drawYAxis(r, canvasBox, yr, yt)
bc.drawTitle(r)
for _, a := range bc.Elements {
a(r, canvasBox, bc.styleDefaultsElements())
}
return r.Save(w)
}
func (bc BarChart) drawCanvas(r Renderer, canvasBox Box) {
Draw.Box(r, canvasBox, bc.getCanvasStyle())
}
func (bc BarChart) getRanges() Range {
var yrange Range
if bc.YAxis.Range != nil && !bc.YAxis.Range.IsZero() {
yrange = bc.YAxis.Range
} else {
yrange = &ContinuousRange{}
}
if !yrange.IsZero() {
return yrange
}
if len(bc.YAxis.Ticks) > 0 {
tickMin, tickMax := math.MaxFloat64, -math.MaxFloat64
for _, t := range bc.YAxis.Ticks {
tickMin = math.Min(tickMin, t.Value)
tickMax = math.Max(tickMax, t.Value)
}
yrange.SetMin(tickMin)
yrange.SetMax(tickMax)
return yrange
}
min, max := math.MaxFloat64, -math.MaxFloat64
for _, b := range bc.Bars {
min = math.Min(b.Value, min)
max = math.Max(b.Value, max)
}
yrange.SetMin(min)
yrange.SetMax(max)
return yrange
}
func (bc BarChart) drawBackground(r Renderer) {
Draw.Box(r, Box{
Right: bc.GetWidth(),
Bottom: bc.GetHeight(),
}, bc.getBackgroundStyle())
}
func (bc BarChart) drawBars(r Renderer, canvasBox Box, yr Range) {
xoffset := canvasBox.Left
width, spacing, _ := bc.calculateScaledTotalWidth(canvasBox)
bs2 := spacing >> 1
var barBox Box
var bxl, bxr, by int
for index, bar := range bc.Bars {
bxl = xoffset + bs2
bxr = bxl + width
by = canvasBox.Bottom - yr.Translate(bar.Value)
if bc.UseBaseValue {
barBox = Box{
Top: by,
Left: bxl,
Right: bxr,
Bottom: canvasBox.Bottom - yr.Translate(bc.BaseValue),
}
} else {
barBox = Box{
Top: by,
Left: bxl,
Right: bxr,
Bottom: canvasBox.Bottom,
}
}
Draw.Box(r, barBox, bar.Style.InheritFrom(bc.styleDefaultsBar(index)))
xoffset += width + spacing
}
}
func (bc BarChart) drawXAxis(r Renderer, canvasBox Box) {
if bc.XAxis.Show {
axisStyle := bc.XAxis.InheritFrom(bc.styleDefaultsAxes())
axisStyle.WriteToRenderer(r)
width, spacing, _ := bc.calculateScaledTotalWidth(canvasBox)
r.MoveTo(canvasBox.Left, canvasBox.Bottom)
r.LineTo(canvasBox.Right, canvasBox.Bottom)
r.Stroke()
r.MoveTo(canvasBox.Left, canvasBox.Bottom)
r.LineTo(canvasBox.Left, canvasBox.Bottom+DefaultVerticalTickHeight)
r.Stroke()
cursor := canvasBox.Left
for index, bar := range bc.Bars {
barLabelBox := Box{
Top: canvasBox.Bottom + DefaultXAxisMargin,
Left: cursor,
Right: cursor + width + spacing,
Bottom: bc.GetHeight(),
}
if len(bar.Label) > 0 {
Draw.TextWithin(r, bar.Label, barLabelBox, axisStyle)
}
axisStyle.WriteToRenderer(r)
if index < len(bc.Bars)-1 {
r.MoveTo(barLabelBox.Right, canvasBox.Bottom)
r.LineTo(barLabelBox.Right, canvasBox.Bottom+DefaultVerticalTickHeight)
r.Stroke()
}
cursor += width + spacing
}
}
}
func (bc BarChart) drawYAxis(r Renderer, canvasBox Box, yr Range, ticks []Tick) {
if bc.YAxis.Style.Show {
axisStyle := bc.YAxis.Style.InheritFrom(bc.styleDefaultsAxes())
axisStyle.WriteToRenderer(r)
r.MoveTo(canvasBox.Right, canvasBox.Top)
r.LineTo(canvasBox.Right, canvasBox.Bottom)
r.Stroke()
r.MoveTo(canvasBox.Right, canvasBox.Bottom)
r.LineTo(canvasBox.Right+DefaultHorizontalTickWidth, canvasBox.Bottom)
r.Stroke()
var ty int
var tb Box
for _, t := range ticks {
ty = canvasBox.Bottom - yr.Translate(t.Value)
axisStyle.GetStrokeOptions().WriteToRenderer(r)
r.MoveTo(canvasBox.Right, ty)
r.LineTo(canvasBox.Right+DefaultHorizontalTickWidth, ty)
r.Stroke()
axisStyle.GetTextOptions().WriteToRenderer(r)
tb = r.MeasureText(t.Label)
Draw.Text(r, t.Label, canvasBox.Right+DefaultYAxisMargin+5, ty+(tb.Height()>>1), axisStyle)
}
}
}
func (bc BarChart) drawTitle(r Renderer) {
if len(bc.Title) > 0 && bc.TitleStyle.Show {
r.SetFont(bc.TitleStyle.GetFont(bc.GetFont()))
r.SetFontColor(bc.TitleStyle.GetFontColor(bc.GetColorPalette().TextColor()))
titleFontSize := bc.TitleStyle.GetFontSize(bc.getTitleFontSize())
r.SetFontSize(titleFontSize)
textBox := r.MeasureText(bc.Title)
textWidth := textBox.Width()
textHeight := textBox.Height()
titleX := (bc.GetWidth() >> 1) - (textWidth >> 1)
titleY := bc.TitleStyle.Padding.GetTop(DefaultTitleTop) + textHeight
r.Text(bc.Title, titleX, titleY)
}
}
func (bc BarChart) getCanvasStyle() Style {
return bc.Canvas.InheritFrom(bc.styleDefaultsCanvas())
}
func (bc BarChart) styleDefaultsCanvas() Style {
return Style{
FillColor: bc.GetColorPalette().CanvasColor(),
StrokeColor: bc.GetColorPalette().CanvasStrokeColor(),
StrokeWidth: DefaultCanvasStrokeWidth,
}
}
func (bc BarChart) hasAxes() bool {
return bc.YAxis.Style.Show
}
func (bc BarChart) setRangeDomains(canvasBox Box, yr Range) Range {
yr.SetDomain(canvasBox.Height())
return yr
}
func (bc BarChart) getDefaultCanvasBox() Box {
return bc.box()
}
func (bc BarChart) getValueFormatters() ValueFormatter {
if bc.YAxis.ValueFormatter != nil {
return bc.YAxis.ValueFormatter
}
return FloatValueFormatter
}
func (bc BarChart) getAxesTicks(r Renderer, yr Range, yf ValueFormatter) (yticks []Tick) {
if bc.YAxis.Style.Show {
yticks = bc.YAxis.GetTicks(r, yr, bc.styleDefaultsAxes(), yf)
}
return
}
func (bc BarChart) calculateEffectiveBarSpacing(canvasBox Box) int {
totalWithBaseSpacing := bc.calculateTotalBarWidth(bc.GetBarWidth(), bc.GetBarSpacing())
if totalWithBaseSpacing > canvasBox.Width() {
lessBarWidths := canvasBox.Width() - (len(bc.Bars) * bc.GetBarWidth())
if lessBarWidths > 0 {
return int(math.Ceil(float64(lessBarWidths) / float64(len(bc.Bars))))
}
return 0
}
return bc.GetBarSpacing()
}
func (bc BarChart) calculateEffectiveBarWidth(canvasBox Box, spacing int) int {
totalWithBaseWidth := bc.calculateTotalBarWidth(bc.GetBarWidth(), spacing)
if totalWithBaseWidth > canvasBox.Width() {
totalLessBarSpacings := canvasBox.Width() - (len(bc.Bars) * spacing)
if totalLessBarSpacings > 0 {
return int(math.Ceil(float64(totalLessBarSpacings) / float64(len(bc.Bars))))
}
return 0
}
return bc.GetBarWidth()
}
func (bc BarChart) calculateTotalBarWidth(barWidth, spacing int) int {
return len(bc.Bars) * (barWidth + spacing)
}
func (bc BarChart) calculateScaledTotalWidth(canvasBox Box) (width, spacing, total int) {
spacing = bc.calculateEffectiveBarSpacing(canvasBox)
width = bc.calculateEffectiveBarWidth(canvasBox, spacing)
total = bc.calculateTotalBarWidth(width, spacing)
return
}
func (bc BarChart) getAdjustedCanvasBox(r Renderer, canvasBox Box, yrange Range, yticks []Tick) Box {
axesOuterBox := canvasBox.Clone()
_, _, totalWidth := bc.calculateScaledTotalWidth(canvasBox)
if bc.XAxis.Show {
xaxisHeight := DefaultVerticalTickHeight
axisStyle := bc.XAxis.InheritFrom(bc.styleDefaultsAxes())
axisStyle.WriteToRenderer(r)
cursor := canvasBox.Left
for _, bar := range bc.Bars {
if len(bar.Label) > 0 {
barLabelBox := Box{
Top: canvasBox.Bottom + DefaultXAxisMargin,
Left: cursor,
Right: cursor + bc.GetBarWidth() + bc.GetBarSpacing(),
Bottom: bc.GetHeight(),
}
lines := Text.WrapFit(r, bar.Label, barLabelBox.Width(), axisStyle)
linesBox := Text.MeasureLines(r, lines, axisStyle)
xaxisHeight = util.Math.MinInt(linesBox.Height()+(2*DefaultXAxisMargin), xaxisHeight)
}
}
xbox := Box{
Top: canvasBox.Top,
Left: canvasBox.Left,
Right: canvasBox.Left + totalWidth,
Bottom: bc.GetHeight() - xaxisHeight,
}
axesOuterBox = axesOuterBox.Grow(xbox)
}
if bc.YAxis.Style.Show {
axesBounds := bc.YAxis.Measure(r, canvasBox, yrange, bc.styleDefaultsAxes(), yticks)
axesOuterBox = axesOuterBox.Grow(axesBounds)
}
return canvasBox.OuterConstrain(bc.box(), axesOuterBox)
}
// box returns the chart bounds as a box.
func (bc BarChart) box() Box {
dpr := bc.Background.Padding.GetRight(10)
dpb := bc.Background.Padding.GetBottom(50)
return Box{
Top: bc.Background.Padding.GetTop(20),
Left: bc.Background.Padding.GetLeft(20),
Right: bc.GetWidth() - dpr,
Bottom: bc.GetHeight() - dpb,
}
}
func (bc BarChart) getBackgroundStyle() Style {
return bc.Background.InheritFrom(bc.styleDefaultsBackground())
}
func (bc BarChart) styleDefaultsBackground() Style {
return Style{
FillColor: bc.GetColorPalette().BackgroundColor(),
StrokeColor: bc.GetColorPalette().BackgroundStrokeColor(),
StrokeWidth: DefaultStrokeWidth,
}
}
func (bc BarChart) styleDefaultsBar(index int) Style {
return Style{
StrokeColor: bc.GetColorPalette().GetSeriesColor(index),
StrokeWidth: 3.0,
FillColor: bc.GetColorPalette().GetSeriesColor(index),
}
}
func (bc BarChart) styleDefaultsTitle() Style {
return bc.TitleStyle.InheritFrom(Style{
FontColor: bc.GetColorPalette().TextColor(),
Font: bc.GetFont(),
FontSize: bc.getTitleFontSize(),
TextHorizontalAlign: TextHorizontalAlignCenter,
TextVerticalAlign: TextVerticalAlignTop,
TextWrap: TextWrapWord,
})
}
func (bc BarChart) getTitleFontSize() float64 {
effectiveDimension := util.Math.MinInt(bc.GetWidth(), bc.GetHeight())
if effectiveDimension >= 2048 {
return 48
} else if effectiveDimension >= 1024 {
return 24
} else if effectiveDimension >= 512 {
return 18
} else if effectiveDimension >= 256 {
return 12
}
return 10
}
func (bc BarChart) styleDefaultsAxes() Style {
return Style{
StrokeColor: bc.GetColorPalette().AxisStrokeColor(),
Font: bc.GetFont(),
FontSize: DefaultAxisFontSize,
FontColor: bc.GetColorPalette().TextColor(),
TextHorizontalAlign: TextHorizontalAlignCenter,
TextVerticalAlign: TextVerticalAlignTop,
TextWrap: TextWrapWord,
}
}
func (bc BarChart) styleDefaultsElements() Style {
return Style{
Font: bc.GetFont(),
}
}
// GetColorPalette returns the color palette for the chart.
func (bc BarChart) GetColorPalette() ColorPalette {
if bc.ColorPalette != nil {
return bc.ColorPalette
}
return AlternateColorPalette
}
package chart
import (
"fmt"
"github.com/wcharczuk/go-chart/seq"
)
// Interface Assertions.
var (
_ Series = (*BollingerBandsSeries)(nil)
)
// BollingerBandsSeries draws bollinger bands for an inner series.
// Bollinger bands are defined by two lines, one at SMA+k*stddev, one at SMA-k*stdev.
type BollingerBandsSeries struct {
Name string
Style Style
YAxis YAxisType
Period int
K float64
InnerSeries ValuesProvider
valueBuffer *seq.Buffer
}
// GetName returns the name of the time series.
func (bbs BollingerBandsSeries) GetName() string {
return bbs.Name
}
// GetStyle returns the line style.
func (bbs BollingerBandsSeries) GetStyle() Style {
return bbs.Style
}
// GetYAxis returns which YAxis the series draws on.
func (bbs BollingerBandsSeries) GetYAxis() YAxisType {
return bbs.YAxis
}
// GetPeriod returns the window size.
func (bbs BollingerBandsSeries) GetPeriod() int {
if bbs.Period == 0 {
return DefaultSimpleMovingAveragePeriod
}
return bbs.Period
}
// GetK returns the K value, or the number of standard deviations above and below
// to band the simple moving average with.
// Typical K value is 2.0.
func (bbs BollingerBandsSeries) GetK(defaults ...float64) float64 {
if bbs.K == 0 {
if len(defaults) > 0 {
return defaults[0]
}
return 2.0
}
return bbs.K
}
// Len returns the number of elements in the series.
func (bbs BollingerBandsSeries) Len() int {
return bbs.InnerSeries.Len()
}
// GetBoundedValues gets the bounded value for the series.
func (bbs *BollingerBandsSeries) GetBoundedValues(index int) (x, y1, y2 float64) {
if bbs.InnerSeries == nil {
return
}
if bbs.valueBuffer == nil || index == 0 {
bbs.valueBuffer = seq.NewBufferWithCapacity(bbs.GetPeriod())
}
if bbs.valueBuffer.Len() >= bbs.GetPeriod() {
bbs.valueBuffer.Dequeue()
}
px, py := bbs.InnerSeries.GetValues(index)
bbs.valueBuffer.Enqueue(py)
x = px
ay := seq.New(bbs.valueBuffer).Average()
std := seq.New(bbs.valueBuffer).StdDev()
y1 = ay + (bbs.GetK() * std)
y2 = ay - (bbs.GetK() * std)
return
}
// GetBoundedLastValues returns the last bounded value for the series.
func (bbs *BollingerBandsSeries) GetBoundedLastValues() (x, y1, y2 float64) {
if bbs.InnerSeries == nil {
return
}
period := bbs.GetPeriod()
seriesLength := bbs.InnerSeries.Len()
startAt := seriesLength - period
if startAt < 0 {
startAt = 0
}
vb := seq.NewBufferWithCapacity(period)
for index := startAt; index < seriesLength; index++ {
xn, yn := bbs.InnerSeries.GetValues(index)
vb.Enqueue(yn)
x = xn
}
ay := seq.Seq{Provider: vb}.Average()
std := seq.Seq{Provider: vb}.StdDev()
y1 = ay + (bbs.GetK() * std)
y2 = ay - (bbs.GetK() * std)
return
}
// Render renders the series.
func (bbs *BollingerBandsSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) {
s := bbs.Style.InheritFrom(defaults.InheritFrom(Style{
StrokeWidth: 1.0,
StrokeColor: DefaultAxisColor.WithAlpha(64),
FillColor: DefaultAxisColor.WithAlpha(32),
}))
Draw.BoundedSeries(r, canvasBox, xrange, yrange, s, bbs, bbs.GetPeriod())
}
// Validate validates the series.
func (bbs BollingerBandsSeries) Validate() error {
if bbs.InnerSeries == nil {
return fmt.Errorf("bollinger bands series requires InnerSeries to be set")
}
return nil
}
package chart
import (
"fmt"
"math"
util "github.com/wcharczuk/go-chart/util"
)
var (
// BoxZero is a preset box that represents an intentional zero value.
BoxZero = Box{IsSet: true}
)
// NewBox returns a new (set) box.
func NewBox(top, left, right, bottom int) Box {
return Box{
IsSet: true,
Top: top,
Left: left,
Right: right,
Bottom: bottom,
}
}
// Box represents the main 4 dimensions of a box.
type Box struct {
Top int
Left int
Right int
Bottom int
IsSet bool
}
// IsZero returns if the box is set or not.
func (b Box) IsZero() bool {
if b.IsSet {
return false
}
return b.Top == 0 && b.Left == 0 && b.Right == 0 && b.Bottom == 0
}
// String returns a string representation of the box.
func (b Box) String() string {
return fmt.Sprintf("box(%d,%d,%d,%d)", b.Top, b.Left, b.Right, b.Bottom)
}
// GetTop returns a coalesced value with a default.
func (b Box) GetTop(defaults ...int) int {
if !b.IsSet && b.Top == 0 {
if len(defaults) > 0 {
return defaults[0]
}
return 0
}
return b.Top
}
// GetLeft returns a coalesced value with a default.
func (b Box) GetLeft(defaults ...int) int {
if !b.IsSet && b.Left == 0 {
if len(defaults) > 0 {
return defaults[0]
}
return 0
}
return b.Left
}
// GetRight returns a coalesced value with a default.
func (b Box) GetRight(defaults ...int) int {
if !b.IsSet && b.Right == 0 {
if len(defaults) > 0 {
return defaults[0]
}
return 0
}
return b.Right
}
// GetBottom returns a coalesced value with a default.
func (b Box) GetBottom(defaults ...int) int {
if !b.IsSet && b.Bottom == 0 {
if len(defaults) > 0 {
return defaults[0]
}
return 0
}
return b.Bottom
}
// Width returns the width
func (b Box) Width() int {
return util.Math.AbsInt(b.Right - b.Left)
}
// Height returns the height
func (b Box) Height() int {
return util.Math.AbsInt(b.Bottom - b.Top)
}
// Center returns the center of the box
func (b Box) Center() (x, y int) {
w2, h2 := b.Width()>>1, b.Height()>>1
return b.Left + w2, b.Top + h2
}
// Aspect returns the aspect ratio of the box.
func (b Box) Aspect() float64 {
return float64(b.Width()) / float64(b.Height())
}
// Clone returns a new copy of the box.
func (b Box) Clone() Box {
return Box{
IsSet: b.IsSet,
Top: b.Top,
Left: b.Left,
Right: b.Right,
Bottom: b.Bottom,
}
}
// IsBiggerThan returns if a box is bigger than another box.
func (b Box) IsBiggerThan(other Box) bool {
return b.Top < other.Top ||
b.Bottom > other.Bottom ||
b.Left < other.Left ||
b.Right > other.Right
}
// IsSmallerThan returns if a box is smaller than another box.
func (b Box) IsSmallerThan(other Box) bool {
return b.Top > other.Top &&
b.Bottom < other.Bottom &&
b.Left > other.Left &&
b.Right < other.Right
}
// Equals returns if the box equals another box.
func (b Box) Equals(other Box) bool {
return b.Top == other.Top &&
b.Left == other.Left &&
b.Right == other.Right &&
b.Bottom == other.Bottom
}
// Grow grows a box based on another box.
func (b Box) Grow(other Box) Box {
return Box{
Top: util.Math.MinInt(b.Top, other.Top),
Left: util.Math.MinInt(b.Left, other.Left),
Right: util.Math.MaxInt(b.Right, other.Right),
Bottom: util.Math.MaxInt(b.Bottom, other.Bottom),
}
}
// Shift pushes a box by x,y.
func (b Box) Shift(x, y int) Box {
return Box{
Top: b.Top + y,
Left: b.Left + x,
Right: b.Right + x,
Bottom: b.Bottom + y,
}
}
// Corners returns the box as a set of corners.
func (b Box) Corners() BoxCorners {
return BoxCorners{
TopLeft: Point{b.Left, b.Top},
TopRight: Point{b.Right, b.Top},
BottomRight: Point{b.Right, b.Bottom},
BottomLeft: Point{b.Left, b.Bottom},
}
}
// Fit is functionally the inverse of grow.
// Fit maintains the original aspect ratio of the `other` box,
// but constrains it to the bounds of the target box.
func (b Box) Fit(other Box) Box {
ba := b.Aspect()
oa := other.Aspect()
if oa == ba {
return b.Clone()
}
bw, bh := float64(b.Width()), float64(b.Height())
bw2 := int(bw) >> 1
bh2 := int(bh) >> 1
if oa > ba { // ex. 16:9 vs. 4:3
var noh2 int
if oa > 1.0 {
noh2 = int(bw/oa) >> 1
} else {
noh2 = int(bh*oa) >> 1
}
return Box{
Top: (b.Top + bh2) - noh2,
Left: b.Left,
Right: b.Right,
Bottom: (b.Top + bh2) + noh2,
}
}
var now2 int
if oa > 1.0 {
now2 = int(bh/oa) >> 1
} else {
now2 = int(bw*oa) >> 1
}
return Box{
Top: b.Top,
Left: (b.Left + bw2) - now2,
Right: (b.Left + bw2) + now2,
Bottom: b.Bottom,
}
}
// Constrain is similar to `Fit` except that it will work
// more literally like the opposite of grow.
func (b Box) Constrain(other Box) Box {
newBox := b.Clone()
newBox.Top = util.Math.MaxInt(newBox.Top, other.Top)
newBox.Left = util.Math.MaxInt(newBox.Left, other.Left)
newBox.Right = util.Math.MinInt(newBox.Right, other.Right)
newBox.Bottom = util.Math.MinInt(newBox.Bottom, other.Bottom)
return newBox
}
// OuterConstrain is similar to `Constraint` with the difference
// that it applies corrections
func (b Box) OuterConstrain(bounds, other Box) Box {
newBox := b.Clone()
if other.Top < bounds.Top {
delta := bounds.Top - other.Top
newBox.Top = b.Top + delta
}
if other.Left < bounds.Left {
delta := bounds.Left - other.Left
newBox.Left = b.Left + delta
}
if other.Right > bounds.Right {
delta := other.Right - bounds.Right
newBox.Right = b.Right - delta
}
if other.Bottom > bounds.Bottom {
delta := other.Bottom - bounds.Bottom
newBox.Bottom = b.Bottom - delta
}
return newBox
}
// BoxCorners is a box with independent corners.
type BoxCorners struct {
TopLeft, TopRight, BottomRight, BottomLeft Point
}
// Box return the BoxCorners as a regular box.
func (bc BoxCorners) Box() Box {
return Box{
Top: util.Math.MinInt(bc.TopLeft.Y, bc.TopRight.Y),
Left: util.Math.MinInt(bc.TopLeft.X, bc.BottomLeft.X),
Right: util.Math.MaxInt(bc.TopRight.X, bc.BottomRight.X),
Bottom: util.Math.MaxInt(bc.BottomLeft.Y, bc.BottomRight.Y),
}
}
// Width returns the width
func (bc BoxCorners) Width() int {
minLeft := util.Math.MinInt(bc.TopLeft.X, bc.BottomLeft.X)
maxRight := util.Math.MaxInt(bc.TopRight.X, bc.BottomRight.X)
return maxRight - minLeft
}
// Height returns the height
func (bc BoxCorners) Height() int {
minTop := util.Math.MinInt(bc.TopLeft.Y, bc.TopRight.Y)
maxBottom := util.Math.MaxInt(bc.BottomLeft.Y, bc.BottomRight.Y)
return maxBottom - minTop
}
// Center returns the center of the box
func (bc BoxCorners) Center() (x, y int) {
left := util.Math.MeanInt(bc.TopLeft.X, bc.BottomLeft.X)
right := util.Math.MeanInt(bc.TopRight.X, bc.BottomRight.X)
x = ((right - left) >> 1) + left
top := util.Math.MeanInt(bc.TopLeft.Y, bc.TopRight.Y)
bottom := util.Math.MeanInt(bc.BottomLeft.Y, bc.BottomRight.Y)
y = ((bottom - top) >> 1) + top
return
}
// Rotate rotates the box.
func (bc BoxCorners) Rotate(thetaDegrees float64) BoxCorners {
cx, cy := bc.Center()
thetaRadians := util.Math.DegreesToRadians(thetaDegrees)
tlx, tly := util.Math.RotateCoordinate(cx, cy, bc.TopLeft.X, bc.TopLeft.Y, thetaRadians)
trx, try := util.Math.RotateCoordinate(cx, cy, bc.TopRight.X, bc.TopRight.Y, thetaRadians)
brx, bry := util.Math.RotateCoordinate(cx, cy, bc.BottomRight.X, bc.BottomRight.Y, thetaRadians)
blx, bly := util.Math.RotateCoordinate(cx, cy, bc.BottomLeft.X, bc.BottomLeft.Y, thetaRadians)
return BoxCorners{
TopLeft: Point{tlx, tly},
TopRight: Point{trx, try},
BottomRight: Point{brx, bry},
BottomLeft: Point{blx, bly},
}
}
// Equals returns if the box equals another box.
func (bc BoxCorners) Equals(other BoxCorners) bool {
return bc.TopLeft.Equals(other.TopLeft) &&
bc.TopRight.Equals(other.TopRight) &&
bc.BottomRight.Equals(other.BottomRight) &&
bc.BottomLeft.Equals(other.BottomLeft)
}
func (bc BoxCorners) String() string {
return fmt.Sprintf("BoxC{%s,%s,%s,%s}", bc.TopLeft.String(), bc.TopRight.String(), bc.BottomRight.String(), bc.BottomLeft.String())
}
// Point is an X,Y pair
type Point struct {
X, Y int
}
// DistanceTo calculates the distance to another point.
func (p Point) DistanceTo(other Point) float64 {
dx := math.Pow(float64(p.X-other.X), 2)
dy := math.Pow(float64(p.Y-other.Y), 2)
return math.Pow(dx+dy, 0.5)
}
// Equals returns if a point equals another point.
func (p Point) Equals(other Point) bool {
return p.X == other.X && p.Y == other.Y
}
// String returns a string representation of the point.
func (p Point) String() string {
return fmt.Sprintf("P{%d,%d}", p.X, p.Y)
}
package chart
import (
"errors"
"fmt"
"io"
"math"
"github.com/golang/freetype/truetype"
util "github.com/wcharczuk/go-chart/util"
)
// Chart is what we're drawing.
type Chart struct {
Title string
TitleStyle Style
ColorPalette ColorPalette
Width int
Height int
DPI float64
Background Style
Canvas Style
XAxis XAxis
YAxis YAxis
YAxisSecondary YAxis
Font *truetype.Font
defaultFont *truetype.Font
Series []Series
Elements []Renderable
}
// GetDPI returns the dpi for the chart.
func (c Chart) GetDPI(defaults ...float64) float64 {
if c.DPI == 0 {
if len(defaults) > 0 {
return defaults[0]
}
return DefaultDPI
}
return c.DPI
}
// GetFont returns the text font.
func (c Chart) GetFont() *truetype.Font {
if c.Font == nil {
return c.defaultFont
}
return c.Font
}
// GetWidth returns the chart width or the default value.
func (c Chart) GetWidth() int {
if c.Width == 0 {
return DefaultChartWidth
}
return c.Width
}
// GetHeight returns the chart height or the default value.
func (c Chart) GetHeight() int {
if c.Height == 0 {
return DefaultChartHeight
}
return c.Height
}
// Render renders the chart with the given renderer to the given io.Writer.
func (c Chart) Render(rp RendererProvider, w io.Writer) error {
if len(c.Series) == 0 {
return errors.New("please provide at least one series")
}
if visibleSeriesErr := c.checkHasVisibleSeries(); visibleSeriesErr != nil {
return visibleSeriesErr
}
c.YAxisSecondary.AxisType = YAxisSecondary
r, err := rp(c.GetWidth(), c.GetHeight())
if err != nil {
return err
}
if c.Font == nil {
defaultFont, err := GetDefaultFont()
if err != nil {
return err
}
c.defaultFont = defaultFont
}
r.SetDPI(c.GetDPI(DefaultDPI))
c.drawBackground(r)
var xt, yt, yta []Tick
xr, yr, yra := c.getRanges()
canvasBox := c.getDefaultCanvasBox()
xf, yf, yfa := c.getValueFormatters()
xr, yr, yra = c.setRangeDomains(canvasBox, xr, yr, yra)
err = c.checkRanges(xr, yr, yra)
if err != nil {
r.Save(w)
return err
}
if c.hasAxes() {
xt, yt, yta = c.getAxesTicks(r, xr, yr, yra, xf, yf, yfa)
canvasBox = c.getAxesAdjustedCanvasBox(r, canvasBox, xr, yr, yra, xt, yt, yta)
xr, yr, yra = c.setRangeDomains(canvasBox, xr, yr, yra)
// do a second pass in case things haven't settled yet.
xt, yt, yta = c.getAxesTicks(r, xr, yr, yra, xf, yf, yfa)
canvasBox = c.getAxesAdjustedCanvasBox(r, canvasBox, xr, yr, yra, xt, yt, yta)
xr, yr, yra = c.setRangeDomains(canvasBox, xr, yr, yra)
}
if c.hasAnnotationSeries() {
canvasBox = c.getAnnotationAdjustedCanvasBox(r, canvasBox, xr, yr, yra, xf, yf, yfa)
xr, yr, yra = c.setRangeDomains(canvasBox, xr, yr, yra)
xt, yt, yta = c.getAxesTicks(r, xr, yr, yra, xf, yf, yfa)
}
c.drawCanvas(r, canvasBox)
c.drawAxes(r, canvasBox, xr, yr, yra, xt, yt, yta)
for index, series := range c.Series {
c.drawSeries(r, canvasBox, xr, yr, yra, series, index)
}
c.drawTitle(r)
for _, a := range c.Elements {
a(r, canvasBox, c.styleDefaultsElements())
}
return r.Save(w)
}
func (c Chart) checkHasVisibleSeries() error {
hasVisibleSeries := false
var style Style
for _, s := range c.Series {
style = s.GetStyle()
hasVisibleSeries = hasVisibleSeries || (style.IsZero() || style.Show)
}
if !hasVisibleSeries {
return fmt.Errorf("must have (1) visible series; make sure if you set a style, you set .Show = true")
}
return nil
}
func (c Chart) validateSeries() error {
var err error
for _, s := range c.Series {
err = s.Validate()
if err != nil {
return err
}
}
return nil
}
func (c Chart) getRanges() (xrange, yrange, yrangeAlt Range) {
var minx, maxx float64 = math.MaxFloat64, -math.MaxFloat64
var miny, maxy float64 = math.MaxFloat64, -math.MaxFloat64
var minya, maxya float64 = math.MaxFloat64, -math.MaxFloat64
seriesMappedToSecondaryAxis := false
// note: a possible future optimization is to not scan the series values if
// all axis are represented by either custom ticks or custom ranges.
for _, s := range c.Series {
if s.GetStyle().IsZero() || s.GetStyle().Show {
seriesAxis := s.GetYAxis()
if bvp, isBoundedValuesProvider := s.(BoundedValuesProvider); isBoundedValuesProvider {
seriesLength := bvp.Len()
for index := 0; index < seriesLength; index++ {
vx, vy1, vy2 := bvp.GetBoundedValues(index)
minx = math.Min(minx, vx)
maxx = math.Max(maxx, vx)
if seriesAxis == YAxisPrimary {
miny = math.Min(miny, vy1)
miny = math.Min(miny, vy2)
maxy = math.Max(maxy, vy1)
maxy = math.Max(maxy, vy2)
} else if seriesAxis == YAxisSecondary {
minya = math.Min(minya, vy1)
minya = math.Min(minya, vy2)
maxya = math.Max(maxya, vy1)
maxya = math.Max(maxya, vy2)
seriesMappedToSecondaryAxis = true
}
}
} else if vp, isValuesProvider := s.(ValuesProvider); isValuesProvider {
seriesLength := vp.Len()
for index := 0; index < seriesLength; index++ {
vx, vy := vp.GetValues(index)
minx = math.Min(minx, vx)
maxx = math.Max(maxx, vx)
if seriesAxis == YAxisPrimary {
miny = math.Min(miny, vy)
maxy = math.Max(maxy, vy)
} else if seriesAxis == YAxisSecondary {
minya = math.Min(minya, vy)
maxya = math.Max(maxya, vy)
seriesMappedToSecondaryAxis = true
}
}
}
}
}
if c.XAxis.Range == nil {
xrange = &ContinuousRange{}
} else {
xrange = c.XAxis.Range
}
if c.YAxis.Range == nil {
yrange = &ContinuousRange{}
} else {
yrange = c.YAxis.Range
}
if c.YAxisSecondary.Range == nil {
yrangeAlt = &ContinuousRange{}
} else {
yrangeAlt = c.YAxisSecondary.Range
}
if len(c.XAxis.Ticks) > 0 {
tickMin, tickMax := math.MaxFloat64, -math.MaxFloat64
for _, t := range c.XAxis.Ticks {
tickMin = math.Min(tickMin, t.Value)
tickMax = math.Max(tickMax, t.Value)
}
xrange.SetMin(tickMin)
xrange.SetMax(tickMax)
} else if xrange.IsZero() {
xrange.SetMin(minx)
xrange.SetMax(maxx)
}
if len(c.YAxis.Ticks) > 0 {
tickMin, tickMax := math.MaxFloat64, -math.MaxFloat64
for _, t := range c.YAxis.Ticks {
tickMin = math.Min(tickMin, t.Value)
tickMax = math.Max(tickMax, t.Value)
}
yrange.SetMin(tickMin)
yrange.SetMax(tickMax)
} else if yrange.IsZero() {
yrange.SetMin(miny)
yrange.SetMax(maxy)
// only round if we're showing the axis
if c.YAxis.Style.Show {
delta := yrange.GetDelta()
roundTo := util.Math.GetRoundToForDelta(delta)
rmin, rmax := util.Math.RoundDown(yrange.GetMin(), roundTo), util.Math.RoundUp(yrange.GetMax(), roundTo)
yrange.SetMin(rmin)
yrange.SetMax(rmax)
}
}
if len(c.YAxisSecondary.Ticks) > 0 {
tickMin, tickMax := math.MaxFloat64, -math.MaxFloat64
for _, t := range c.YAxis.Ticks {
tickMin = math.Min(tickMin, t.Value)
tickMax = math.Max(tickMax, t.Value)
}
yrangeAlt.SetMin(tickMin)
yrangeAlt.SetMax(tickMax)
} else if seriesMappedToSecondaryAxis && yrangeAlt.IsZero() {
yrangeAlt.SetMin(minya)
yrangeAlt.SetMax(maxya)
if c.YAxisSecondary.Style.Show {
delta := yrangeAlt.GetDelta()
roundTo := util.Math.GetRoundToForDelta(delta)
rmin, rmax := util.Math.RoundDown(yrangeAlt.GetMin(), roundTo), util.Math.RoundUp(yrangeAlt.GetMax(), roundTo)
yrangeAlt.SetMin(rmin)
yrangeAlt.SetMax(rmax)
}
}
return
}
func (c Chart) checkRanges(xr, yr, yra Range) error {
xDelta := xr.GetDelta()
if math.IsInf(xDelta, 0) {
return errors.New("infinite x-range delta")
}
if math.IsNaN(xDelta) {
return errors.New("nan x-range delta")
}
if xDelta == 0 {
return errors.New("zero x-range delta; there needs to be at least (2) values")
}
yDelta := yr.GetDelta()
if math.IsInf(yDelta, 0) {
return errors.New("infinite y-range delta")
}
if math.IsNaN(yDelta) {
return errors.New("nan y-range delta")
}
if c.hasSecondarySeries() {
yraDelta := yra.GetDelta()
if math.IsInf(yraDelta, 0) {
return errors.New("infinite secondary y-range delta")
}
if math.IsNaN(yraDelta) {
return errors.New("nan secondary y-range delta")
}
}
return nil
}
func (c Chart) getDefaultCanvasBox() Box {
return c.Box()
}
func (c Chart) getValueFormatters() (x, y, ya ValueFormatter) {
for _, s := range c.Series {
if vfp, isVfp := s.(ValueFormatterProvider); isVfp {
sx, sy := vfp.GetValueFormatters()
if s.GetYAxis() == YAxisPrimary {
x = sx
y = sy
} else if s.GetYAxis() == YAxisSecondary {
x = sx
ya = sy
}
}
}
if c.XAxis.ValueFormatter != nil {
x = c.XAxis.GetValueFormatter()
}
if c.YAxis.ValueFormatter != nil {
y = c.YAxis.GetValueFormatter()
}
if c.YAxisSecondary.ValueFormatter != nil {
ya = c.YAxisSecondary.GetValueFormatter()
}
return
}
func (c Chart) hasAxes() bool {
return c.XAxis.Style.Show || c.YAxis.Style.Show || c.YAxisSecondary.Style.Show
}
func (c Chart) getAxesTicks(r Renderer, xr, yr, yar Range, xf, yf, yfa ValueFormatter) (xticks, yticks, yticksAlt []Tick) {
if c.XAxis.Style.Show {
xticks = c.XAxis.GetTicks(r, xr, c.styleDefaultsAxes(), xf)
}
if c.YAxis.Style.Show {
yticks = c.YAxis.GetTicks(r, yr, c.styleDefaultsAxes(), yf)
}
if c.YAxisSecondary.Style.Show {
yticksAlt = c.YAxisSecondary.GetTicks(r, yar, c.styleDefaultsAxes(), yfa)
}
return
}
func (c Chart) getAxesAdjustedCanvasBox(r Renderer, canvasBox Box, xr, yr, yra Range, xticks, yticks, yticksAlt []Tick) Box {
axesOuterBox := canvasBox.Clone()
if c.XAxis.Style.Show {
axesBounds := c.XAxis.Measure(r, canvasBox, xr, c.styleDefaultsAxes(), xticks)
axesOuterBox = axesOuterBox.Grow(axesBounds)
}
if c.YAxis.Style.Show {
axesBounds := c.YAxis.Measure(r, canvasBox, yr, c.styleDefaultsAxes(), yticks)
axesOuterBox = axesOuterBox.Grow(axesBounds)
}
if c.YAxisSecondary.Style.Show {
axesBounds := c.YAxisSecondary.Measure(r, canvasBox, yra, c.styleDefaultsAxes(), yticksAlt)
axesOuterBox = axesOuterBox.Grow(axesBounds)
}
return canvasBox.OuterConstrain(c.Box(), axesOuterBox)
}
func (c Chart) setRangeDomains(canvasBox Box, xr, yr, yra Range) (Range, Range, Range) {
xr.SetDomain(canvasBox.Width())
yr.SetDomain(canvasBox.Height())
yra.SetDomain(canvasBox.Height())
return xr, yr, yra
}
func (c Chart) hasAnnotationSeries() bool {
for _, s := range c.Series {
if as, isAnnotationSeries := s.(AnnotationSeries); isAnnotationSeries {
if as.Style.IsZero() || as.Style.Show {
return true
}
}
}
return false
}
func (c Chart) hasSecondarySeries() bool {
for _, s := range c.Series {
if s.GetYAxis() == YAxisSecondary {
return true
}
}
return false
}
func (c Chart) getAnnotationAdjustedCanvasBox(r Renderer, canvasBox Box, xr, yr, yra Range, xf, yf, yfa ValueFormatter) Box {
annotationSeriesBox := canvasBox.Clone()
for seriesIndex, s := range c.Series {
if as, isAnnotationSeries := s.(AnnotationSeries); isAnnotationSeries {
if as.Style.IsZero() || as.Style.Show {
style := c.styleDefaultsSeries(seriesIndex)
var annotationBounds Box
if as.YAxis == YAxisPrimary {
annotationBounds = as.Measure(r, canvasBox, xr, yr, style)
} else if as.YAxis == YAxisSecondary {
annotationBounds = as.Measure(r, canvasBox, xr, yra, style)
}
annotationSeriesBox = annotationSeriesBox.Grow(annotationBounds)
}
}
}
return canvasBox.OuterConstrain(c.Box(), annotationSeriesBox)
}
func (c Chart) getBackgroundStyle() Style {
return c.Background.InheritFrom(c.styleDefaultsBackground())
}
func (c Chart) drawBackground(r Renderer) {
Draw.Box(r, Box{
Right: c.GetWidth(),
Bottom: c.GetHeight(),
}, c.getBackgroundStyle())
}
func (c Chart) getCanvasStyle() Style {
return c.Canvas.InheritFrom(c.styleDefaultsCanvas())
}
func (c Chart) drawCanvas(r Renderer, canvasBox Box) {
Draw.Box(r, canvasBox, c.getCanvasStyle())
}
func (c Chart) drawAxes(r Renderer, canvasBox Box, xrange, yrange, yrangeAlt Range, xticks, yticks, yticksAlt []Tick) {
if c.XAxis.Style.Show {
c.XAxis.Render(r, canvasBox, xrange, c.styleDefaultsAxes(), xticks)
}
if c.YAxis.Style.Show {
c.YAxis.Render(r, canvasBox, yrange, c.styleDefaultsAxes(), yticks)
}
if c.YAxisSecondary.Style.Show {
c.YAxisSecondary.Render(r, canvasBox, yrangeAlt, c.styleDefaultsAxes(), yticksAlt)
}
}
func (c Chart) drawSeries(r Renderer, canvasBox Box, xrange, yrange, yrangeAlt Range, s Series, seriesIndex int) {
if s.GetStyle().IsZero() || s.GetStyle().Show {
if s.GetYAxis() == YAxisPrimary {
s.Render(r, canvasBox, xrange, yrange, c.styleDefaultsSeries(seriesIndex))
} else if s.GetYAxis() == YAxisSecondary {
s.Render(r, canvasBox, xrange, yrangeAlt, c.styleDefaultsSeries(seriesIndex))
}
}
}
func (c Chart) drawTitle(r Renderer) {
if len(c.Title) > 0 && c.TitleStyle.Show {
r.SetFont(c.TitleStyle.GetFont(c.GetFont()))
r.SetFontColor(c.TitleStyle.GetFontColor(c.GetColorPalette().TextColor()))
titleFontSize := c.TitleStyle.GetFontSize(DefaultTitleFontSize)
r.SetFontSize(titleFontSize)
textBox := r.MeasureText(c.Title)
textWidth := textBox.Width()
textHeight := textBox.Height()
titleX := (c.GetWidth() >> 1) - (textWidth >> 1)
titleY := c.TitleStyle.Padding.GetTop(DefaultTitleTop) + textHeight
r.Text(c.Title, titleX, titleY)
}
}
func (c Chart) styleDefaultsBackground() Style {
return Style{
FillColor: c.GetColorPalette().BackgroundColor(),
StrokeColor: c.GetColorPalette().BackgroundStrokeColor(),
StrokeWidth: DefaultBackgroundStrokeWidth,
}
}
func (c Chart) styleDefaultsCanvas() Style {
return Style{
FillColor: c.GetColorPalette().CanvasColor(),
StrokeColor: c.GetColorPalette().CanvasStrokeColor(),
StrokeWidth: DefaultCanvasStrokeWidth,
}
}
func (c Chart) styleDefaultsSeries(seriesIndex int) Style {
return Style{
DotColor: c.GetColorPalette().GetSeriesColor(seriesIndex),
StrokeColor: c.GetColorPalette().GetSeriesColor(seriesIndex),
StrokeWidth: DefaultSeriesLineWidth,
Font: c.GetFont(),
FontSize: DefaultFontSize,
}
}
func (c Chart) styleDefaultsAxes() Style {
return Style{
Font: c.GetFont(),
FontColor: c.GetColorPalette().TextColor(),
FontSize: DefaultAxisFontSize,
StrokeColor: c.GetColorPalette().AxisStrokeColor(),
StrokeWidth: DefaultAxisLineWidth,
}
}
func (c Chart) styleDefaultsElements() Style {
return Style{
Font: c.GetFont(),
}
}
// GetColorPalette returns the color palette for the chart.
func (c Chart) GetColorPalette() ColorPalette {
if c.ColorPalette != nil {
return c.ColorPalette
}
return DefaultColorPalette
}
// Box returns the chart bounds as a box.
func (c Chart) Box() Box {
dpr := c.Background.Padding.GetRight(DefaultBackgroundPadding.Right)
dpb := c.Background.Padding.GetBottom(DefaultBackgroundPadding.Bottom)
return Box{
Top: c.Background.Padding.GetTop(DefaultBackgroundPadding.Top),
Left: c.Background.Padding.GetLeft(DefaultBackgroundPadding.Left),
Right: c.GetWidth() - dpr,
Bottom: c.GetHeight() - dpb,
}
}
package chart
import "github.com/wcharczuk/go-chart/drawing"
var (
// ColorWhite is white.
ColorWhite = drawing.Color{R: 255, G: 255, B: 255, A: 255}
// ColorBlue is the basic theme blue color.
ColorBlue = drawing.Color{R: 0, G: 116, B: 217, A: 255}
// ColorCyan is the basic theme cyan color.
ColorCyan = drawing.Color{R: 0, G: 217, B: 210, A: 255}
// ColorGreen is the basic theme green color.
ColorGreen = drawing.Color{R: 0, G: 217, B: 101, A: 255}
// ColorRed is the basic theme red color.
ColorRed = drawing.Color{R: 217, G: 0, B: 116, A: 255}
// ColorOrange is the basic theme orange color.
ColorOrange = drawing.Color{R: 217, G: 101, B: 0, A: 255}
// ColorYellow is the basic theme yellow color.
ColorYellow = drawing.Color{R: 217, G: 210, B: 0, A: 255}
// ColorBlack is the basic theme black color.
ColorBlack = drawing.Color{R: 51, G: 51, B: 51, A: 255}
// ColorLightGray is the basic theme light gray color.
ColorLightGray = drawing.Color{R: 239, G: 239, B: 239, A: 255}
// ColorAlternateBlue is a alternate theme color.
ColorAlternateBlue = drawing.Color{R: 106, G: 195, B: 203, A: 255}
// ColorAlternateGreen is a alternate theme color.
ColorAlternateGreen = drawing.Color{R: 42, G: 190, B: 137, A: 255}
// ColorAlternateGray is a alternate theme color.
ColorAlternateGray = drawing.Color{R: 110, G: 128, B: 139, A: 255}
// ColorAlternateYellow is a alternate theme color.
ColorAlternateYellow = drawing.Color{R: 240, G: 174, B: 90, A: 255}
// ColorAlternateLightGray is a alternate theme color.
ColorAlternateLightGray = drawing.Color{R: 187, G: 190, B: 191, A: 255}
// ColorTransparent is a transparent (alpha zero) color.
ColorTransparent = drawing.Color{R: 1, G: 1, B: 1, A: 0}
)
var (
// DefaultBackgroundColor is the default chart background color.
// It is equivalent to css color:white.
DefaultBackgroundColor = ColorWhite
// DefaultBackgroundStrokeColor is the default chart border color.
// It is equivalent to color:white.
DefaultBackgroundStrokeColor = ColorWhite
// DefaultCanvasColor is the default chart canvas color.
// It is equivalent to css color:white.
DefaultCanvasColor = ColorWhite
// DefaultCanvasStrokeColor is the default chart canvas stroke color.
// It is equivalent to css color:white.
DefaultCanvasStrokeColor = ColorWhite
// DefaultTextColor is the default chart text color.
// It is equivalent to #333333.
DefaultTextColor = ColorBlack
// DefaultAxisColor is the default chart axis line color.
// It is equivalent to #333333.
DefaultAxisColor = ColorBlack
// DefaultStrokeColor is the default chart border color.
// It is equivalent to #efefef.
DefaultStrokeColor = ColorLightGray
// DefaultFillColor is the default fill color.
// It is equivalent to #0074d9.
DefaultFillColor = ColorBlue
// DefaultAnnotationFillColor is the default annotation background color.
DefaultAnnotationFillColor = ColorWhite
// DefaultGridLineColor is the default grid line color.
DefaultGridLineColor = ColorLightGray
)
var (
// DefaultColors are a couple default series colors.
DefaultColors = []drawing.Color{
ColorBlue,
ColorGreen,
ColorRed,
ColorCyan,
ColorOrange,
}
// DefaultAlternateColors are a couple alternate colors.
DefaultAlternateColors = []drawing.Color{
ColorAlternateBlue,
ColorAlternateGreen,
ColorAlternateGray,
ColorAlternateYellow,
ColorBlue,
ColorGreen,
ColorRed,
ColorCyan,
ColorOrange,
}
)
// GetDefaultColor returns a color from the default list by index.
// NOTE: the index will wrap around (using a modulo).
func GetDefaultColor(index int) drawing.Color {
finalIndex := index % len(DefaultColors)
return DefaultColors[finalIndex]
}
// GetAlternateColor returns a color from the default list by index.
// NOTE: the index will wrap around (using a modulo).
func GetAlternateColor(index int) drawing.Color {
finalIndex := index % len(DefaultAlternateColors)
return DefaultAlternateColors[finalIndex]
}
// ColorPalette is a set of colors that.
type ColorPalette interface {
BackgroundColor() drawing.Color
BackgroundStrokeColor() drawing.Color
CanvasColor() drawing.Color
CanvasStrokeColor() drawing.Color
AxisStrokeColor() drawing.Color
TextColor() drawing.Color
GetSeriesColor(index int) drawing.Color
}
// DefaultColorPalette represents the default palatte.
var DefaultColorPalette defaultColorPalette
type defaultColorPalette struct{}
func (dp defaultColorPalette) BackgroundColor() drawing.Color {
return DefaultBackgroundColor
}
func (dp defaultColorPalette) BackgroundStrokeColor() drawing.Color {
return DefaultBackgroundStrokeColor
}
func (dp defaultColorPalette) CanvasColor() drawing.Color {
return DefaultCanvasColor
}
func (dp defaultColorPalette) CanvasStrokeColor() drawing.Color {
return DefaultCanvasStrokeColor
}
func (dp defaultColorPalette) AxisStrokeColor() drawing.Color {
return DefaultAxisColor
}
func (dp defaultColorPalette) TextColor() drawing.Color {
return DefaultTextColor
}
func (dp defaultColorPalette) GetSeriesColor(index int) drawing.Color {
return GetDefaultColor(index)
}
// AlternateColorPalette represents the default palatte.
var AlternateColorPalette alternateColorPalette
type alternateColorPalette struct{}
func (ap alternateColorPalette) BackgroundColor() drawing.Color {
return DefaultBackgroundColor
}
func (ap alternateColorPalette) BackgroundStrokeColor() drawing.Color {
return DefaultBackgroundStrokeColor
}
func (ap alternateColorPalette) CanvasColor() drawing.Color {
return DefaultCanvasColor
}
func (ap alternateColorPalette) CanvasStrokeColor() drawing.Color {
return DefaultCanvasStrokeColor
}
func (ap alternateColorPalette) AxisStrokeColor() drawing.Color {
return DefaultAxisColor
}
func (ap alternateColorPalette) TextColor() drawing.Color {
return DefaultTextColor
}
func (ap alternateColorPalette) GetSeriesColor(index int) drawing.Color {
return GetAlternateColor(index)
}
package chart
// ConcatSeries is a special type of series that concatenates its `InnerSeries`.
type ConcatSeries []Series
// Len returns the length of the concatenated set of series.
func (cs ConcatSeries) Len() int {
total := 0
for _, s := range cs {
if typed, isValuesProvider := s.(ValuesProvider); isValuesProvider {
total += typed.Len()
}
}
return total
}
// GetValue returns the value at the (meta) index (i.e 0 => totalLen-1)
func (cs ConcatSeries) GetValue(index int) (x, y float64) {
cursor := 0
for _, s := range cs {
if typed, isValuesProvider := s.(ValuesProvider); isValuesProvider {
len := typed.Len()
if index < cursor+len {
x, y = typed.GetValues(index - cursor) //FENCEPOSTS.
return
}
cursor += typed.Len()
}
}
return
}
// Validate validates the series.
func (cs ConcatSeries) Validate() error {
var err error
for _, s := range cs {
err = s.Validate()
if err != nil {
return err
}
}
return nil
}
package chart
import (
"fmt"
"math"
)
// ContinuousRange represents a boundary for a set of numbers.
type ContinuousRange struct {
Min float64
Max float64
Domain int
Descending bool
}
// IsDescending returns if the range is descending.
func (r ContinuousRange) IsDescending() bool {
return r.Descending
}
// IsZero returns if the ContinuousRange has been set or not.
func (r ContinuousRange) IsZero() bool {
return (r.Min == 0 || math.IsNaN(r.Min)) &&
(r.Max == 0 || math.IsNaN(r.Max)) &&
r.Domain == 0
}
// GetMin gets the min value for the continuous range.
func (r ContinuousRange) GetMin() float64 {
return r.Min
}
// SetMin sets the min value for the continuous range.
func (r *ContinuousRange) SetMin(min float64) {
r.Min = min
}
// GetMax returns the max value for the continuous range.
func (r ContinuousRange) GetMax() float64 {
return r.Max
}
// SetMax sets the max value for the continuous range.
func (r *ContinuousRange) SetMax(max float64) {
r.Max = max
}
// GetDelta returns the difference between the min and max value.
func (r ContinuousRange) GetDelta() float64 {
return r.Max - r.Min
}
// GetDomain returns the range domain.
func (r ContinuousRange) GetDomain() int {
return r.Domain
}
// SetDomain sets the range domain.
func (r *ContinuousRange) SetDomain(domain int) {
r.Domain = domain
}
// String returns a simple string for the ContinuousRange.
func (r ContinuousRange) String() string {
return fmt.Sprintf("ContinuousRange [%.2f,%.2f] => %d", r.Min, r.Max, r.Domain)
}
// Translate maps a given value into the ContinuousRange space.
func (r ContinuousRange) Translate(value float64) int {
normalized := value - r.Min
ratio := normalized / r.GetDelta()
if r.IsDescending() {
return r.Domain - int(math.Ceil(ratio*float64(r.Domain)))
}
return int(math.Ceil(ratio * float64(r.Domain)))
}
package chart
import "fmt"
// Interface Assertions.
var (
_ Series = (*ContinuousSeries)(nil)
_ FirstValuesProvider = (*ContinuousSeries)(nil)
_ LastValuesProvider = (*ContinuousSeries)(nil)
)
// ContinuousSeries represents a line on a chart.
type ContinuousSeries struct {
Name string
Style Style
YAxis YAxisType
XValueFormatter ValueFormatter
YValueFormatter ValueFormatter
XValues []float64
YValues []float64
}
// GetName returns the name of the time series.
func (cs ContinuousSeries) GetName() string {
return cs.Name
}
// GetStyle returns the line style.
func (cs ContinuousSeries) GetStyle() Style {
return cs.Style
}
// Len returns the number of elements in the series.
func (cs ContinuousSeries) Len() int {
return len(cs.XValues)
}
// GetValues gets the x,y values at a given index.
func (cs ContinuousSeries) GetValues(index int) (float64, float64) {
return cs.XValues[index], cs.YValues[index]
}
// GetFirstValues gets the first x,y values.
func (cs ContinuousSeries) GetFirstValues() (float64, float64) {
return cs.XValues[0], cs.YValues[0]
}
// GetLastValues gets the last x,y values.
func (cs ContinuousSeries) GetLastValues() (float64, float64) {
return cs.XValues[len(cs.XValues)-1], cs.YValues[len(cs.YValues)-1]
}
// GetValueFormatters returns value formatter defaults for the series.
func (cs ContinuousSeries) GetValueFormatters() (x, y ValueFormatter) {
if cs.XValueFormatter != nil {
x = cs.XValueFormatter
} else {
x = FloatValueFormatter
}
if cs.YValueFormatter != nil {
y = cs.YValueFormatter
} else {
y = FloatValueFormatter
}
return
}
// GetYAxis returns which YAxis the series draws on.
func (cs ContinuousSeries) GetYAxis() YAxisType {
return cs.YAxis
}
// Render renders the series.
func (cs ContinuousSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) {
style := cs.Style.InheritFrom(defaults)
Draw.LineSeries(r, canvasBox, xrange, yrange, style, cs)
}
// Validate validates the series.
func (cs ContinuousSeries) Validate() error {
if len(cs.XValues) == 0 {
return fmt.Errorf("continuous series must have xvalues set")
}
if len(cs.YValues) == 0 {
return fmt.Errorf("continuous series must have yvalues set")
}
return nil
}
package chart
import (
"math"
util "github.com/wcharczuk/go-chart/util"
)
var (
// Draw contains helpers for drawing common objects.
Draw = &draw{}
)
type draw struct{}
// LineSeries draws a line series with a renderer.
func (d draw) LineSeries(r Renderer, canvasBox Box, xrange, yrange Range, style Style, vs ValuesProvider) {
if vs.Len() == 0 {
return
}
cb := canvasBox.Bottom
cl := canvasBox.Left
v0x, v0y := vs.GetValues(0)
x0 := cl + xrange.Translate(v0x)
y0 := cb - yrange.Translate(v0y)
yv0 := yrange.Translate(0)
var vx, vy float64
var x, y int
if style.ShouldDrawStroke() && style.ShouldDrawFill() {
style.GetFillOptions().WriteDrawingOptionsToRenderer(r)
r.MoveTo(x0, y0)
for i := 1; i < vs.Len(); i++ {
vx, vy = vs.GetValues(i)
x = cl + xrange.Translate(vx)
y = cb - yrange.Translate(vy)
r.LineTo(x, y)
}
r.LineTo(x, util.Math.MinInt(cb, cb-yv0))
r.LineTo(x0, util.Math.MinInt(cb, cb-yv0))
r.LineTo(x0, y0)
r.Fill()
}
if style.ShouldDrawStroke() {
style.GetStrokeOptions().WriteDrawingOptionsToRenderer(r)
r.MoveTo(x0, y0)
for i := 1; i < vs.Len(); i++ {
vx, vy = vs.GetValues(i)
x = cl + xrange.Translate(vx)
y = cb - yrange.Translate(vy)
r.LineTo(x, y)
}
r.Stroke()
}
if style.ShouldDrawDot() {
defaultDotWidth := style.GetDotWidth()
style.GetDotOptions().WriteDrawingOptionsToRenderer(r)
for i := 0; i < vs.Len(); i++ {
vx, vy = vs.GetValues(i)
x = cl + xrange.Translate(vx)
y = cb - yrange.Translate(vy)
dotWidth := defaultDotWidth
if style.DotWidthProvider != nil {
dotWidth = style.DotWidthProvider(xrange, yrange, i, vx, vy)
}
if style.DotColorProvider != nil {
dotColor := style.DotColorProvider(xrange, yrange, i, vx, vy)
r.SetFillColor(dotColor)
r.SetStrokeColor(dotColor)
}
r.Circle(dotWidth, x, y)
r.FillStroke()
}
}
}
// BoundedSeries draws a series that implements BoundedValuesProvider.
func (d draw) BoundedSeries(r Renderer, canvasBox Box, xrange, yrange Range, style Style, bbs BoundedValuesProvider, drawOffsetIndexes ...int) {
drawOffsetIndex := 0
if len(drawOffsetIndexes) > 0 {
drawOffsetIndex = drawOffsetIndexes[0]
}
cb := canvasBox.Bottom
cl := canvasBox.Left
v0x, v0y1, v0y2 := bbs.GetBoundedValues(0)
x0 := cl + xrange.Translate(v0x)
y0 := cb - yrange.Translate(v0y1)
var vx, vy1, vy2 float64
var x, y int
xvalues := make([]float64, bbs.Len())
xvalues[0] = v0x
y2values := make([]float64, bbs.Len())
y2values[0] = v0y2
style.GetFillAndStrokeOptions().WriteToRenderer(r)
r.MoveTo(x0, y0)
for i := 1; i < bbs.Len(); i++ {
vx, vy1, vy2 = bbs.GetBoundedValues(i)
xvalues[i] = vx
y2values[i] = vy2
x = cl + xrange.Translate(vx)
y = cb - yrange.Translate(vy1)
if i > drawOffsetIndex {
r.LineTo(x, y)
} else {
r.MoveTo(x, y)
}
}
y = cb - yrange.Translate(vy2)
r.LineTo(x, y)
for i := bbs.Len() - 1; i >= drawOffsetIndex; i-- {
vx, vy2 = xvalues[i], y2values[i]
x = cl + xrange.Translate(vx)
y = cb - yrange.Translate(vy2)
r.LineTo(x, y)
}
r.Close()
r.FillStroke()
}
// HistogramSeries draws a value provider as boxes from 0.
func (d draw) HistogramSeries(r Renderer, canvasBox Box, xrange, yrange Range, style Style, vs ValuesProvider, barWidths ...int) {
if vs.Len() == 0 {
return
}
//calculate bar width?
seriesLength := vs.Len()
barWidth := int(math.Floor(float64(xrange.GetDomain()) / float64(seriesLength)))
if len(barWidths) > 0 {
barWidth = barWidths[0]
}
cb := canvasBox.Bottom
cl := canvasBox.Left
//foreach datapoint, draw a box.
for index := 0; index < seriesLength; index++ {
vx, vy := vs.GetValues(index)
y0 := yrange.Translate(0)
x := cl + xrange.Translate(vx)
y := yrange.Translate(vy)
d.Box(r, Box{
Top: cb - y0,
Left: x - (barWidth >> 1),
Right: x + (barWidth >> 1),
Bottom: cb - y,
}, style)
}
}
// MeasureAnnotation measures how big an annotation would be.
func (d draw) MeasureAnnotation(r Renderer, canvasBox Box, style Style, lx, ly int, label string) Box {
style.WriteToRenderer(r)
defer r.ResetStyle()
textBox := r.MeasureText(label)
textWidth := textBox.Width()
textHeight := textBox.Height()
halfTextHeight := textHeight >> 1
pt := style.Padding.GetTop(DefaultAnnotationPadding.Top)
pl := style.Padding.GetLeft(DefaultAnnotationPadding.Left)
pr := style.Padding.GetRight(DefaultAnnotationPadding.Right)
pb := style.Padding.GetBottom(DefaultAnnotationPadding.Bottom)
strokeWidth := style.GetStrokeWidth()
top := ly - (pt + halfTextHeight)
right := lx + pl + pr + textWidth + DefaultAnnotationDeltaWidth + int(strokeWidth)
bottom := ly + (pb + halfTextHeight)
return Box{
Top: top,
Left: lx,
Right: right,
Bottom: bottom,
}
}
// Annotation draws an anotation with a renderer.
func (d draw) Annotation(r Renderer, canvasBox Box, style Style, lx, ly int, label string) {
style.GetTextOptions().WriteToRenderer(r)
defer r.ResetStyle()
textBox := r.MeasureText(label)
textWidth := textBox.Width()
halfTextHeight := textBox.Height() >> 1
style.GetFillAndStrokeOptions().WriteToRenderer(r)
pt := style.Padding.GetTop(DefaultAnnotationPadding.Top)
pl := style.Padding.GetLeft(DefaultAnnotationPadding.Left)
pr := style.Padding.GetRight(DefaultAnnotationPadding.Right)
pb := style.Padding.GetBottom(DefaultAnnotationPadding.Bottom)
textX := lx + pl + DefaultAnnotationDeltaWidth
textY := ly + halfTextHeight
ltx := lx + DefaultAnnotationDeltaWidth
lty := ly - (pt + halfTextHeight)
rtx := lx + pl + pr + textWidth + DefaultAnnotationDeltaWidth
rty := ly - (pt + halfTextHeight)
rbx := lx + pl + pr + textWidth + DefaultAnnotationDeltaWidth
rby := ly + (pb + halfTextHeight)
lbx := lx + DefaultAnnotationDeltaWidth
lby := ly + (pb + halfTextHeight)
r.MoveTo(lx, ly)
r.LineTo(ltx, lty)
r.LineTo(rtx, rty)
r.LineTo(rbx, rby)
r.LineTo(lbx, lby)
r.LineTo(lx, ly)
r.Close()
r.FillStroke()
style.GetTextOptions().WriteToRenderer(r)
r.Text(label, textX, textY)
}
// Box draws a box with a given style.
func (d draw) Box(r Renderer, b Box, s Style) {
s.GetFillAndStrokeOptions().WriteToRenderer(r)
defer r.ResetStyle()
r.MoveTo(b.Left, b.Top)
r.LineTo(b.Right, b.Top)
r.LineTo(b.Right, b.Bottom)
r.LineTo(b.Left, b.Bottom)
r.LineTo(b.Left, b.Top)
r.FillStroke()
}
func (d draw) BoxRotated(r Renderer, b Box, thetaDegrees float64, s Style) {
d.BoxCorners(r, b.Corners().Rotate(thetaDegrees), s)
}
func (d draw) BoxCorners(r Renderer, bc BoxCorners, s Style) {
s.GetFillAndStrokeOptions().WriteToRenderer(r)
defer r.ResetStyle()
r.MoveTo(bc.TopLeft.X, bc.TopLeft.Y)
r.LineTo(bc.TopRight.X, bc.TopRight.Y)
r.LineTo(bc.BottomRight.X, bc.BottomRight.Y)
r.LineTo(bc.BottomLeft.X, bc.BottomLeft.Y)
r.Close()
r.FillStroke()
}
// DrawText draws text with a given style.
func (d draw) Text(r Renderer, text string, x, y int, style Style) {
style.GetTextOptions().WriteToRenderer(r)
defer r.ResetStyle()
r.Text(text, x, y)
}
func (d draw) MeasureText(r Renderer, text string, style Style) Box {
style.GetTextOptions().WriteToRenderer(r)
defer r.ResetStyle()
return r.MeasureText(text)
}
// TextWithin draws the text within a given box.
func (d draw) TextWithin(r Renderer, text string, box Box, style Style) {
style.GetTextOptions().WriteToRenderer(r)
defer r.ResetStyle()
lines := Text.WrapFit(r, text, box.Width(), style)
linesBox := Text.MeasureLines(r, lines, style)
y := box.Top
switch style.GetTextVerticalAlign() {
case TextVerticalAlignBottom, TextVerticalAlignBaseline: // i have to build better baseline handling into measure text
y = y - linesBox.Height()
case TextVerticalAlignMiddle, TextVerticalAlignMiddleBaseline:
y = (y - linesBox.Height()) >> 1
}
var tx, ty int
for _, line := range lines {
lineBox := r.MeasureText(line)
switch style.GetTextHorizontalAlign() {
case TextHorizontalAlignCenter:
tx = box.Left + ((box.Width() - lineBox.Width()) >> 1)
case TextHorizontalAlignRight:
tx = box.Right - lineBox.Width()
default:
tx = box.Left
}
if style.TextRotationDegrees == 0 {
ty = y + lineBox.Height()
} else {
ty = y
}
r.Text(line, tx, ty)
y += lineBox.Height() + style.GetTextLineSpacing()
}
}
package drawing
import (
"fmt"
"strconv"
)
var (
// ColorTransparent is a fully transparent color.
ColorTransparent = Color{}
// ColorWhite is white.
ColorWhite = Color{R: 255, G: 255, B: 255, A: 255}
// ColorBlack is black.
ColorBlack = Color{R: 0, G: 0, B: 0, A: 255}
// ColorRed is red.
ColorRed = Color{R: 255, G: 0, B: 0, A: 255}
// ColorGreen is green.
ColorGreen = Color{R: 0, G: 255, B: 0, A: 255}
// ColorBlue is blue.
ColorBlue = Color{R: 0, G: 0, B: 255, A: 255}
)
func parseHex(hex string) uint8 {
v, _ := strconv.ParseInt(hex, 16, 16)
return uint8(v)
}
// ColorFromHex returns a color from a css hex code.
func ColorFromHex(hex string) Color {
var c Color
if len(hex) == 3 {
c.R = parseHex(string(hex[0])) * 0x11
c.G = parseHex(string(hex[1])) * 0x11
c.B = parseHex(string(hex[2])) * 0x11
} else {
c.R = parseHex(string(hex[0:2]))
c.G = parseHex(string(hex[2:4]))
c.B = parseHex(string(hex[4:6]))
}
c.A = 255
return c
}
// ColorFromAlphaMixedRGBA returns the system alpha mixed rgba values.
func ColorFromAlphaMixedRGBA(r, g, b, a uint32) Color {
fa := float64(a) / 255.0
var c Color
c.R = uint8(float64(r) / fa)
c.G = uint8(float64(g) / fa)
c.B = uint8(float64(b) / fa)
c.A = uint8(a | (a >> 8))
return c
}
// ColorChannelFromFloat returns a normalized byte from a given float value.
func ColorChannelFromFloat(v float64) uint8 {
return uint8(v * 255)
}
// Color is our internal color type because color.Color is bullshit.
type Color struct {
R, G, B, A uint8
}
// RGBA returns the color as a pre-alpha mixed color set.
func (c Color) RGBA() (r, g, b, a uint32) {
fa := float64(c.A) / 255.0
r = uint32(float64(uint32(c.R)) * fa)
r |= r << 8
g = uint32(float64(uint32(c.G)) * fa)
g |= g << 8
b = uint32(float64(uint32(c.B)) * fa)
b |= b << 8
a = uint32(c.A)
a |= a << 8
return
}
// IsZero returns if the color has been set or not.
func (c Color) IsZero() bool {
return c.R == 0 && c.G == 0 && c.B == 0 && c.A == 0
}
// IsTransparent returns if the colors alpha channel is zero.
func (c Color) IsTransparent() bool {
return c.A == 0
}
// WithAlpha returns a copy of the color with a given alpha.
func (c Color) WithAlpha(a uint8) Color {
return Color{
R: c.R,
G: c.G,
B: c.B,
A: a,
}
}
// Equals returns true if the color equals another.
func (c Color) Equals(other Color) bool {
return c.R == other.R &&
c.G == other.G &&
c.B == other.B &&
c.A == other.A
}
// AverageWith averages two colors.
func (c Color) AverageWith(other Color) Color {
return Color{
R: (c.R + other.R) >> 1,
G: (c.G + other.G) >> 1,
B: (c.B + other.B) >> 1,
A: c.A,
}
}
// String returns a css string representation of the color.
func (c Color) String() string {
fa := float64(c.A) / float64(255)
return fmt.Sprintf("rgba(%v,%v,%v,%.1f)", c.R, c.G, c.B, fa)
}
package drawing
import "math"
const (
// CurveRecursionLimit represents the maximum recursion that is really necessary to subsivide a curve into straight lines
CurveRecursionLimit = 32
)
// Cubic
// x1, y1, cpx1, cpy1, cpx2, cpy2, x2, y2 float64
// SubdivideCubic a Bezier cubic curve in 2 equivalents Bezier cubic curves.
// c1 and c2 parameters are the resulting curves
func SubdivideCubic(c, c1, c2 []float64) {
// First point of c is the first point of c1
c1[0], c1[1] = c[0], c[1]
// Last point of c is the last point of c2
c2[6], c2[7] = c[6], c[7]
// Subdivide segment using midpoints
c1[2] = (c[0] + c[2]) / 2
c1[3] = (c[1] + c[3]) / 2
midX := (c[2] + c[4]) / 2
midY := (c[3] + c[5]) / 2
c2[4] = (c[4] + c[6]) / 2
c2[5] = (c[5] + c[7]) / 2
c1[4] = (c1[2] + midX) / 2
c1[5] = (c1[3] + midY) / 2
c2[2] = (midX + c2[4]) / 2
c2[3] = (midY + c2[5]) / 2
c1[6] = (c1[4] + c2[2]) / 2
c1[7] = (c1[5] + c2[3]) / 2
// Last Point of c1 is equal to the first point of c2
c2[0], c2[1] = c1[6], c1[7]
}
// TraceCubic generate lines subdividing the cubic curve using a Liner
// flattening_threshold helps determines the flattening expectation of the curve
func TraceCubic(t Liner, cubic []float64, flatteningThreshold float64) {
// Allocation curves
var curves [CurveRecursionLimit * 8]float64
copy(curves[0:8], cubic[0:8])
i := 0
// current curve
var c []float64
var dx, dy, d2, d3 float64
for i >= 0 {
c = curves[i*8:]
dx = c[6] - c[0]
dy = c[7] - c[1]
d2 = math.Abs((c[2]-c[6])*dy - (c[3]-c[7])*dx)
d3 = math.Abs((c[4]-c[6])*dy - (c[5]-c[7])*dx)
// if it's flat then trace a line
if (d2+d3)*(d2+d3) < flatteningThreshold*(dx*dx+dy*dy) || i == len(curves)-1 {
t.LineTo(c[6], c[7])
i--
} else {
// second half of bezier go lower onto the stack
SubdivideCubic(c, curves[(i+1)*8:], curves[i*8:])
i++
}
}
}
// Quad
// x1, y1, cpx1, cpy2, x2, y2 float64
// SubdivideQuad a Bezier quad curve in 2 equivalents Bezier quad curves.
// c1 and c2 parameters are the resulting curves
func SubdivideQuad(c, c1, c2 []float64) {
// First point of c is the first point of c1
c1[0], c1[1] = c[0], c[1]
// Last point of c is the last point of c2
c2[4], c2[5] = c[4], c[5]
// Subdivide segment using midpoints
c1[2] = (c[0] + c[2]) / 2
c1[3] = (c[1] + c[3]) / 2
c2[2] = (c[2] + c[4]) / 2
c2[3] = (c[3] + c[5]) / 2
c1[4] = (c1[2] + c2[2]) / 2
c1[5] = (c1[3] + c2[3]) / 2
c2[0], c2[1] = c1[4], c1[5]
return
}
func traceWindowIndices(i int) (startAt, endAt int) {
startAt = i * 6
endAt = startAt + 6
return
}
func traceCalcDeltas(c []float64) (dx, dy, d float64) {
dx = c[4] - c[0]
dy = c[5] - c[1]
d = math.Abs(((c[2]-c[4])*dy - (c[3]-c[5])*dx))
return
}
func traceIsFlat(dx, dy, d, threshold float64) bool {
return (d * d) < threshold*(dx*dx+dy*dy)
}
func traceGetWindow(curves []float64, i int) []float64 {
startAt, endAt := traceWindowIndices(i)
return curves[startAt:endAt]
}
// TraceQuad generate lines subdividing the curve using a Liner
// flattening_threshold helps determines the flattening expectation of the curve
func TraceQuad(t Liner, quad []float64, flatteningThreshold float64) {
const curveLen = CurveRecursionLimit * 6
const curveEndIndex = curveLen - 1
const lastIteration = CurveRecursionLimit - 1
// Allocates curves stack
curves := make([]float64, curveLen)
// copy 6 elements from the quad path to the stack
copy(curves[0:6], quad[0:6])
var i int
var c []float64
var dx, dy, d float64
for i >= 0 {
c = traceGetWindow(curves, i)
dx, dy, d = traceCalcDeltas(c)
// bail early if the distance is 0
if d == 0 {
return
}
// if it's flat then trace a line
if traceIsFlat(dx, dy, d, flatteningThreshold) || i == lastIteration {
t.LineTo(c[4], c[5])
i--
} else {
SubdivideQuad(c, traceGetWindow(curves, i+1), traceGetWindow(curves, i))
i++
}
}
}
// TraceArc trace an arc using a Liner
func TraceArc(t Liner, x, y, rx, ry, start, angle, scale float64) (lastX, lastY float64) {
end := start + angle
clockWise := true
if angle < 0 {
clockWise = false
}
ra := (math.Abs(rx) + math.Abs(ry)) / 2
da := math.Acos(ra/(ra+0.125/scale)) * 2
//normalize
if !clockWise {
da = -da
}
angle = start + da
var curX, curY float64
for {
if (angle < end-da/4) != clockWise {
curX = x + math.Cos(end)*rx
curY = y + math.Sin(end)*ry
return curX, curY
}
curX = x + math.Cos(angle)*rx
curY = y + math.Sin(angle)*ry
angle += da
t.LineTo(curX, curY)
}
}
package drawing
// NewDashVertexConverter creates a new dash converter.
func NewDashVertexConverter(dash []float64, dashOffset float64, flattener Flattener) *DashVertexConverter {
var dasher DashVertexConverter
dasher.dash = dash
dasher.currentDash = 0
dasher.dashOffset = dashOffset
dasher.next = flattener
return &dasher
}
// DashVertexConverter is a converter for dash vertexes.
type DashVertexConverter struct {
next Flattener
x, y, distance float64
dash []float64
currentDash int
dashOffset float64
}
// LineTo implements the pathbuilder interface.
func (dasher *DashVertexConverter) LineTo(x, y float64) {
dasher.lineTo(x, y)
}
// MoveTo implements the pathbuilder interface.
func (dasher *DashVertexConverter) MoveTo(x, y float64) {
dasher.next.MoveTo(x, y)
dasher.x, dasher.y = x, y
dasher.distance = dasher.dashOffset
dasher.currentDash = 0
}
// LineJoin implements the pathbuilder interface.
func (dasher *DashVertexConverter) LineJoin() {
dasher.next.LineJoin()
}
// Close implements the pathbuilder interface.
func (dasher *DashVertexConverter) Close() {
dasher.next.Close()
}
// End implements the pathbuilder interface.
func (dasher *DashVertexConverter) End() {
dasher.next.End()
}
func (dasher *DashVertexConverter) lineTo(x, y float64) {
rest := dasher.dash[dasher.currentDash] - dasher.distance
for rest < 0 {
dasher.distance = dasher.distance - dasher.dash[dasher.currentDash]
dasher.currentDash = (dasher.currentDash + 1) % len(dasher.dash)
rest = dasher.dash[dasher.currentDash] - dasher.distance
}
d := distance(dasher.x, dasher.y, x, y)
for d >= rest {
k := rest / d
lx := dasher.x + k*(x-dasher.x)
ly := dasher.y + k*(y-dasher.y)
if dasher.currentDash%2 == 0 {
// line
dasher.next.LineTo(lx, ly)
} else {
// gap
dasher.next.End()
dasher.next.MoveTo(lx, ly)
}
d = d - rest
dasher.x, dasher.y = lx, ly
dasher.currentDash = (dasher.currentDash + 1) % len(dasher.dash)
rest = dasher.dash[dasher.currentDash]
}
dasher.distance = d
if dasher.currentDash%2 == 0 {
// line
dasher.next.LineTo(x, y)
} else {
// gap
dasher.next.End()
dasher.next.MoveTo(x, y)
}
if dasher.distance >= dasher.dash[dasher.currentDash] {
dasher.distance = dasher.distance - dasher.dash[dasher.currentDash]
dasher.currentDash = (dasher.currentDash + 1) % len(dasher.dash)
}
dasher.x, dasher.y = x, y
}
package drawing
// DemuxFlattener is a flattener
type DemuxFlattener struct {
Flatteners []Flattener
}
// MoveTo implements the path builder interface.
func (dc DemuxFlattener) MoveTo(x, y float64) {
for _, flattener := range dc.Flatteners {
flattener.MoveTo(x, y)
}
}
// LineTo implements the path builder interface.
func (dc DemuxFlattener) LineTo(x, y float64) {
for _, flattener := range dc.Flatteners {
flattener.LineTo(x, y)
}
}
// LineJoin implements the path builder interface.
func (dc DemuxFlattener) LineJoin() {
for _, flattener := range dc.Flatteners {
flattener.LineJoin()
}
}
// Close implements the path builder interface.
func (dc DemuxFlattener) Close() {
for _, flattener := range dc.Flatteners {
flattener.Close()
}
}
// End implements the path builder interface.
func (dc DemuxFlattener) End() {
for _, flattener := range dc.Flatteners {
flattener.End()
}
}
package drawing
// Liner receive segment definition
type Liner interface {
// LineTo Draw a line from the current position to the point (x, y)
LineTo(x, y float64)
}
// Flattener receive segment definition
type Flattener interface {
// MoveTo Start a New line from the point (x, y)
MoveTo(x, y float64)
// LineTo Draw a line from the current position to the point (x, y)
LineTo(x, y float64)
// LineJoin add the most recent starting point to close the path to create a polygon
LineJoin()
// Close add the most recent starting point to close the path to create a polygon
Close()
// End mark the current line as finished so we can draw caps
End()
}
// Flatten convert curves into straight segments keeping join segments info
func Flatten(path *Path, flattener Flattener, scale float64) {
// First Point
var startX, startY float64
// Current Point
var x, y float64
var i int
for _, cmp := range path.Components {
switch cmp {
case MoveToComponent:
x, y = path.Points[i], path.Points[i+1]
startX, startY = x, y
if i != 0 {
flattener.End()
}
flattener.MoveTo(x, y)
i += 2
case LineToComponent:
x, y = path.Points[i], path.Points[i+1]
flattener.LineTo(x, y)
flattener.LineJoin()
i += 2
case QuadCurveToComponent:
// we include the previous point for the start of the curve
TraceQuad(flattener, path.Points[i-2:], 0.5)
x, y = path.Points[i+2], path.Points[i+3]
flattener.LineTo(x, y)
i += 4
case CubicCurveToComponent:
TraceCubic(flattener, path.Points[i-2:], 0.5)
x, y = path.Points[i+4], path.Points[i+5]
flattener.LineTo(x, y)
i += 6
case ArcToComponent:
x, y = TraceArc(flattener, path.Points[i], path.Points[i+1], path.Points[i+2], path.Points[i+3], path.Points[i+4], path.Points[i+5], scale)
flattener.LineTo(x, y)
i += 6
case CloseComponent:
flattener.LineTo(startX, startY)
flattener.Close()
}
}
flattener.End()
}
// SegmentedPath is a path of disparate point sectinos.
type SegmentedPath struct {
Points []float64
}
// MoveTo implements the path interface.
func (p *SegmentedPath) MoveTo(x, y float64) {
p.Points = append(p.Points, x, y)
// TODO need to mark this point as moveto
}
// LineTo implements the path interface.
func (p *SegmentedPath) LineTo(x, y float64) {
p.Points = append(p.Points, x, y)
}
// LineJoin implements the path interface.
func (p *SegmentedPath) LineJoin() {
// TODO need to mark the current point as linejoin
}
// Close implements the path interface.
func (p *SegmentedPath) Close() {
// TODO Close
}
// End implements the path interface.
func (p *SegmentedPath) End() {
// Nothing to do
}
package drawing
import (
"github.com/golang/freetype/raster"
"golang.org/x/image/math/fixed"
)
// FtLineBuilder is a builder for freetype raster glyphs.
type FtLineBuilder struct {
Adder raster.Adder
}
// MoveTo implements the path builder interface.
func (liner FtLineBuilder) MoveTo(x, y float64) {
liner.Adder.Start(fixed.Point26_6{X: fixed.Int26_6(x * 64), Y: fixed.Int26_6(y * 64)})
}
// LineTo implements the path builder interface.
func (liner FtLineBuilder) LineTo(x, y float64) {
liner.Adder.Add1(fixed.Point26_6{X: fixed.Int26_6(x * 64), Y: fixed.Int26_6(y * 64)})
}
// LineJoin implements the path builder interface.
func (liner FtLineBuilder) LineJoin() {}
// Close implements the path builder interface.
func (liner FtLineBuilder) Close() {}
// End implements the path builder interface.
func (liner FtLineBuilder) End() {}
package drawing
import (
"image/color"
"image/draw"
)
// PolylineBresenham draws a polyline to an image
func PolylineBresenham(img draw.Image, c color.Color, s ...float64) {
for i := 2; i < len(s); i += 2 {
Bresenham(img, c, int(s[i-2]+0.5), int(s[i-1]+0.5), int(s[i]+0.5), int(s[i+1]+0.5))
}
}
// Bresenham draws a line between (x0, y0) and (x1, y1)
func Bresenham(img draw.Image, color color.Color, x0, y0, x1, y1 int) {
dx := abs(x1 - x0)
dy := abs(y1 - y0)
var sx, sy int
if x0 < x1 {
sx = 1
} else {
sx = -1
}
if y0 < y1 {
sy = 1
} else {
sy = -1
}
err := dx - dy
var e2 int
for {
img.Set(x0, y0, color)
if x0 == x1 && y0 == y1 {
return
}
e2 = 2 * err
if e2 > -dy {
err = err - dy
x0 = x0 + sx
}
if e2 < dx {
err = err + dx
y0 = y0 + sy
}
}
}
package drawing
import (
"math"
)
// Matrix represents an affine transformation
type Matrix [6]float64
const (
epsilon = 1e-6
)
// Determinant compute the determinant of the matrix
func (tr Matrix) Determinant() float64 {
return tr[0]*tr[3] - tr[1]*tr[2]
}
// Transform applies the transformation matrix to points. It modify the points passed in parameter.
func (tr Matrix) Transform(points []float64) {
for i, j := 0, 1; j < len(points); i, j = i+2, j+2 {
x := points[i]
y := points[j]
points[i] = x*tr[0] + y*tr[2] + tr[4]
points[j] = x*tr[1] + y*tr[3] + tr[5]
}
}
// TransformPoint applies the transformation matrix to point. It returns the point the transformed point.
func (tr Matrix) TransformPoint(x, y float64) (xres, yres float64) {
xres = x*tr[0] + y*tr[2] + tr[4]
yres = x*tr[1] + y*tr[3] + tr[5]
return xres, yres
}
func minMax(x, y float64) (min, max float64) {
if x > y {
return y, x
}
return x, y
}
// TransformRectangle applies the transformation matrix to the rectangle represented by the min and the max point of the rectangle
func (tr Matrix) TransformRectangle(x0, y0, x2, y2 float64) (nx0, ny0, nx2, ny2 float64) {
points := []float64{x0, y0, x2, y0, x2, y2, x0, y2}
tr.Transform(points)
points[0], points[2] = minMax(points[0], points[2])
points[4], points[6] = minMax(points[4], points[6])
points[1], points[3] = minMax(points[1], points[3])
points[5], points[7] = minMax(points[5], points[7])
nx0 = math.Min(points[0], points[4])
ny0 = math.Min(points[1], points[5])
nx2 = math.Max(points[2], points[6])
ny2 = math.Max(points[3], points[7])
return nx0, ny0, nx2, ny2
}
// InverseTransform applies the transformation inverse matrix to the rectangle represented by the min and the max point of the rectangle
func (tr Matrix) InverseTransform(points []float64) {
d := tr.Determinant() // matrix determinant
for i, j := 0, 1; j < len(points); i, j = i+2, j+2 {
x := points[i]
y := points[j]
points[i] = ((x-tr[4])*tr[3] - (y-tr[5])*tr[2]) / d
points[j] = ((y-tr[5])*tr[0] - (x-tr[4])*tr[1]) / d
}
}
// InverseTransformPoint applies the transformation inverse matrix to point. It returns the point the transformed point.
func (tr Matrix) InverseTransformPoint(x, y float64) (xres, yres float64) {
d := tr.Determinant() // matrix determinant
xres = ((x-tr[4])*tr[3] - (y-tr[5])*tr[2]) / d
yres = ((y-tr[5])*tr[0] - (x-tr[4])*tr[1]) / d
return xres, yres
}
// VectorTransform applies the transformation matrix to points without using the translation parameter of the affine matrix.
// It modify the points passed in parameter.
func (tr Matrix) VectorTransform(points []float64) {
for i, j := 0, 1; j < len(points); i, j = i+2, j+2 {
x := points[i]
y := points[j]
points[i] = x*tr[0] + y*tr[2]
points[j] = x*tr[1] + y*tr[3]
}
}
// NewIdentityMatrix creates an identity transformation matrix.
func NewIdentityMatrix() Matrix {
return Matrix{1, 0, 0, 1, 0, 0}
}
// NewTranslationMatrix creates a transformation matrix with a translation tx and ty translation parameter
func NewTranslationMatrix(tx, ty float64) Matrix {
return Matrix{1, 0, 0, 1, tx, ty}
}
// NewScaleMatrix creates a transformation matrix with a sx, sy scale factor
func NewScaleMatrix(sx, sy float64) Matrix {
return Matrix{sx, 0, 0, sy, 0, 0}
}
// NewRotationMatrix creates a rotation transformation matrix. angle is in radian
func NewRotationMatrix(angle float64) Matrix {
c := math.Cos(angle)
s := math.Sin(angle)
return Matrix{c, s, -s, c, 0, 0}
}
// NewMatrixFromRects creates a transformation matrix, combining a scale and a translation, that transform rectangle1 into rectangle2.
func NewMatrixFromRects(rectangle1, rectangle2 [4]float64) Matrix {
xScale := (rectangle2[2] - rectangle2[0]) / (rectangle1[2] - rectangle1[0])
yScale := (rectangle2[3] - rectangle2[1]) / (rectangle1[3] - rectangle1[1])
xOffset := rectangle2[0] - (rectangle1[0] * xScale)
yOffset := rectangle2[1] - (rectangle1[1] * yScale)
return Matrix{xScale, 0, 0, yScale, xOffset, yOffset}
}
// Inverse computes the inverse matrix
func (tr *Matrix) Inverse() {
d := tr.Determinant() // matrix determinant
tr0, tr1, tr2, tr3, tr4, tr5 := tr[0], tr[1], tr[2], tr[3], tr[4], tr[5]
tr[0] = tr3 / d
tr[1] = -tr1 / d
tr[2] = -tr2 / d
tr[3] = tr0 / d
tr[4] = (tr2*tr5 - tr3*tr4) / d
tr[5] = (tr1*tr4 - tr0*tr5) / d
}
// Copy copies the matrix.
func (tr Matrix) Copy() Matrix {
var result Matrix
copy(result[:], tr[:])
return result
}
// Compose multiplies trToConcat x tr
func (tr *Matrix) Compose(trToCompose Matrix) {
tr0, tr1, tr2, tr3, tr4, tr5 := tr[0], tr[1], tr[2], tr[3], tr[4], tr[5]
tr[0] = trToCompose[0]*tr0 + trToCompose[1]*tr2
tr[1] = trToCompose[1]*tr3 + trToCompose[0]*tr1
tr[2] = trToCompose[2]*tr0 + trToCompose[3]*tr2
tr[3] = trToCompose[3]*tr3 + trToCompose[2]*tr1
tr[4] = trToCompose[4]*tr0 + trToCompose[5]*tr2 + tr4
tr[5] = trToCompose[5]*tr3 + trToCompose[4]*tr1 + tr5
}
// Scale adds a scale to the matrix
func (tr *Matrix) Scale(sx, sy float64) {
tr[0] = sx * tr[0]
tr[1] = sx * tr[1]
tr[2] = sy * tr[2]
tr[3] = sy * tr[3]
}
// Translate adds a translation to the matrix
func (tr *Matrix) Translate(tx, ty float64) {
tr[4] = tx*tr[0] + ty*tr[2] + tr[4]
tr[5] = ty*tr[3] + tx*tr[1] + tr[5]
}
// Rotate adds a rotation to the matrix.
func (tr *Matrix) Rotate(radians float64) {
c := math.Cos(radians)
s := math.Sin(radians)
t0 := c*tr[0] + s*tr[2]
t1 := s*tr[3] + c*tr[1]
t2 := c*tr[2] - s*tr[0]
t3 := c*tr[3] - s*tr[1]
tr[0] = t0
tr[1] = t1
tr[2] = t2
tr[3] = t3
}
// GetTranslation gets the matrix traslation.
func (tr Matrix) GetTranslation() (x, y float64) {
return tr[4], tr[5]
}
// GetScaling gets the matrix scaling.
func (tr Matrix) GetScaling() (x, y float64) {
return tr[0], tr[3]
}
// GetScale computes a scale for the matrix
func (tr Matrix) GetScale() float64 {
x := 0.707106781*tr[0] + 0.707106781*tr[1]
y := 0.707106781*tr[2] + 0.707106781*tr[3]
return math.Sqrt(x*x + y*y)
}
// ******************** Testing ********************
// Equals tests if a two transformation are equal. A tolerance is applied when comparing matrix elements.
func (tr Matrix) Equals(tr2 Matrix) bool {
for i := 0; i < 6; i = i + 1 {
if !fequals(tr[i], tr2[i]) {
return false
}
}
return true
}
// IsIdentity tests if a transformation is the identity transformation. A tolerance is applied when comparing matrix elements.
func (tr Matrix) IsIdentity() bool {
return fequals(tr[4], 0) && fequals(tr[5], 0) && tr.IsTranslation()
}
// IsTranslation tests if a transformation is is a pure translation. A tolerance is applied when comparing matrix elements.
func (tr Matrix) IsTranslation() bool {
return fequals(tr[0], 1) && fequals(tr[1], 0) && fequals(tr[2], 0) && fequals(tr[3], 1)
}
// fequals compares two floats. return true if the distance between the two floats is less than epsilon, false otherwise
func fequals(float1, float2 float64) bool {
return math.Abs(float1-float2) <= epsilon
}
package drawing
import (
"image"
"image/color"
"golang.org/x/image/draw"
"golang.org/x/image/math/f64"
"github.com/golang/freetype/raster"
)
// Painter implements the freetype raster.Painter and has a SetColor method like the RGBAPainter
type Painter interface {
raster.Painter
SetColor(color color.Color)
}
// DrawImage draws an image into dest using an affine transformation matrix, an op and a filter
func DrawImage(src image.Image, dest draw.Image, tr Matrix, op draw.Op, filter ImageFilter) {
var transformer draw.Transformer
switch filter {
case LinearFilter:
transformer = draw.NearestNeighbor
case BilinearFilter:
transformer = draw.BiLinear
case BicubicFilter:
transformer = draw.CatmullRom
}
transformer.Transform(dest, f64.Aff3{tr[0], tr[1], tr[4], tr[2], tr[3], tr[5]}, src, src.Bounds(), op, nil)
}
package drawing
import (
"fmt"
"math"
)
// PathBuilder describes the interface for path drawing.
type PathBuilder interface {
// LastPoint returns the current point of the current sub path
LastPoint() (x, y float64)
// MoveTo creates a new subpath that start at the specified point
MoveTo(x, y float64)
// LineTo adds a line to the current subpath
LineTo(x, y float64)
// QuadCurveTo adds a quadratic Bézier curve to the current subpath
QuadCurveTo(cx, cy, x, y float64)
// CubicCurveTo adds a cubic Bézier curve to the current subpath
CubicCurveTo(cx1, cy1, cx2, cy2, x, y float64)
// ArcTo adds an arc to the current subpath
ArcTo(cx, cy, rx, ry, startAngle, angle float64)
// Close creates a line from the current point to the last MoveTo
// point (if not the same) and mark the path as closed so the
// first and last lines join nicely.
Close()
}
// PathComponent represents component of a path
type PathComponent int
const (
// MoveToComponent is a MoveTo component in a Path
MoveToComponent PathComponent = iota
// LineToComponent is a LineTo component in a Path
LineToComponent
// QuadCurveToComponent is a QuadCurveTo component in a Path
QuadCurveToComponent
// CubicCurveToComponent is a CubicCurveTo component in a Path
CubicCurveToComponent
// ArcToComponent is a ArcTo component in a Path
ArcToComponent
// CloseComponent is a ArcTo component in a Path
CloseComponent
)
// Path stores points
type Path struct {
// Components is a slice of PathComponent in a Path and mark the role of each points in the Path
Components []PathComponent
// Points are combined with Components to have a specific role in the path
Points []float64
// Last Point of the Path
x, y float64
}
func (p *Path) appendToPath(cmd PathComponent, points ...float64) {
p.Components = append(p.Components, cmd)
p.Points = append(p.Points, points...)
}
// LastPoint returns the current point of the current path
func (p *Path) LastPoint() (x, y float64) {
return p.x, p.y
}
// MoveTo starts a new path at (x, y) position
func (p *Path) MoveTo(x, y float64) {
p.appendToPath(MoveToComponent, x, y)
p.x = x
p.y = y
}
// LineTo adds a line to the current path
func (p *Path) LineTo(x, y float64) {
if len(p.Components) == 0 { //special case when no move has been done
p.MoveTo(0, 0)
}
p.appendToPath(LineToComponent, x, y)
p.x = x
p.y = y
}
// QuadCurveTo adds a quadratic bezier curve to the current path
func (p *Path) QuadCurveTo(cx, cy, x, y float64) {
if len(p.Components) == 0 { //special case when no move has been done
p.MoveTo(0, 0)
}
p.appendToPath(QuadCurveToComponent, cx, cy, x, y)
p.x = x
p.y = y
}
// CubicCurveTo adds a cubic bezier curve to the current path
func (p *Path) CubicCurveTo(cx1, cy1, cx2, cy2, x, y float64) {
if len(p.Components) == 0 { //special case when no move has been done
p.MoveTo(0, 0)
}
p.appendToPath(CubicCurveToComponent, cx1, cy1, cx2, cy2, x, y)
p.x = x
p.y = y
}
// ArcTo adds an arc to the path
func (p *Path) ArcTo(cx, cy, rx, ry, startAngle, delta float64) {
endAngle := startAngle + delta
clockWise := true
if delta < 0 {
clockWise = false
}
// normalize
if clockWise {
for endAngle < startAngle {
endAngle += math.Pi * 2.0
}
} else {
for startAngle < endAngle {
startAngle += math.Pi * 2.0
}
}
startX := cx + math.Cos(startAngle)*rx
startY := cy + math.Sin(startAngle)*ry
if len(p.Components) > 0 {
p.LineTo(startX, startY)
} else {
p.MoveTo(startX, startY)
}
p.appendToPath(ArcToComponent, cx, cy, rx, ry, startAngle, delta)
p.x = cx + math.Cos(endAngle)*rx
p.y = cy + math.Sin(endAngle)*ry
}
// Close closes the current path
func (p *Path) Close() {
p.appendToPath(CloseComponent)
}
// Copy make a clone of the current path and return it
func (p *Path) Copy() (dest *Path) {
dest = new(Path)
dest.Components = make([]PathComponent, len(p.Components))
copy(dest.Components, p.Components)
dest.Points = make([]float64, len(p.Points))
copy(dest.Points, p.Points)
dest.x, dest.y = p.x, p.y
return dest
}
// Clear reset the path
func (p *Path) Clear() {
p.Components = p.Components[0:0]
p.Points = p.Points[0:0]
return
}
// IsEmpty returns true if the path is empty
func (p *Path) IsEmpty() bool {
return len(p.Components) == 0
}
// String returns a debug text view of the path
func (p *Path) String() string {
s := ""
j := 0
for _, cmd := range p.Components {
switch cmd {
case MoveToComponent:
s += fmt.Sprintf("MoveTo: %f, %f\n", p.Points[j], p.Points[j+1])
j = j + 2
case LineToComponent:
s += fmt.Sprintf("LineTo: %f, %f\n", p.Points[j], p.Points[j+1])
j = j + 2
case QuadCurveToComponent:
s += fmt.Sprintf("QuadCurveTo: %f, %f, %f, %f\n", p.Points[j], p.Points[j+1], p.Points[j+2], p.Points[j+3])
j = j + 4
case CubicCurveToComponent:
s += fmt.Sprintf("CubicCurveTo: %f, %f, %f, %f, %f, %f\n", p.Points[j], p.Points[j+1], p.Points[j+2], p.Points[j+3], p.Points[j+4], p.Points[j+5])
j = j + 6
case ArcToComponent:
s += fmt.Sprintf("ArcTo: %f, %f, %f, %f, %f, %f\n", p.Points[j], p.Points[j+1], p.Points[j+2], p.Points[j+3], p.Points[j+4], p.Points[j+5])
j = j + 6
case CloseComponent:
s += "Close\n"
}
}
return s
}
package drawing
import (
"errors"
"image"
"image/color"
"math"
"github.com/golang/freetype/raster"
"github.com/golang/freetype/truetype"
"golang.org/x/image/draw"
"golang.org/x/image/font"
"golang.org/x/image/math/fixed"
)
// NewRasterGraphicContext creates a new Graphic context from an image.
func NewRasterGraphicContext(img draw.Image) (*RasterGraphicContext, error) {
var painter Painter
switch selectImage := img.(type) {
case *image.RGBA:
painter = raster.NewRGBAPainter(selectImage)
default:
return nil, errors.New("NewRasterGraphicContext() :: invalid image type")
}
return NewRasterGraphicContextWithPainter(img, painter), nil
}
// NewRasterGraphicContextWithPainter creates a new Graphic context from an image and a Painter (see Freetype-go)
func NewRasterGraphicContextWithPainter(img draw.Image, painter Painter) *RasterGraphicContext {
width, height := img.Bounds().Dx(), img.Bounds().Dy()
return &RasterGraphicContext{
NewStackGraphicContext(),
img,
painter,
raster.NewRasterizer(width, height),
raster.NewRasterizer(width, height),
&truetype.GlyphBuf{},
DefaultDPI,
}
}
// RasterGraphicContext is the implementation of GraphicContext for a raster image
type RasterGraphicContext struct {
*StackGraphicContext
img draw.Image
painter Painter
fillRasterizer *raster.Rasterizer
strokeRasterizer *raster.Rasterizer
glyphBuf *truetype.GlyphBuf
DPI float64
}
// SetDPI sets the screen resolution in dots per inch.
func (rgc *RasterGraphicContext) SetDPI(dpi float64) {
rgc.DPI = dpi
rgc.recalc()
}
// GetDPI returns the resolution of the Image GraphicContext
func (rgc *RasterGraphicContext) GetDPI() float64 {
return rgc.DPI
}
// Clear fills the current canvas with a default transparent color
func (rgc *RasterGraphicContext) Clear() {
width, height := rgc.img.Bounds().Dx(), rgc.img.Bounds().Dy()
rgc.ClearRect(0, 0, width, height)
}
// ClearRect fills the current canvas with a default transparent color at the specified rectangle
func (rgc *RasterGraphicContext) ClearRect(x1, y1, x2, y2 int) {
imageColor := image.NewUniform(rgc.current.FillColor)
draw.Draw(rgc.img, image.Rect(x1, y1, x2, y2), imageColor, image.ZP, draw.Over)
}
// DrawImage draws the raster image in the current canvas
func (rgc *RasterGraphicContext) DrawImage(img image.Image) {
DrawImage(img, rgc.img, rgc.current.Tr, draw.Over, BilinearFilter)
}
// FillString draws the text at point (0, 0)
func (rgc *RasterGraphicContext) FillString(text string) (cursor float64, err error) {
cursor, err = rgc.FillStringAt(text, 0, 0)
return
}
// FillStringAt draws the text at the specified point (x, y)
func (rgc *RasterGraphicContext) FillStringAt(text string, x, y float64) (cursor float64, err error) {
cursor, err = rgc.CreateStringPath(text, x, y)
rgc.Fill()
return
}
// StrokeString draws the contour of the text at point (0, 0)
func (rgc *RasterGraphicContext) StrokeString(text string) (cursor float64, err error) {
cursor, err = rgc.StrokeStringAt(text, 0, 0)
return
}
// StrokeStringAt draws the contour of the text at point (x, y)
func (rgc *RasterGraphicContext) StrokeStringAt(text string, x, y float64) (cursor float64, err error) {
cursor, err = rgc.CreateStringPath(text, x, y)
rgc.Stroke()
return
}
func (rgc *RasterGraphicContext) drawGlyph(glyph truetype.Index, dx, dy float64) error {
if err := rgc.glyphBuf.Load(rgc.current.Font, fixed.Int26_6(rgc.current.Scale), glyph, font.HintingNone); err != nil {
return err
}
e0 := 0
for _, e1 := range rgc.glyphBuf.Ends {
DrawContour(rgc, rgc.glyphBuf.Points[e0:e1], dx, dy)
e0 = e1
}
return nil
}
// CreateStringPath creates a path from the string s at x, y, and returns the string width.
// The text is placed so that the left edge of the em square of the first character of s
// and the baseline intersect at x, y. The majority of the affected pixels will be
// above and to the right of the point, but some may be below or to the left.
// For example, drawing a string that starts with a 'J' in an italic font may
// affect pixels below and left of the point.
func (rgc *RasterGraphicContext) CreateStringPath(s string, x, y float64) (cursor float64, err error) {
f := rgc.GetFont()
if f == nil {
err = errors.New("No font loaded, cannot continue")
return
}
rgc.recalc()
startx := x
prev, hasPrev := truetype.Index(0), false
for _, rc := range s {
index := f.Index(rc)
if hasPrev {
x += fUnitsToFloat64(f.Kern(fixed.Int26_6(rgc.current.Scale), prev, index))
}
err = rgc.drawGlyph(index, x, y)
if err != nil {
cursor = x - startx
return
}
x += fUnitsToFloat64(f.HMetric(fixed.Int26_6(rgc.current.Scale), index).AdvanceWidth)
prev, hasPrev = index, true
}
cursor = x - startx
return
}
// GetStringBounds returns the approximate pixel bounds of a string.
func (rgc *RasterGraphicContext) GetStringBounds(s string) (left, top, right, bottom float64, err error) {
f := rgc.GetFont()
if f == nil {
err = errors.New("No font loaded, cannot continue")
return
}
rgc.recalc()
left = math.MaxFloat64
top = math.MaxFloat64
cursor := 0.0
prev, hasPrev := truetype.Index(0), false
for _, rc := range s {
index := f.Index(rc)
if hasPrev {
cursor += fUnitsToFloat64(f.Kern(fixed.Int26_6(rgc.current.Scale), prev, index))
}
if err = rgc.glyphBuf.Load(rgc.current.Font, fixed.Int26_6(rgc.current.Scale), index, font.HintingNone); err != nil {
return
}
e0 := 0
for _, e1 := range rgc.glyphBuf.Ends {
ps := rgc.glyphBuf.Points[e0:e1]
for _, p := range ps {
x, y := pointToF64Point(p)
top = math.Min(top, y)
bottom = math.Max(bottom, y)
left = math.Min(left, x+cursor)
right = math.Max(right, x+cursor)
}
e0 = e1
}
cursor += fUnitsToFloat64(f.HMetric(fixed.Int26_6(rgc.current.Scale), index).AdvanceWidth)
prev, hasPrev = index, true
}
return
}
// recalc recalculates scale and bounds values from the font size, screen
// resolution and font metrics, and invalidates the glyph cache.
func (rgc *RasterGraphicContext) recalc() {
rgc.current.Scale = rgc.current.FontSizePoints * float64(rgc.DPI)
}
// SetFont sets the font used to draw text.
func (rgc *RasterGraphicContext) SetFont(font *truetype.Font) {
rgc.current.Font = font
}
// GetFont returns the font used to draw text.
func (rgc *RasterGraphicContext) GetFont() *truetype.Font {
return rgc.current.Font
}
// SetFontSize sets the font size in points (as in ``a 12 point font'').
func (rgc *RasterGraphicContext) SetFontSize(fontSizePoints float64) {
rgc.current.FontSizePoints = fontSizePoints
rgc.recalc()
}
func (rgc *RasterGraphicContext) paint(rasterizer *raster.Rasterizer, color color.Color) {
rgc.painter.SetColor(color)
rasterizer.Rasterize(rgc.painter)
rasterizer.Clear()
rgc.current.Path.Clear()
}
// Stroke strokes the paths with the color specified by SetStrokeColor
func (rgc *RasterGraphicContext) Stroke(paths ...*Path) {
paths = append(paths, rgc.current.Path)
rgc.strokeRasterizer.UseNonZeroWinding = true
stroker := NewLineStroker(rgc.current.Cap, rgc.current.Join, Transformer{Tr: rgc.current.Tr, Flattener: FtLineBuilder{Adder: rgc.strokeRasterizer}})
stroker.HalfLineWidth = rgc.current.LineWidth / 2
var liner Flattener
if rgc.current.Dash != nil && len(rgc.current.Dash) > 0 {
liner = NewDashVertexConverter(rgc.current.Dash, rgc.current.DashOffset, stroker)
} else {
liner = stroker
}
for _, p := range paths {
Flatten(p, liner, rgc.current.Tr.GetScale())
}
rgc.paint(rgc.strokeRasterizer, rgc.current.StrokeColor)
}
// Fill fills the paths with the color specified by SetFillColor
func (rgc *RasterGraphicContext) Fill(paths ...*Path) {
paths = append(paths, rgc.current.Path)
rgc.fillRasterizer.UseNonZeroWinding = rgc.current.FillRule == FillRuleWinding
flattener := Transformer{Tr: rgc.current.Tr, Flattener: FtLineBuilder{Adder: rgc.fillRasterizer}}
for _, p := range paths {
Flatten(p, flattener, rgc.current.Tr.GetScale())
}
rgc.paint(rgc.fillRasterizer, rgc.current.FillColor)
}
// FillStroke first fills the paths and than strokes them
func (rgc *RasterGraphicContext) FillStroke(paths ...*Path) {
paths = append(paths, rgc.current.Path)
rgc.fillRasterizer.UseNonZeroWinding = rgc.current.FillRule == FillRuleWinding
rgc.strokeRasterizer.UseNonZeroWinding = true
flattener := Transformer{Tr: rgc.current.Tr, Flattener: FtLineBuilder{Adder: rgc.fillRasterizer}}
stroker := NewLineStroker(rgc.current.Cap, rgc.current.Join, Transformer{Tr: rgc.current.Tr, Flattener: FtLineBuilder{Adder: rgc.strokeRasterizer}})
stroker.HalfLineWidth = rgc.current.LineWidth / 2
var liner Flattener
if rgc.current.Dash != nil && len(rgc.current.Dash) > 0 {
liner = NewDashVertexConverter(rgc.current.Dash, rgc.current.DashOffset, stroker)
} else {
liner = stroker
}
demux := DemuxFlattener{Flatteners: []Flattener{flattener, liner}}
for _, p := range paths {
Flatten(p, demux, rgc.current.Tr.GetScale())
}
// Fill
rgc.paint(rgc.fillRasterizer, rgc.current.FillColor)
// Stroke
rgc.paint(rgc.strokeRasterizer, rgc.current.StrokeColor)
}
package drawing
import (
"image"
"image/color"
"github.com/golang/freetype/truetype"
)
// StackGraphicContext is a context that does thngs.
type StackGraphicContext struct {
current *ContextStack
}
// ContextStack is a graphic context implementation.
type ContextStack struct {
Tr Matrix
Path *Path
LineWidth float64
Dash []float64
DashOffset float64
StrokeColor color.Color
FillColor color.Color
FillRule FillRule
Cap LineCap
Join LineJoin
FontSizePoints float64
Font *truetype.Font
Scale float64
Previous *ContextStack
}
// NewStackGraphicContext Create a new Graphic context from an image
func NewStackGraphicContext() *StackGraphicContext {
gc := &StackGraphicContext{}
gc.current = new(ContextStack)
gc.current.Tr = NewIdentityMatrix()
gc.current.Path = new(Path)
gc.current.LineWidth = 1.0
gc.current.StrokeColor = image.Black
gc.current.FillColor = image.White
gc.current.Cap = RoundCap
gc.current.FillRule = FillRuleEvenOdd
gc.current.Join = RoundJoin
gc.current.FontSizePoints = 10
return gc
}
// GetMatrixTransform returns the matrix transform.
func (gc *StackGraphicContext) GetMatrixTransform() Matrix {
return gc.current.Tr
}
// SetMatrixTransform sets the matrix transform.
func (gc *StackGraphicContext) SetMatrixTransform(tr Matrix) {
gc.current.Tr = tr
}
// ComposeMatrixTransform composes a transform into the current transform.
func (gc *StackGraphicContext) ComposeMatrixTransform(tr Matrix) {
gc.current.Tr.Compose(tr)
}
// Rotate rotates the matrix transform by an angle in degrees.
func (gc *StackGraphicContext) Rotate(angle float64) {
gc.current.Tr.Rotate(angle)
}
// Translate translates a transform.
func (gc *StackGraphicContext) Translate(tx, ty float64) {
gc.current.Tr.Translate(tx, ty)
}
// Scale scales a transform.
func (gc *StackGraphicContext) Scale(sx, sy float64) {
gc.current.Tr.Scale(sx, sy)
}
// SetStrokeColor sets the stroke color.
func (gc *StackGraphicContext) SetStrokeColor(c color.Color) {
gc.current.StrokeColor = c
}
// SetFillColor sets the fill color.
func (gc *StackGraphicContext) SetFillColor(c color.Color) {
gc.current.FillColor = c
}
// SetFillRule sets the fill rule.
func (gc *StackGraphicContext) SetFillRule(f FillRule) {
gc.current.FillRule = f
}
// SetLineWidth sets the line width.
func (gc *StackGraphicContext) SetLineWidth(lineWidth float64) {
gc.current.LineWidth = lineWidth
}
// SetLineCap sets the line cap.
func (gc *StackGraphicContext) SetLineCap(cap LineCap) {
gc.current.Cap = cap
}
// SetLineJoin sets the line join.
func (gc *StackGraphicContext) SetLineJoin(join LineJoin) {
gc.current.Join = join
}
// SetLineDash sets the line dash.
func (gc *StackGraphicContext) SetLineDash(dash []float64, dashOffset float64) {
gc.current.Dash = dash
gc.current.DashOffset = dashOffset
}
// SetFontSize sets the font size.
func (gc *StackGraphicContext) SetFontSize(fontSizePoints float64) {
gc.current.FontSizePoints = fontSizePoints
}
// GetFontSize gets the font size.
func (gc *StackGraphicContext) GetFontSize() float64 {
return gc.current.FontSizePoints
}
// SetFont sets the current font.
func (gc *StackGraphicContext) SetFont(f *truetype.Font) {
gc.current.Font = f
}
// GetFont returns the font.
func (gc *StackGraphicContext) GetFont() *truetype.Font {
return gc.current.Font
}
// BeginPath starts a new path.
func (gc *StackGraphicContext) BeginPath() {
gc.current.Path.Clear()
}
// IsEmpty returns if the path is empty.
func (gc *StackGraphicContext) IsEmpty() bool {
return gc.current.Path.IsEmpty()
}
// LastPoint returns the last point on the path.
func (gc *StackGraphicContext) LastPoint() (x float64, y float64) {
return gc.current.Path.LastPoint()
}
// MoveTo moves the cursor for a path.
func (gc *StackGraphicContext) MoveTo(x, y float64) {
gc.current.Path.MoveTo(x, y)
}
// LineTo draws a line.
func (gc *StackGraphicContext) LineTo(x, y float64) {
gc.current.Path.LineTo(x, y)
}
// QuadCurveTo draws a quad curve.
func (gc *StackGraphicContext) QuadCurveTo(cx, cy, x, y float64) {
gc.current.Path.QuadCurveTo(cx, cy, x, y)
}
// CubicCurveTo draws a cubic curve.
func (gc *StackGraphicContext) CubicCurveTo(cx1, cy1, cx2, cy2, x, y float64) {
gc.current.Path.CubicCurveTo(cx1, cy1, cx2, cy2, x, y)
}
// ArcTo draws an arc.
func (gc *StackGraphicContext) ArcTo(cx, cy, rx, ry, startAngle, delta float64) {
gc.current.Path.ArcTo(cx, cy, rx, ry, startAngle, delta)
}
// Close closes a path.
func (gc *StackGraphicContext) Close() {
gc.current.Path.Close()
}
// Save pushes a context onto the stack.
func (gc *StackGraphicContext) Save() {
context := new(ContextStack)
context.FontSizePoints = gc.current.FontSizePoints
context.Font = gc.current.Font
context.LineWidth = gc.current.LineWidth
context.StrokeColor = gc.current.StrokeColor
context.FillColor = gc.current.FillColor
context.FillRule = gc.current.FillRule
context.Dash = gc.current.Dash
context.DashOffset = gc.current.DashOffset
context.Cap = gc.current.Cap
context.Join = gc.current.Join
context.Path = gc.current.Path.Copy()
context.Font = gc.current.Font
context.Scale = gc.current.Scale
copy(context.Tr[:], gc.current.Tr[:])
context.Previous = gc.current
gc.current = context
}
// Restore restores the previous context.
func (gc *StackGraphicContext) Restore() {
if gc.current.Previous != nil {
oldContext := gc.current
gc.current = gc.current.Previous
oldContext.Previous = nil
}
}
// Copyright 2010 The draw2d Authors. All rights reserved.
// created: 13/12/2010 by Laurent Le Goff
package drawing
// NewLineStroker creates a new line stroker.
func NewLineStroker(c LineCap, j LineJoin, flattener Flattener) *LineStroker {
l := new(LineStroker)
l.Flattener = flattener
l.HalfLineWidth = 0.5
l.Cap = c
l.Join = j
return l
}
// LineStroker draws the stroke portion of a line.
type LineStroker struct {
Flattener Flattener
HalfLineWidth float64
Cap LineCap
Join LineJoin
vertices []float64
rewind []float64
x, y, nx, ny float64
}
// MoveTo implements the path builder interface.
func (l *LineStroker) MoveTo(x, y float64) {
l.x, l.y = x, y
}
// LineTo implements the path builder interface.
func (l *LineStroker) LineTo(x, y float64) {
l.line(l.x, l.y, x, y)
}
// LineJoin implements the path builder interface.
func (l *LineStroker) LineJoin() {}
func (l *LineStroker) line(x1, y1, x2, y2 float64) {
dx := (x2 - x1)
dy := (y2 - y1)
d := vectorDistance(dx, dy)
if d != 0 {
nx := dy * l.HalfLineWidth / d
ny := -(dx * l.HalfLineWidth / d)
l.appendVertex(x1+nx, y1+ny, x2+nx, y2+ny, x1-nx, y1-ny, x2-nx, y2-ny)
l.x, l.y, l.nx, l.ny = x2, y2, nx, ny
}
}
// Close implements the path builder interface.
func (l *LineStroker) Close() {
if len(l.vertices) > 1 {
l.appendVertex(l.vertices[0], l.vertices[1], l.rewind[0], l.rewind[1])
}
}
// End implements the path builder interface.
func (l *LineStroker) End() {
if len(l.vertices) > 1 {
l.Flattener.MoveTo(l.vertices[0], l.vertices[1])
for i, j := 2, 3; j < len(l.vertices); i, j = i+2, j+2 {
l.Flattener.LineTo(l.vertices[i], l.vertices[j])
}
}
for i, j := len(l.rewind)-2, len(l.rewind)-1; j > 0; i, j = i-2, j-2 {
l.Flattener.LineTo(l.rewind[i], l.rewind[j])
}
if len(l.vertices) > 1 {
l.Flattener.LineTo(l.vertices[0], l.vertices[1])
}
l.Flattener.End()
// reinit vertices
l.vertices = l.vertices[0:0]
l.rewind = l.rewind[0:0]
l.x, l.y, l.nx, l.ny = 0, 0, 0, 0
}
func (l *LineStroker) appendVertex(vertices ...float64) {
s := len(vertices) / 2
l.vertices = append(l.vertices, vertices[:s]...)
l.rewind = append(l.rewind, vertices[s:]...)
}
package drawing
import (
"github.com/golang/freetype/truetype"
"golang.org/x/image/math/fixed"
)
// DrawContour draws the given closed contour at the given sub-pixel offset.
func DrawContour(path PathBuilder, ps []truetype.Point, dx, dy float64) {
if len(ps) == 0 {
return
}
startX, startY := pointToF64Point(ps[0])
path.MoveTo(startX+dx, startY+dy)
q0X, q0Y, on0 := startX, startY, true
for _, p := range ps[1:] {
qX, qY := pointToF64Point(p)
on := p.Flags&0x01 != 0
if on {
if on0 {
path.LineTo(qX+dx, qY+dy)
} else {
path.QuadCurveTo(q0X+dx, q0Y+dy, qX+dx, qY+dy)
}
} else if !on0 {
midX := (q0X + qX) / 2
midY := (q0Y + qY) / 2
path.QuadCurveTo(q0X+dx, q0Y+dy, midX+dx, midY+dy)
}
q0X, q0Y, on0 = qX, qY, on
}
// Close the curve.
if on0 {
path.LineTo(startX+dx, startY+dy)
} else {
path.QuadCurveTo(q0X+dx, q0Y+dy, startX+dx, startY+dy)
}
}
// FontExtents contains font metric information.
type FontExtents struct {
// Ascent is the distance that the text
// extends above the baseline.
Ascent float64
// Descent is the distance that the text
// extends below the baseline. The descent
// is given as a negative value.
Descent float64
// Height is the distance from the lowest
// descending point to the highest ascending
// point.
Height float64
}
// Extents returns the FontExtents for a font.
// TODO needs to read this https://developer.apple.com/fonts/TrueType-Reference-Manual/RM02/Chap2.html#intro
func Extents(font *truetype.Font, size float64) FontExtents {
bounds := font.Bounds(fixed.Int26_6(font.FUnitsPerEm()))
scale := size / float64(font.FUnitsPerEm())
return FontExtents{
Ascent: float64(bounds.Max.Y) * scale,
Descent: float64(bounds.Min.Y) * scale,
Height: float64(bounds.Max.Y-bounds.Min.Y) * scale,
}
}
// Copyright 2010 The draw2d Authors. All rights reserved.
// created: 13/12/2010 by Laurent Le Goff
package drawing
// Transformer apply the Matrix transformation tr
type Transformer struct {
Tr Matrix
Flattener Flattener
}
// MoveTo implements the path builder interface.
func (t Transformer) MoveTo(x, y float64) {
u := x*t.Tr[0] + y*t.Tr[2] + t.Tr[4]
v := x*t.Tr[1] + y*t.Tr[3] + t.Tr[5]
t.Flattener.MoveTo(u, v)
}
// LineTo implements the path builder interface.
func (t Transformer) LineTo(x, y float64) {
u := x*t.Tr[0] + y*t.Tr[2] + t.Tr[4]
v := x*t.Tr[1] + y*t.Tr[3] + t.Tr[5]
t.Flattener.LineTo(u, v)
}
// LineJoin implements the path builder interface.
func (t Transformer) LineJoin() {
t.Flattener.LineJoin()
}
// Close implements the path builder interface.
func (t Transformer) Close() {
t.Flattener.Close()
}
// End implements the path builder interface.
func (t Transformer) End() {
t.Flattener.End()
}
package drawing
import (
"math"
"golang.org/x/image/math/fixed"
"github.com/golang/freetype/raster"
"github.com/golang/freetype/truetype"
)
// PixelsToPoints returns the points for a given number of pixels at a DPI.
func PixelsToPoints(dpi, pixels float64) (points float64) {
points = (pixels * 72.0) / dpi
return
}
// PointsToPixels returns the pixels for a given number of points at a DPI.
func PointsToPixels(dpi, points float64) (pixels float64) {
pixels = (points * dpi) / 72.0
return
}
func abs(i int) int {
if i < 0 {
return -i
}
return i
}
func distance(x1, y1, x2, y2 float64) float64 {
return vectorDistance(x2-x1, y2-y1)
}
func vectorDistance(dx, dy float64) float64 {
return float64(math.Sqrt(dx*dx + dy*dy))
}
func toFtCap(c LineCap) raster.Capper {
switch c {
case RoundCap:
return raster.RoundCapper
case ButtCap:
return raster.ButtCapper
case SquareCap:
return raster.SquareCapper
}
return raster.RoundCapper
}
func toFtJoin(j LineJoin) raster.Joiner {
switch j {
case RoundJoin:
return raster.RoundJoiner
case BevelJoin:
return raster.BevelJoiner
}
return raster.RoundJoiner
}
func pointToF64Point(p truetype.Point) (x, y float64) {
return fUnitsToFloat64(p.X), -fUnitsToFloat64(p.Y)
}
func fUnitsToFloat64(x fixed.Int26_6) float64 {
scaled := x << 2
return float64(scaled/256) + float64(scaled%256)/256.0
}
package chart
import "fmt"
const (
// DefaultEMAPeriod is the default EMA period used in the sigma calculation.
DefaultEMAPeriod = 12
)
// Interface Assertions.
var (
_ Series = (*EMASeries)(nil)
_ FirstValuesProvider = (*EMASeries)(nil)
_ LastValuesProvider = (*EMASeries)(nil)
)
// EMASeries is a computed series.
type EMASeries struct {
Name string
Style Style
YAxis YAxisType
Period int
InnerSeries ValuesProvider
cache []float64
}
// GetName returns the name of the time series.
func (ema EMASeries) GetName() string {
return ema.Name
}
// GetStyle returns the line style.
func (ema EMASeries) GetStyle() Style {
return ema.Style
}
// GetYAxis returns which YAxis the series draws on.
func (ema EMASeries) GetYAxis() YAxisType {
return ema.YAxis
}
// GetPeriod returns the window size.
func (ema EMASeries) GetPeriod() int {
if ema.Period == 0 {
return DefaultEMAPeriod
}
return ema.Period
}
// Len returns the number of elements in the series.
func (ema EMASeries) Len() int {
return ema.InnerSeries.Len()
}
// GetSigma returns the smoothing factor for the serise.
func (ema EMASeries) GetSigma() float64 {
return 2.0 / (float64(ema.GetPeriod()) + 1)
}
// GetValues gets a value at a given index.
func (ema *EMASeries) GetValues(index int) (x, y float64) {
if ema.InnerSeries == nil {
return
}
if len(ema.cache) == 0 {
ema.ensureCachedValues()
}
vx, _ := ema.InnerSeries.GetValues(index)
x = vx
y = ema.cache[index]
return
}
// GetFirstValues computes the first moving average value.
func (ema *EMASeries) GetFirstValues() (x, y float64) {
if ema.InnerSeries == nil {
return
}
if len(ema.cache) == 0 {
ema.ensureCachedValues()
}
x, _ = ema.InnerSeries.GetValues(0)
y = ema.cache[0]
return
}
// GetLastValues computes the last moving average value but walking back window size samples,
// and recomputing the last moving average chunk.
func (ema *EMASeries) GetLastValues() (x, y float64) {
if ema.InnerSeries == nil {
return
}
if len(ema.cache) == 0 {
ema.ensureCachedValues()
}
lastIndex := ema.InnerSeries.Len() - 1
x, _ = ema.InnerSeries.GetValues(lastIndex)
y = ema.cache[lastIndex]
return
}
func (ema *EMASeries) ensureCachedValues() {
seriesLength := ema.InnerSeries.Len()
ema.cache = make([]float64, seriesLength)
sigma := ema.GetSigma()
for x := 0; x < seriesLength; x++ {
_, y := ema.InnerSeries.GetValues(x)
if x == 0 {
ema.cache[x] = y
continue
}
previousEMA := ema.cache[x-1]
ema.cache[x] = ((y - previousEMA) * sigma) + previousEMA
}
}
// Render renders the series.
func (ema *EMASeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) {
style := ema.Style.InheritFrom(defaults)
Draw.LineSeries(r, canvasBox, xrange, yrange, style, ema)
}
// Validate validates the series.
func (ema *EMASeries) Validate() error {
if ema.InnerSeries == nil {
return fmt.Errorf("ema series requires InnerSeries to be set")
}
return nil
}
package chart
import "fmt"
// FirstValueAnnotation returns an annotation series of just the first value of a value provider as an annotation.
func FirstValueAnnotation(innerSeries ValuesProvider, vfs ...ValueFormatter) AnnotationSeries {
var vf ValueFormatter
if len(vfs) > 0 {
vf = vfs[0]
} else if typed, isTyped := innerSeries.(ValueFormatterProvider); isTyped {
_, vf = typed.GetValueFormatters()
} else {
vf = FloatValueFormatter
}
var firstValue Value2
if typed, isTyped := innerSeries.(FirstValuesProvider); isTyped {
firstValue.XValue, firstValue.YValue = typed.GetFirstValues()
firstValue.Label = vf(firstValue.YValue)
} else {
firstValue.XValue, firstValue.YValue = innerSeries.GetValues(0)
firstValue.Label = vf(firstValue.YValue)
}
var seriesName string
var seriesStyle Style
if typed, isTyped := innerSeries.(Series); isTyped {
seriesName = fmt.Sprintf("%s - First Value", typed.GetName())
seriesStyle = typed.GetStyle()
}
return AnnotationSeries{
Name: seriesName,
Style: seriesStyle,
Annotations: []Value2{firstValue},
}
}
package chart
import (
"sync"
"github.com/golang/freetype/truetype"
"github.com/wcharczuk/go-chart/roboto"
)
var (
_defaultFontLock sync.Mutex
_defaultFont *truetype.Font
)
// GetDefaultFont returns the default font (Roboto-Medium).
func GetDefaultFont() (*truetype.Font, error) {
if _defaultFont == nil {
_defaultFontLock.Lock()
defer _defaultFontLock.Unlock()
if _defaultFont == nil {
font, err := truetype.Parse(roboto.Roboto)
if err != nil {
return nil, err
}
_defaultFont = font
}
}
return _defaultFont, nil
}
package chart
// GridLineProvider is a type that provides grid lines.
type GridLineProvider interface {
GetGridLines(ticks []Tick, isVertical bool, majorStyle, minorStyle Style) []GridLine
}
// GridLine is a line on a graph canvas.
type GridLine struct {
IsMinor bool
Style Style
Value float64
}
// Major returns if the gridline is a `major` line.
func (gl GridLine) Major() bool {
return !gl.IsMinor
}
// Minor returns if the gridline is a `minor` line.
func (gl GridLine) Minor() bool {
return gl.IsMinor
}
// Render renders the gridline
func (gl GridLine) Render(r Renderer, canvasBox Box, ra Range, isVertical bool, defaults Style) {
r.SetStrokeColor(gl.Style.GetStrokeColor(defaults.GetStrokeColor()))
r.SetStrokeWidth(gl.Style.GetStrokeWidth(defaults.GetStrokeWidth()))
r.SetStrokeDashArray(gl.Style.GetStrokeDashArray(defaults.GetStrokeDashArray()))
if isVertical {
lineLeft := canvasBox.Left + ra.Translate(gl.Value)
lineBottom := canvasBox.Bottom
lineTop := canvasBox.Top
r.MoveTo(lineLeft, lineBottom)
r.LineTo(lineLeft, lineTop)
r.Stroke()
} else {
lineLeft := canvasBox.Left
lineRight := canvasBox.Right
lineHeight := canvasBox.Bottom - ra.Translate(gl.Value)
r.MoveTo(lineLeft, lineHeight)
r.LineTo(lineRight, lineHeight)
r.Stroke()
}
}
// GenerateGridLines generates grid lines.
func GenerateGridLines(ticks []Tick, majorStyle, minorStyle Style) []GridLine {
var gl []GridLine
isMinor := false
if len(ticks) < 3 {
return gl
}
for _, t := range ticks[1 : len(ticks)-1] {
s := majorStyle
if isMinor {
s = minorStyle
}
gl = append(gl, GridLine{
Style: s,
IsMinor: isMinor,
Value: t.Value,
})
isMinor = !isMinor
}
return gl
}
package chart
import "fmt"
// HistogramSeries is a special type of series that draws as a histogram.
// Some peculiarities; it will always be lower bounded at 0 (at the very least).
// This may alter ranges a bit and generally you want to put a histogram series on it's own y-axis.
type HistogramSeries struct {
Name string
Style Style
YAxis YAxisType
InnerSeries ValuesProvider
}
// GetName implements Series.GetName.
func (hs HistogramSeries) GetName() string {
return hs.Name
}
// GetStyle implements Series.GetStyle.
func (hs HistogramSeries) GetStyle() Style {
return hs.Style
}
// GetYAxis returns which yaxis the series is mapped to.
func (hs HistogramSeries) GetYAxis() YAxisType {
return hs.YAxis
}
// Len implements BoundedValuesProvider.Len.
func (hs HistogramSeries) Len() int {
return hs.InnerSeries.Len()
}
// GetValues implements ValuesProvider.GetValues.
func (hs HistogramSeries) GetValues(index int) (x, y float64) {
return hs.InnerSeries.GetValues(index)
}
// GetBoundedValues implements BoundedValuesProvider.GetBoundedValue
func (hs HistogramSeries) GetBoundedValues(index int) (x, y1, y2 float64) {
vx, vy := hs.InnerSeries.GetValues(index)
x = vx
if vy > 0 {
y1 = vy
return
}
y2 = vy
return
}
// Render implements Series.Render.
func (hs HistogramSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) {
style := hs.Style.InheritFrom(defaults)
Draw.HistogramSeries(r, canvasBox, xrange, yrange, style, hs)
}
// Validate validates the series.
func (hs HistogramSeries) Validate() error {
if hs.InnerSeries == nil {
return fmt.Errorf("histogram series requires InnerSeries to be set")
}
return nil
}
package chart
import (
"bytes"
"errors"
"image"
"image/png"
)
// RGBACollector is a render target for a chart.
type RGBACollector interface {
SetRGBA(i *image.RGBA)
}
// ImageWriter is a special type of io.Writer that produces a final image.
type ImageWriter struct {
rgba *image.RGBA
contents *bytes.Buffer
}
func (ir *ImageWriter) Write(buffer []byte) (int, error) {
if ir.contents == nil {
ir.contents = bytes.NewBuffer([]byte{})
}
return ir.contents.Write(buffer)
}
// SetRGBA sets a raw version of the image.
func (ir *ImageWriter) SetRGBA(i *image.RGBA) {
ir.rgba = i
}
// Image returns an *image.Image for the result.
func (ir *ImageWriter) Image() (image.Image, error) {
if ir.rgba != nil {
return ir.rgba, nil
}
if ir.contents != nil && ir.contents.Len() > 0 {
return png.Decode(ir.contents)
}
return nil, errors.New("no valid sources for image data, cannot continue")
}
package chart
import "github.com/wcharczuk/go-chart/drawing"
// Jet is a color map provider based on matlab's jet color map.
func Jet(v, vmin, vmax float64) drawing.Color {
c := drawing.Color{R: 0xff, G: 0xff, B: 0xff, A: 0xff} // white
var dv float64
if v < vmin {
v = vmin
}
if v > vmax {
v = vmax
}
dv = vmax - vmin
if v < (vmin + 0.25*dv) {
c.R = 0
c.G = drawing.ColorChannelFromFloat(4 * (v - vmin) / dv)
} else if v < (vmin + 0.5*dv) {
c.R = 0
c.B = drawing.ColorChannelFromFloat(1 + 4*(vmin+0.25*dv-v)/dv)
} else if v < (vmin + 0.75*dv) {
c.R = drawing.ColorChannelFromFloat(4 * (v - vmin - 0.5*dv) / dv)
c.B = 0
} else {
c.G = drawing.ColorChannelFromFloat(1 + 4*(vmin+0.75*dv-v)/dv)
c.B = 0
}
return c
}
package chart
import "fmt"
// LastValueAnnotation returns an annotation series of just the last value of a value provider.
func LastValueAnnotation(innerSeries ValuesProvider, vfs ...ValueFormatter) AnnotationSeries {
var vf ValueFormatter
if len(vfs) > 0 {
vf = vfs[0]
} else if typed, isTyped := innerSeries.(ValueFormatterProvider); isTyped {
_, vf = typed.GetValueFormatters()
} else {
vf = FloatValueFormatter
}
var lastValue Value2
if typed, isTyped := innerSeries.(LastValuesProvider); isTyped {
lastValue.XValue, lastValue.YValue = typed.GetLastValues()
lastValue.Label = vf(lastValue.YValue)
} else {
lastValue.XValue, lastValue.YValue = innerSeries.GetValues(innerSeries.Len() - 1)
lastValue.Label = vf(lastValue.YValue)
}
var seriesName string
var seriesStyle Style
if typed, isTyped := innerSeries.(Series); isTyped {
seriesName = fmt.Sprintf("%s - Last Value", typed.GetName())
seriesStyle = typed.GetStyle()
}
return AnnotationSeries{
Name: seriesName,
Style: seriesStyle,
Annotations: []Value2{lastValue},
}
}
package chart
import (
"github.com/wcharczuk/go-chart/drawing"
"github.com/wcharczuk/go-chart/util"
)
// Legend returns a legend renderable function.
func Legend(c *Chart, userDefaults ...Style) Renderable {
return func(r Renderer, cb Box, chartDefaults Style) {
legendDefaults := Style{
FillColor: drawing.ColorWhite,
FontColor: DefaultTextColor,
FontSize: 8.0,
StrokeColor: DefaultAxisColor,
StrokeWidth: DefaultAxisLineWidth,
}
var legendStyle Style
if len(userDefaults) > 0 {
legendStyle = userDefaults[0].InheritFrom(chartDefaults.InheritFrom(legendDefaults))
} else {
legendStyle = chartDefaults.InheritFrom(legendDefaults)
}
// DEFAULTS
legendPadding := Box{
Top: 5,
Left: 5,
Right: 5,
Bottom: 5,
}
lineTextGap := 5
lineLengthMinimum := 25
var labels []string
var lines []Style
for index, s := range c.Series {
if s.GetStyle().IsZero() || s.GetStyle().Show {
if _, isAnnotationSeries := s.(AnnotationSeries); !isAnnotationSeries {
labels = append(labels, s.GetName())
lines = append(lines, s.GetStyle().InheritFrom(c.styleDefaultsSeries(index)))
}
}
}
legend := Box{
Top: cb.Top,
Left: cb.Left,
// bottom and right will be sized by the legend content + relevant padding.
}
legendContent := Box{
Top: legend.Top + legendPadding.Top,
Left: legend.Left + legendPadding.Left,
Right: legend.Left + legendPadding.Left,
Bottom: legend.Top + legendPadding.Top,
}
legendStyle.GetTextOptions().WriteToRenderer(r)
// measure
labelCount := 0
for x := 0; x < len(labels); x++ {
if len(labels[x]) > 0 {
tb := r.MeasureText(labels[x])
if labelCount > 0 {
legendContent.Bottom += DefaultMinimumTickVerticalSpacing
}
legendContent.Bottom += tb.Height()
right := legendContent.Left + tb.Width() + lineTextGap + lineLengthMinimum
legendContent.Right = util.Math.MaxInt(legendContent.Right, right)
labelCount++
}
}
legend = legend.Grow(legendContent)
legend.Right = legendContent.Right + legendPadding.Right
legend.Bottom = legendContent.Bottom + legendPadding.Bottom
Draw.Box(r, legend, legendStyle)
legendStyle.GetTextOptions().WriteToRenderer(r)
ycursor := legendContent.Top
tx := legendContent.Left
legendCount := 0
var label string
for x := 0; x < len(labels); x++ {
label = labels[x]
if len(label) > 0 {
if legendCount > 0 {
ycursor += DefaultMinimumTickVerticalSpacing
}
tb := r.MeasureText(label)
ty := ycursor + tb.Height()
r.Text(label, tx, ty)
th2 := tb.Height() >> 1
lx := tx + tb.Width() + lineTextGap
ly := ty - th2
lx2 := legendContent.Right - legendPadding.Right
r.SetStrokeColor(lines[x].GetStrokeColor())
r.SetStrokeWidth(lines[x].GetStrokeWidth())
r.SetStrokeDashArray(lines[x].GetStrokeDashArray())
r.MoveTo(lx, ly)
r.LineTo(lx2, ly)
r.Stroke()
ycursor += tb.Height()
legendCount++
}
}
}
}
// LegendThin is a legend that doesn't obscure the chart area.
func LegendThin(c *Chart, userDefaults ...Style) Renderable {
return func(r Renderer, cb Box, chartDefaults Style) {
legendDefaults := Style{
FillColor: drawing.ColorWhite,
FontColor: DefaultTextColor,
FontSize: 8.0,
StrokeColor: DefaultAxisColor,
StrokeWidth: DefaultAxisLineWidth,
Padding: Box{
Top: 2,
Left: 7,
Right: 7,
Bottom: 5,
},
}
var legendStyle Style
if len(userDefaults) > 0 {
legendStyle = userDefaults[0].InheritFrom(chartDefaults.InheritFrom(legendDefaults))
} else {
legendStyle = chartDefaults.InheritFrom(legendDefaults)
}
r.SetFont(legendStyle.GetFont())
r.SetFontColor(legendStyle.GetFontColor())
r.SetFontSize(legendStyle.GetFontSize())
var labels []string
var lines []Style
for index, s := range c.Series {
if s.GetStyle().IsZero() || s.GetStyle().Show {
if _, isAnnotationSeries := s.(AnnotationSeries); !isAnnotationSeries {
labels = append(labels, s.GetName())
lines = append(lines, s.GetStyle().InheritFrom(c.styleDefaultsSeries(index)))
}
}
}
var textHeight int
var textWidth int
var textBox Box
for x := 0; x < len(labels); x++ {
if len(labels[x]) > 0 {
textBox = r.MeasureText(labels[x])
textHeight = util.Math.MaxInt(textBox.Height(), textHeight)
textWidth = util.Math.MaxInt(textBox.Width(), textWidth)
}
}
legendBoxHeight := textHeight + legendStyle.Padding.Top + legendStyle.Padding.Bottom
chartPadding := cb.Top
legendYMargin := (chartPadding - legendBoxHeight) >> 1
legendBox := Box{
Left: cb.Left,
Right: cb.Right,
Top: legendYMargin,
Bottom: legendYMargin + legendBoxHeight,
}
Draw.Box(r, legendBox, legendDefaults)
r.SetFont(legendStyle.GetFont())
r.SetFontColor(legendStyle.GetFontColor())
r.SetFontSize(legendStyle.GetFontSize())
lineTextGap := 5
lineLengthMinimum := 25
tx := legendBox.Left + legendStyle.Padding.Left
ty := legendYMargin + legendStyle.Padding.Top + textHeight
var label string
var lx, ly int
th2 := textHeight >> 1
for index := range labels {
label = labels[index]
if len(label) > 0 {
textBox = r.MeasureText(label)
r.Text(label, tx, ty)
lx = tx + textBox.Width() + lineTextGap
ly = ty - th2
r.SetStrokeColor(lines[index].GetStrokeColor())
r.SetStrokeWidth(lines[index].GetStrokeWidth())
r.SetStrokeDashArray(lines[index].GetStrokeDashArray())
r.MoveTo(lx, ly)
r.LineTo(lx+lineLengthMinimum, ly)
r.Stroke()
tx += textBox.Width() + DefaultMinimumTickHorizontalSpacing + lineTextGap + lineLengthMinimum
}
}
}
}
// LegendLeft is a legend that is designed for longer series lists.
func LegendLeft(c *Chart, userDefaults ...Style) Renderable {
return func(r Renderer, cb Box, chartDefaults Style) {
legendDefaults := Style{
FillColor: drawing.ColorWhite,
FontColor: DefaultTextColor,
FontSize: 8.0,
StrokeColor: DefaultAxisColor,
StrokeWidth: DefaultAxisLineWidth,
}
var legendStyle Style
if len(userDefaults) > 0 {
legendStyle = userDefaults[0].InheritFrom(chartDefaults.InheritFrom(legendDefaults))
} else {
legendStyle = chartDefaults.InheritFrom(legendDefaults)
}
// DEFAULTS
legendPadding := Box{
Top: 5,
Left: 5,
Right: 5,
Bottom: 5,
}
lineTextGap := 5
lineLengthMinimum := 25
var labels []string
var lines []Style
for index, s := range c.Series {
if s.GetStyle().IsZero() || s.GetStyle().Show {
if _, isAnnotationSeries := s.(AnnotationSeries); !isAnnotationSeries {
labels = append(labels, s.GetName())
lines = append(lines, s.GetStyle().InheritFrom(c.styleDefaultsSeries(index)))
}
}
}
legend := Box{
Top: 5,
Left: 5,
// bottom and right will be sized by the legend content + relevant padding.
}
legendContent := Box{
Top: legend.Top + legendPadding.Top,
Left: legend.Left + legendPadding.Left,
Right: legend.Left + legendPadding.Left,
Bottom: legend.Top + legendPadding.Top,
}
legendStyle.GetTextOptions().WriteToRenderer(r)
// measure
labelCount := 0
for x := 0; x < len(labels); x++ {
if len(labels[x]) > 0 {
tb := r.MeasureText(labels[x])
if labelCount > 0 {
legendContent.Bottom += DefaultMinimumTickVerticalSpacing
}
legendContent.Bottom += tb.Height()
right := legendContent.Left + tb.Width() + lineTextGap + lineLengthMinimum
legendContent.Right = util.Math.MaxInt(legendContent.Right, right)
labelCount++
}
}
legend = legend.Grow(legendContent)
legend.Right = legendContent.Right + legendPadding.Right
legend.Bottom = legendContent.Bottom + legendPadding.Bottom
Draw.Box(r, legend, legendStyle)
legendStyle.GetTextOptions().WriteToRenderer(r)
ycursor := legendContent.Top
tx := legendContent.Left
legendCount := 0
var label string
for x := 0; x < len(labels); x++ {
label = labels[x]
if len(label) > 0 {
if legendCount > 0 {
ycursor += DefaultMinimumTickVerticalSpacing
}
tb := r.MeasureText(label)
ty := ycursor + tb.Height()
r.Text(label, tx, ty)
th2 := tb.Height() >> 1
lx := tx + tb.Width() + lineTextGap
ly := ty - th2
lx2 := legendContent.Right - legendPadding.Right
r.SetStrokeColor(lines[x].GetStrokeColor())
r.SetStrokeWidth(lines[x].GetStrokeWidth())
r.SetStrokeDashArray(lines[x].GetStrokeDashArray())
r.MoveTo(lx, ly)
r.LineTo(lx2, ly)
r.Stroke()
ycursor += tb.Height()
legendCount++
}
}
}
}
package chart
// LinearCoefficientProvider is a type that returns linear cofficients.
type LinearCoefficientProvider interface {
Coefficients() (m, b, stdev, avg float64)
}
// LinearCoefficients returns a fixed linear coefficient pair.
func LinearCoefficients(m, b float64) LinearCoefficientSet {
return LinearCoefficientSet{
M: m,
B: b,
}
}
// NormalizedLinearCoefficients returns a fixed linear coefficient pair.
func NormalizedLinearCoefficients(m, b, stdev, avg float64) LinearCoefficientSet {
return LinearCoefficientSet{
M: m,
B: b,
StdDev: stdev,
Avg: avg,
}
}
// LinearCoefficientSet is the m and b values for the linear equation in the form:
// y = (m*x) + b
type LinearCoefficientSet struct {
M float64
B float64
StdDev float64
Avg float64
}
// Coefficients returns the coefficients.
func (lcs LinearCoefficientSet) Coefficients() (m, b, stdev, avg float64) {
m = lcs.M
b = lcs.B
stdev = lcs.StdDev
avg = lcs.Avg
return
}
package chart
import (
"fmt"
"github.com/wcharczuk/go-chart/seq"
util "github.com/wcharczuk/go-chart/util"
)
// Interface Assertions.
var (
_ Series = (*LinearRegressionSeries)(nil)
_ FirstValuesProvider = (*LinearRegressionSeries)(nil)
_ LastValuesProvider = (*LinearRegressionSeries)(nil)
_ LinearCoefficientProvider = (*LinearRegressionSeries)(nil)
)
// LinearRegressionSeries is a series that plots the n-nearest neighbors
// linear regression for the values.
type LinearRegressionSeries struct {
Name string
Style Style
YAxis YAxisType
Limit int
Offset int
InnerSeries ValuesProvider
m float64
b float64
avgx float64
stddevx float64
}
// Coefficients returns the linear coefficients for the series.
func (lrs LinearRegressionSeries) Coefficients() (m, b, stdev, avg float64) {
if lrs.IsZero() {
lrs.computeCoefficients()
}
m = lrs.m
b = lrs.b
stdev = lrs.stddevx
avg = lrs.avgx
return
}
// GetName returns the name of the time series.
func (lrs LinearRegressionSeries) GetName() string {
return lrs.Name
}
// GetStyle returns the line style.
func (lrs LinearRegressionSeries) GetStyle() Style {
return lrs.Style
}
// GetYAxis returns which YAxis the series draws on.
func (lrs LinearRegressionSeries) GetYAxis() YAxisType {
return lrs.YAxis
}
// Len returns the number of elements in the series.
func (lrs LinearRegressionSeries) Len() int {
return util.Math.MinInt(lrs.GetLimit(), lrs.InnerSeries.Len()-lrs.GetOffset())
}
// GetLimit returns the window size.
func (lrs LinearRegressionSeries) GetLimit() int {
if lrs.Limit == 0 {
return lrs.InnerSeries.Len()
}
return lrs.Limit
}
// GetEndIndex returns the effective limit end.
func (lrs LinearRegressionSeries) GetEndIndex() int {
windowEnd := lrs.GetOffset() + lrs.GetLimit()
innerSeriesLastIndex := lrs.InnerSeries.Len() - 1
return util.Math.MinInt(windowEnd, innerSeriesLastIndex)
}
// GetOffset returns the data offset.
func (lrs LinearRegressionSeries) GetOffset() int {
if lrs.Offset == 0 {
return 0
}
return lrs.Offset
}
// GetValues gets a value at a given index.
func (lrs *LinearRegressionSeries) GetValues(index int) (x, y float64) {
if lrs.InnerSeries == nil || lrs.InnerSeries.Len() == 0 {
return
}
if lrs.IsZero() {
lrs.computeCoefficients()
}
offset := lrs.GetOffset()
effectiveIndex := util.Math.MinInt(index+offset, lrs.InnerSeries.Len())
x, y = lrs.InnerSeries.GetValues(effectiveIndex)
y = (lrs.m * lrs.normalize(x)) + lrs.b
return
}
// GetFirstValues computes the first linear regression value.
func (lrs *LinearRegressionSeries) GetFirstValues() (x, y float64) {
if lrs.InnerSeries == nil || lrs.InnerSeries.Len() == 0 {
return
}
if lrs.IsZero() {
lrs.computeCoefficients()
}
x, y = lrs.InnerSeries.GetValues(0)
y = (lrs.m * lrs.normalize(x)) + lrs.b
return
}
// GetLastValues computes the last linear regression value.
func (lrs *LinearRegressionSeries) GetLastValues() (x, y float64) {
if lrs.InnerSeries == nil || lrs.InnerSeries.Len() == 0 {
return
}
if lrs.IsZero() {
lrs.computeCoefficients()
}
endIndex := lrs.GetEndIndex()
x, y = lrs.InnerSeries.GetValues(endIndex)
y = (lrs.m * lrs.normalize(x)) + lrs.b
return
}
// Render renders the series.
func (lrs *LinearRegressionSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) {
style := lrs.Style.InheritFrom(defaults)
Draw.LineSeries(r, canvasBox, xrange, yrange, style, lrs)
}
// Validate validates the series.
func (lrs *LinearRegressionSeries) Validate() error {
if lrs.InnerSeries == nil {
return fmt.Errorf("linear regression series requires InnerSeries to be set")
}
return nil
}
// IsZero returns if we've computed the coefficients or not.
func (lrs *LinearRegressionSeries) IsZero() bool {
return lrs.m == 0 && lrs.b == 0
}
//
// internal helpers
//
func (lrs *LinearRegressionSeries) normalize(xvalue float64) float64 {
return (xvalue - lrs.avgx) / lrs.stddevx
}
// computeCoefficients computes the `m` and `b` terms in the linear formula given by `y = mx+b`.
func (lrs *LinearRegressionSeries) computeCoefficients() {
startIndex := lrs.GetOffset()
endIndex := lrs.GetEndIndex()
p := float64(endIndex - startIndex)
xvalues := seq.NewBufferWithCapacity(lrs.Len())
for index := startIndex; index < endIndex; index++ {
x, _ := lrs.InnerSeries.GetValues(index)
xvalues.Enqueue(x)
}
lrs.avgx = seq.Seq{Provider: xvalues}.Average()
lrs.stddevx = seq.Seq{Provider: xvalues}.StdDev()
var sumx, sumy, sumxx, sumxy float64
for index := startIndex; index < endIndex; index++ {
x, y := lrs.InnerSeries.GetValues(index)
x = lrs.normalize(x)
sumx += x
sumy += y
sumxx += x * x
sumxy += x * y
}
lrs.m = (p*sumxy - sumx*sumy) / (p*sumxx - sumx*sumx)
lrs.b = (sumy / p) - (lrs.m * sumx / p)
}
package chart
import (
"fmt"
)
// Interface Assertions.
var (
_ Series = (*LinearSeries)(nil)
_ FirstValuesProvider = (*LinearSeries)(nil)
_ LastValuesProvider = (*LinearSeries)(nil)
)
// LinearSeries is a series that plots a line in a given domain.
type LinearSeries struct {
Name string
Style Style
YAxis YAxisType
XValues []float64
InnerSeries LinearCoefficientProvider
m float64
b float64
stdev float64
avg float64
}
// GetName returns the name of the time series.
func (ls LinearSeries) GetName() string {
return ls.Name
}
// GetStyle returns the line style.
func (ls LinearSeries) GetStyle() Style {
return ls.Style
}
// GetYAxis returns which YAxis the series draws on.
func (ls LinearSeries) GetYAxis() YAxisType {
return ls.YAxis
}
// Len returns the number of elements in the series.
func (ls LinearSeries) Len() int {
return len(ls.XValues)
}
// GetEndIndex returns the effective limit end.
func (ls LinearSeries) GetEndIndex() int {
return len(ls.XValues) - 1
}
// GetValues gets a value at a given index.
func (ls *LinearSeries) GetValues(index int) (x, y float64) {
if ls.InnerSeries == nil || len(ls.XValues) == 0 {
return
}
if ls.IsZero() {
ls.computeCoefficients()
}
x = ls.XValues[index]
y = (ls.m * ls.normalize(x)) + ls.b
return
}
// GetFirstValues computes the first linear regression value.
func (ls *LinearSeries) GetFirstValues() (x, y float64) {
if ls.InnerSeries == nil || len(ls.XValues) == 0 {
return
}
if ls.IsZero() {
ls.computeCoefficients()
}
x, y = ls.GetValues(0)
return
}
// GetLastValues computes the last linear regression value.
func (ls *LinearSeries) GetLastValues() (x, y float64) {
if ls.InnerSeries == nil || len(ls.XValues) == 0 {
return
}
if ls.IsZero() {
ls.computeCoefficients()
}
x, y = ls.GetValues(ls.GetEndIndex())
return
}
// Render renders the series.
func (ls *LinearSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) {
Draw.LineSeries(r, canvasBox, xrange, yrange, ls.Style.InheritFrom(defaults), ls)
}
// Validate validates the series.
func (ls LinearSeries) Validate() error {
if ls.InnerSeries == nil {
return fmt.Errorf("linear regression series requires InnerSeries to be set")
}
return nil
}
// IsZero returns if the linear series has computed coefficients or not.
func (ls LinearSeries) IsZero() bool {
return ls.m == 0 && ls.b == 0
}
// computeCoefficients computes the `m` and `b` terms in the linear formula given by `y = mx+b`.
func (ls *LinearSeries) computeCoefficients() {
ls.m, ls.b, ls.stdev, ls.avg = ls.InnerSeries.Coefficients()
}
func (ls *LinearSeries) normalize(xvalue float64) float64 {
if ls.avg > 0 && ls.stdev > 0 {
return (xvalue - ls.avg) / ls.stdev
}
return xvalue
}
package chart
import "fmt"
const (
// DefaultMACDPeriodPrimary is the long window.
DefaultMACDPeriodPrimary = 26
// DefaultMACDPeriodSecondary is the short window.
DefaultMACDPeriodSecondary = 12
// DefaultMACDSignalPeriod is the signal period to compute for the MACD.
DefaultMACDSignalPeriod = 9
)
// MACDSeries computes the difference between the MACD line and the MACD Signal line.
// It is used in technical analysis and gives a lagging indicator of momentum.
type MACDSeries struct {
Name string
Style Style
YAxis YAxisType
InnerSeries ValuesProvider
PrimaryPeriod int
SecondaryPeriod int
SignalPeriod int
signal *MACDSignalSeries
macdl *MACDLineSeries
}
// Validate validates the series.
func (macd MACDSeries) Validate() error {
var err error
if macd.signal != nil {
err = macd.signal.Validate()
}
if err != nil {
return err
}
if macd.macdl != nil {
err = macd.macdl.Validate()
}
if err != nil {
return err
}
return nil
}
// GetPeriods returns the primary and secondary periods.
func (macd MACDSeries) GetPeriods() (w1, w2, sig int) {
if macd.PrimaryPeriod == 0 {
w1 = DefaultMACDPeriodPrimary
} else {
w1 = macd.PrimaryPeriod
}
if macd.SecondaryPeriod == 0 {
w2 = DefaultMACDPeriodSecondary
} else {
w2 = macd.SecondaryPeriod
}
if macd.SignalPeriod == 0 {
sig = DefaultMACDSignalPeriod
} else {
sig = macd.SignalPeriod
}
return
}
// GetName returns the name of the time series.
func (macd MACDSeries) GetName() string {
return macd.Name
}
// GetStyle returns the line style.
func (macd MACDSeries) GetStyle() Style {
return macd.Style
}
// GetYAxis returns which YAxis the series draws on.
func (macd MACDSeries) GetYAxis() YAxisType {
return macd.YAxis
}
// Len returns the number of elements in the series.
func (macd MACDSeries) Len() int {
if macd.InnerSeries == nil {
return 0
}
return macd.InnerSeries.Len()
}
// GetValues gets a value at a given index. For MACD it is the signal value.
func (macd *MACDSeries) GetValues(index int) (x float64, y float64) {
if macd.InnerSeries == nil {
return
}
if macd.signal == nil || macd.macdl == nil {
macd.ensureChildSeries()
}
_, lv := macd.macdl.GetValues(index)
_, sv := macd.signal.GetValues(index)
x, _ = macd.InnerSeries.GetValues(index)
y = lv - sv
return
}
func (macd *MACDSeries) ensureChildSeries() {
w1, w2, sig := macd.GetPeriods()
macd.signal = &MACDSignalSeries{
InnerSeries: macd.InnerSeries,
PrimaryPeriod: w1,
SecondaryPeriod: w2,
SignalPeriod: sig,
}
macd.macdl = &MACDLineSeries{
InnerSeries: macd.InnerSeries,
PrimaryPeriod: w1,
SecondaryPeriod: w2,
}
}
// MACDSignalSeries computes the EMA of the MACDLineSeries.
type MACDSignalSeries struct {
Name string
Style Style
YAxis YAxisType
InnerSeries ValuesProvider
PrimaryPeriod int
SecondaryPeriod int
SignalPeriod int
signal *EMASeries
}
// Validate validates the series.
func (macds MACDSignalSeries) Validate() error {
if macds.signal != nil {
return macds.signal.Validate()
}
return nil
}
// GetPeriods returns the primary and secondary periods.
func (macds MACDSignalSeries) GetPeriods() (w1, w2, sig int) {
if macds.PrimaryPeriod == 0 {
w1 = DefaultMACDPeriodPrimary
} else {
w1 = macds.PrimaryPeriod
}
if macds.SecondaryPeriod == 0 {
w2 = DefaultMACDPeriodSecondary
} else {
w2 = macds.SecondaryPeriod
}
if macds.SignalPeriod == 0 {
sig = DefaultMACDSignalPeriod
} else {
sig = macds.SignalPeriod
}
return
}
// GetName returns the name of the time series.
func (macds MACDSignalSeries) GetName() string {
return macds.Name
}
// GetStyle returns the line style.
func (macds MACDSignalSeries) GetStyle() Style {
return macds.Style
}
// GetYAxis returns which YAxis the series draws on.
func (macds MACDSignalSeries) GetYAxis() YAxisType {
return macds.YAxis
}
// Len returns the number of elements in the series.
func (macds *MACDSignalSeries) Len() int {
if macds.InnerSeries == nil {
return 0
}
return macds.InnerSeries.Len()
}
// GetValues gets a value at a given index. For MACD it is the signal value.
func (macds *MACDSignalSeries) GetValues(index int) (x float64, y float64) {
if macds.InnerSeries == nil {
return
}
if macds.signal == nil {
macds.ensureSignal()
}
x, _ = macds.InnerSeries.GetValues(index)
_, y = macds.signal.GetValues(index)
return
}
func (macds *MACDSignalSeries) ensureSignal() {
w1, w2, sig := macds.GetPeriods()
macds.signal = &EMASeries{
InnerSeries: &MACDLineSeries{
InnerSeries: macds.InnerSeries,
PrimaryPeriod: w1,
SecondaryPeriod: w2,
},
Period: sig,
}
}
// Render renders the series.
func (macds *MACDSignalSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) {
style := macds.Style.InheritFrom(defaults)
Draw.LineSeries(r, canvasBox, xrange, yrange, style, macds)
}
// MACDLineSeries is a series that computes the inner ema1-ema2 value as a series.
type MACDLineSeries struct {
Name string
Style Style
YAxis YAxisType
InnerSeries ValuesProvider
PrimaryPeriod int
SecondaryPeriod int
ema1 *EMASeries
ema2 *EMASeries
Sigma float64
}
// Validate validates the series.
func (macdl MACDLineSeries) Validate() error {
var err error
if macdl.ema1 != nil {
err = macdl.ema1.Validate()
}
if err != nil {
return err
}
if macdl.ema2 != nil {
err = macdl.ema2.Validate()
}
if err != nil {
return err
}
if macdl.InnerSeries == nil {
return fmt.Errorf("MACDLineSeries: must provide an inner series")
}
return nil
}
// GetName returns the name of the time series.
func (macdl MACDLineSeries) GetName() string {
return macdl.Name
}
// GetStyle returns the line style.
func (macdl MACDLineSeries) GetStyle() Style {
return macdl.Style
}
// GetYAxis returns which YAxis the series draws on.
func (macdl MACDLineSeries) GetYAxis() YAxisType {
return macdl.YAxis
}
// GetPeriods returns the primary and secondary periods.
func (macdl MACDLineSeries) GetPeriods() (w1, w2 int) {
if macdl.PrimaryPeriod == 0 {
w1 = DefaultMACDPeriodPrimary
} else {
w1 = macdl.PrimaryPeriod
}
if macdl.SecondaryPeriod == 0 {
w2 = DefaultMACDPeriodSecondary
} else {
w2 = macdl.SecondaryPeriod
}
return
}
// Len returns the number of elements in the series.
func (macdl *MACDLineSeries) Len() int {
if macdl.InnerSeries == nil {
return 0
}
return macdl.InnerSeries.Len()
}
// GetValues gets a value at a given index. For MACD it is the signal value.
func (macdl *MACDLineSeries) GetValues(index int) (x float64, y float64) {
if macdl.InnerSeries == nil {
return
}
if macdl.ema1 == nil && macdl.ema2 == nil {
macdl.ensureEMASeries()
}
x, _ = macdl.InnerSeries.GetValues(index)
_, emav1 := macdl.ema1.GetValues(index)
_, emav2 := macdl.ema2.GetValues(index)
y = emav2 - emav1
return
}
func (macdl *MACDLineSeries) ensureEMASeries() {
w1, w2 := macdl.GetPeriods()
macdl.ema1 = &EMASeries{
InnerSeries: macdl.InnerSeries,
Period: w1,
}
macdl.ema2 = &EMASeries{
InnerSeries: macdl.InnerSeries,
Period: w2,
}
}
// Render renders the series.
func (macdl *MACDLineSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) {
style := macdl.Style.InheritFrom(defaults)
Draw.LineSeries(r, canvasBox, xrange, yrange, style, macdl)
}
package matrix
import (
"bytes"
"errors"
"fmt"
"math"
)
const (
// DefaultEpsilon represents the minimum precision for matrix math operations.
DefaultEpsilon = 0.000001
)
var (
// ErrDimensionMismatch is a typical error.
ErrDimensionMismatch = errors.New("dimension mismatch")
// ErrSingularValue is a typical error.
ErrSingularValue = errors.New("singular value")
)
// New returns a new matrix.
func New(rows, cols int, values ...float64) *Matrix {
if len(values) == 0 {
return &Matrix{
stride: cols,
epsilon: DefaultEpsilon,
elements: make([]float64, rows*cols),
}
}
elems := make([]float64, rows*cols)
copy(elems, values)
return &Matrix{
stride: cols,
epsilon: DefaultEpsilon,
elements: elems,
}
}
// Identity returns the identity matrix of a given order.
func Identity(order int) *Matrix {
m := New(order, order)
for i := 0; i < order; i++ {
m.Set(i, i, 1)
}
return m
}
// Zero returns a matrix of a given size zeroed.
func Zero(rows, cols int) *Matrix {
return New(rows, cols)
}
// Ones returns an matrix of ones.
func Ones(rows, cols int) *Matrix {
ones := make([]float64, rows*cols)
for i := 0; i < (rows * cols); i++ {
ones[i] = 1
}
return &Matrix{
stride: cols,
epsilon: DefaultEpsilon,
elements: ones,
}
}
// Eye returns the eye matrix.
func Eye(n int) *Matrix {
m := Zero(n, n)
for i := 0; i < len(m.elements); i += n + 1 {
m.elements[i] = 1
}
return m
}
// NewFromArrays creates a matrix from a jagged array set.
func NewFromArrays(a [][]float64) *Matrix {
rows := len(a)
if rows == 0 {
return nil
}
cols := len(a[0])
m := New(rows, cols)
for row := 0; row < rows; row++ {
for col := 0; col < cols; col++ {
m.Set(row, col, a[row][col])
}
}
return m
}
// Matrix represents a 2d dense array of floats.
type Matrix struct {
epsilon float64
elements []float64
stride int
}
// String returns a string representation of the matrix.
func (m *Matrix) String() string {
buffer := bytes.NewBuffer(nil)
rows, cols := m.Size()
for row := 0; row < rows; row++ {
for col := 0; col < cols; col++ {
buffer.WriteString(f64s(m.Get(row, col)))
buffer.WriteRune(' ')
}
buffer.WriteRune('\n')
}
return buffer.String()
}
// Epsilon returns the maximum precision for math operations.
func (m *Matrix) Epsilon() float64 {
return m.epsilon
}
// WithEpsilon sets the epsilon on the matrix and returns a reference to the matrix.
func (m *Matrix) WithEpsilon(epsilon float64) *Matrix {
m.epsilon = epsilon
return m
}
// Each applies the action to each element of the matrix in
// rows => cols order.
func (m *Matrix) Each(action func(row, col int, value float64)) {
rows, cols := m.Size()
for row := 0; row < rows; row++ {
for col := 0; col < cols; col++ {
action(row, col, m.Get(row, col))
}
}
}
// Round rounds all the values in a matrix to it epsilon,
// returning a reference to the original
func (m *Matrix) Round() *Matrix {
rows, cols := m.Size()
for row := 0; row < rows; row++ {
for col := 0; col < cols; col++ {
m.Set(row, col, roundToEpsilon(m.Get(row, col), m.epsilon))
}
}
return m
}
// Arrays returns the matrix as a two dimensional jagged array.
func (m *Matrix) Arrays() [][]float64 {
rows, cols := m.Size()
a := make([][]float64, rows)
for row := 0; row < rows; row++ {
a[row] = make([]float64, cols)
for col := 0; col < cols; col++ {
a[row][col] = m.Get(row, col)
}
}
return a
}
// Size returns the dimensions of the matrix.
func (m *Matrix) Size() (rows, cols int) {
rows = len(m.elements) / m.stride
cols = m.stride
return
}
// IsSquare returns if the row count is equal to the column count.
func (m *Matrix) IsSquare() bool {
return m.stride == (len(m.elements) / m.stride)
}
// IsSymmetric returns if the matrix is symmetric about its diagonal.
func (m *Matrix) IsSymmetric() bool {
rows, cols := m.Size()
if rows != cols {
return false
}
for i := 0; i < rows; i++ {
for j := 0; j < i; j++ {
if m.Get(i, j) != m.Get(j, i) {
return false
}
}
}
return true
}
// Get returns the element at the given row, col.
func (m *Matrix) Get(row, col int) float64 {
index := (m.stride * row) + col
return m.elements[index]
}
// Set sets a value.
func (m *Matrix) Set(row, col int, val float64) {
index := (m.stride * row) + col
m.elements[index] = val
}
// Col returns a column of the matrix as a vector.
func (m *Matrix) Col(col int) Vector {
rows, _ := m.Size()
values := make([]float64, rows)
for row := 0; row < rows; row++ {
values[row] = m.Get(row, col)
}
return Vector(values)
}
// Row returns a row of the matrix as a vector.
func (m *Matrix) Row(row int) Vector {
_, cols := m.Size()
values := make([]float64, cols)
for col := 0; col < cols; col++ {
values[col] = m.Get(row, col)
}
return Vector(values)
}
// SubMatrix returns a sub matrix from a given outer matrix.
func (m *Matrix) SubMatrix(i, j, rows, cols int) *Matrix {
return &Matrix{
elements: m.elements[i*m.stride+j : i*m.stride+j+(rows-1)*m.stride+cols],
stride: m.stride,
epsilon: m.epsilon,
}
}
// ScaleRow applies a scale to an entire row.
func (m *Matrix) ScaleRow(row int, scale float64) {
startIndex := row * m.stride
for i := startIndex; i < m.stride; i++ {
m.elements[i] = m.elements[i] * scale
}
}
func (m *Matrix) scaleAddRow(rd int, rs int, f float64) {
indexd := rd * m.stride
indexs := rs * m.stride
for col := 0; col < m.stride; col++ {
m.elements[indexd] += f * m.elements[indexs]
indexd++
indexs++
}
}
// SwapRows swaps a row in the matrix in place.
func (m *Matrix) SwapRows(i, j int) {
var vi, vj float64
for col := 0; col < m.stride; col++ {
vi = m.Get(i, col)
vj = m.Get(j, col)
m.Set(i, col, vj)
m.Set(j, col, vi)
}
}
// Augment concatenates two matrices about the horizontal.
func (m *Matrix) Augment(m2 *Matrix) (*Matrix, error) {
mr, mc := m.Size()
m2r, m2c := m2.Size()
if mr != m2r {
return nil, ErrDimensionMismatch
}
m3 := Zero(mr, mc+m2c)
for row := 0; row < mr; row++ {
for col := 0; col < mc; col++ {
m3.Set(row, col, m.Get(row, col))
}
for col := 0; col < m2c; col++ {
m3.Set(row, mc+col, m2.Get(row, col))
}
}
return m3, nil
}
// Copy returns a duplicate of a given matrix.
func (m *Matrix) Copy() *Matrix {
m2 := &Matrix{stride: m.stride, epsilon: m.epsilon, elements: make([]float64, len(m.elements))}
copy(m2.elements, m.elements)
return m2
}
// DiagonalVector returns a vector from the diagonal of a matrix.
func (m *Matrix) DiagonalVector() Vector {
rows, cols := m.Size()
rank := minInt(rows, cols)
values := make([]float64, rank)
for index := 0; index < rank; index++ {
values[index] = m.Get(index, index)
}
return Vector(values)
}
// Diagonal returns a matrix from the diagonal of a matrix.
func (m *Matrix) Diagonal() *Matrix {
rows, cols := m.Size()
rank := minInt(rows, cols)
m2 := New(rank, rank)
for index := 0; index < rank; index++ {
m2.Set(index, index, m.Get(index, index))
}
return m2
}
// Equals returns if a matrix equals another matrix.
func (m *Matrix) Equals(other *Matrix) bool {
if other == nil && m != nil {
return false
} else if other == nil {
return true
}
if m.stride != other.stride {
return false
}
msize := len(m.elements)
m2size := len(other.elements)
if msize != m2size {
return false
}
for i := 0; i < msize; i++ {
if m.elements[i] != other.elements[i] {
return false
}
}
return true
}
// L returns the matrix with zeros below the diagonal.
func (m *Matrix) L() *Matrix {
rows, cols := m.Size()
m2 := New(rows, cols)
for row := 0; row < rows; row++ {
for col := row; col < cols; col++ {
m2.Set(row, col, m.Get(row, col))
}
}
return m2
}
// U returns the matrix with zeros above the diagonal.
// Does not include the diagonal.
func (m *Matrix) U() *Matrix {
rows, cols := m.Size()
m2 := New(rows, cols)
for row := 0; row < rows; row++ {
for col := 0; col < row && col < cols; col++ {
m2.Set(row, col, m.Get(row, col))
}
}
return m2
}
// math operations
// Multiply multiplies two matrices.
func (m *Matrix) Multiply(m2 *Matrix) (m3 *Matrix, err error) {
if m.stride*m2.stride != len(m2.elements) {
return nil, ErrDimensionMismatch
}
m3 = &Matrix{epsilon: m.epsilon, stride: m2.stride, elements: make([]float64, (len(m.elements)/m.stride)*m2.stride)}
for m1c0, m3x := 0, 0; m1c0 < len(m.elements); m1c0 += m.stride {
for m2r0 := 0; m2r0 < m2.stride; m2r0++ {
for m1x, m2x := m1c0, m2r0; m2x < len(m2.elements); m2x += m2.stride {
m3.elements[m3x] += m.elements[m1x] * m2.elements[m2x]
m1x++
}
m3x++
}
}
return
}
// Pivotize does something i'm not sure what.
func (m *Matrix) Pivotize() *Matrix {
pv := make([]int, m.stride)
for i := range pv {
pv[i] = i
}
for j, dx := 0, 0; j < m.stride; j++ {
row := j
max := m.elements[dx]
for i, ixcj := j, dx; i < m.stride; i++ {
if m.elements[ixcj] > max {
max = m.elements[ixcj]
row = i
}
ixcj += m.stride
}
if j != row {
pv[row], pv[j] = pv[j], pv[row]
}
dx += m.stride + 1
}
p := Zero(m.stride, m.stride)
for r, c := range pv {
p.elements[r*m.stride+c] = 1
}
return p
}
// Times returns the product of a matrix and another.
func (m *Matrix) Times(m2 *Matrix) (*Matrix, error) {
mr, mc := m.Size()
m2r, m2c := m2.Size()
if mc != m2r {
return nil, fmt.Errorf("cannot multiply (%dx%d) and (%dx%d)", mr, mc, m2r, m2c)
//return nil, ErrDimensionMismatch
}
c := Zero(mr, m2c)
for i := 0; i < mr; i++ {
sums := c.elements[i*c.stride : (i+1)*c.stride]
for k, a := range m.elements[i*m.stride : i*m.stride+m.stride] {
for j, b := range m2.elements[k*m2.stride : k*m2.stride+m2.stride] {
sums[j] += a * b
}
}
}
return c, nil
}
// Decompositions
// LU performs the LU decomposition.
func (m *Matrix) LU() (l, u, p *Matrix) {
l = Zero(m.stride, m.stride)
u = Zero(m.stride, m.stride)
p = m.Pivotize()
m, _ = p.Multiply(m)
for j, jxc0 := 0, 0; j < m.stride; j++ {
l.elements[jxc0+j] = 1
for i, ixc0 := 0, 0; ixc0 <= jxc0; i++ {
sum := 0.
for k, kxcj := 0, j; k < i; k++ {
sum += u.elements[kxcj] * l.elements[ixc0+k]
kxcj += m.stride
}
u.elements[ixc0+j] = m.elements[ixc0+j] - sum
ixc0 += m.stride
}
for ixc0 := jxc0; ixc0 < len(m.elements); ixc0 += m.stride {
sum := 0.
for k, kxcj := 0, j; k < j; k++ {
sum += u.elements[kxcj] * l.elements[ixc0+k]
kxcj += m.stride
}
l.elements[ixc0+j] = (m.elements[ixc0+j] - sum) / u.elements[jxc0+j]
}
jxc0 += m.stride
}
return
}
// QR performs the qr decomposition.
func (m *Matrix) QR() (q, r *Matrix) {
defer func() {
q = q.Round()
r = r.Round()
}()
rows, cols := m.Size()
qr := m.Copy()
q = New(rows, cols)
r = New(rows, cols)
var i, j, k int
var norm, s float64
for k = 0; k < cols; k++ {
norm = 0
for i = k; i < rows; i++ {
norm = math.Hypot(norm, qr.Get(i, k))
}
if norm != 0 {
if qr.Get(k, k) < 0 {
norm = -norm
}
for i = k; i < rows; i++ {
qr.Set(i, k, qr.Get(i, k)/norm)
}
qr.Set(k, k, qr.Get(k, k)+1.0)
for j = k + 1; j < cols; j++ {
s = 0
for i = k; i < rows; i++ {
s += qr.Get(i, k) * qr.Get(i, j)
}
s = -s / qr.Get(k, k)
for i = k; i < rows; i++ {
qr.Set(i, j, qr.Get(i, j)+s*qr.Get(i, k))
if i < j {
r.Set(i, j, qr.Get(i, j))
}
}
}
}
r.Set(k, k, -norm)
}
//Q Matrix:
i, j, k = 0, 0, 0
for k = cols - 1; k >= 0; k-- {
q.Set(k, k, 1.0)
for j = k; j < cols; j++ {
if qr.Get(k, k) != 0 {
s = 0
for i = k; i < rows; i++ {
s += qr.Get(i, k) * q.Get(i, j)
}
s = -s / qr.Get(k, k)
for i = k; i < rows; i++ {
q.Set(i, j, q.Get(i, j)+s*qr.Get(i, k))
}
}
}
}
return
}
// Transpose flips a matrix about its diagonal, returning a new copy.
func (m *Matrix) Transpose() *Matrix {
rows, cols := m.Size()
m2 := Zero(cols, rows)
for i := 0; i < rows; i++ {
for j := 0; j < cols; j++ {
m2.Set(j, i, m.Get(i, j))
}
}
return m2
}
// Inverse returns a matrix such that M*I==1.
func (m *Matrix) Inverse() (*Matrix, error) {
if !m.IsSymmetric() {
return nil, ErrDimensionMismatch
}
rows, cols := m.Size()
aug, _ := m.Augment(Eye(rows))
for i := 0; i < rows; i++ {
j := i
for k := i; k < rows; k++ {
if math.Abs(aug.Get(k, i)) > math.Abs(aug.Get(j, i)) {
j = k
}
}
if j != i {
aug.SwapRows(i, j)
}
if aug.Get(i, i) == 0 {
return nil, ErrSingularValue
}
aug.ScaleRow(i, 1.0/aug.Get(i, i))
for k := 0; k < rows; k++ {
if k == i {
continue
}
aug.scaleAddRow(k, i, -aug.Get(k, i))
}
}
return aug.SubMatrix(0, cols, rows, cols), nil
}
package matrix
import "errors"
var (
// ErrPolyRegArraysSameLength is a common error.
ErrPolyRegArraysSameLength = errors.New("polynomial array inputs must be the same length")
)
// Poly returns the polynomial regress of a given degree over the given values.
func Poly(xvalues, yvalues []float64, degree int) ([]float64, error) {
if len(xvalues) != len(yvalues) {
return nil, ErrPolyRegArraysSameLength
}
m := len(yvalues)
n := degree + 1
y := New(m, 1, yvalues...)
x := Zero(m, n)
for i := 0; i < m; i++ {
ip := float64(1)
for j := 0; j < n; j++ {
x.Set(i, j, ip)
ip *= xvalues[i]
}
}
q, r := x.QR()
qty, err := q.Transpose().Times(y)
if err != nil {
return nil, err
}
c := make([]float64, n)
for i := n - 1; i >= 0; i-- {
c[i] = qty.Get(i, 0)
for j := i + 1; j < n; j++ {
c[i] -= c[j] * r.Get(i, j)
}
c[i] /= r.Get(i, i)
}
return c, nil
}
package matrix
import (
"math"
"strconv"
)
func minInt(values ...int) int {
min := math.MaxInt32
for x := 0; x < len(values); x++ {
if values[x] < min {
min = values[x]
}
}
return min
}
func maxInt(values ...int) int {
max := math.MinInt32
for x := 0; x < len(values); x++ {
if values[x] > max {
max = values[x]
}
}
return max
}
func f64s(v float64) string {
return strconv.FormatFloat(v, 'f', -1, 64)
}
func roundToEpsilon(value, epsilon float64) float64 {
return math.Nextafter(value, value)
}
package matrix
// Vector is just an array of values.
type Vector []float64
// DotProduct returns the dot product of two vectors.
func (v Vector) DotProduct(v2 Vector) (result float64, err error) {
if len(v) != len(v2) {
err = ErrDimensionMismatch
return
}
for i := 0; i < len(v); i++ {
result = result + (v[i] * v2[i])
}
return
}
package chart
import (
"fmt"
"math"
)
// MinSeries draws a horizontal line at the minimum value of the inner series.
type MinSeries struct {
Name string
Style Style
YAxis YAxisType
InnerSeries ValuesProvider
minValue *float64
}
// GetName returns the name of the time series.
func (ms MinSeries) GetName() string {
return ms.Name
}
// GetStyle returns the line style.
func (ms MinSeries) GetStyle() Style {
return ms.Style
}
// GetYAxis returns which YAxis the series draws on.
func (ms MinSeries) GetYAxis() YAxisType {
return ms.YAxis
}
// Len returns the number of elements in the series.
func (ms MinSeries) Len() int {
return ms.InnerSeries.Len()
}
// GetValues gets a value at a given index.
func (ms *MinSeries) GetValues(index int) (x, y float64) {
ms.ensureMinValue()
x, _ = ms.InnerSeries.GetValues(index)
y = *ms.minValue
return
}
// Render renders the series.
func (ms *MinSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) {
style := ms.Style.InheritFrom(defaults)
Draw.LineSeries(r, canvasBox, xrange, yrange, style, ms)
}
func (ms *MinSeries) ensureMinValue() {
if ms.minValue == nil {
minValue := math.MaxFloat64
var y float64
for x := 0; x < ms.InnerSeries.Len(); x++ {
_, y = ms.InnerSeries.GetValues(x)
if y < minValue {
minValue = y
}
}
ms.minValue = &minValue
}
}
// Validate validates the series.
func (ms *MinSeries) Validate() error {
if ms.InnerSeries == nil {
return fmt.Errorf("min series requires InnerSeries to be set")
}
return nil
}
// MaxSeries draws a horizontal line at the maximum value of the inner series.
type MaxSeries struct {
Name string
Style Style
YAxis YAxisType
InnerSeries ValuesProvider
maxValue *float64
}
// GetName returns the name of the time series.
func (ms MaxSeries) GetName() string {
return ms.Name
}
// GetStyle returns the line style.
func (ms MaxSeries) GetStyle() Style {
return ms.Style
}
// GetYAxis returns which YAxis the series draws on.
func (ms MaxSeries) GetYAxis() YAxisType {
return ms.YAxis
}
// Len returns the number of elements in the series.
func (ms MaxSeries) Len() int {
return ms.InnerSeries.Len()
}
// GetValues gets a value at a given index.
func (ms *MaxSeries) GetValues(index int) (x, y float64) {
ms.ensureMaxValue()
x, _ = ms.InnerSeries.GetValues(index)
y = *ms.maxValue
return
}
// Render renders the series.
func (ms *MaxSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) {
style := ms.Style.InheritFrom(defaults)
Draw.LineSeries(r, canvasBox, xrange, yrange, style, ms)
}
func (ms *MaxSeries) ensureMaxValue() {
if ms.maxValue == nil {
maxValue := -math.MaxFloat64
var y float64
for x := 0; x < ms.InnerSeries.Len(); x++ {
_, y = ms.InnerSeries.GetValues(x)
if y > maxValue {
maxValue = y
}
}
ms.maxValue = &maxValue
}
}
// Validate validates the series.
func (ms *MaxSeries) Validate() error {
if ms.InnerSeries == nil {
return fmt.Errorf("max series requires InnerSeries to be set")
}
return nil
}
package chart
import (
"errors"
"fmt"
"io"
"math"
"github.com/golang/freetype/truetype"
"github.com/wcharczuk/go-chart/util"
)
const (
_pi = math.Pi
_pi2 = math.Pi / 2.0
_pi4 = math.Pi / 4.0
)
// PieChart is a chart that draws sections of a circle based on percentages.
type PieChart struct {
Title string
TitleStyle Style
ColorPalette ColorPalette
Width int
Height int
DPI float64
Background Style
Canvas Style
SliceStyle Style
Font *truetype.Font
defaultFont *truetype.Font
Values []Value
Elements []Renderable
}
// GetDPI returns the dpi for the chart.
func (pc PieChart) GetDPI(defaults ...float64) float64 {
if pc.DPI == 0 {
if len(defaults) > 0 {
return defaults[0]
}
return DefaultDPI
}
return pc.DPI
}
// GetFont returns the text font.
func (pc PieChart) GetFont() *truetype.Font {
if pc.Font == nil {
return pc.defaultFont
}
return pc.Font
}
// GetWidth returns the chart width or the default value.
func (pc PieChart) GetWidth() int {
if pc.Width == 0 {
return DefaultChartWidth
}
return pc.Width
}
// GetHeight returns the chart height or the default value.
func (pc PieChart) GetHeight() int {
if pc.Height == 0 {
return DefaultChartWidth
}
return pc.Height
}
// Render renders the chart with the given renderer to the given io.Writer.
func (pc PieChart) Render(rp RendererProvider, w io.Writer) error {
if len(pc.Values) == 0 {
return errors.New("please provide at least one value")
}
r, err := rp(pc.GetWidth(), pc.GetHeight())
if err != nil {
return err
}
if pc.Font == nil {
defaultFont, err := GetDefaultFont()
if err != nil {
return err
}
pc.defaultFont = defaultFont
}
r.SetDPI(pc.GetDPI(DefaultDPI))
canvasBox := pc.getDefaultCanvasBox()
canvasBox = pc.getCircleAdjustedCanvasBox(canvasBox)
pc.drawBackground(r)
pc.drawCanvas(r, canvasBox)
finalValues, err := pc.finalizeValues(pc.Values)
if err != nil {
return err
}
pc.drawSlices(r, canvasBox, finalValues)
pc.drawTitle(r)
for _, a := range pc.Elements {
a(r, canvasBox, pc.styleDefaultsElements())
}
return r.Save(w)
}
func (pc PieChart) drawBackground(r Renderer) {
Draw.Box(r, Box{
Right: pc.GetWidth(),
Bottom: pc.GetHeight(),
}, pc.getBackgroundStyle())
}
func (pc PieChart) drawCanvas(r Renderer, canvasBox Box) {
Draw.Box(r, canvasBox, pc.getCanvasStyle())
}
func (pc PieChart) drawTitle(r Renderer) {
if len(pc.Title) > 0 && pc.TitleStyle.Show {
Draw.TextWithin(r, pc.Title, pc.Box(), pc.styleDefaultsTitle())
}
}
func (pc PieChart) drawSlices(r Renderer, canvasBox Box, values []Value) {
cx, cy := canvasBox.Center()
diameter := util.Math.MinInt(canvasBox.Width(), canvasBox.Height())
radius := float64(diameter >> 1)
labelRadius := (radius * 2.0) / 3.0
// draw the pie slices
var rads, delta, delta2, total float64
var lx, ly int
if len(values) == 1 {
pc.stylePieChartValue(0).WriteToRenderer(r)
r.MoveTo(cx, cy)
r.Circle(radius, cx, cy)
} else {
for index, v := range values {
v.Style.InheritFrom(pc.stylePieChartValue(index)).WriteToRenderer(r)
r.MoveTo(cx, cy)
rads = util.Math.PercentToRadians(total)
delta = util.Math.PercentToRadians(v.Value)
r.ArcTo(cx, cy, radius, radius, rads, delta)
r.LineTo(cx, cy)
r.Close()
r.FillStroke()
total = total + v.Value
}
}
// draw the labels
total = 0
for index, v := range values {
v.Style.InheritFrom(pc.stylePieChartValue(index)).WriteToRenderer(r)
if len(v.Label) > 0 {
delta2 = util.Math.PercentToRadians(total + (v.Value / 2.0))
delta2 = util.Math.RadianAdd(delta2, _pi2)
lx, ly = util.Math.CirclePoint(cx, cy, labelRadius, delta2)
tb := r.MeasureText(v.Label)
lx = lx - (tb.Width() >> 1)
ly = ly + (tb.Height() >> 1)
if lx < 0 {
lx = 0
}
if ly < 0 {
lx = 0
}
r.Text(v.Label, lx, ly)
}
total = total + v.Value
}
}
func (pc PieChart) finalizeValues(values []Value) ([]Value, error) {
finalValues := Values(values).Normalize()
if len(finalValues) == 0 {
return nil, fmt.Errorf("pie chart must contain at least (1) non-zero value")
}
return finalValues, nil
}
func (pc PieChart) getDefaultCanvasBox() Box {
return pc.Box()
}
func (pc PieChart) getCircleAdjustedCanvasBox(canvasBox Box) Box {
circleDiameter := util.Math.MinInt(canvasBox.Width(), canvasBox.Height())
square := Box{
Right: circleDiameter,
Bottom: circleDiameter,
}
return canvasBox.Fit(square)
}
func (pc PieChart) getBackgroundStyle() Style {
return pc.Background.InheritFrom(pc.styleDefaultsBackground())
}
func (pc PieChart) getCanvasStyle() Style {
return pc.Canvas.InheritFrom(pc.styleDefaultsCanvas())
}
func (pc PieChart) styleDefaultsCanvas() Style {
return Style{
FillColor: pc.GetColorPalette().CanvasColor(),
StrokeColor: pc.GetColorPalette().CanvasStrokeColor(),
StrokeWidth: DefaultStrokeWidth,
}
}
func (pc PieChart) styleDefaultsPieChartValue() Style {
return Style{
StrokeColor: pc.GetColorPalette().TextColor(),
StrokeWidth: 5.0,
FillColor: pc.GetColorPalette().TextColor(),
}
}
func (pc PieChart) stylePieChartValue(index int) Style {
return pc.SliceStyle.InheritFrom(Style{
StrokeColor: ColorWhite,
StrokeWidth: 5.0,
FillColor: pc.GetColorPalette().GetSeriesColor(index),
FontSize: pc.getScaledFontSize(),
FontColor: pc.GetColorPalette().TextColor(),
Font: pc.GetFont(),
})
}
func (pc PieChart) getScaledFontSize() float64 {
effectiveDimension := util.Math.MinInt(pc.GetWidth(), pc.GetHeight())
if effectiveDimension >= 2048 {
return 48.0
} else if effectiveDimension >= 1024 {
return 24.0
} else if effectiveDimension > 512 {
return 18.0
} else if effectiveDimension > 256 {
return 12.0
}
return 10.0
}
func (pc PieChart) styleDefaultsBackground() Style {
return Style{
FillColor: pc.GetColorPalette().BackgroundColor(),
StrokeColor: pc.GetColorPalette().BackgroundStrokeColor(),
StrokeWidth: DefaultStrokeWidth,
}
}
func (pc PieChart) styleDefaultsElements() Style {
return Style{
Font: pc.GetFont(),
}
}
func (pc PieChart) styleDefaultsTitle() Style {
return pc.TitleStyle.InheritFrom(Style{
FontColor: pc.GetColorPalette().TextColor(),
Font: pc.GetFont(),
FontSize: pc.getTitleFontSize(),
TextHorizontalAlign: TextHorizontalAlignCenter,
TextVerticalAlign: TextVerticalAlignTop,
TextWrap: TextWrapWord,
})
}
func (pc PieChart) getTitleFontSize() float64 {
effectiveDimension := util.Math.MinInt(pc.GetWidth(), pc.GetHeight())
if effectiveDimension >= 2048 {
return 48
} else if effectiveDimension >= 1024 {
return 24
} else if effectiveDimension >= 512 {
return 18
} else if effectiveDimension >= 256 {
return 12
}
return 10
}
// GetColorPalette returns the color palette for the chart.
func (pc PieChart) GetColorPalette() ColorPalette {
if pc.ColorPalette != nil {
return pc.ColorPalette
}
return AlternateColorPalette
}
// Box returns the chart bounds as a box.
func (pc PieChart) Box() Box {
dpr := pc.Background.Padding.GetRight(DefaultBackgroundPadding.Right)
dpb := pc.Background.Padding.GetBottom(DefaultBackgroundPadding.Bottom)
return Box{
Top: pc.Background.Padding.GetTop(DefaultBackgroundPadding.Top),
Left: pc.Background.Padding.GetLeft(DefaultBackgroundPadding.Left),
Right: pc.GetWidth() - dpr,
Bottom: pc.GetHeight() - dpb,
}
}
package chart
import (
"fmt"
"math"
"github.com/wcharczuk/go-chart/matrix"
util "github.com/wcharczuk/go-chart/util"
)
// Interface Assertions.
var (
_ Series = (*PolynomialRegressionSeries)(nil)
_ FirstValuesProvider = (*PolynomialRegressionSeries)(nil)
_ LastValuesProvider = (*PolynomialRegressionSeries)(nil)
)
// PolynomialRegressionSeries implements a polynomial regression over a given
// inner series.
type PolynomialRegressionSeries struct {
Name string
Style Style
YAxis YAxisType
Limit int
Offset int
Degree int
InnerSeries ValuesProvider
coeffs []float64
}
// GetName returns the name of the time series.
func (prs PolynomialRegressionSeries) GetName() string {
return prs.Name
}
// GetStyle returns the line style.
func (prs PolynomialRegressionSeries) GetStyle() Style {
return prs.Style
}
// GetYAxis returns which YAxis the series draws on.
func (prs PolynomialRegressionSeries) GetYAxis() YAxisType {
return prs.YAxis
}
// Len returns the number of elements in the series.
func (prs PolynomialRegressionSeries) Len() int {
return util.Math.MinInt(prs.GetLimit(), prs.InnerSeries.Len()-prs.GetOffset())
}
// GetLimit returns the window size.
func (prs PolynomialRegressionSeries) GetLimit() int {
if prs.Limit == 0 {
return prs.InnerSeries.Len()
}
return prs.Limit
}
// GetEndIndex returns the effective limit end.
func (prs PolynomialRegressionSeries) GetEndIndex() int {
windowEnd := prs.GetOffset() + prs.GetLimit()
innerSeriesLastIndex := prs.InnerSeries.Len() - 1
return util.Math.MinInt(windowEnd, innerSeriesLastIndex)
}
// GetOffset returns the data offset.
func (prs PolynomialRegressionSeries) GetOffset() int {
if prs.Offset == 0 {
return 0
}
return prs.Offset
}
// Validate validates the series.
func (prs *PolynomialRegressionSeries) Validate() error {
if prs.InnerSeries == nil {
return fmt.Errorf("linear regression series requires InnerSeries to be set")
}
endIndex := prs.GetEndIndex()
if endIndex >= prs.InnerSeries.Len() {
return fmt.Errorf("invalid window; inner series has length %d but end index is %d", prs.InnerSeries.Len(), endIndex)
}
return nil
}
// GetValues returns the series value for a given index.
func (prs *PolynomialRegressionSeries) GetValues(index int) (x, y float64) {
if prs.InnerSeries == nil || prs.InnerSeries.Len() == 0 {
return
}
if prs.coeffs == nil {
coeffs, err := prs.computeCoefficients()
if err != nil {
panic(err)
}
prs.coeffs = coeffs
}
offset := prs.GetOffset()
effectiveIndex := util.Math.MinInt(index+offset, prs.InnerSeries.Len())
x, y = prs.InnerSeries.GetValues(effectiveIndex)
y = prs.apply(x)
return
}
// GetFirstValues computes the first poly regression value.
func (prs *PolynomialRegressionSeries) GetFirstValues() (x, y float64) {
if prs.InnerSeries == nil || prs.InnerSeries.Len() == 0 {
return
}
if prs.coeffs == nil {
coeffs, err := prs.computeCoefficients()
if err != nil {
panic(err)
}
prs.coeffs = coeffs
}
x, y = prs.InnerSeries.GetValues(0)
y = prs.apply(x)
return
}
// GetLastValues computes the last poly regression value.
func (prs *PolynomialRegressionSeries) GetLastValues() (x, y float64) {
if prs.InnerSeries == nil || prs.InnerSeries.Len() == 0 {
return
}
if prs.coeffs == nil {
coeffs, err := prs.computeCoefficients()
if err != nil {
panic(err)
}
prs.coeffs = coeffs
}
endIndex := prs.GetEndIndex()
x, y = prs.InnerSeries.GetValues(endIndex)
y = prs.apply(x)
return
}
func (prs *PolynomialRegressionSeries) apply(v float64) (out float64) {
for index, coeff := range prs.coeffs {
out = out + (coeff * math.Pow(v, float64(index)))
}
return
}
func (prs *PolynomialRegressionSeries) computeCoefficients() ([]float64, error) {
xvalues, yvalues := prs.values()
return matrix.Poly(xvalues, yvalues, prs.Degree)
}
func (prs *PolynomialRegressionSeries) values() (xvalues, yvalues []float64) {
startIndex := prs.GetOffset()
endIndex := prs.GetEndIndex()
xvalues = make([]float64, endIndex-startIndex)
yvalues = make([]float64, endIndex-startIndex)
for index := startIndex; index < endIndex; index++ {
x, y := prs.InnerSeries.GetValues(index)
xvalues[index-startIndex] = x
yvalues[index-startIndex] = y
}
return
}
// Render renders the series.
func (prs *PolynomialRegressionSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) {
style := prs.Style.InheritFrom(defaults)
Draw.LineSeries(r, canvasBox, xrange, yrange, style, prs)
}
package chart
import (
"image"
"image/png"
"io"
"math"
"github.com/golang/freetype/truetype"
"github.com/wcharczuk/go-chart/drawing"
"github.com/wcharczuk/go-chart/util"
)
// PNG returns a new png/raster renderer.
func PNG(width, height int) (Renderer, error) {
i := image.NewRGBA(image.Rect(0, 0, width, height))
gc, err := drawing.NewRasterGraphicContext(i)
if err == nil {
return &rasterRenderer{
i: i,
gc: gc,
}, nil
}
return nil, err
}
// rasterRenderer renders chart commands to a bitmap.
type rasterRenderer struct {
i *image.RGBA
gc *drawing.RasterGraphicContext
rotateRadians *float64
s Style
}
func (rr *rasterRenderer) ResetStyle() {
rr.s = Style{Font: rr.s.Font}
rr.ClearTextRotation()
}
// GetDPI returns the dpi.
func (rr *rasterRenderer) GetDPI() float64 {
return rr.gc.GetDPI()
}
// SetDPI implements the interface method.
func (rr *rasterRenderer) SetDPI(dpi float64) {
rr.gc.SetDPI(dpi)
}
// SetClassName implements the interface method. However, PNGs have no classes.
func (vr *rasterRenderer) SetClassName(_ string) {
}
// SetStrokeColor implements the interface method.
func (rr *rasterRenderer) SetStrokeColor(c drawing.Color) {
rr.s.StrokeColor = c
}
// SetLineWidth implements the interface method.
func (rr *rasterRenderer) SetStrokeWidth(width float64) {
rr.s.StrokeWidth = width
}
// StrokeDashArray sets the stroke dash array.
func (rr *rasterRenderer) SetStrokeDashArray(dashArray []float64) {
rr.s.StrokeDashArray = dashArray
}
// SetFillColor implements the interface method.
func (rr *rasterRenderer) SetFillColor(c drawing.Color) {
rr.s.FillColor = c
}
// MoveTo implements the interface method.
func (rr *rasterRenderer) MoveTo(x, y int) {
rr.gc.MoveTo(float64(x), float64(y))
}
// LineTo implements the interface method.
func (rr *rasterRenderer) LineTo(x, y int) {
rr.gc.LineTo(float64(x), float64(y))
}
// QuadCurveTo implements the interface method.
func (rr *rasterRenderer) QuadCurveTo(cx, cy, x, y int) {
rr.gc.QuadCurveTo(float64(cx), float64(cy), float64(x), float64(y))
}
// ArcTo implements the interface method.
func (rr *rasterRenderer) ArcTo(cx, cy int, rx, ry, startAngle, delta float64) {
rr.gc.ArcTo(float64(cx), float64(cy), rx, ry, startAngle, delta)
}
// Close implements the interface method.
func (rr *rasterRenderer) Close() {
rr.gc.Close()
}
// Stroke implements the interface method.
func (rr *rasterRenderer) Stroke() {
rr.gc.SetStrokeColor(rr.s.StrokeColor)
rr.gc.SetLineWidth(rr.s.StrokeWidth)
rr.gc.SetLineDash(rr.s.StrokeDashArray, 0)
rr.gc.Stroke()
}
// Fill implements the interface method.
func (rr *rasterRenderer) Fill() {
rr.gc.SetFillColor(rr.s.FillColor)
rr.gc.Fill()
}
// FillStroke implements the interface method.
func (rr *rasterRenderer) FillStroke() {
rr.gc.SetFillColor(rr.s.FillColor)
rr.gc.SetStrokeColor(rr.s.StrokeColor)
rr.gc.SetLineWidth(rr.s.StrokeWidth)
rr.gc.SetLineDash(rr.s.StrokeDashArray, 0)
rr.gc.FillStroke()
}
// Circle fully draws a circle at a given point but does not apply the fill or stroke.
func (rr *rasterRenderer) Circle(radius float64, x, y int) {
xf := float64(x)
yf := float64(y)
rr.gc.MoveTo(xf-radius, yf) //9
rr.gc.QuadCurveTo(xf-radius, yf-radius, xf, yf-radius) //12
rr.gc.QuadCurveTo(xf+radius, yf-radius, xf+radius, yf) //3
rr.gc.QuadCurveTo(xf+radius, yf+radius, xf, yf+radius) //6
rr.gc.QuadCurveTo(xf-radius, yf+radius, xf-radius, yf) //9
}
// SetFont implements the interface method.
func (rr *rasterRenderer) SetFont(f *truetype.Font) {
rr.s.Font = f
}
// SetFontSize implements the interface method.
func (rr *rasterRenderer) SetFontSize(size float64) {
rr.s.FontSize = size
}
// SetFontColor implements the interface method.
func (rr *rasterRenderer) SetFontColor(c drawing.Color) {
rr.s.FontColor = c
}
// Text implements the interface method.
func (rr *rasterRenderer) Text(body string, x, y int) {
xf, yf := rr.getCoords(x, y)
rr.gc.SetFont(rr.s.Font)
rr.gc.SetFontSize(rr.s.FontSize)
rr.gc.SetFillColor(rr.s.FontColor)
rr.gc.CreateStringPath(body, float64(xf), float64(yf))
rr.gc.Fill()
}
// MeasureText returns the height and width in pixels of a string.
func (rr *rasterRenderer) MeasureText(body string) Box {
rr.gc.SetFont(rr.s.Font)
rr.gc.SetFontSize(rr.s.FontSize)
rr.gc.SetFillColor(rr.s.FontColor)
l, t, r, b, err := rr.gc.GetStringBounds(body)
if err != nil {
return Box{}
}
if l < 0 {
r = r - l // equivalent to r+(-1*l)
l = 0
}
if t < 0 {
b = b - t
t = 0
}
if l > 0 {
r = r + l
l = 0
}
if t > 0 {
b = b + t
t = 0
}
textBox := Box{
Top: int(math.Ceil(t)),
Left: int(math.Ceil(l)),
Right: int(math.Ceil(r)),
Bottom: int(math.Ceil(b)),
}
if rr.rotateRadians == nil {
return textBox
}
return textBox.Corners().Rotate(util.Math.RadiansToDegrees(*rr.rotateRadians)).Box()
}
// SetTextRotation sets a text rotation.
func (rr *rasterRenderer) SetTextRotation(radians float64) {
rr.rotateRadians = &radians
}
func (rr *rasterRenderer) getCoords(x, y int) (xf, yf int) {
if rr.rotateRadians == nil {
xf = x
yf = y
return
}
rr.gc.Translate(float64(x), float64(y))
rr.gc.Rotate(*rr.rotateRadians)
return
}
// ClearTextRotation clears text rotation.
func (rr *rasterRenderer) ClearTextRotation() {
rr.gc.SetMatrixTransform(drawing.NewIdentityMatrix())
rr.rotateRadians = nil
}
// Save implements the interface method.
func (rr *rasterRenderer) Save(w io.Writer) error {
if typed, isTyped := w.(RGBACollector); isTyped {
typed.SetRGBA(rr.i)
return nil
}
return png.Encode(w, rr.i)
}
package seq
// NewArray creates a new array.
func NewArray(values ...float64) Array {
return Array(values)
}
// Array is a wrapper for an array of floats that implements `ValuesProvider`.
type Array []float64
// Len returns the value provider length.
func (a Array) Len() int {
return len(a)
}
// GetValue returns the value at a given index.
func (a Array) GetValue(index int) float64 {
return a[index]
}
package seq
import (
"fmt"
"strings"
util "github.com/wcharczuk/go-chart/util"
)
const (
bufferMinimumGrow = 4
bufferShrinkThreshold = 32
bufferGrowFactor = 200
bufferDefaultCapacity = 4
)
var (
emptyArray = make([]float64, 0)
)
// NewBuffer creates a new value buffer with an optional set of values.
func NewBuffer(values ...float64) *Buffer {
var tail int
array := make([]float64, util.Math.MaxInt(len(values), bufferDefaultCapacity))
if len(values) > 0 {
copy(array, values)
tail = len(values)
}
return &Buffer{
array: array,
head: 0,
tail: tail,
size: len(values),
}
}
// NewBufferWithCapacity creates a new ValueBuffer pre-allocated with the given capacity.
func NewBufferWithCapacity(capacity int) *Buffer {
return &Buffer{
array: make([]float64, capacity),
head: 0,
tail: 0,
size: 0,
}
}
// Buffer is a fifo datastructure that is backed by a pre-allocated array.
// Instead of allocating a whole new node object for each element, array elements are re-used (which saves GC churn).
// Enqueue can be O(n), Dequeue is generally O(1).
// Buffer implements `seq.Provider`
type Buffer struct {
array []float64
head int
tail int
size int
}
// Len returns the length of the Buffer (as it is currently populated).
// Actual memory footprint may be different.
func (b *Buffer) Len() int {
return b.size
}
// GetValue implements seq provider.
func (b *Buffer) GetValue(index int) float64 {
effectiveIndex := (b.head + index) % len(b.array)
return b.array[effectiveIndex]
}
// Capacity returns the total size of the Buffer, including empty elements.
func (b *Buffer) Capacity() int {
return len(b.array)
}
// SetCapacity sets the capacity of the Buffer.
func (b *Buffer) SetCapacity(capacity int) {
newArray := make([]float64, capacity)
if b.size > 0 {
if b.head < b.tail {
arrayCopy(b.array, b.head, newArray, 0, b.size)
} else {
arrayCopy(b.array, b.head, newArray, 0, len(b.array)-b.head)
arrayCopy(b.array, 0, newArray, len(b.array)-b.head, b.tail)
}
}
b.array = newArray
b.head = 0
if b.size == capacity {
b.tail = 0
} else {
b.tail = b.size
}
}
// Clear removes all objects from the Buffer.
func (b *Buffer) Clear() {
b.array = make([]float64, bufferDefaultCapacity)
b.head = 0
b.tail = 0
b.size = 0
}
// Enqueue adds an element to the "back" of the Buffer.
func (b *Buffer) Enqueue(value float64) {
if b.size == len(b.array) {
newCapacity := int(len(b.array) * int(bufferGrowFactor/100))
if newCapacity < (len(b.array) + bufferMinimumGrow) {
newCapacity = len(b.array) + bufferMinimumGrow
}
b.SetCapacity(newCapacity)
}
b.array[b.tail] = value
b.tail = (b.tail + 1) % len(b.array)
b.size++
}
// Dequeue removes the first element from the RingBuffer.
func (b *Buffer) Dequeue() float64 {
if b.size == 0 {
return 0
}
removed := b.array[b.head]
b.head = (b.head + 1) % len(b.array)
b.size--
return removed
}
// Peek returns but does not remove the first element.
func (b *Buffer) Peek() float64 {
if b.size == 0 {
return 0
}
return b.array[b.head]
}
// PeekBack returns but does not remove the last element.
func (b *Buffer) PeekBack() float64 {
if b.size == 0 {
return 0
}
if b.tail == 0 {
return b.array[len(b.array)-1]
}
return b.array[b.tail-1]
}
// TrimExcess resizes the capacity of the buffer to better fit the contents.
func (b *Buffer) TrimExcess() {
threshold := float64(len(b.array)) * 0.9
if b.size < int(threshold) {
b.SetCapacity(b.size)
}
}
// Array returns the ring buffer, in order, as an array.
func (b *Buffer) Array() Array {
newArray := make([]float64, b.size)
if b.size == 0 {
return newArray
}
if b.head < b.tail {
arrayCopy(b.array, b.head, newArray, 0, b.size)
} else {
arrayCopy(b.array, b.head, newArray, 0, len(b.array)-b.head)
arrayCopy(b.array, 0, newArray, len(b.array)-b.head, b.tail)
}
return Array(newArray)
}
// Each calls the consumer for each element in the buffer.
func (b *Buffer) Each(mapfn func(int, float64)) {
if b.size == 0 {
return
}
var index int
if b.head < b.tail {
for cursor := b.head; cursor < b.tail; cursor++ {
mapfn(index, b.array[cursor])
index++
}
} else {
for cursor := b.head; cursor < len(b.array); cursor++ {
mapfn(index, b.array[cursor])
index++
}
for cursor := 0; cursor < b.tail; cursor++ {
mapfn(index, b.array[cursor])
index++
}
}
}
// String returns a string representation for value buffers.
func (b *Buffer) String() string {
var values []string
for _, elem := range b.Array() {
values = append(values, fmt.Sprintf("%v", elem))
}
return strings.Join(values, " <= ")
}
// --------------------------------------------------------------------------------
// Util methods
// --------------------------------------------------------------------------------
func arrayClear(source []float64, index, length int) {
for x := 0; x < length; x++ {
absoluteIndex := x + index
source[absoluteIndex] = 0
}
}
func arrayCopy(source []float64, sourceIndex int, destination []float64, destinationIndex, length int) {
for x := 0; x < length; x++ {
from := sourceIndex + x
to := destinationIndex + x
destination[to] = source[from]
}
}
package seq
// Range returns the array values of a linear seq with a given start, end and optional step.
func Range(start, end float64) []float64 {
return Seq{NewLinear().WithStart(start).WithEnd(end).WithStep(1.0)}.Array()
}
// RangeWithStep returns the array values of a linear seq with a given start, end and optional step.
func RangeWithStep(start, end, step float64) []float64 {
return Seq{NewLinear().WithStart(start).WithEnd(end).WithStep(step)}.Array()
}
// NewLinear returns a new linear generator.
func NewLinear() *Linear {
return &Linear{step: 1.0}
}
// Linear is a stepwise generator.
type Linear struct {
start float64
end float64
step float64
}
// Start returns the start value.
func (lg Linear) Start() float64 {
return lg.start
}
// End returns the end value.
func (lg Linear) End() float64 {
return lg.end
}
// Step returns the step value.
func (lg Linear) Step() float64 {
return lg.step
}
// Len returns the number of elements in the seq.
func (lg Linear) Len() int {
if lg.start < lg.end {
return int((lg.end-lg.start)/lg.step) + 1
}
return int((lg.start-lg.end)/lg.step) + 1
}
// GetValue returns the value at a given index.
func (lg Linear) GetValue(index int) float64 {
fi := float64(index)
if lg.start < lg.end {
return lg.start + (fi * lg.step)
}
return lg.start - (fi * lg.step)
}
// WithStart sets the start and returns the linear generator.
func (lg *Linear) WithStart(start float64) *Linear {
lg.start = start
return lg
}
// WithEnd sets the end and returns the linear generator.
func (lg *Linear) WithEnd(end float64) *Linear {
lg.end = end
return lg
}
// WithStep sets the step and returns the linear generator.
func (lg *Linear) WithStep(step float64) *Linear {
lg.step = step
return lg
}
package seq
import (
"math"
"math/rand"
"time"
)
// RandomValues returns an array of random values.
func RandomValues(count int) []float64 {
return Seq{NewRandom().WithLen(count)}.Array()
}
// RandomValuesWithMax returns an array of random values with a given average.
func RandomValuesWithMax(count int, max float64) []float64 {
return Seq{NewRandom().WithMax(max).WithLen(count)}.Array()
}
// NewRandom creates a new random seq.
func NewRandom() *Random {
return &Random{
rnd: rand.New(rand.NewSource(time.Now().Unix())),
}
}
// Random is a random number seq generator.
type Random struct {
rnd *rand.Rand
max *float64
min *float64
len *int
}
// Len returns the number of elements that will be generated.
func (r *Random) Len() int {
if r.len != nil {
return *r.len
}
return math.MaxInt32
}
// GetValue returns the value.
func (r *Random) GetValue(_ int) float64 {
if r.min != nil && r.max != nil {
var delta float64
if *r.max > *r.min {
delta = *r.max - *r.min
} else {
delta = *r.min - *r.max
}
return *r.min + (r.rnd.Float64() * delta)
} else if r.max != nil {
return r.rnd.Float64() * *r.max
} else if r.min != nil {
return *r.min + (r.rnd.Float64())
}
return r.rnd.Float64()
}
// WithLen sets a maximum len
func (r *Random) WithLen(length int) *Random {
r.len = &length
return r
}
// Min returns the minimum value.
func (r Random) Min() *float64 {
return r.min
}
// WithMin sets the scale and returns the Random.
func (r *Random) WithMin(min float64) *Random {
r.min = &min
return r
}
// Max returns the maximum value.
func (r Random) Max() *float64 {
return r.max
}
// WithMax sets the average and returns the Random.
func (r *Random) WithMax(max float64) *Random {
r.max = &max
return r
}
package seq
import (
"math"
"sort"
)
// New wraps a provider with a seq.
func New(provider Provider) Seq {
return Seq{Provider: provider}
}
// Values returns a new seq composed of a given set of values.
func Values(values ...float64) Seq {
return Seq{Provider: Array(values)}
}
// Provider is a provider for values for a seq.
type Provider interface {
Len() int
GetValue(int) float64
}
// Seq is a utility wrapper for seq providers.
type Seq struct {
Provider
}
// Array enumerates the seq into a slice.
func (s Seq) Array() (output []float64) {
if s.Len() == 0 {
return
}
output = make([]float64, s.Len())
for i := 0; i < s.Len(); i++ {
output[i] = s.GetValue(i)
}
return
}
// Each applies the `mapfn` to all values in the value provider.
func (s Seq) Each(mapfn func(int, float64)) {
for i := 0; i < s.Len(); i++ {
mapfn(i, s.GetValue(i))
}
}
// Map applies the `mapfn` to all values in the value provider,
// returning a new seq.
func (s Seq) Map(mapfn func(i int, v float64) float64) Seq {
output := make([]float64, s.Len())
for i := 0; i < s.Len(); i++ {
mapfn(i, s.GetValue(i))
}
return Seq{Array(output)}
}
// FoldLeft collapses a seq from left to right.
func (s Seq) FoldLeft(mapfn func(i int, v0, v float64) float64) (v0 float64) {
if s.Len() == 0 {
return 0
}
if s.Len() == 1 {
return s.GetValue(0)
}
v0 = s.GetValue(0)
for i := 1; i < s.Len(); i++ {
v0 = mapfn(i, v0, s.GetValue(i))
}
return
}
// FoldRight collapses a seq from right to left.
func (s Seq) FoldRight(mapfn func(i int, v0, v float64) float64) (v0 float64) {
if s.Len() == 0 {
return 0
}
if s.Len() == 1 {
return s.GetValue(0)
}
v0 = s.GetValue(s.Len() - 1)
for i := s.Len() - 2; i >= 0; i-- {
v0 = mapfn(i, v0, s.GetValue(i))
}
return
}
// Min returns the minimum value in the seq.
func (s Seq) Min() float64 {
if s.Len() == 0 {
return 0
}
min := s.GetValue(0)
var value float64
for i := 1; i < s.Len(); i++ {
value = s.GetValue(i)
if value < min {
min = value
}
}
return min
}
// Max returns the maximum value in the seq.
func (s Seq) Max() float64 {
if s.Len() == 0 {
return 0
}
max := s.GetValue(0)
var value float64
for i := 1; i < s.Len(); i++ {
value = s.GetValue(i)
if value > max {
max = value
}
}
return max
}
// MinMax returns the minimum and the maximum in one pass.
func (s Seq) MinMax() (min, max float64) {
if s.Len() == 0 {
return
}
min = s.GetValue(0)
max = min
var value float64
for i := 1; i < s.Len(); i++ {
value = s.GetValue(i)
if value < min {
min = value
}
if value > max {
max = value
}
}
return
}
// Sort returns the seq sorted in ascending order.
// This fully enumerates the seq.
func (s Seq) Sort() Seq {
if s.Len() == 0 {
return s
}
values := s.Array()
sort.Float64s(values)
return Seq{Provider: Array(values)}
}
// Median returns the median or middle value in the sorted seq.
func (s Seq) Median() (median float64) {
l := s.Len()
if l == 0 {
return
}
sorted := s.Sort()
if l%2 == 0 {
v0 := sorted.GetValue(l/2 - 1)
v1 := sorted.GetValue(l/2 + 1)
median = (v0 + v1) / 2
} else {
median = float64(sorted.GetValue(l << 1))
}
return
}
// Sum adds all the elements of a series together.
func (s Seq) Sum() (accum float64) {
if s.Len() == 0 {
return 0
}
for i := 0; i < s.Len(); i++ {
accum += s.GetValue(i)
}
return
}
// Average returns the float average of the values in the buffer.
func (s Seq) Average() float64 {
if s.Len() == 0 {
return 0
}
return s.Sum() / float64(s.Len())
}
// Variance computes the variance of the buffer.
func (s Seq) Variance() float64 {
if s.Len() == 0 {
return 0
}
m := s.Average()
var variance, v float64
for i := 0; i < s.Len(); i++ {
v = s.GetValue(i)
variance += (v - m) * (v - m)
}
return variance / float64(s.Len())
}
// StdDev returns the standard deviation.
func (s Seq) StdDev() float64 {
if s.Len() == 0 {
return 0
}
return math.Pow(s.Variance(), 0.5)
}
//Percentile finds the relative standing in a slice of floats.
// `percent` should be given on the interval [0,1.0).
func (s Seq) Percentile(percent float64) (percentile float64) {
l := s.Len()
if l == 0 {
return 0
}
if percent < 0 || percent > 1.0 {
panic("percent out of range [0.0, 1.0)")
}
sorted := s.Sort()
index := percent * float64(l)
if index == float64(int64(index)) {
i := f64i(index)
ci := sorted.GetValue(i - 1)
c := sorted.GetValue(i)
percentile = (ci + c) / 2.0
} else {
i := f64i(index)
percentile = sorted.GetValue(i)
}
return percentile
}
// Normalize maps every value to the interval [0, 1.0].
func (s Seq) Normalize() Seq {
min, max := s.MinMax()
delta := max - min
output := make([]float64, s.Len())
for i := 0; i < s.Len(); i++ {
output[i] = (s.GetValue(i) - min) / delta
}
return Seq{Provider: Array(output)}
}
package seq
import (
"time"
"github.com/wcharczuk/go-chart/util"
)
// Time is a utility singleton with helper functions for time seq generation.
var Time timeSequence
type timeSequence struct{}
// Days generates a seq of timestamps by day, from -days to today.
func (ts timeSequence) Days(days int) []time.Time {
var values []time.Time
for day := days; day >= 0; day-- {
values = append(values, time.Now().AddDate(0, 0, -day))
}
return values
}
func (ts timeSequence) Hours(start time.Time, totalHours int) []time.Time {
times := make([]time.Time, totalHours)
last := start
for i := 0; i < totalHours; i++ {
times[i] = last
last = last.Add(time.Hour)
}
return times
}
// HoursFilled adds zero values for the data bounded by the start and end of the xdata array.
func (ts timeSequence) HoursFilled(xdata []time.Time, ydata []float64) ([]time.Time, []float64) {
start, end := util.Time.StartAndEnd(xdata...)
totalHours := util.Time.DiffHours(start, end)
finalTimes := ts.Hours(start, totalHours+1)
finalValues := make([]float64, totalHours+1)
var hoursFromStart int
for i, xd := range xdata {
hoursFromStart = util.Time.DiffHours(start, xd)
finalValues[hoursFromStart] = ydata[i]
}
return finalTimes, finalValues
}
package seq
import (
"time"
"github.com/wcharczuk/go-chart/util"
)
// Assert types implement interfaces.
var (
_ Provider = (*Times)(nil)
)
// Times are an array of times.
// It wraps the array with methods that implement `seq.Provider`.
type Times []time.Time
// Array returns the times to an array.
func (t Times) Array() []time.Time {
return []time.Time(t)
}
// Len returns the length of the array.
func (t Times) Len() int {
return len(t)
}
// GetValue returns a value at an index as a time.
func (t Times) GetValue(index int) float64 {
return util.Time.ToFloat64(t[index])
}
package seq
import "math"
func round(input float64, places int) (rounded float64) {
if math.IsNaN(input) {
return 0.0
}
sign := 1.0
if input < 0 {
sign = -1
input *= -1
}
precision := math.Pow(10, float64(places))
digit := input * precision
_, decimal := math.Modf(digit)
if decimal >= 0.5 {
rounded = math.Ceil(digit)
} else {
rounded = math.Floor(digit)
}
return rounded / precision * sign
}
func f64i(value float64) int {
r := round(value, 0)
return int(r)
}
package chart
import (
"fmt"
util "github.com/wcharczuk/go-chart/util"
)
const (
// DefaultSimpleMovingAveragePeriod is the default number of values to average.
DefaultSimpleMovingAveragePeriod = 16
)
// Interface Assertions.
var (
_ Series = (*SMASeries)(nil)
_ FirstValuesProvider = (*SMASeries)(nil)
_ LastValuesProvider = (*SMASeries)(nil)
)
// SMASeries is a computed series.
type SMASeries struct {
Name string
Style Style
YAxis YAxisType
Period int
InnerSeries ValuesProvider
}
// GetName returns the name of the time series.
func (sma SMASeries) GetName() string {
return sma.Name
}
// GetStyle returns the line style.
func (sma SMASeries) GetStyle() Style {
return sma.Style
}
// GetYAxis returns which YAxis the series draws on.
func (sma SMASeries) GetYAxis() YAxisType {
return sma.YAxis
}
// Len returns the number of elements in the series.
func (sma SMASeries) Len() int {
return sma.InnerSeries.Len()
}
// GetPeriod returns the window size.
func (sma SMASeries) GetPeriod(defaults ...int) int {
if sma.Period == 0 {
if len(defaults) > 0 {
return defaults[0]
}
return DefaultSimpleMovingAveragePeriod
}
return sma.Period
}
// GetValues gets a value at a given index.
func (sma SMASeries) GetValues(index int) (x, y float64) {
if sma.InnerSeries == nil || sma.InnerSeries.Len() == 0 {
return
}
px, _ := sma.InnerSeries.GetValues(index)
x = px
y = sma.getAverage(index)
return
}
// GetFirstValues computes the first moving average value.
func (sma SMASeries) GetFirstValues() (x, y float64) {
if sma.InnerSeries == nil || sma.InnerSeries.Len() == 0 {
return
}
px, _ := sma.InnerSeries.GetValues(0)
x = px
y = sma.getAverage(0)
return
}
// GetLastValues computes the last moving average value but walking back window size samples,
// and recomputing the last moving average chunk.
func (sma SMASeries) GetLastValues() (x, y float64) {
if sma.InnerSeries == nil || sma.InnerSeries.Len() == 0 {
return
}
seriesLen := sma.InnerSeries.Len()
px, _ := sma.InnerSeries.GetValues(seriesLen - 1)
x = px
y = sma.getAverage(seriesLen - 1)
return
}
func (sma SMASeries) getAverage(index int) float64 {
period := sma.GetPeriod()
floor := util.Math.MaxInt(0, index-period)
var accum float64
var count float64
for x := index; x >= floor; x-- {
_, vy := sma.InnerSeries.GetValues(x)
accum += vy
count += 1.0
}
return accum / count
}
// Render renders the series.
func (sma SMASeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) {
style := sma.Style.InheritFrom(defaults)
Draw.LineSeries(r, canvasBox, xrange, yrange, style, sma)
}
// Validate validates the series.
func (sma SMASeries) Validate() error {
if sma.InnerSeries == nil {
return fmt.Errorf("sma series requires InnerSeries to be set")
}
return nil
}
package chart
import (
"errors"
"fmt"
"io"
"math"
"github.com/golang/freetype/truetype"
"github.com/wcharczuk/go-chart/seq"
util "github.com/wcharczuk/go-chart/util"
)
// StackedBar is a bar within a StackedBarChart.
type StackedBar struct {
Name string
Width int
Values []Value
}
// GetWidth returns the width of the bar.
func (sb StackedBar) GetWidth() int {
if sb.Width == 0 {
return 50
}
return sb.Width
}
// StackedBarChart is a chart that draws sections of a bar based on percentages.
type StackedBarChart struct {
Title string
TitleStyle Style
ColorPalette ColorPalette
Width int
Height int
DPI float64
Background Style
Canvas Style
XAxis Style
YAxis Style
BarSpacing int
Font *truetype.Font
defaultFont *truetype.Font
Bars []StackedBar
Elements []Renderable
}
// GetDPI returns the dpi for the chart.
func (sbc StackedBarChart) GetDPI(defaults ...float64) float64 {
if sbc.DPI == 0 {
if len(defaults) > 0 {
return defaults[0]
}
return DefaultDPI
}
return sbc.DPI
}
// GetFont returns the text font.
func (sbc StackedBarChart) GetFont() *truetype.Font {
if sbc.Font == nil {
return sbc.defaultFont
}
return sbc.Font
}
// GetWidth returns the chart width or the default value.
func (sbc StackedBarChart) GetWidth() int {
if sbc.Width == 0 {
return DefaultChartWidth
}
return sbc.Width
}
// GetHeight returns the chart height or the default value.
func (sbc StackedBarChart) GetHeight() int {
if sbc.Height == 0 {
return DefaultChartWidth
}
return sbc.Height
}
// GetBarSpacing returns the spacing between bars.
func (sbc StackedBarChart) GetBarSpacing() int {
if sbc.BarSpacing == 0 {
return 100
}
return sbc.BarSpacing
}
// Render renders the chart with the given renderer to the given io.Writer.
func (sbc StackedBarChart) Render(rp RendererProvider, w io.Writer) error {
if len(sbc.Bars) == 0 {
return errors.New("please provide at least one bar")
}
r, err := rp(sbc.GetWidth(), sbc.GetHeight())
if err != nil {
return err
}
if sbc.Font == nil {
defaultFont, err := GetDefaultFont()
if err != nil {
return err
}
sbc.defaultFont = defaultFont
}
r.SetDPI(sbc.GetDPI(DefaultDPI))
canvasBox := sbc.getAdjustedCanvasBox(r, sbc.getDefaultCanvasBox())
sbc.drawCanvas(r, canvasBox)
sbc.drawBars(r, canvasBox)
sbc.drawXAxis(r, canvasBox)
sbc.drawYAxis(r, canvasBox)
sbc.drawTitle(r)
for _, a := range sbc.Elements {
a(r, canvasBox, sbc.styleDefaultsElements())
}
return r.Save(w)
}
func (sbc StackedBarChart) drawCanvas(r Renderer, canvasBox Box) {
Draw.Box(r, canvasBox, sbc.getCanvasStyle())
}
func (sbc StackedBarChart) drawBars(r Renderer, canvasBox Box) {
xoffset := canvasBox.Left
for _, bar := range sbc.Bars {
sbc.drawBar(r, canvasBox, xoffset, bar)
xoffset += (sbc.GetBarSpacing() + bar.GetWidth())
}
}
func (sbc StackedBarChart) drawBar(r Renderer, canvasBox Box, xoffset int, bar StackedBar) int {
barSpacing2 := sbc.GetBarSpacing() >> 1
bxl := xoffset + barSpacing2
bxr := bxl + bar.GetWidth()
normalizedBarComponents := Values(bar.Values).Normalize()
yoffset := canvasBox.Top
for index, bv := range normalizedBarComponents {
barHeight := int(math.Ceil(bv.Value * float64(canvasBox.Height())))
barBox := Box{
Top: yoffset,
Left: bxl,
Right: bxr,
Bottom: util.Math.MinInt(yoffset+barHeight, canvasBox.Bottom-DefaultStrokeWidth),
}
Draw.Box(r, barBox, bv.Style.InheritFrom(sbc.styleDefaultsStackedBarValue(index)))
yoffset += barHeight
}
return bxr
}
func (sbc StackedBarChart) drawXAxis(r Renderer, canvasBox Box) {
if sbc.XAxis.Show {
axisStyle := sbc.XAxis.InheritFrom(sbc.styleDefaultsAxes())
axisStyle.WriteToRenderer(r)
r.MoveTo(canvasBox.Left, canvasBox.Bottom)
r.LineTo(canvasBox.Right, canvasBox.Bottom)
r.Stroke()
r.MoveTo(canvasBox.Left, canvasBox.Bottom)
r.LineTo(canvasBox.Left, canvasBox.Bottom+DefaultVerticalTickHeight)
r.Stroke()
cursor := canvasBox.Left
for _, bar := range sbc.Bars {
barLabelBox := Box{
Top: canvasBox.Bottom + DefaultXAxisMargin,
Left: cursor,
Right: cursor + bar.GetWidth() + sbc.GetBarSpacing(),
Bottom: sbc.GetHeight(),
}
if len(bar.Name) > 0 {
Draw.TextWithin(r, bar.Name, barLabelBox, axisStyle)
}
axisStyle.WriteToRenderer(r)
r.MoveTo(barLabelBox.Right, canvasBox.Bottom)
r.LineTo(barLabelBox.Right, canvasBox.Bottom+DefaultVerticalTickHeight)
r.Stroke()
cursor += bar.GetWidth() + sbc.GetBarSpacing()
}
}
}
func (sbc StackedBarChart) drawYAxis(r Renderer, canvasBox Box) {
if sbc.YAxis.Show {
axisStyle := sbc.YAxis.InheritFrom(sbc.styleDefaultsAxes())
axisStyle.WriteToRenderer(r)
r.MoveTo(canvasBox.Right, canvasBox.Top)
r.LineTo(canvasBox.Right, canvasBox.Bottom)
r.Stroke()
r.MoveTo(canvasBox.Right, canvasBox.Bottom)
r.LineTo(canvasBox.Right+DefaultHorizontalTickWidth, canvasBox.Bottom)
r.Stroke()
ticks := seq.RangeWithStep(0.0, 1.0, 0.2)
for _, t := range ticks {
axisStyle.GetStrokeOptions().WriteToRenderer(r)
ty := canvasBox.Bottom - int(t*float64(canvasBox.Height()))
r.MoveTo(canvasBox.Right, ty)
r.LineTo(canvasBox.Right+DefaultHorizontalTickWidth, ty)
r.Stroke()
axisStyle.GetTextOptions().WriteToRenderer(r)
text := fmt.Sprintf("%0.0f%%", t*100)
tb := r.MeasureText(text)
Draw.Text(r, text, canvasBox.Right+DefaultYAxisMargin+5, ty+(tb.Height()>>1), axisStyle)
}
}
}
func (sbc StackedBarChart) drawTitle(r Renderer) {
if len(sbc.Title) > 0 && sbc.TitleStyle.Show {
r.SetFont(sbc.TitleStyle.GetFont(sbc.GetFont()))
r.SetFontColor(sbc.TitleStyle.GetFontColor(sbc.GetColorPalette().TextColor()))
titleFontSize := sbc.TitleStyle.GetFontSize(DefaultTitleFontSize)
r.SetFontSize(titleFontSize)
textBox := r.MeasureText(sbc.Title)
textWidth := textBox.Width()
textHeight := textBox.Height()
titleX := (sbc.GetWidth() >> 1) - (textWidth >> 1)
titleY := sbc.TitleStyle.Padding.GetTop(DefaultTitleTop) + textHeight
r.Text(sbc.Title, titleX, titleY)
}
}
func (sbc StackedBarChart) getCanvasStyle() Style {
return sbc.Canvas.InheritFrom(sbc.styleDefaultsCanvas())
}
func (sbc StackedBarChart) styleDefaultsCanvas() Style {
return Style{
FillColor: sbc.GetColorPalette().CanvasColor(),
StrokeColor: sbc.GetColorPalette().CanvasStrokeColor(),
StrokeWidth: DefaultCanvasStrokeWidth,
}
}
// GetColorPalette returns the color palette for the chart.
func (sbc StackedBarChart) GetColorPalette() ColorPalette {
if sbc.ColorPalette != nil {
return sbc.ColorPalette
}
return AlternateColorPalette
}
func (sbc StackedBarChart) getDefaultCanvasBox() Box {
return sbc.Box()
}
func (sbc StackedBarChart) getAdjustedCanvasBox(r Renderer, canvasBox Box) Box {
var totalWidth int
for _, bar := range sbc.Bars {
totalWidth += bar.GetWidth() + sbc.GetBarSpacing()
}
if sbc.XAxis.Show {
xaxisHeight := DefaultVerticalTickHeight
axisStyle := sbc.XAxis.InheritFrom(sbc.styleDefaultsAxes())
axisStyle.WriteToRenderer(r)
cursor := canvasBox.Left
for _, bar := range sbc.Bars {
if len(bar.Name) > 0 {
barLabelBox := Box{
Top: canvasBox.Bottom + DefaultXAxisMargin,
Left: cursor,
Right: cursor + bar.GetWidth() + sbc.GetBarSpacing(),
Bottom: sbc.GetHeight(),
}
lines := Text.WrapFit(r, bar.Name, barLabelBox.Width(), axisStyle)
linesBox := Text.MeasureLines(r, lines, axisStyle)
xaxisHeight = util.Math.MaxInt(linesBox.Height()+(2*DefaultXAxisMargin), xaxisHeight)
}
}
return Box{
Top: canvasBox.Top,
Left: canvasBox.Left,
Right: canvasBox.Left + totalWidth,
Bottom: sbc.GetHeight() - xaxisHeight,
}
}
return Box{
Top: canvasBox.Top,
Left: canvasBox.Left,
Right: canvasBox.Left + totalWidth,
Bottom: canvasBox.Bottom,
}
}
// Box returns the chart bounds as a box.
func (sbc StackedBarChart) Box() Box {
dpr := sbc.Background.Padding.GetRight(10)
dpb := sbc.Background.Padding.GetBottom(50)
return Box{
Top: sbc.Background.Padding.GetTop(20),
Left: sbc.Background.Padding.GetLeft(20),
Right: sbc.GetWidth() - dpr,
Bottom: sbc.GetHeight() - dpb,
}
}
func (sbc StackedBarChart) styleDefaultsStackedBarValue(index int) Style {
return Style{
StrokeColor: sbc.GetColorPalette().GetSeriesColor(index),
StrokeWidth: 3.0,
FillColor: sbc.GetColorPalette().GetSeriesColor(index),
}
}
func (sbc StackedBarChart) styleDefaultsTitle() Style {
return sbc.TitleStyle.InheritFrom(Style{
FontColor: DefaultTextColor,
Font: sbc.GetFont(),
FontSize: sbc.getTitleFontSize(),
TextHorizontalAlign: TextHorizontalAlignCenter,
TextVerticalAlign: TextVerticalAlignTop,
TextWrap: TextWrapWord,
})
}
func (sbc StackedBarChart) getTitleFontSize() float64 {
effectiveDimension := util.Math.MinInt(sbc.GetWidth(), sbc.GetHeight())
if effectiveDimension >= 2048 {
return 48
} else if effectiveDimension >= 1024 {
return 24
} else if effectiveDimension >= 512 {
return 18
} else if effectiveDimension >= 256 {
return 12
}
return 10
}
func (sbc StackedBarChart) styleDefaultsAxes() Style {
return Style{
StrokeColor: DefaultAxisColor,
Font: sbc.GetFont(),
FontSize: DefaultAxisFontSize,
FontColor: DefaultAxisColor,
TextHorizontalAlign: TextHorizontalAlignCenter,
TextVerticalAlign: TextVerticalAlignTop,
TextWrap: TextWrapWord,
}
}
func (sbc StackedBarChart) styleDefaultsElements() Style {
return Style{
Font: sbc.GetFont(),
}
}
package chart
import (
"fmt"
"strings"
"github.com/golang/freetype/truetype"
"github.com/wcharczuk/go-chart/drawing"
"github.com/wcharczuk/go-chart/util"
)
const (
// Disabled indicates if the value should be interpreted as set intentionally to zero.
// this is because golang optionals aren't here yet.
Disabled = -1
)
// StyleShow is a prebuilt style with the `Show` property set to true.
func StyleShow() Style {
return Style{
Show: true,
}
}
// StyleTextDefaults returns a style for drawing outside a
// chart context.
func StyleTextDefaults() Style {
font, _ := GetDefaultFont()
return Style{
Show: true,
Font: font,
FontColor: DefaultTextColor,
FontSize: DefaultTitleFontSize,
}
}
// Style is a simple style set.
type Style struct {
Show bool
Padding Box
ClassName string
StrokeWidth float64
StrokeColor drawing.Color
StrokeDashArray []float64
DotColor drawing.Color
DotWidth float64
DotWidthProvider SizeProvider
DotColorProvider DotColorProvider
FillColor drawing.Color
FontSize float64
FontColor drawing.Color
Font *truetype.Font
TextHorizontalAlign TextHorizontalAlign
TextVerticalAlign TextVerticalAlign
TextWrap TextWrap
TextLineSpacing int
TextRotationDegrees float64 //0 is unset or normal
}
// IsZero returns if the object is set or not.
func (s Style) IsZero() bool {
return s.StrokeColor.IsZero() &&
s.StrokeWidth == 0 &&
s.DotColor.IsZero() &&
s.DotWidth == 0 &&
s.FillColor.IsZero() &&
s.FontColor.IsZero() &&
s.FontSize == 0 &&
s.Font == nil &&
s.ClassName == ""
}
// String returns a text representation of the style.
func (s Style) String() string {
if s.IsZero() {
return "{}"
}
var output []string
if s.Show {
output = []string{"\"show\": true"}
} else {
output = []string{"\"show\": false"}
}
if s.ClassName != "" {
output = append(output, fmt.Sprintf("\"class_name\": %s", s.ClassName))
} else {
output = append(output, "\"class_name\": null")
}
if !s.Padding.IsZero() {
output = append(output, fmt.Sprintf("\"padding\": %s", s.Padding.String()))
} else {
output = append(output, "\"padding\": null")
}
if s.StrokeWidth >= 0 {
output = append(output, fmt.Sprintf("\"stroke_width\": %0.2f", s.StrokeWidth))
} else {
output = append(output, "\"stroke_width\": null")
}
if !s.StrokeColor.IsZero() {
output = append(output, fmt.Sprintf("\"stroke_color\": %s", s.StrokeColor.String()))
} else {
output = append(output, "\"stroke_color\": null")
}
if len(s.StrokeDashArray) > 0 {
var elements []string
for _, v := range s.StrokeDashArray {
elements = append(elements, fmt.Sprintf("%.2f", v))
}
dashArray := strings.Join(elements, ", ")
output = append(output, fmt.Sprintf("\"stroke_dash_array\": [%s]", dashArray))
} else {
output = append(output, "\"stroke_dash_array\": null")
}
if s.DotWidth >= 0 {
output = append(output, fmt.Sprintf("\"dot_width\": %0.2f", s.DotWidth))
} else {
output = append(output, "\"dot_width\": null")
}
if !s.DotColor.IsZero() {
output = append(output, fmt.Sprintf("\"dot_color\": %s", s.DotColor.String()))
} else {
output = append(output, "\"dot_color\": null")
}
if !s.FillColor.IsZero() {
output = append(output, fmt.Sprintf("\"fill_color\": %s", s.FillColor.String()))
} else {
output = append(output, "\"fill_color\": null")
}
if s.FontSize != 0 {
output = append(output, fmt.Sprintf("\"font_size\": \"%0.2fpt\"", s.FontSize))
} else {
output = append(output, "\"font_size\": null")
}
if !s.FontColor.IsZero() {
output = append(output, fmt.Sprintf("\"font_color\": %s", s.FontColor.String()))
} else {
output = append(output, "\"font_color\": null")
}
if s.Font != nil {
output = append(output, fmt.Sprintf("\"font\": \"%s\"", s.Font.Name(truetype.NameIDFontFamily)))
} else {
output = append(output, "\"font_color\": null")
}
return "{" + strings.Join(output, ", ") + "}"
}
func (s Style) GetClassName(defaults ...string) string {
if s.ClassName == "" {
if len(defaults) > 0 {
return defaults[0]
}
return ""
}
return s.ClassName
}
// GetStrokeColor returns the stroke color.
func (s Style) GetStrokeColor(defaults ...drawing.Color) drawing.Color {
if s.StrokeColor.IsZero() {
if len(defaults) > 0 {
return defaults[0]
}
return drawing.ColorTransparent
}
return s.StrokeColor
}
// GetFillColor returns the fill color.
func (s Style) GetFillColor(defaults ...drawing.Color) drawing.Color {
if s.FillColor.IsZero() {
if len(defaults) > 0 {
return defaults[0]
}
return drawing.ColorTransparent
}
return s.FillColor
}
// GetDotColor returns the stroke color.
func (s Style) GetDotColor(defaults ...drawing.Color) drawing.Color {
if s.DotColor.IsZero() {
if len(defaults) > 0 {
return defaults[0]
}
return drawing.ColorTransparent
}
return s.DotColor
}
// GetStrokeWidth returns the stroke width.
func (s Style) GetStrokeWidth(defaults ...float64) float64 {
if s.StrokeWidth == 0 {
if len(defaults) > 0 {
return defaults[0]
}
return DefaultStrokeWidth
}
return s.StrokeWidth
}
// GetDotWidth returns the dot width for scatter plots.
func (s Style) GetDotWidth(defaults ...float64) float64 {
if s.DotWidth == 0 {
if len(defaults) > 0 {
return defaults[0]
}
return DefaultDotWidth
}
return s.DotWidth
}
// GetStrokeDashArray returns the stroke dash array.
func (s Style) GetStrokeDashArray(defaults ...[]float64) []float64 {
if len(s.StrokeDashArray) == 0 {
if len(defaults) > 0 {
return defaults[0]
}
return nil
}
return s.StrokeDashArray
}
// GetFontSize gets the font size.
func (s Style) GetFontSize(defaults ...float64) float64 {
if s.FontSize == 0 {
if len(defaults) > 0 {
return defaults[0]
}
return DefaultFontSize
}
return s.FontSize
}
// GetFontColor gets the font size.
func (s Style) GetFontColor(defaults ...drawing.Color) drawing.Color {
if s.FontColor.IsZero() {
if len(defaults) > 0 {
return defaults[0]
}
return drawing.ColorTransparent
}
return s.FontColor
}
// GetFont returns the font face.
func (s Style) GetFont(defaults ...*truetype.Font) *truetype.Font {
if s.Font == nil {
if len(defaults) > 0 {
return defaults[0]
}
return nil
}
return s.Font
}
// GetPadding returns the padding.
func (s Style) GetPadding(defaults ...Box) Box {
if s.Padding.IsZero() {
if len(defaults) > 0 {
return defaults[0]
}
return Box{}
}
return s.Padding
}
// GetTextHorizontalAlign returns the horizontal alignment.
func (s Style) GetTextHorizontalAlign(defaults ...TextHorizontalAlign) TextHorizontalAlign {
if s.TextHorizontalAlign == TextHorizontalAlignUnset {
if len(defaults) > 0 {
return defaults[0]
}
return TextHorizontalAlignUnset
}
return s.TextHorizontalAlign
}
// GetTextVerticalAlign returns the vertical alignment.
func (s Style) GetTextVerticalAlign(defaults ...TextVerticalAlign) TextVerticalAlign {
if s.TextVerticalAlign == TextVerticalAlignUnset {
if len(defaults) > 0 {
return defaults[0]
}
return TextVerticalAlignUnset
}
return s.TextVerticalAlign
}
// GetTextWrap returns the word wrap.
func (s Style) GetTextWrap(defaults ...TextWrap) TextWrap {
if s.TextWrap == TextWrapUnset {
if len(defaults) > 0 {
return defaults[0]
}
return TextWrapUnset
}
return s.TextWrap
}
// GetTextLineSpacing returns the spacing in pixels between lines of text (vertically).
func (s Style) GetTextLineSpacing(defaults ...int) int {
if s.TextLineSpacing == 0 {
if len(defaults) > 0 {
return defaults[0]
}
return DefaultLineSpacing
}
return s.TextLineSpacing
}
// GetTextRotationDegrees returns the text rotation in degrees.
func (s Style) GetTextRotationDegrees(defaults ...float64) float64 {
if s.TextRotationDegrees == 0 {
if len(defaults) > 0 {
return defaults[0]
}
}
return s.TextRotationDegrees
}
// WriteToRenderer passes the style's options to a renderer.
func (s Style) WriteToRenderer(r Renderer) {
r.SetClassName(s.GetClassName())
r.SetStrokeColor(s.GetStrokeColor())
r.SetStrokeWidth(s.GetStrokeWidth())
r.SetStrokeDashArray(s.GetStrokeDashArray())
r.SetFillColor(s.GetFillColor())
r.SetFont(s.GetFont())
r.SetFontColor(s.GetFontColor())
r.SetFontSize(s.GetFontSize())
r.ClearTextRotation()
if s.GetTextRotationDegrees() != 0 {
r.SetTextRotation(util.Math.DegreesToRadians(s.GetTextRotationDegrees()))
}
}
// WriteDrawingOptionsToRenderer passes just the drawing style options to a renderer.
func (s Style) WriteDrawingOptionsToRenderer(r Renderer) {
r.SetClassName(s.GetClassName())
r.SetStrokeColor(s.GetStrokeColor())
r.SetStrokeWidth(s.GetStrokeWidth())
r.SetStrokeDashArray(s.GetStrokeDashArray())
r.SetFillColor(s.GetFillColor())
}
// WriteTextOptionsToRenderer passes just the text style options to a renderer.
func (s Style) WriteTextOptionsToRenderer(r Renderer) {
r.SetClassName(s.GetClassName())
r.SetFont(s.GetFont())
r.SetFontColor(s.GetFontColor())
r.SetFontSize(s.GetFontSize())
}
// InheritFrom coalesces two styles into a new style.
func (s Style) InheritFrom(defaults Style) (final Style) {
final.ClassName = s.GetClassName(defaults.ClassName)
final.StrokeColor = s.GetStrokeColor(defaults.StrokeColor)
final.StrokeWidth = s.GetStrokeWidth(defaults.StrokeWidth)
final.StrokeDashArray = s.GetStrokeDashArray(defaults.StrokeDashArray)
final.DotColor = s.GetDotColor(defaults.DotColor)
final.DotWidth = s.GetDotWidth(defaults.DotWidth)
final.DotWidthProvider = s.DotWidthProvider
final.DotColorProvider = s.DotColorProvider
final.FillColor = s.GetFillColor(defaults.FillColor)
final.FontColor = s.GetFontColor(defaults.FontColor)
final.FontSize = s.GetFontSize(defaults.FontSize)
final.Font = s.GetFont(defaults.Font)
final.Padding = s.GetPadding(defaults.Padding)
final.TextHorizontalAlign = s.GetTextHorizontalAlign(defaults.TextHorizontalAlign)
final.TextVerticalAlign = s.GetTextVerticalAlign(defaults.TextVerticalAlign)
final.TextWrap = s.GetTextWrap(defaults.TextWrap)
final.TextLineSpacing = s.GetTextLineSpacing(defaults.TextLineSpacing)
final.TextRotationDegrees = s.GetTextRotationDegrees(defaults.TextRotationDegrees)
return
}
// GetStrokeOptions returns the stroke components.
func (s Style) GetStrokeOptions() Style {
return Style{
ClassName: s.ClassName,
StrokeDashArray: s.StrokeDashArray,
StrokeColor: s.StrokeColor,
StrokeWidth: s.StrokeWidth,
}
}
// GetFillOptions returns the fill components.
func (s Style) GetFillOptions() Style {
return Style{
ClassName: s.ClassName,
FillColor: s.FillColor,
}
}
// GetDotOptions returns the dot components.
func (s Style) GetDotOptions() Style {
return Style{
ClassName: s.ClassName,
StrokeDashArray: nil,
FillColor: s.DotColor,
StrokeColor: s.DotColor,
StrokeWidth: 1.0,
}
}
// GetFillAndStrokeOptions returns the fill and stroke components.
func (s Style) GetFillAndStrokeOptions() Style {
return Style{
ClassName: s.ClassName,
StrokeDashArray: s.StrokeDashArray,
FillColor: s.FillColor,
StrokeColor: s.StrokeColor,
StrokeWidth: s.StrokeWidth,
}
}
// GetTextOptions returns just the text components of the style.
func (s Style) GetTextOptions() Style {
return Style{
ClassName: s.ClassName,
FontColor: s.FontColor,
FontSize: s.FontSize,
Font: s.Font,
TextHorizontalAlign: s.TextHorizontalAlign,
TextVerticalAlign: s.TextVerticalAlign,
TextWrap: s.TextWrap,
TextLineSpacing: s.TextLineSpacing,
TextRotationDegrees: s.TextRotationDegrees,
}
}
// ShouldDrawStroke tells drawing functions if they should draw the stroke.
func (s Style) ShouldDrawStroke() bool {
return !s.StrokeColor.IsZero() && s.StrokeWidth > 0
}
// ShouldDrawDot tells drawing functions if they should draw the dot.
func (s Style) ShouldDrawDot() bool {
return (!s.DotColor.IsZero() && s.DotWidth > 0) || s.DotColorProvider != nil || s.DotWidthProvider != nil
}
// ShouldDrawFill tells drawing functions if they should draw the stroke.
func (s Style) ShouldDrawFill() bool {
return !s.FillColor.IsZero()
}
package chart
import (
"strings"
util "github.com/wcharczuk/go-chart/util"
)
// TextHorizontalAlign is an enum for the horizontal alignment options.
type TextHorizontalAlign int
const (
// TextHorizontalAlignUnset is the unset state for text horizontal alignment.
TextHorizontalAlignUnset TextHorizontalAlign = 0
// TextHorizontalAlignLeft aligns a string horizontally so that it's left ligature starts at horizontal pixel 0.
TextHorizontalAlignLeft TextHorizontalAlign = 1
// TextHorizontalAlignCenter left aligns a string horizontally so that there are equal pixels
// to the left and to the right of a string within a box.
TextHorizontalAlignCenter TextHorizontalAlign = 2
// TextHorizontalAlignRight right aligns a string horizontally so that the right ligature ends at the right-most pixel
// of a box.
TextHorizontalAlignRight TextHorizontalAlign = 3
)
// TextWrap is an enum for the word wrap options.
type TextWrap int
const (
// TextWrapUnset is the unset state for text wrap options.
TextWrapUnset TextWrap = 0
// TextWrapNone will spill text past horizontal boundaries.
TextWrapNone TextWrap = 1
// TextWrapWord will split a string on words (i.e. spaces) to fit within a horizontal boundary.
TextWrapWord TextWrap = 2
// TextWrapRune will split a string on a rune (i.e. utf-8 codepage) to fit within a horizontal boundary.
TextWrapRune TextWrap = 3
)
// TextVerticalAlign is an enum for the vertical alignment options.
type TextVerticalAlign int
const (
// TextVerticalAlignUnset is the unset state for vertical alignment options.
TextVerticalAlignUnset TextVerticalAlign = 0
// TextVerticalAlignBaseline aligns text according to the "baseline" of the string, or where a normal ascender begins.
TextVerticalAlignBaseline TextVerticalAlign = 1
// TextVerticalAlignBottom aligns the text according to the lowers pixel of any of the ligatures (ex. g or q both extend below the baseline).
TextVerticalAlignBottom TextVerticalAlign = 2
// TextVerticalAlignMiddle aligns the text so that there is an equal amount of space above and below the top and bottom of the ligatures.
TextVerticalAlignMiddle TextVerticalAlign = 3
// TextVerticalAlignMiddleBaseline aligns the text veritcally so that there is an equal number of pixels above and below the baseline of the string.
TextVerticalAlignMiddleBaseline TextVerticalAlign = 4
// TextVerticalAlignTop alignts the text so that the top of the ligatures are at y-pixel 0 in the container.
TextVerticalAlignTop TextVerticalAlign = 5
)
var (
// Text contains utilities for text.
Text = &text{}
)
// TextStyle encapsulates text style options.
type TextStyle struct {
HorizontalAlign TextHorizontalAlign
VerticalAlign TextVerticalAlign
Wrap TextWrap
}
type text struct{}
func (t text) WrapFit(r Renderer, value string, width int, style Style) []string {
switch style.TextWrap {
case TextWrapRune:
return t.WrapFitRune(r, value, width, style)
case TextWrapWord:
return t.WrapFitWord(r, value, width, style)
}
return []string{value}
}
func (t text) WrapFitWord(r Renderer, value string, width int, style Style) []string {
style.WriteToRenderer(r)
var output []string
var line string
var word string
var textBox Box
for _, c := range value {
if c == rune('\n') { // commit the line to output
output = append(output, t.Trim(line+word))
line = ""
word = ""
continue
}
textBox = r.MeasureText(line + word + string(c))
if textBox.Width() >= width {
output = append(output, t.Trim(line))
line = word
word = string(c)
continue
}
if c == rune(' ') || c == rune('\t') {
line = line + word + string(c)
word = ""
continue
}
word = word + string(c)
}
return append(output, t.Trim(line+word))
}
func (t text) WrapFitRune(r Renderer, value string, width int, style Style) []string {
style.WriteToRenderer(r)
var output []string
var line string
var textBox Box
for _, c := range value {
if c == rune('\n') {
output = append(output, line)
line = ""
continue
}
textBox = r.MeasureText(line + string(c))
if textBox.Width() >= width {
output = append(output, line)
line = string(c)
continue
}
line = line + string(c)
}
return t.appendLast(output, line)
}
func (t text) Trim(value string) string {
return strings.Trim(value, " \t\n\r")
}
func (t text) MeasureLines(r Renderer, lines []string, style Style) Box {
style.WriteTextOptionsToRenderer(r)
var output Box
for index, line := range lines {
lineBox := r.MeasureText(line)
output.Right = util.Math.MaxInt(lineBox.Right, output.Right)
output.Bottom += lineBox.Height()
if index < len(lines)-1 {
output.Bottom += +style.GetTextLineSpacing()
}
}
return output
}
func (t text) appendLast(lines []string, text string) []string {
if len(lines) == 0 {
return []string{text}
}
lastLine := lines[len(lines)-1]
lines[len(lines)-1] = lastLine + text
return lines
}
package chart
import (
"fmt"
"math"
"strings"
util "github.com/wcharczuk/go-chart/util"
)
// TicksProvider is a type that provides ticks.
type TicksProvider interface {
GetTicks(r Renderer, defaults Style, vf ValueFormatter) []Tick
}
// Tick represents a label on an axis.
type Tick struct {
Value float64
Label string
}
// Ticks is an array of ticks.
type Ticks []Tick
// Len returns the length of the ticks set.
func (t Ticks) Len() int {
return len(t)
}
// Swap swaps two elements.
func (t Ticks) Swap(i, j int) {
t[i], t[j] = t[j], t[i]
}
// Less returns if i's value is less than j's value.
func (t Ticks) Less(i, j int) bool {
return t[i].Value < t[j].Value
}
// String returns a string representation of the set of ticks.
func (t Ticks) String() string {
var values []string
for i, tick := range t {
values = append(values, fmt.Sprintf("[%d: %s]", i, tick.Label))
}
return strings.Join(values, ", ")
}
// GenerateContinuousTicks generates a set of ticks.
func GenerateContinuousTicks(r Renderer, ra Range, isVertical bool, style Style, vf ValueFormatter) []Tick {
if vf == nil {
vf = FloatValueFormatter
}
var ticks []Tick
min, max := ra.GetMin(), ra.GetMax()
if ra.IsDescending() {
ticks = append(ticks, Tick{
Value: max,
Label: vf(max),
})
} else {
ticks = append(ticks, Tick{
Value: min,
Label: vf(min),
})
}
minLabel := vf(min)
style.GetTextOptions().WriteToRenderer(r)
labelBox := r.MeasureText(minLabel)
var tickSize float64
if isVertical {
tickSize = float64(labelBox.Height() + DefaultMinimumTickVerticalSpacing)
} else {
tickSize = float64(labelBox.Width() + DefaultMinimumTickHorizontalSpacing)
}
domain := float64(ra.GetDomain())
domainRemainder := domain - (tickSize * 2)
intermediateTickCount := int(math.Floor(float64(domainRemainder) / float64(tickSize)))
rangeDelta := math.Abs(max - min)
tickStep := rangeDelta / float64(intermediateTickCount)
roundTo := util.Math.GetRoundToForDelta(rangeDelta) / 10
intermediateTickCount = util.Math.MinInt(intermediateTickCount, DefaultTickCountSanityCheck)
for x := 1; x < intermediateTickCount; x++ {
var tickValue float64
if ra.IsDescending() {
tickValue = max - util.Math.RoundUp(tickStep*float64(x), roundTo)
} else {
tickValue = min + util.Math.RoundUp(tickStep*float64(x), roundTo)
}
ticks = append(ticks, Tick{
Value: tickValue,
Label: vf(tickValue),
})
}
if ra.IsDescending() {
ticks = append(ticks, Tick{
Value: min,
Label: vf(min),
})
} else {
ticks = append(ticks, Tick{
Value: max,
Label: vf(max),
})
}
return ticks
}
package chart
import (
"fmt"
"time"
util "github.com/wcharczuk/go-chart/util"
)
// Interface Assertions.
var (
_ Series = (*TimeSeries)(nil)
_ FirstValuesProvider = (*TimeSeries)(nil)
_ LastValuesProvider = (*TimeSeries)(nil)
_ ValueFormatterProvider = (*TimeSeries)(nil)
)
// TimeSeries is a line on a chart.
type TimeSeries struct {
Name string
Style Style
YAxis YAxisType
XValues []time.Time
YValues []float64
}
// GetName returns the name of the time series.
func (ts TimeSeries) GetName() string {
return ts.Name
}
// GetStyle returns the line style.
func (ts TimeSeries) GetStyle() Style {
return ts.Style
}
// Len returns the number of elements in the series.
func (ts TimeSeries) Len() int {
return len(ts.XValues)
}
// GetValues gets x, y values at a given index.
func (ts TimeSeries) GetValues(index int) (x, y float64) {
x = util.Time.ToFloat64(ts.XValues[index])
y = ts.YValues[index]
return
}
// GetFirstValues gets the first values.
func (ts TimeSeries) GetFirstValues() (x, y float64) {
x = util.Time.ToFloat64(ts.XValues[0])
y = ts.YValues[0]
return
}
// GetLastValues gets the last values.
func (ts TimeSeries) GetLastValues() (x, y float64) {
x = util.Time.ToFloat64(ts.XValues[len(ts.XValues)-1])
y = ts.YValues[len(ts.YValues)-1]
return
}
// GetValueFormatters returns value formatter defaults for the series.
func (ts TimeSeries) GetValueFormatters() (x, y ValueFormatter) {
x = TimeValueFormatter
y = FloatValueFormatter
return
}
// GetYAxis returns which YAxis the series draws on.
func (ts TimeSeries) GetYAxis() YAxisType {
return ts.YAxis
}
// Render renders the series.
func (ts TimeSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) {
style := ts.Style.InheritFrom(defaults)
Draw.LineSeries(r, canvasBox, xrange, yrange, style, ts)
}
// Validate validates the series.
func (ts TimeSeries) Validate() error {
if len(ts.XValues) == 0 {
return fmt.Errorf("time series must have xvalues set")
}
if len(ts.YValues) == 0 {
return fmt.Errorf("time series must have yvalues set")
}
return nil
}
package util
import (
"time"
)
const (
// AllDaysMask is a bitmask of all the days of the week.
AllDaysMask = 1<<uint(time.Sunday) | 1<<uint(time.Monday) | 1<<uint(time.Tuesday) | 1<<uint(time.Wednesday) | 1<<uint(time.Thursday) | 1<<uint(time.Friday) | 1<<uint(time.Saturday)
// WeekDaysMask is a bitmask of all the weekdays of the week.
WeekDaysMask = 1<<uint(time.Monday) | 1<<uint(time.Tuesday) | 1<<uint(time.Wednesday) | 1<<uint(time.Thursday) | 1<<uint(time.Friday)
//WeekendDaysMask is a bitmask of the weekend days of the week.
WeekendDaysMask = 1<<uint(time.Sunday) | 1<<uint(time.Saturday)
)
var (
// DaysOfWeek are all the time.Weekday in an array for utility purposes.
DaysOfWeek = []time.Weekday{
time.Sunday,
time.Monday,
time.Tuesday,
time.Wednesday,
time.Thursday,
time.Friday,
time.Saturday,
}
// WeekDays are the business time.Weekday in an array.
WeekDays = []time.Weekday{
time.Monday,
time.Tuesday,
time.Wednesday,
time.Thursday,
time.Friday,
}
// WeekendDays are the weekend time.Weekday in an array.
WeekendDays = []time.Weekday{
time.Sunday,
time.Saturday,
}
//Epoch is unix epoc saved for utility purposes.
Epoch = time.Unix(0, 0)
)
// Date contains utility functions that operate on dates.
var Date date
type date struct{}
func (d date) MustEastern() *time.Location {
if eastern, err := d.Eastern(); err != nil {
panic(err)
} else {
return eastern
}
}
// Eastern returns the eastern timezone.
func (d date) Eastern() (*time.Location, error) {
// Try POSIX
est, err := time.LoadLocation("America/New_York")
if err != nil {
// Try Windows
est, err = time.LoadLocation("EST")
if err != nil {
return nil, err
}
}
return est, nil
}
func (d date) MustPacific() *time.Location {
if pst, err := d.Pacific(); err != nil {
panic(err)
} else {
return pst
}
}
// Pacific returns the pacific timezone.
func (d date) Pacific() (*time.Location, error) {
// Try POSIX
pst, err := time.LoadLocation("America/Los_Angeles")
if err != nil {
// Try Windows
pst, err = time.LoadLocation("PST")
if err != nil {
return nil, err
}
}
return pst, nil
}
// TimeUTC returns a new time.Time for the given clock components in UTC.
// It is meant to be used with the `OnDate` function.
func (d date) TimeUTC(hour, min, sec, nsec int) time.Time {
return time.Date(0, 0, 0, hour, min, sec, nsec, time.UTC)
}
// Time returns a new time.Time for the given clock components.
// It is meant to be used with the `OnDate` function.
func (d date) Time(hour, min, sec, nsec int, loc *time.Location) time.Time {
return time.Date(0, 0, 0, hour, min, sec, nsec, loc)
}
// DateUTC returns a new time.Time for the given date comonents at (noon) in UTC.
func (d date) DateUTC(year, month, day int) time.Time {
return time.Date(year, time.Month(month), day, 12, 0, 0, 0, time.UTC)
}
// DateUTC returns a new time.Time for the given date comonents at (noon) in a given location.
func (d date) Date(year, month, day int, loc *time.Location) time.Time {
return time.Date(year, time.Month(month), day, 12, 0, 0, 0, loc)
}
// OnDate returns the clock components of clock (hour,minute,second) on the date components of d.
func (d date) OnDate(clock, date time.Time) time.Time {
tzAdjusted := date.In(clock.Location())
return time.Date(tzAdjusted.Year(), tzAdjusted.Month(), tzAdjusted.Day(), clock.Hour(), clock.Minute(), clock.Second(), clock.Nanosecond(), clock.Location())
}
// NoonOnDate is a shortcut for On(Time(12,0,0), cd) a.k.a. noon on a given date.
func (d date) NoonOnDate(cd time.Time) time.Time {
return time.Date(cd.Year(), cd.Month(), cd.Day(), 12, 0, 0, 0, cd.Location())
}
// IsWeekDay returns if the day is a monday->friday.
func (d date) IsWeekDay(day time.Weekday) bool {
return !d.IsWeekendDay(day)
}
// IsWeekendDay returns if the day is a monday->friday.
func (d date) IsWeekendDay(day time.Weekday) bool {
return day == time.Saturday || day == time.Sunday
}
// Before returns if a timestamp is strictly before another date (ignoring hours, minutes etc.)
func (d date) Before(before, reference time.Time) bool {
tzAdjustedBefore := before.In(reference.Location())
if tzAdjustedBefore.Year() < reference.Year() {
return true
}
if tzAdjustedBefore.Month() < reference.Month() {
return true
}
return tzAdjustedBefore.Year() == reference.Year() && tzAdjustedBefore.Month() == reference.Month() && tzAdjustedBefore.Day() < reference.Day()
}
const (
_secondsPerHour = 60 * 60
_secondsPerDay = 60 * 60 * 24
)
// NextDay returns the timestamp advanced a day.
func (d date) NextDay(ts time.Time) time.Time {
return ts.AddDate(0, 0, 1)
}
// NextHour returns the next timestamp on the hour.
func (d date) NextHour(ts time.Time) time.Time {
//advance a full hour ...
advanced := ts.Add(time.Hour)
minutes := time.Duration(advanced.Minute()) * time.Minute
final := advanced.Add(-minutes)
return time.Date(final.Year(), final.Month(), final.Day(), final.Hour(), 0, 0, 0, final.Location())
}
// NextDayOfWeek returns the next instance of a given weekday after a given timestamp.
func (d date) NextDayOfWeek(after time.Time, dayOfWeek time.Weekday) time.Time {
afterWeekday := after.Weekday()
if afterWeekday == dayOfWeek {
return after.AddDate(0, 0, 7)
}
// 1 vs 5 ~ add 4 days
if afterWeekday < dayOfWeek {
dayDelta := int(dayOfWeek - afterWeekday)
return after.AddDate(0, 0, dayDelta)
}
// 5 vs 1, add 7-(5-1) ~ 3 days
dayDelta := 7 - int(afterWeekday-dayOfWeek)
return after.AddDate(0, 0, dayDelta)
}
package util
import (
"bufio"
"io"
"os"
)
var (
// File contains file utility functions
File = fileUtil{}
)
type fileUtil struct{}
// ReadByLines reads a file and calls the handler for each line.
func (fu fileUtil) ReadByLines(filePath string, handler func(line string) error) error {
var f *os.File
var err error
if f, err = os.Open(filePath); err == nil {
defer f.Close()
var line string
scanner := bufio.NewScanner(f)
for scanner.Scan() {
line = scanner.Text()
err = handler(line)
if err != nil {
return err
}
}
}
return err
}
// ReadByChunks reads a file in `chunkSize` pieces, dispatched to the handler.
func (fu fileUtil) ReadByChunks(filePath string, chunkSize int, handler func(line []byte) error) error {
var f *os.File
var err error
if f, err = os.Open(filePath); err == nil {
defer f.Close()
chunk := make([]byte, chunkSize)
for {
readBytes, err := f.Read(chunk)
if err == io.EOF {
break
}
readData := chunk[:readBytes]
err = handler(readData)
if err != nil {
return err
}
}
}
return err
}
package util
import (
"math"
)
const (
_pi = math.Pi
_2pi = 2 * math.Pi
_3pi4 = (3 * math.Pi) / 4.0
_4pi3 = (4 * math.Pi) / 3.0
_3pi2 = (3 * math.Pi) / 2.0
_5pi4 = (5 * math.Pi) / 4.0
_7pi4 = (7 * math.Pi) / 4.0
_pi2 = math.Pi / 2.0
_pi4 = math.Pi / 4.0
_d2r = (math.Pi / 180.0)
_r2d = (180.0 / math.Pi)
)
var (
// Math contains helper methods for common math operations.
Math = &mathUtil{}
)
type mathUtil struct{}
// Max returns the maximum value of a group of floats.
func (m mathUtil) Max(values ...float64) float64 {
if len(values) == 0 {
return 0
}
max := values[0]
for _, v := range values {
if max < v {
max = v
}
}
return max
}
// MinAndMax returns both the min and max in one pass.
func (m mathUtil) MinAndMax(values ...float64) (min float64, max float64) {
if len(values) == 0 {
return
}
min = values[0]
max = values[0]
for _, v := range values[1:] {
if max < v {
max = v
}
if min > v {
min = v
}
}
return
}
// GetRoundToForDelta returns a `roundTo` value for a given delta.
func (m mathUtil) GetRoundToForDelta(delta float64) float64 {
startingDeltaBound := math.Pow(10.0, 10.0)
for cursor := startingDeltaBound; cursor > 0; cursor /= 10.0 {
if delta > cursor {
return cursor / 10.0
}
}
return 0.0
}
// RoundUp rounds up to a given roundTo value.
func (m mathUtil) RoundUp(value, roundTo float64) float64 {
if roundTo < 0.000000000000001 {
return value
}
d1 := math.Ceil(value / roundTo)
return d1 * roundTo
}
// RoundDown rounds down to a given roundTo value.
func (m mathUtil) RoundDown(value, roundTo float64) float64 {
if roundTo < 0.000000000000001 {
return value
}
d1 := math.Floor(value / roundTo)
return d1 * roundTo
}
// Normalize returns a set of numbers on the interval [0,1] for a given set of inputs.
// An example: 4,3,2,1 => 0.4, 0.3, 0.2, 0.1
// Caveat; the total may be < 1.0; there are going to be issues with irrational numbers etc.
func (m mathUtil) Normalize(values ...float64) []float64 {
var total float64
for _, v := range values {
total += v
}
output := make([]float64, len(values))
for x, v := range values {
output[x] = m.RoundDown(v/total, 0.0001)
}
return output
}
// MinInt returns the minimum of a set of integers.
func (m mathUtil) MinInt(values ...int) int {
min := math.MaxInt32
for _, v := range values {
if v < min {
min = v
}
}
return min
}
// MaxInt returns the maximum of a set of integers.
func (m mathUtil) MaxInt(values ...int) int {
max := math.MinInt32
for _, v := range values {
if v > max {
max = v
}
}
return max
}
// AbsInt returns the absolute value of an integer.
func (m mathUtil) AbsInt(value int) int {
if value < 0 {
return -value
}
return value
}
// AbsInt64 returns the absolute value of a long.
func (m mathUtil) AbsInt64(value int64) int64 {
if value < 0 {
return -value
}
return value
}
// Mean returns the mean of a set of values
func (m mathUtil) Mean(values ...float64) float64 {
return m.Sum(values...) / float64(len(values))
}
// MeanInt returns the mean of a set of integer values.
func (m mathUtil) MeanInt(values ...int) int {
return m.SumInt(values...) / len(values)
}
// Sum sums a set of values.
func (m mathUtil) Sum(values ...float64) float64 {
var total float64
for _, v := range values {
total += v
}
return total
}
// SumInt sums a set of values.
func (m mathUtil) SumInt(values ...int) int {
var total int
for _, v := range values {
total += v
}
return total
}
// PercentDifference computes the percentage difference between two values.
// The formula is (v2-v1)/v1.
func (m mathUtil) PercentDifference(v1, v2 float64) float64 {
if v1 == 0 {
return 0
}
return (v2 - v1) / v1
}
// DegreesToRadians returns degrees as radians.
func (m mathUtil) DegreesToRadians(degrees float64) float64 {
return degrees * _d2r
}
// RadiansToDegrees translates a radian value to a degree value.
func (m mathUtil) RadiansToDegrees(value float64) float64 {
return math.Mod(value, _2pi) * _r2d
}
// PercentToRadians converts a normalized value (0,1) to radians.
func (m mathUtil) PercentToRadians(pct float64) float64 {
return m.DegreesToRadians(360.0 * pct)
}
// RadianAdd adds a delta to a base in radians.
func (m mathUtil) RadianAdd(base, delta float64) float64 {
value := base + delta
if value > _2pi {
return math.Mod(value, _2pi)
} else if value < 0 {
return math.Mod(_2pi+value, _2pi)
}
return value
}
// DegreesAdd adds a delta to a base in radians.
func (m mathUtil) DegreesAdd(baseDegrees, deltaDegrees float64) float64 {
value := baseDegrees + deltaDegrees
if value > _2pi {
return math.Mod(value, 360.0)
} else if value < 0 {
return math.Mod(360.0+value, 360.0)
}
return value
}
// DegreesToCompass returns the degree value in compass / clock orientation.
func (m mathUtil) DegreesToCompass(deg float64) float64 {
return m.DegreesAdd(deg, -90.0)
}
// CirclePoint returns the absolute position of a circle diameter point given
// by the radius and the theta.
func (m mathUtil) CirclePoint(cx, cy int, radius, thetaRadians float64) (x, y int) {
x = cx + int(radius*math.Sin(thetaRadians))
y = cy - int(radius*math.Cos(thetaRadians))
return
}
func (m mathUtil) RotateCoordinate(cx, cy, x, y int, thetaRadians float64) (rx, ry int) {
tempX, tempY := float64(x-cx), float64(y-cy)
rotatedX := tempX*math.Cos(thetaRadians) - tempY*math.Sin(thetaRadians)
rotatedY := tempX*math.Sin(thetaRadians) + tempY*math.Cos(thetaRadians)
rx = int(rotatedX) + cx
ry = int(rotatedY) + cy
return
}
package util
import "time"
var (
// Time contains time utility functions.
Time = timeUtil{}
)
type timeUtil struct{}
// Millis returns the duration as milliseconds.
func (tu timeUtil) Millis(d time.Duration) float64 {
return float64(d) / float64(time.Millisecond)
}
// TimeToFloat64 returns a float64 representation of a time.
func (tu timeUtil) ToFloat64(t time.Time) float64 {
return float64(t.UnixNano())
}
// Float64ToTime returns a time from a float64.
func (tu timeUtil) FromFloat64(tf float64) time.Time {
return time.Unix(0, int64(tf))
}
func (tu timeUtil) DiffDays(t1, t2 time.Time) (days int) {
t1n := t1.Unix()
t2n := t2.Unix()
var diff int64
if t1n > t2n {
diff = t1n - t2n //yields seconds
} else {
diff = t2n - t1n //yields seconds
}
return int(diff / (_secondsPerDay))
}
func (tu timeUtil) DiffHours(t1, t2 time.Time) (hours int) {
t1n := t1.Unix()
t2n := t2.Unix()
var diff int64
if t1n > t2n {
diff = t1n - t2n
} else {
diff = t2n - t1n
}
return int(diff / (_secondsPerHour))
}
// Start returns the earliest (min) time in a list of times.
func (tu timeUtil) Start(times ...time.Time) time.Time {
if len(times) == 0 {
return time.Time{}
}
start := times[0]
for _, t := range times[1:] {
if t.Before(start) {
start = t
}
}
return start
}
// Start returns the earliest (min) time in a list of times.
func (tu timeUtil) End(times ...time.Time) time.Time {
if len(times) == 0 {
return time.Time{}
}
end := times[0]
for _, t := range times[1:] {
if t.After(end) {
end = t
}
}
return end
}
// StartAndEnd returns the start and end of a given set of time in one pass.
func (tu timeUtil) StartAndEnd(values ...time.Time) (start time.Time, end time.Time) {
if len(values) == 0 {
return
}
start = values[0]
end = values[0]
for _, v := range values[1:] {
if end.Before(v) {
end = v
}
if start.After(v) {
start = v
}
}
return
}
package chart
import util "github.com/wcharczuk/go-chart/util"
// Value is a chart value.
type Value struct {
Style Style
Label string
Value float64
}
// Values is an array of Value.
type Values []Value
// Values returns the values.
func (vs Values) Values() []float64 {
values := make([]float64, len(vs))
for index, v := range vs {
values[index] = v.Value
}
return values
}
// ValuesNormalized returns normalized values.
func (vs Values) ValuesNormalized() []float64 {
return util.Math.Normalize(vs.Values()...)
}
// Normalize returns the values normalized.
func (vs Values) Normalize() []Value {
var output []Value
var total float64
for _, v := range vs {
total += v.Value
}
for _, v := range vs {
if v.Value > 0 {
output = append(output, Value{
Style: v.Style,
Label: v.Label,
Value: util.Math.RoundDown(v.Value/total, 0.0001),
})
}
}
return output
}
// Value2 is a two axis value.
type Value2 struct {
Style Style
Label string
XValue, YValue float64
}
package chart
import (
"fmt"
"strconv"
"time"
)
// ValueFormatter is a function that takes a value and produces a string.
type ValueFormatter func(v interface{}) string
// TimeValueFormatter is a ValueFormatter for timestamps.
func TimeValueFormatter(v interface{}) string {
return formatTime(v, DefaultDateFormat)
}
// TimeHourValueFormatter is a ValueFormatter for timestamps.
func TimeHourValueFormatter(v interface{}) string {
return formatTime(v, DefaultDateHourFormat)
}
// TimeMinuteValueFormatter is a ValueFormatter for timestamps.
func TimeMinuteValueFormatter(v interface{}) string {
return formatTime(v, DefaultDateMinuteFormat)
}
// TimeDateValueFormatter is a ValueFormatter for timestamps.
func TimeDateValueFormatter(v interface{}) string {
return formatTime(v, "2006-01-02")
}
// TimeValueFormatterWithFormat returns a time formatter with a given format.
func TimeValueFormatterWithFormat(format string) ValueFormatter {
return func(v interface{}) string {
return formatTime(v, format)
}
}
// TimeValueFormatterWithFormat is a ValueFormatter for timestamps with a given format.
func formatTime(v interface{}, dateFormat string) string {
if typed, isTyped := v.(time.Time); isTyped {
return typed.Format(dateFormat)
}
if typed, isTyped := v.(int64); isTyped {
return time.Unix(0, typed).Format(dateFormat)
}
if typed, isTyped := v.(float64); isTyped {
return time.Unix(0, int64(typed)).Format(dateFormat)
}
return ""
}
// IntValueFormatter is a ValueFormatter for float64.
func IntValueFormatter(v interface{}) string {
switch v.(type) {
case int:
return strconv.Itoa(v.(int))
case int64:
return strconv.FormatInt(v.(int64), 10)
case float32:
return strconv.FormatInt(int64(v.(float32)), 10)
case float64:
return strconv.FormatInt(int64(v.(float64)), 10)
default:
return ""
}
}
// FloatValueFormatter is a ValueFormatter for float64.
func FloatValueFormatter(v interface{}) string {
return FloatValueFormatterWithFormat(v, DefaultFloatFormat)
}
// PercentValueFormatter is a formatter for percent values.
// NOTE: it normalizes the values, i.e. multiplies by 100.0.
func PercentValueFormatter(v interface{}) string {
if typed, isTyped := v.(float64); isTyped {
return FloatValueFormatterWithFormat(typed*100.0, DefaultPercentValueFormat)
}
return ""
}
// FloatValueFormatterWithFormat is a ValueFormatter for float64 with a given format.
func FloatValueFormatterWithFormat(v interface{}, floatFormat string) string {
if typed, isTyped := v.(int); isTyped {
return fmt.Sprintf(floatFormat, float64(typed))
}
if typed, isTyped := v.(int64); isTyped {
return fmt.Sprintf(floatFormat, float64(typed))
}
if typed, isTyped := v.(float32); isTyped {
return fmt.Sprintf(floatFormat, typed)
}
if typed, isTyped := v.(float64); isTyped {
return fmt.Sprintf(floatFormat, typed)
}
return ""
}
package chart
import (
"bytes"
"fmt"
"io"
"math"
"strings"
"golang.org/x/image/font"
"github.com/golang/freetype/truetype"
"github.com/wcharczuk/go-chart/drawing"
"github.com/wcharczuk/go-chart/util"
)
// SVG returns a new png/raster renderer.
func SVG(width, height int) (Renderer, error) {
buffer := bytes.NewBuffer([]byte{})
canvas := newCanvas(buffer)
canvas.Start(width, height)
return &vectorRenderer{
b: buffer,
c: canvas,
s: &Style{},
p: []string{},
dpi: DefaultDPI,
}, nil
}
// vectorRenderer renders chart commands to a bitmap.
type vectorRenderer struct {
dpi float64
b *bytes.Buffer
c *canvas
s *Style
p []string
fc *font.Drawer
}
func (vr *vectorRenderer) ResetStyle() {
vr.s = &Style{Font: vr.s.Font}
vr.fc = nil
}
// GetDPI returns the dpi.
func (vr *vectorRenderer) GetDPI() float64 {
return vr.dpi
}
// SetDPI implements the interface method.
func (vr *vectorRenderer) SetDPI(dpi float64) {
vr.dpi = dpi
vr.c.dpi = dpi
}
// SetClassName implements the interface method.
func (vr *vectorRenderer) SetClassName(classname string) {
vr.s.ClassName = classname
}
// SetStrokeColor implements the interface method.
func (vr *vectorRenderer) SetStrokeColor(c drawing.Color) {
vr.s.StrokeColor = c
}
// SetFillColor implements the interface method.
func (vr *vectorRenderer) SetFillColor(c drawing.Color) {
vr.s.FillColor = c
}
// SetLineWidth implements the interface method.
func (vr *vectorRenderer) SetStrokeWidth(width float64) {
vr.s.StrokeWidth = width
}
// StrokeDashArray sets the stroke dash array.
func (vr *vectorRenderer) SetStrokeDashArray(dashArray []float64) {
vr.s.StrokeDashArray = dashArray
}
// MoveTo implements the interface method.
func (vr *vectorRenderer) MoveTo(x, y int) {
vr.p = append(vr.p, fmt.Sprintf("M %d %d", x, y))
}
// LineTo implements the interface method.
func (vr *vectorRenderer) LineTo(x, y int) {
vr.p = append(vr.p, fmt.Sprintf("L %d %d", x, y))
}
// QuadCurveTo draws a quad curve.
func (vr *vectorRenderer) QuadCurveTo(cx, cy, x, y int) {
vr.p = append(vr.p, fmt.Sprintf("Q%d,%d %d,%d", cx, cy, x, y))
}
func (vr *vectorRenderer) ArcTo(cx, cy int, rx, ry, startAngle, delta float64) {
startAngle = util.Math.RadianAdd(startAngle, _pi2)
endAngle := util.Math.RadianAdd(startAngle, delta)
startx := cx + int(rx*math.Sin(startAngle))
starty := cy - int(ry*math.Cos(startAngle))
if len(vr.p) > 0 {
vr.p = append(vr.p, fmt.Sprintf("L %d %d", startx, starty))
} else {
vr.p = append(vr.p, fmt.Sprintf("M %d %d", startx, starty))
}
endx := cx + int(rx*math.Sin(endAngle))
endy := cy - int(ry*math.Cos(endAngle))
dd := util.Math.RadiansToDegrees(delta)
largeArcFlag := 0
if delta > _pi {
largeArcFlag = 1
}
vr.p = append(vr.p, fmt.Sprintf("A %d %d %0.2f %d 1 %d %d", int(rx), int(ry), dd, largeArcFlag, endx, endy))
}
// Close closes a shape.
func (vr *vectorRenderer) Close() {
vr.p = append(vr.p, fmt.Sprintf("Z"))
}
// Stroke draws the path with no fill.
func (vr *vectorRenderer) Stroke() {
vr.drawPath(vr.s.GetStrokeOptions())
}
// Fill draws the path with no stroke.
func (vr *vectorRenderer) Fill() {
vr.drawPath(vr.s.GetFillOptions())
}
// FillStroke draws the path with both fill and stroke.
func (vr *vectorRenderer) FillStroke() {
vr.drawPath(vr.s.GetFillAndStrokeOptions())
}
// drawPath draws a path.
func (vr *vectorRenderer) drawPath(s Style) {
vr.c.Path(strings.Join(vr.p, "\n"), vr.s.GetFillAndStrokeOptions())
vr.p = []string{} // clear the path
}
// Circle implements the interface method.
func (vr *vectorRenderer) Circle(radius float64, x, y int) {
vr.c.Circle(x, y, int(radius), vr.s.GetFillAndStrokeOptions())
}
// SetFont implements the interface method.
func (vr *vectorRenderer) SetFont(f *truetype.Font) {
vr.s.Font = f
}
// SetFontColor implements the interface method.
func (vr *vectorRenderer) SetFontColor(c drawing.Color) {
vr.s.FontColor = c
}
// SetFontSize implements the interface method.
func (vr *vectorRenderer) SetFontSize(size float64) {
vr.s.FontSize = size
}
// Text draws a text blob.
func (vr *vectorRenderer) Text(body string, x, y int) {
vr.c.Text(x, y, body, vr.s.GetTextOptions())
}
// MeasureText uses the truetype font drawer to measure the width of text.
func (vr *vectorRenderer) MeasureText(body string) (box Box) {
if vr.s.GetFont() != nil {
vr.fc = &font.Drawer{
Face: truetype.NewFace(vr.s.GetFont(), &truetype.Options{
DPI: vr.dpi,
Size: vr.s.FontSize,
}),
}
w := vr.fc.MeasureString(body).Ceil()
box.Right = w
box.Bottom = int(drawing.PointsToPixels(vr.dpi, vr.s.FontSize))
if vr.c.textTheta == nil {
return
}
box = box.Corners().Rotate(util.Math.RadiansToDegrees(*vr.c.textTheta)).Box()
}
return
}
// SetTextRotation sets the text rotation.
func (vr *vectorRenderer) SetTextRotation(radians float64) {
vr.c.textTheta = &radians
}
// ClearTextRotation clears the text rotation.
func (vr *vectorRenderer) ClearTextRotation() {
vr.c.textTheta = nil
}
// Save saves the renderer's contents to a writer.
func (vr *vectorRenderer) Save(w io.Writer) error {
vr.c.End()
_, err := w.Write(vr.b.Bytes())
return err
}
func newCanvas(w io.Writer) *canvas {
return &canvas{
w: w,
dpi: DefaultDPI,
}
}
type canvas struct {
w io.Writer
dpi float64
textTheta *float64
width int
height int
}
func (c *canvas) Start(width, height int) {
c.width = width
c.height = height
c.w.Write([]byte(fmt.Sprintf(`<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="%d" height="%d">\n`, c.width, c.height)))
}
func (c *canvas) Path(d string, style Style) {
var strokeDashArrayProperty string
if len(style.StrokeDashArray) > 0 {
strokeDashArrayProperty = c.getStrokeDashArray(style)
}
c.w.Write([]byte(fmt.Sprintf(`<path %s d="%s" %s/>`, strokeDashArrayProperty, d, c.styleAsSVG(style))))
}
func (c *canvas) Text(x, y int, body string, style Style) {
if c.textTheta == nil {
c.w.Write([]byte(fmt.Sprintf(`<text x="%d" y="%d" %s>%s</text>`, x, y, c.styleAsSVG(style), body)))
} else {
transform := fmt.Sprintf(` transform="rotate(%0.2f,%d,%d)"`, util.Math.RadiansToDegrees(*c.textTheta), x, y)
c.w.Write([]byte(fmt.Sprintf(`<text x="%d" y="%d" %s%s>%s</text>`, x, y, c.styleAsSVG(style), transform, body)))
}
}
func (c *canvas) Circle(x, y, r int, style Style) {
c.w.Write([]byte(fmt.Sprintf(`<circle cx="%d" cy="%d" r="%d" %s/>`, x, y, r, c.styleAsSVG(style))))
}
func (c *canvas) End() {
c.w.Write([]byte("</svg>"))
}
// getStrokeDashArray returns the stroke-dasharray property of a style.
func (c *canvas) getStrokeDashArray(s Style) string {
if len(s.StrokeDashArray) > 0 {
var values []string
for _, v := range s.StrokeDashArray {
values = append(values, fmt.Sprintf("%0.1f", v))
}
return "stroke-dasharray=\"" + strings.Join(values, ", ") + "\""
}
return ""
}
// GetFontFace returns the font face for the style.
func (c *canvas) getFontFace(s Style) string {
family := "sans-serif"
if s.GetFont() != nil {
name := s.GetFont().Name(truetype.NameIDFontFamily)
if len(name) != 0 {
family = fmt.Sprintf(`'%s',%s`, name, family)
}
}
return fmt.Sprintf("font-family:%s", family)
}
// styleAsSVG returns the style as a svg style or class string.
func (c *canvas) styleAsSVG(s Style) string {
if s.ClassName != "" {
return fmt.Sprintf("class=\"%s\"", s.ClassName)
}
sw := s.StrokeWidth
sc := s.StrokeColor
fc := s.FillColor
fs := s.FontSize
fnc := s.FontColor
var pieces []string
if sw != 0 {
pieces = append(pieces, "stroke-width:"+fmt.Sprintf("%d", int(sw)))
} else {
pieces = append(pieces, "stroke-width:0")
}
if !sc.IsZero() {
pieces = append(pieces, "stroke:"+sc.String())
} else {
pieces = append(pieces, "stroke:none")
}
if !fnc.IsZero() {
pieces = append(pieces, "fill:"+fnc.String())
} else if !fc.IsZero() {
pieces = append(pieces, "fill:"+fc.String())
} else {
pieces = append(pieces, "fill:none")
}
if fs != 0 {
pieces = append(pieces, "font-size:"+fmt.Sprintf("%.1fpx", drawing.PointsToPixels(c.dpi, fs)))
}
if s.Font != nil {
pieces = append(pieces, c.getFontFace(s))
}
return fmt.Sprintf("style=\"%s\"", strings.Join(pieces, ";"))
}
package chart
import "github.com/wcharczuk/go-chart/drawing"
var viridisColors = [256]drawing.Color{
drawing.Color{R: 0x44, G: 0x1, B: 0x54, A: 0xff},
drawing.Color{R: 0x44, G: 0x2, B: 0x55, A: 0xff},
drawing.Color{R: 0x45, G: 0x3, B: 0x57, A: 0xff},
drawing.Color{R: 0x45, G: 0x5, B: 0x58, A: 0xff},
drawing.Color{R: 0x45, G: 0x6, B: 0x5a, A: 0xff},
drawing.Color{R: 0x46, G: 0x8, B: 0x5b, A: 0xff},
drawing.Color{R: 0x46, G: 0x9, B: 0x5d, A: 0xff},
drawing.Color{R: 0x46, G: 0xb, B: 0x5e, A: 0xff},
drawing.Color{R: 0x46, G: 0xc, B: 0x60, A: 0xff},
drawing.Color{R: 0x47, G: 0xe, B: 0x61, A: 0xff},
drawing.Color{R: 0x47, G: 0xf, B: 0x62, A: 0xff},
drawing.Color{R: 0x47, G: 0x11, B: 0x64, A: 0xff},
drawing.Color{R: 0x47, G: 0x12, B: 0x65, A: 0xff},
drawing.Color{R: 0x47, G: 0x14, B: 0x66, A: 0xff},
drawing.Color{R: 0x48, G: 0x15, B: 0x68, A: 0xff},
drawing.Color{R: 0x48, G: 0x16, B: 0x69, A: 0xff},
drawing.Color{R: 0x48, G: 0x18, B: 0x6a, A: 0xff},
drawing.Color{R: 0x48, G: 0x19, B: 0x6c, A: 0xff},
drawing.Color{R: 0x48, G: 0x1a, B: 0x6d, A: 0xff},
drawing.Color{R: 0x48, G: 0x1c, B: 0x6e, A: 0xff},
drawing.Color{R: 0x48, G: 0x1d, B: 0x6f, A: 0xff},
drawing.Color{R: 0x48, G: 0x1e, B: 0x70, A: 0xff},
drawing.Color{R: 0x48, G: 0x20, B: 0x71, A: 0xff},
drawing.Color{R: 0x48, G: 0x21, B: 0x73, A: 0xff},
drawing.Color{R: 0x48, G: 0x22, B: 0x74, A: 0xff},
drawing.Color{R: 0x48, G: 0x24, B: 0x75, A: 0xff},
drawing.Color{R: 0x48, G: 0x25, B: 0x76, A: 0xff},
drawing.Color{R: 0x48, G: 0x26, B: 0x77, A: 0xff},
drawing.Color{R: 0x48, G: 0x27, B: 0x78, A: 0xff},
drawing.Color{R: 0x47, G: 0x29, B: 0x79, A: 0xff},
drawing.Color{R: 0x47, G: 0x2a, B: 0x79, A: 0xff},
drawing.Color{R: 0x47, G: 0x2b, B: 0x7a, A: 0xff},
drawing.Color{R: 0x47, G: 0x2c, B: 0x7b, A: 0xff},
drawing.Color{R: 0x47, G: 0x2e, B: 0x7c, A: 0xff},
drawing.Color{R: 0x46, G: 0x2f, B: 0x7d, A: 0xff},
drawing.Color{R: 0x46, G: 0x30, B: 0x7e, A: 0xff},
drawing.Color{R: 0x46, G: 0x31, B: 0x7e, A: 0xff},
drawing.Color{R: 0x46, G: 0x33, B: 0x7f, A: 0xff},
drawing.Color{R: 0x45, G: 0x34, B: 0x80, A: 0xff},
drawing.Color{R: 0x45, G: 0x35, B: 0x81, A: 0xff},
drawing.Color{R: 0x45, G: 0x36, B: 0x81, A: 0xff},
drawing.Color{R: 0x44, G: 0x38, B: 0x82, A: 0xff},
drawing.Color{R: 0x44, G: 0x39, B: 0x83, A: 0xff},
drawing.Color{R: 0x44, G: 0x3a, B: 0x83, A: 0xff},
drawing.Color{R: 0x43, G: 0x3b, B: 0x84, A: 0xff},
drawing.Color{R: 0x43, G: 0x3c, B: 0x84, A: 0xff},
drawing.Color{R: 0x43, G: 0x3e, B: 0x85, A: 0xff},
drawing.Color{R: 0x42, G: 0x3f, B: 0x85, A: 0xff},
drawing.Color{R: 0x42, G: 0x40, B: 0x86, A: 0xff},
drawing.Color{R: 0x41, G: 0x41, B: 0x86, A: 0xff},
drawing.Color{R: 0x41, G: 0x42, B: 0x87, A: 0xff},
drawing.Color{R: 0x41, G: 0x43, B: 0x87, A: 0xff},
drawing.Color{R: 0x40, G: 0x45, B: 0x88, A: 0xff},
drawing.Color{R: 0x40, G: 0x46, B: 0x88, A: 0xff},
drawing.Color{R: 0x3f, G: 0x47, B: 0x88, A: 0xff},
drawing.Color{R: 0x3f, G: 0x48, B: 0x89, A: 0xff},
drawing.Color{R: 0x3e, G: 0x49, B: 0x89, A: 0xff},
drawing.Color{R: 0x3e, G: 0x4a, B: 0x89, A: 0xff},
drawing.Color{R: 0x3d, G: 0x4b, B: 0x8a, A: 0xff},
drawing.Color{R: 0x3d, G: 0x4d, B: 0x8a, A: 0xff},
drawing.Color{R: 0x3c, G: 0x4e, B: 0x8a, A: 0xff},
drawing.Color{R: 0x3c, G: 0x4f, B: 0x8a, A: 0xff},
drawing.Color{R: 0x3b, G: 0x50, B: 0x8b, A: 0xff},
drawing.Color{R: 0x3b, G: 0x51, B: 0x8b, A: 0xff},
drawing.Color{R: 0x3a, G: 0x52, B: 0x8b, A: 0xff},
drawing.Color{R: 0x3a, G: 0x53, B: 0x8b, A: 0xff},
drawing.Color{R: 0x39, G: 0x54, B: 0x8c, A: 0xff},
drawing.Color{R: 0x39, G: 0x55, B: 0x8c, A: 0xff},
drawing.Color{R: 0x38, G: 0x56, B: 0x8c, A: 0xff},
drawing.Color{R: 0x38, G: 0x57, B: 0x8c, A: 0xff},
drawing.Color{R: 0x37, G: 0x58, B: 0x8c, A: 0xff},
drawing.Color{R: 0x37, G: 0x59, B: 0x8c, A: 0xff},
drawing.Color{R: 0x36, G: 0x5b, B: 0x8d, A: 0xff},
drawing.Color{R: 0x36, G: 0x5c, B: 0x8d, A: 0xff},
drawing.Color{R: 0x35, G: 0x5d, B: 0x8d, A: 0xff},
drawing.Color{R: 0x35, G: 0x5e, B: 0x8d, A: 0xff},
drawing.Color{R: 0x34, G: 0x5f, B: 0x8d, A: 0xff},
drawing.Color{R: 0x34, G: 0x60, B: 0x8d, A: 0xff},
drawing.Color{R: 0x33, G: 0x61, B: 0x8d, A: 0xff},
drawing.Color{R: 0x33, G: 0x62, B: 0x8d, A: 0xff},
drawing.Color{R: 0x33, G: 0x63, B: 0x8d, A: 0xff},
drawing.Color{R: 0x32, G: 0x64, B: 0x8e, A: 0xff},
drawing.Color{R: 0x32, G: 0x65, B: 0x8e, A: 0xff},
drawing.Color{R: 0x31, G: 0x66, B: 0x8e, A: 0xff},
drawing.Color{R: 0x31, G: 0x67, B: 0x8e, A: 0xff},
drawing.Color{R: 0x30, G: 0x68, B: 0x8e, A: 0xff},
drawing.Color{R: 0x30, G: 0x69, B: 0x8e, A: 0xff},
drawing.Color{R: 0x2f, G: 0x6a, B: 0x8e, A: 0xff},
drawing.Color{R: 0x2f, G: 0x6b, B: 0x8e, A: 0xff},
drawing.Color{R: 0x2f, G: 0x6c, B: 0x8e, A: 0xff},
drawing.Color{R: 0x2e, G: 0x6d, B: 0x8e, A: 0xff},
drawing.Color{R: 0x2e, G: 0x6e, B: 0x8e, A: 0xff},
drawing.Color{R: 0x2d, G: 0x6f, B: 0x8e, A: 0xff},
drawing.Color{R: 0x2d, G: 0x70, B: 0x8e, A: 0xff},
drawing.Color{R: 0x2d, G: 0x70, B: 0x8e, A: 0xff},
drawing.Color{R: 0x2c, G: 0x71, B: 0x8e, A: 0xff},
drawing.Color{R: 0x2c, G: 0x72, B: 0x8e, A: 0xff},
drawing.Color{R: 0x2b, G: 0x73, B: 0x8e, A: 0xff},
drawing.Color{R: 0x2b, G: 0x74, B: 0x8e, A: 0xff},
drawing.Color{R: 0x2b, G: 0x75, B: 0x8e, A: 0xff},
drawing.Color{R: 0x2a, G: 0x76, B: 0x8e, A: 0xff},
drawing.Color{R: 0x2a, G: 0x77, B: 0x8e, A: 0xff},
drawing.Color{R: 0x29, G: 0x78, B: 0x8e, A: 0xff},
drawing.Color{R: 0x29, G: 0x79, B: 0x8e, A: 0xff},
drawing.Color{R: 0x29, G: 0x7a, B: 0x8e, A: 0xff},
drawing.Color{R: 0x28, G: 0x7b, B: 0x8e, A: 0xff},
drawing.Color{R: 0x28, G: 0x7c, B: 0x8e, A: 0xff},
drawing.Color{R: 0x28, G: 0x7d, B: 0x8e, A: 0xff},
drawing.Color{R: 0x27, G: 0x7e, B: 0x8e, A: 0xff},
drawing.Color{R: 0x27, G: 0x7f, B: 0x8e, A: 0xff},
drawing.Color{R: 0x26, G: 0x80, B: 0x8e, A: 0xff},
drawing.Color{R: 0x26, G: 0x81, B: 0x8e, A: 0xff},
drawing.Color{R: 0x26, G: 0x82, B: 0x8e, A: 0xff},
drawing.Color{R: 0x25, G: 0x83, B: 0x8e, A: 0xff},
drawing.Color{R: 0x25, G: 0x83, B: 0x8e, A: 0xff},
drawing.Color{R: 0x25, G: 0x84, B: 0x8e, A: 0xff},
drawing.Color{R: 0x24, G: 0x85, B: 0x8e, A: 0xff},
drawing.Color{R: 0x24, G: 0x86, B: 0x8e, A: 0xff},
drawing.Color{R: 0x23, G: 0x87, B: 0x8e, A: 0xff},
drawing.Color{R: 0x23, G: 0x88, B: 0x8e, A: 0xff},
drawing.Color{R: 0x23, G: 0x89, B: 0x8e, A: 0xff},
drawing.Color{R: 0x22, G: 0x8a, B: 0x8d, A: 0xff},
drawing.Color{R: 0x22, G: 0x8b, B: 0x8d, A: 0xff},
drawing.Color{R: 0x22, G: 0x8c, B: 0x8d, A: 0xff},
drawing.Color{R: 0x21, G: 0x8d, B: 0x8d, A: 0xff},
drawing.Color{R: 0x21, G: 0x8e, B: 0x8d, A: 0xff},
drawing.Color{R: 0x21, G: 0x8f, B: 0x8d, A: 0xff},
drawing.Color{R: 0x20, G: 0x90, B: 0x8d, A: 0xff},
drawing.Color{R: 0x20, G: 0x91, B: 0x8c, A: 0xff},
drawing.Color{R: 0x20, G: 0x92, B: 0x8c, A: 0xff},
drawing.Color{R: 0x20, G: 0x93, B: 0x8c, A: 0xff},
drawing.Color{R: 0x1f, G: 0x93, B: 0x8c, A: 0xff},
drawing.Color{R: 0x1f, G: 0x94, B: 0x8c, A: 0xff},
drawing.Color{R: 0x1f, G: 0x95, B: 0x8b, A: 0xff},
drawing.Color{R: 0x1f, G: 0x96, B: 0x8b, A: 0xff},
drawing.Color{R: 0x1f, G: 0x97, B: 0x8b, A: 0xff},
drawing.Color{R: 0x1e, G: 0x98, B: 0x8b, A: 0xff},
drawing.Color{R: 0x1e, G: 0x99, B: 0x8a, A: 0xff},
drawing.Color{R: 0x1e, G: 0x9a, B: 0x8a, A: 0xff},
drawing.Color{R: 0x1e, G: 0x9b, B: 0x8a, A: 0xff},
drawing.Color{R: 0x1e, G: 0x9c, B: 0x89, A: 0xff},
drawing.Color{R: 0x1e, G: 0x9d, B: 0x89, A: 0xff},
drawing.Color{R: 0x1e, G: 0x9e, B: 0x89, A: 0xff},
drawing.Color{R: 0x1e, G: 0x9f, B: 0x88, A: 0xff},
drawing.Color{R: 0x1e, G: 0xa0, B: 0x88, A: 0xff},
drawing.Color{R: 0x1f, G: 0xa1, B: 0x88, A: 0xff},
drawing.Color{R: 0x1f, G: 0xa2, B: 0x87, A: 0xff},
drawing.Color{R: 0x1f, G: 0xa3, B: 0x87, A: 0xff},
drawing.Color{R: 0x1f, G: 0xa3, B: 0x86, A: 0xff},
drawing.Color{R: 0x20, G: 0xa4, B: 0x86, A: 0xff},
drawing.Color{R: 0x20, G: 0xa5, B: 0x86, A: 0xff},
drawing.Color{R: 0x21, G: 0xa6, B: 0x85, A: 0xff},
drawing.Color{R: 0x21, G: 0xa7, B: 0x85, A: 0xff},
drawing.Color{R: 0x22, G: 0xa8, B: 0x84, A: 0xff},
drawing.Color{R: 0x23, G: 0xa9, B: 0x83, A: 0xff},
drawing.Color{R: 0x23, G: 0xaa, B: 0x83, A: 0xff},
drawing.Color{R: 0x24, G: 0xab, B: 0x82, A: 0xff},
drawing.Color{R: 0x25, G: 0xac, B: 0x82, A: 0xff},
drawing.Color{R: 0x26, G: 0xad, B: 0x81, A: 0xff},
drawing.Color{R: 0x27, G: 0xae, B: 0x81, A: 0xff},
drawing.Color{R: 0x28, G: 0xaf, B: 0x80, A: 0xff},
drawing.Color{R: 0x29, G: 0xaf, B: 0x7f, A: 0xff},
drawing.Color{R: 0x2a, G: 0xb0, B: 0x7f, A: 0xff},
drawing.Color{R: 0x2b, G: 0xb1, B: 0x7e, A: 0xff},
drawing.Color{R: 0x2c, G: 0xb2, B: 0x7d, A: 0xff},
drawing.Color{R: 0x2e, G: 0xb3, B: 0x7c, A: 0xff},
drawing.Color{R: 0x2f, G: 0xb4, B: 0x7c, A: 0xff},
drawing.Color{R: 0x30, G: 0xb5, B: 0x7b, A: 0xff},
drawing.Color{R: 0x32, G: 0xb6, B: 0x7a, A: 0xff},
drawing.Color{R: 0x33, G: 0xb7, B: 0x79, A: 0xff},
drawing.Color{R: 0x35, G: 0xb7, B: 0x79, A: 0xff},
drawing.Color{R: 0x36, G: 0xb8, B: 0x78, A: 0xff},
drawing.Color{R: 0x38, G: 0xb9, B: 0x77, A: 0xff},
drawing.Color{R: 0x39, G: 0xba, B: 0x76, A: 0xff},
drawing.Color{R: 0x3b, G: 0xbb, B: 0x75, A: 0xff},
drawing.Color{R: 0x3d, G: 0xbc, B: 0x74, A: 0xff},
drawing.Color{R: 0x3e, G: 0xbd, B: 0x73, A: 0xff},
drawing.Color{R: 0x40, G: 0xbe, B: 0x72, A: 0xff},
drawing.Color{R: 0x42, G: 0xbe, B: 0x71, A: 0xff},
drawing.Color{R: 0x44, G: 0xbf, B: 0x70, A: 0xff},
drawing.Color{R: 0x46, G: 0xc0, B: 0x6f, A: 0xff},
drawing.Color{R: 0x48, G: 0xc1, B: 0x6e, A: 0xff},
drawing.Color{R: 0x49, G: 0xc2, B: 0x6d, A: 0xff},
drawing.Color{R: 0x4b, G: 0xc2, B: 0x6c, A: 0xff},
drawing.Color{R: 0x4d, G: 0xc3, B: 0x6b, A: 0xff},
drawing.Color{R: 0x4f, G: 0xc4, B: 0x6a, A: 0xff},
drawing.Color{R: 0x51, G: 0xc5, B: 0x69, A: 0xff},
drawing.Color{R: 0x53, G: 0xc6, B: 0x68, A: 0xff},
drawing.Color{R: 0x55, G: 0xc6, B: 0x66, A: 0xff},
drawing.Color{R: 0x58, G: 0xc7, B: 0x65, A: 0xff},
drawing.Color{R: 0x5a, G: 0xc8, B: 0x64, A: 0xff},
drawing.Color{R: 0x5c, G: 0xc9, B: 0x63, A: 0xff},
drawing.Color{R: 0x5e, G: 0xc9, B: 0x62, A: 0xff},
drawing.Color{R: 0x60, G: 0xca, B: 0x60, A: 0xff},
drawing.Color{R: 0x62, G: 0xcb, B: 0x5f, A: 0xff},
drawing.Color{R: 0x65, G: 0xcc, B: 0x5e, A: 0xff},
drawing.Color{R: 0x67, G: 0xcc, B: 0x5c, A: 0xff},
drawing.Color{R: 0x69, G: 0xcd, B: 0x5b, A: 0xff},
drawing.Color{R: 0x6c, G: 0xce, B: 0x5a, A: 0xff},
drawing.Color{R: 0x6e, G: 0xce, B: 0x58, A: 0xff},
drawing.Color{R: 0x70, G: 0xcf, B: 0x57, A: 0xff},
drawing.Color{R: 0x73, G: 0xd0, B: 0x55, A: 0xff},
drawing.Color{R: 0x75, G: 0xd0, B: 0x54, A: 0xff},
drawing.Color{R: 0x77, G: 0xd1, B: 0x52, A: 0xff},
drawing.Color{R: 0x7a, G: 0xd2, B: 0x51, A: 0xff},
drawing.Color{R: 0x7c, G: 0xd2, B: 0x4f, A: 0xff},
drawing.Color{R: 0x7f, G: 0xd3, B: 0x4e, A: 0xff},
drawing.Color{R: 0x81, G: 0xd4, B: 0x4c, A: 0xff},
drawing.Color{R: 0x84, G: 0xd4, B: 0x4b, A: 0xff},
drawing.Color{R: 0x86, G: 0xd5, B: 0x49, A: 0xff},
drawing.Color{R: 0x89, G: 0xd5, B: 0x48, A: 0xff},
drawing.Color{R: 0x8b, G: 0xd6, B: 0x46, A: 0xff},
drawing.Color{R: 0x8e, G: 0xd7, B: 0x44, A: 0xff},
drawing.Color{R: 0x90, G: 0xd7, B: 0x43, A: 0xff},
drawing.Color{R: 0x93, G: 0xd8, B: 0x41, A: 0xff},
drawing.Color{R: 0x95, G: 0xd8, B: 0x3f, A: 0xff},
drawing.Color{R: 0x98, G: 0xd9, B: 0x3e, A: 0xff},
drawing.Color{R: 0x9b, G: 0xd9, B: 0x3c, A: 0xff},
drawing.Color{R: 0x9d, G: 0xda, B: 0x3a, A: 0xff},
drawing.Color{R: 0xa0, G: 0xda, B: 0x39, A: 0xff},
drawing.Color{R: 0xa3, G: 0xdb, B: 0x37, A: 0xff},
drawing.Color{R: 0xa5, G: 0xdb, B: 0x35, A: 0xff},
drawing.Color{R: 0xa8, G: 0xdc, B: 0x33, A: 0xff},
drawing.Color{R: 0xab, G: 0xdc, B: 0x32, A: 0xff},
drawing.Color{R: 0xad, G: 0xdd, B: 0x30, A: 0xff},
drawing.Color{R: 0xb0, G: 0xdd, B: 0x2e, A: 0xff},
drawing.Color{R: 0xb3, G: 0xdd, B: 0x2d, A: 0xff},
drawing.Color{R: 0xb5, G: 0xde, B: 0x2b, A: 0xff},
drawing.Color{R: 0xb8, G: 0xde, B: 0x29, A: 0xff},
drawing.Color{R: 0xbb, G: 0xdf, B: 0x27, A: 0xff},
drawing.Color{R: 0xbd, G: 0xdf, B: 0x26, A: 0xff},
drawing.Color{R: 0xc0, G: 0xdf, B: 0x24, A: 0xff},
drawing.Color{R: 0xc3, G: 0xe0, B: 0x23, A: 0xff},
drawing.Color{R: 0xc5, G: 0xe0, B: 0x21, A: 0xff},
drawing.Color{R: 0xc8, G: 0xe1, B: 0x20, A: 0xff},
drawing.Color{R: 0xcb, G: 0xe1, B: 0x1e, A: 0xff},
drawing.Color{R: 0xcd, G: 0xe1, B: 0x1d, A: 0xff},
drawing.Color{R: 0xd0, G: 0xe2, B: 0x1c, A: 0xff},
drawing.Color{R: 0xd3, G: 0xe2, B: 0x1b, A: 0xff},
drawing.Color{R: 0xd5, G: 0xe2, B: 0x1a, A: 0xff},
drawing.Color{R: 0xd8, G: 0xe3, B: 0x19, A: 0xff},
drawing.Color{R: 0xdb, G: 0xe3, B: 0x18, A: 0xff},
drawing.Color{R: 0xdd, G: 0xe3, B: 0x18, A: 0xff},
drawing.Color{R: 0xe0, G: 0xe4, B: 0x18, A: 0xff},
drawing.Color{R: 0xe2, G: 0xe4, B: 0x18, A: 0xff},
drawing.Color{R: 0xe5, G: 0xe4, B: 0x18, A: 0xff},
drawing.Color{R: 0xe8, G: 0xe5, B: 0x19, A: 0xff},
drawing.Color{R: 0xea, G: 0xe5, B: 0x19, A: 0xff},
drawing.Color{R: 0xed, G: 0xe5, B: 0x1a, A: 0xff},
drawing.Color{R: 0xef, G: 0xe6, B: 0x1b, A: 0xff},
drawing.Color{R: 0xf2, G: 0xe6, B: 0x1c, A: 0xff},
drawing.Color{R: 0xf4, G: 0xe6, B: 0x1e, A: 0xff},
drawing.Color{R: 0xf7, G: 0xe6, B: 0x1f, A: 0xff},
drawing.Color{R: 0xf9, G: 0xe7, B: 0x21, A: 0xff},
drawing.Color{R: 0xfb, G: 0xe7, B: 0x23, A: 0xff},
drawing.Color{R: 0xfe, G: 0xe7, B: 0x24, A: 0xff},
}
// Viridis creates a color map provider.
func Viridis(v, vmin, vmax float64) drawing.Color {
normalized := (v - vmin) / (vmax - vmin)
index := uint8(normalized * 255)
return viridisColors[index]
}
package chart
import (
"math"
util "github.com/wcharczuk/go-chart/util"
)
// XAxis represents the horizontal axis.
type XAxis struct {
Name string
NameStyle Style
Style Style
ValueFormatter ValueFormatter
Range Range
TickStyle Style
Ticks []Tick
TickPosition TickPosition
GridLines []GridLine
GridMajorStyle Style
GridMinorStyle Style
}
// GetName returns the name.
func (xa XAxis) GetName() string {
return xa.Name
}
// GetStyle returns the style.
func (xa XAxis) GetStyle() Style {
return xa.Style
}
// GetValueFormatter returns the value formatter for the axis.
func (xa XAxis) GetValueFormatter() ValueFormatter {
if xa.ValueFormatter != nil {
return xa.ValueFormatter
}
return FloatValueFormatter
}
// GetTickPosition returns the tick position option for the axis.
func (xa XAxis) GetTickPosition(defaults ...TickPosition) TickPosition {
if xa.TickPosition == TickPositionUnset {
if len(defaults) > 0 {
return defaults[0]
}
return TickPositionUnderTick
}
return xa.TickPosition
}
// GetTicks returns the ticks for a series.
// The coalesce priority is:
// - User Supplied Ticks (i.e. Ticks array on the axis itself).
// - Range ticks (i.e. if the range provides ticks).
// - Generating continuous ticks based on minimum spacing and canvas width.
func (xa XAxis) GetTicks(r Renderer, ra Range, defaults Style, vf ValueFormatter) []Tick {
if len(xa.Ticks) > 0 {
return xa.Ticks
}
if tp, isTickProvider := ra.(TicksProvider); isTickProvider {
return tp.GetTicks(r, defaults, vf)
}
tickStyle := xa.Style.InheritFrom(defaults)
return GenerateContinuousTicks(r, ra, false, tickStyle, vf)
}
// GetGridLines returns the gridlines for the axis.
func (xa XAxis) GetGridLines(ticks []Tick) []GridLine {
if len(xa.GridLines) > 0 {
return xa.GridLines
}
return GenerateGridLines(ticks, xa.GridMajorStyle, xa.GridMinorStyle)
}
// Measure returns the bounds of the axis.
func (xa XAxis) Measure(r Renderer, canvasBox Box, ra Range, defaults Style, ticks []Tick) Box {
tickStyle := xa.TickStyle.InheritFrom(xa.Style.InheritFrom(defaults))
tp := xa.GetTickPosition()
var ltx, rtx int
var tx, ty int
var left, right, bottom = math.MaxInt32, 0, 0
for index, t := range ticks {
v := t.Value
tb := Draw.MeasureText(r, t.Label, tickStyle.GetTextOptions())
tx = canvasBox.Left + ra.Translate(v)
ty = canvasBox.Bottom + DefaultXAxisMargin + tb.Height()
switch tp {
case TickPositionUnderTick, TickPositionUnset:
ltx = tx - tb.Width()>>1
rtx = tx + tb.Width()>>1
break
case TickPositionBetweenTicks:
if index > 0 {
ltx = ra.Translate(ticks[index-1].Value)
rtx = tx
}
break
}
left = util.Math.MinInt(left, ltx)
right = util.Math.MaxInt(right, rtx)
bottom = util.Math.MaxInt(bottom, ty)
}
if xa.NameStyle.Show && len(xa.Name) > 0 {
tb := Draw.MeasureText(r, xa.Name, xa.NameStyle.InheritFrom(defaults))
bottom += DefaultXAxisMargin + tb.Height()
}
return Box{
Top: canvasBox.Bottom,
Left: left,
Right: right,
Bottom: bottom,
}
}
// Render renders the axis
func (xa XAxis) Render(r Renderer, canvasBox Box, ra Range, defaults Style, ticks []Tick) {
tickStyle := xa.TickStyle.InheritFrom(xa.Style.InheritFrom(defaults))
tickStyle.GetStrokeOptions().WriteToRenderer(r)
r.MoveTo(canvasBox.Left, canvasBox.Bottom)
r.LineTo(canvasBox.Right, canvasBox.Bottom)
r.Stroke()
tp := xa.GetTickPosition()
var tx, ty int
var maxTextHeight int
for index, t := range ticks {
v := t.Value
lx := ra.Translate(v)
tx = canvasBox.Left + lx
tickStyle.GetStrokeOptions().WriteToRenderer(r)
r.MoveTo(tx, canvasBox.Bottom)
r.LineTo(tx, canvasBox.Bottom+DefaultVerticalTickHeight)
r.Stroke()
tickWithAxisStyle := xa.TickStyle.InheritFrom(xa.Style.InheritFrom(defaults))
tb := Draw.MeasureText(r, t.Label, tickWithAxisStyle)
switch tp {
case TickPositionUnderTick, TickPositionUnset:
if tickStyle.TextRotationDegrees == 0 {
tx = tx - tb.Width()>>1
ty = canvasBox.Bottom + DefaultXAxisMargin + tb.Height()
} else {
ty = canvasBox.Bottom + (2 * DefaultXAxisMargin)
}
Draw.Text(r, t.Label, tx, ty, tickWithAxisStyle)
maxTextHeight = util.Math.MaxInt(maxTextHeight, tb.Height())
break
case TickPositionBetweenTicks:
if index > 0 {
llx := ra.Translate(ticks[index-1].Value)
ltx := canvasBox.Left + llx
finalTickStyle := tickWithAxisStyle.InheritFrom(Style{TextHorizontalAlign: TextHorizontalAlignCenter})
Draw.TextWithin(r, t.Label, Box{
Left: ltx,
Right: tx,
Top: canvasBox.Bottom + DefaultXAxisMargin,
Bottom: canvasBox.Bottom + DefaultXAxisMargin,
}, finalTickStyle)
ftb := Text.MeasureLines(r, Text.WrapFit(r, t.Label, tx-ltx, finalTickStyle), finalTickStyle)
maxTextHeight = util.Math.MaxInt(maxTextHeight, ftb.Height())
}
break
}
}
nameStyle := xa.NameStyle.InheritFrom(defaults)
if xa.NameStyle.Show && len(xa.Name) > 0 {
tb := Draw.MeasureText(r, xa.Name, nameStyle)
tx := canvasBox.Right - (canvasBox.Width()>>1 + tb.Width()>>1)
ty := canvasBox.Bottom + DefaultXAxisMargin + maxTextHeight + DefaultXAxisMargin + tb.Height()
Draw.Text(r, xa.Name, tx, ty, nameStyle)
}
if xa.GridMajorStyle.Show || xa.GridMinorStyle.Show {
for _, gl := range xa.GetGridLines(ticks) {
if (gl.IsMinor && xa.GridMinorStyle.Show) || (!gl.IsMinor && xa.GridMajorStyle.Show) {
defaults := xa.GridMajorStyle
if gl.IsMinor {
defaults = xa.GridMinorStyle
}
gl.Render(r, canvasBox, ra, true, gl.Style.InheritFrom(defaults))
}
}
}
}
package chart
import (
"math"
util "github.com/wcharczuk/go-chart/util"
)
// YAxis is a veritcal rule of the range.
// There can be (2) y-axes; a primary and secondary.
type YAxis struct {
Name string
NameStyle Style
Style Style
Zero GridLine
AxisType YAxisType
Ascending bool
ValueFormatter ValueFormatter
Range Range
TickStyle Style
Ticks []Tick
GridLines []GridLine
GridMajorStyle Style
GridMinorStyle Style
}
// GetName returns the name.
func (ya YAxis) GetName() string {
return ya.Name
}
// GetNameStyle returns the name style.
func (ya YAxis) GetNameStyle() Style {
return ya.NameStyle
}
// GetStyle returns the style.
func (ya YAxis) GetStyle() Style {
return ya.Style
}
// GetValueFormatter returns the value formatter for the axis.
func (ya YAxis) GetValueFormatter() ValueFormatter {
if ya.ValueFormatter != nil {
return ya.ValueFormatter
}
return FloatValueFormatter
}
// GetTickStyle returns the tick style.
func (ya YAxis) GetTickStyle() Style {
return ya.TickStyle
}
// GetTicks returns the ticks for a series.
// The coalesce priority is:
// - User Supplied Ticks (i.e. Ticks array on the axis itself).
// - Range ticks (i.e. if the range provides ticks).
// - Generating continuous ticks based on minimum spacing and canvas width.
func (ya YAxis) GetTicks(r Renderer, ra Range, defaults Style, vf ValueFormatter) []Tick {
if len(ya.Ticks) > 0 {
return ya.Ticks
}
if tp, isTickProvider := ra.(TicksProvider); isTickProvider {
return tp.GetTicks(r, defaults, vf)
}
tickStyle := ya.Style.InheritFrom(defaults)
return GenerateContinuousTicks(r, ra, true, tickStyle, vf)
}
// GetGridLines returns the gridlines for the axis.
func (ya YAxis) GetGridLines(ticks []Tick) []GridLine {
if len(ya.GridLines) > 0 {
return ya.GridLines
}
return GenerateGridLines(ticks, ya.GridMajorStyle, ya.GridMinorStyle)
}
// Measure returns the bounds of the axis.
func (ya YAxis) Measure(r Renderer, canvasBox Box, ra Range, defaults Style, ticks []Tick) Box {
var tx int
if ya.AxisType == YAxisPrimary {
tx = canvasBox.Right + DefaultYAxisMargin
} else if ya.AxisType == YAxisSecondary {
tx = canvasBox.Left - DefaultYAxisMargin
}
ya.TickStyle.InheritFrom(ya.Style.InheritFrom(defaults)).WriteToRenderer(r)
var minx, maxx, miny, maxy = math.MaxInt32, 0, math.MaxInt32, 0
var maxTextHeight int
for _, t := range ticks {
v := t.Value
ly := canvasBox.Bottom - ra.Translate(v)
tb := r.MeasureText(t.Label)
tbh2 := tb.Height() >> 1
finalTextX := tx
if ya.AxisType == YAxisSecondary {
finalTextX = tx - tb.Width()
}
maxTextHeight = util.Math.MaxInt(tb.Height(), maxTextHeight)
if ya.AxisType == YAxisPrimary {
minx = canvasBox.Right
maxx = util.Math.MaxInt(maxx, tx+tb.Width())
} else if ya.AxisType == YAxisSecondary {
minx = util.Math.MinInt(minx, finalTextX)
maxx = util.Math.MaxInt(maxx, tx)
}
miny = util.Math.MinInt(miny, ly-tbh2)
maxy = util.Math.MaxInt(maxy, ly+tbh2)
}
if ya.NameStyle.Show && len(ya.Name) > 0 {
maxx += (DefaultYAxisMargin + maxTextHeight)
}
return Box{
Top: miny,
Left: minx,
Right: maxx,
Bottom: maxy,
}
}
// Render renders the axis.
func (ya YAxis) Render(r Renderer, canvasBox Box, ra Range, defaults Style, ticks []Tick) {
tickStyle := ya.TickStyle.InheritFrom(ya.Style.InheritFrom(defaults))
tickStyle.WriteToRenderer(r)
sw := tickStyle.GetStrokeWidth(defaults.StrokeWidth)
var lx int
var tx int
if ya.AxisType == YAxisPrimary {
lx = canvasBox.Right + int(sw)
tx = lx + DefaultYAxisMargin
} else if ya.AxisType == YAxisSecondary {
lx = canvasBox.Left - int(sw)
tx = lx - DefaultYAxisMargin
}
r.MoveTo(lx, canvasBox.Bottom)
r.LineTo(lx, canvasBox.Top)
r.Stroke()
var maxTextWidth int
var finalTextX, finalTextY int
for _, t := range ticks {
v := t.Value
ly := canvasBox.Bottom - ra.Translate(v)
tb := Draw.MeasureText(r, t.Label, tickStyle)
if tb.Width() > maxTextWidth {
maxTextWidth = tb.Width()
}
if ya.AxisType == YAxisSecondary {
finalTextX = tx - tb.Width()
} else {
finalTextX = tx
}
if tickStyle.TextRotationDegrees == 0 {
finalTextY = ly + tb.Height()>>1
} else {
finalTextY = ly
}
tickStyle.WriteToRenderer(r)
r.MoveTo(lx, ly)
if ya.AxisType == YAxisPrimary {
r.LineTo(lx+DefaultHorizontalTickWidth, ly)
} else if ya.AxisType == YAxisSecondary {
r.LineTo(lx-DefaultHorizontalTickWidth, ly)
}
r.Stroke()
Draw.Text(r, t.Label, finalTextX, finalTextY, tickStyle)
}
nameStyle := ya.NameStyle.InheritFrom(defaults.InheritFrom(Style{TextRotationDegrees: 90}))
if ya.NameStyle.Show && len(ya.Name) > 0 {
nameStyle.GetTextOptions().WriteToRenderer(r)
tb := Draw.MeasureText(r, ya.Name, nameStyle)
var tx int
if ya.AxisType == YAxisPrimary {
tx = canvasBox.Right + int(sw) + DefaultYAxisMargin + maxTextWidth + DefaultYAxisMargin
} else if ya.AxisType == YAxisSecondary {
tx = canvasBox.Left - (DefaultYAxisMargin + int(sw) + maxTextWidth + DefaultYAxisMargin)
}
var ty int
if nameStyle.TextRotationDegrees == 0 {
ty = canvasBox.Top + (canvasBox.Height()>>1 - tb.Width()>>1)
} else {
ty = canvasBox.Top + (canvasBox.Height()>>1 - tb.Height()>>1)
}
Draw.Text(r, ya.Name, tx, ty, nameStyle)
}
if ya.Zero.Style.Show {
ya.Zero.Render(r, canvasBox, ra, false, Style{})
}
if ya.GridMajorStyle.Show || ya.GridMinorStyle.Show {
for _, gl := range ya.GetGridLines(ticks) {
if (gl.IsMinor && ya.GridMinorStyle.Show) || (!gl.IsMinor && ya.GridMajorStyle.Show) {
defaults := ya.GridMajorStyle
if gl.IsMinor {
defaults = ya.GridMinorStyle
}
gl.Render(r, canvasBox, ra, false, gl.Style.InheritFrom(defaults))
}
}
}
}