getting ready to add extended colors but stopping at basic colors for now

_colors/colors_extended.txt

@@ -0,0 +1,147 @@
+aliceblue 	#f0f8ff 	240,248,255
+antiquewhite 	#faebd7 	250,235,215
+aqua 	#00ffff 	0,255,255
+aquamarine 	#7fffd4 	127,255,212
+azure 	#f0ffff 	240,255,255
+beige 	#f5f5dc 	245,245,220
+bisque 	#ffe4c4 	255,228,196
+black 	#000000 	0,0,0
+blanchedalmond 	#ffebcd 	255,235,205
+blue 	#0000ff 	0,0,255
+blueviolet 	#8a2be2 	138,43,226
+brown 	#a52a2a 	165,42,42
+burlywood 	#deb887 	222,184,135
+cadetblue 	#5f9ea0 	95,158,160
+chartreuse 	#7fff00 	127,255,0
+chocolate 	#d2691e 	210,105,30
+coral 	#ff7f50 	255,127,80
+cornflowerblue 	#6495ed 	100,149,237
+cornsilk 	#fff8dc 	255,248,220
+crimson 	#dc143c 	220,20,60
+cyan 	#00ffff 	0,255,255
+darkblue 	#00008b 	0,0,139
+darkcyan 	#008b8b 	0,139,139
+darkgoldenrod 	#b8860b 	184,134,11
+darkgray 	#a9a9a9 	169,169,169
+darkgreen 	#006400 	0,100,0
+darkgrey 	#a9a9a9 	169,169,169
+darkkhaki 	#bdb76b 	189,183,107
+darkmagenta 	#8b008b 	139,0,139
+darkolivegreen 	#556b2f 	85,107,47
+darkorange 	#ff8c00 	255,140,0
+darkorchid 	#9932cc 	153,50,204
+darkred 	#8b0000 	139,0,0
+darksalmon 	#e9967a 	233,150,122
+darkseagreen 	#8fbc8f 	143,188,143
+darkslateblue 	#483d8b 	72,61,139
+darkslategray 	#2f4f4f 	47,79,79
+darkslategrey 	#2f4f4f 	47,79,79
+darkturquoise 	#00ced1 	0,206,209
+darkviolet 	#9400d3 	148,0,211
+deeppink 	#ff1493 	255,20,147
+deepskyblue 	#00bfff 	0,191,255
+dimgray 	#696969 	105,105,105
+dimgrey 	#696969 	105,105,105
+dodgerblue 	#1e90ff 	30,144,255
+firebrick 	#b22222 	178,34,34
+floralwhite 	#fffaf0 	255,250,240
+forestgreen 	#228b22 	34,139,34
+fuchsia 	#ff00ff 	255,0,255
+gainsboro 	#dcdcdc 	220,220,220
+ghostwhite 	#f8f8ff 	248,248,255
+gold 	#ffd700 	255,215,0
+goldenrod 	#daa520 	218,165,32
+gray 	#808080 	128,128,128
+green 	#008000 	0,128,0
+greenyellow 	#adff2f 	173,255,47
+grey 	#808080 	128,128,128
+honeydew 	#f0fff0 	240,255,240
+hotpink 	#ff69b4 	255,105,180
+indianred 	#cd5c5c 	205,92,92
+indigo 	#4b0082 	75,0,130
+ivory 	#fffff0 	255,255,240
+khaki 	#f0e68c 	240,230,140
+lavender 	#e6e6fa 	230,230,250
+lavenderblush 	#fff0f5 	255,240,245
+lawngreen 	#7cfc00 	124,252,0
+lemonchiffon 	#fffacd 	255,250,205
+lightblue 	#add8e6 	173,216,230
+lightcoral 	#f08080 	240,128,128
+lightcyan 	#e0ffff 	224,255,255
+lightgoldenrodyellow 	#fafad2 	250,250,210
+lightgray 	#d3d3d3 	211,211,211
+lightgreen 	#90ee90 	144,238,144
+lightgrey 	#d3d3d3 	211,211,211
+lightpink 	#ffb6c1 	255,182,193
+lightsalmon 	#ffa07a 	255,160,122
+lightseagreen 	#20b2aa 	32,178,170
+lightskyblue 	#87cefa 	135,206,250
+lightslategray 	#778899 	119,136,153
+lightslategrey 	#778899 	119,136,153
+lightsteelblue 	#b0c4de 	176,196,222
+lightyellow 	#ffffe0 	255,255,224
+lime 	#00ff00 	0,255,0
+limegreen 	#32cd32 	50,205,50
+linen 	#faf0e6 	250,240,230
+magenta 	#ff00ff 	255,0,255
+maroon 	#800000 	128,0,0
+mediumaquamarine 	#66cdaa 	102,205,170
+mediumblue 	#0000cd 	0,0,205
+mediumorchid 	#ba55d3 	186,85,211
+mediumpurple 	#9370db 	147,112,219
+mediumseagreen 	#3cb371 	60,179,113
+mediumslateblue 	#7b68ee 	123,104,238
+mediumspringgreen 	#00fa9a 	0,250,154
+mediumturquoise 	#48d1cc 	72,209,204
+mediumvioletred 	#c71585 	199,21,133
+midnightblue 	#191970 	25,25,112
+mintcream 	#f5fffa 	245,255,250
+mistyrose 	#ffe4e1 	255,228,225
+moccasin 	#ffe4b5 	255,228,181
+navajowhite 	#ffdead 	255,222,173
+navy 	#000080 	0,0,128
+oldlace 	#fdf5e6 	253,245,230
+olive 	#808000 	128,128,0
+olivedrab 	#6b8e23 	107,142,35
+orange 	#ffa500 	255,165,0
+orangered 	#ff4500 	255,69,0
+orchid 	#da70d6 	218,112,214
+palegoldenrod 	#eee8aa 	238,232,170
+palegreen 	#98fb98 	152,251,152
+paleturquoise 	#afeeee 	175,238,238
+palevioletred 	#db7093 	219,112,147
+papayawhip 	#ffefd5 	255,239,213
+peachpuff 	#ffdab9 	255,218,185
+peru 	#cd853f 	205,133,63
+pink 	#ffc0cb 	255,192,203
+plum 	#dda0dd 	221,160,221
+powderblue 	#b0e0e6 	176,224,230
+purple 	#800080 	128,0,128
+red 	#ff0000 	255,0,0
+rosybrown 	#bc8f8f 	188,143,143
+royalblue 	#4169e1 	65,105,225
+saddlebrown 	#8b4513 	139,69,19
+salmon 	#fa8072 	250,128,114
+sandybrown 	#f4a460 	244,164,96
+seagreen 	#2e8b57 	46,139,87
+seashell 	#fff5ee 	255,245,238
+sienna 	#a0522d 	160,82,45
+silver 	#c0c0c0 	192,192,192
+skyblue 	#87ceeb 	135,206,235
+slateblue 	#6a5acd 	106,90,205
+slategray 	#708090 	112,128,144
+slategrey 	#708090 	112,128,144
+snow 	#fffafa 	255,250,250
+springgreen 	#00ff7f 	0,255,127
+steelblue 	#4682b4 	70,130,180
+tan 	#d2b48c 	210,180,140
+teal 	#008080 	0,128,128
+thistle 	#d8bfd8 	216,191,216
+tomato 	#ff6347 	255,99,71
+turquoise 	#40e0d0 	64,224,208
+violet 	#ee82ee 	238,130,238
+wheat 	#f5deb3 	245,222,179
+white 	#ffffff 	255,255,255
+whitesmoke 	#f5f5f5 	245,245,245
+yellow 	#ffff00 	255,255,0
+yellowgreen 	#9acd32 	154,205,50

drawing/color.go

@@ -2,28 +2,46 @@ package drawing
 
 import (
 	"fmt"
+	"regexp"
 	"strconv"
 	"strings"
 )
 
+// Basic Colors from:
+// https://www.w3.org/wiki/CSS/Properties/color/keywords
 var (
 	// ColorTransparent is a fully transparent color.
 	ColorTransparent = Color{R: 255, G: 255, B: 255, A: 0}
-
 	// 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}
+	ColorGreen = Color{R: 0, G: 128, B: 0, A: 255}
-
 	// ColorBlue is blue.
 	ColorBlue = Color{R: 0, G: 0, B: 255, A: 255}
+	// ColorSilver is a known color.
+	ColorSilver = Color{R: 192, G: 192, B: 192, A: 255}
+	// ColorMaroon is a known color.
+	ColorMaroon = Color{R: 128, G: 0, B: 0, A: 255}
+	// ColorPurple is a known color.
+	ColorPurple = Color{R: 128, G: 0, B: 128, A: 255}
+	// ColorFuchsia is a known color.
+	ColorFuchsia = Color{R: 255, G: 0, B: 255, A: 255}
+	// ColorLime is a known color.
+	ColorLime = Color{R: 0, G: 255, B: 0, A: 255}
+	// ColorOlive is a known color.
+	ColorOlive = Color{R: 128, G: 128, B: 0, A: 255}
+	// ColorYellow is a known color.
+	ColorYellow = Color{R: 255, G: 255, B: 0, A: 255}
+	// ColorNavy is a known color.
+	ColorNavy = Color{R: 0, G: 0, B: 128, A: 255}
+	// ColorTeal is a known color.
+	ColorTeal = Color{R: 0, G: 128, B: 128, A: 255}
+	// ColorAqua is a known color.
+	ColorAqua = Color{R: 0, G: 255, B: 255, A: 255}
 )
 
 func parseHex(hex string) uint8 {
@@ -31,6 +49,90 @@ func parseHex(hex string) uint8 {
 	return uint8(v)
 }
 
+// ParseColor parses a color from a string.
+func ParseColor(rawColor string) Color {
+	if strings.HasPrefix(rawColor, "rgba") {
+		return ColorFromRGBA(rawColor)
+	}
+	if strings.HasPrefix(rawColor, "rgb") {
+		return ColorFromRGB(rawColor)
+	}
+	if strings.HasPrefix(rawColor, "#") {
+		return ColorFromHex(rawColor)
+	}
+	return ColorFromKnown(rawColor)
+}
+
+var rgbaexpr = regexp.MustCompile(`rgba\((?P<R>.+),(?P<G>.+),(?P<B>.+),(?P<A>.+)\)`)
+
+// ColorFromRGBA returns a color from an `rgba()` css function.
+func ColorFromRGBA(rgba string) (output Color) {
+	values := rgbaexpr.FindStringSubmatch(rgba)
+	for i, name := range rgbaexpr.SubexpNames() {
+		if i == 0 {
+			continue
+		}
+		if i >= len(values) {
+			break
+		}
+		switch name {
+		case "R":
+			value := strings.TrimSpace(values[i])
+			parsed, _ := strconv.ParseInt(value, 10, 16)
+			output.R = uint8(parsed)
+		case "G":
+			value := strings.TrimSpace(values[i])
+			parsed, _ := strconv.ParseInt(value, 10, 16)
+			output.G = uint8(parsed)
+		case "B":
+			value := strings.TrimSpace(values[i])
+			parsed, _ := strconv.ParseInt(value, 10, 16)
+			output.B = uint8(parsed)
+		case "A":
+			value := strings.TrimSpace(values[i])
+			parsed, _ := strconv.ParseFloat(value, 32)
+			if parsed > 1 {
+				parsed = 1
+			} else if parsed < 0 {
+				parsed = 0
+			}
+			output.A = uint8(parsed * 255)
+		}
+	}
+	return
+}
+
+var rgbexpr = regexp.MustCompile(`rgb\((?P<R>.+),(?P<G>.+),(?P<B>.+)\)`)
+
+// ColorFromRGB returns a color from an `rgb()` css function.
+func ColorFromRGB(rgb string) (output Color) {
+	output.A = 255
+	values := rgbexpr.FindStringSubmatch(rgb)
+	for i, name := range rgbaexpr.SubexpNames() {
+		if i == 0 {
+			continue
+		}
+		if i >= len(values) {
+			break
+		}
+		switch name {
+		case "R":
+			value := strings.TrimSpace(values[i])
+			parsed, _ := strconv.ParseInt(value, 10, 16)
+			output.R = uint8(parsed)
+		case "G":
+			value := strings.TrimSpace(values[i])
+			parsed, _ := strconv.ParseInt(value, 10, 16)
+			output.G = uint8(parsed)
+		case "B":
+			value := strings.TrimSpace(values[i])
+			parsed, _ := strconv.ParseInt(value, 10, 16)
+			output.B = uint8(parsed)
+		}
+	}
+	return
+}
+
 // ColorFromHex returns a color from a css hex code.
 //
 // NOTE: it will trim a leading '#' character if present.
@@ -52,6 +154,43 @@ func ColorFromHex(hex string) Color {
 	return c
 }
 
+func ColorFromKnown(known string) Color {
+	switch strings.ToLower(known) {
+	case "white":
+		return ColorWhite
+	case "black":
+		return ColorBlack
+	case "red":
+		return ColorRed
+	case "blue":
+		return ColorBlue
+	case "green":
+		return ColorGreen
+	case "silver":
+		return ColorSilver
+	case "maroon":
+		return ColorMaroon
+	case "purple":
+		return ColorPurple
+	case "fuchsia":
+		return ColorFuchsia
+	case "lime":
+		return ColorLime
+	case "olive":
+		return ColorOlive
+	case "yellow":
+		return ColorYellow
+	case "navy":
+		return ColorNavy
+	case "teal":
+		return ColorTeal
+	case "aqua":
+		return ColorAqua
+	default:
+		return Color{}
+	}
+}
+
 // ColorFromAlphaMixedRGBA returns the system alpha mixed rgba values.
 func ColorFromAlphaMixedRGBA(r, g, b, a uint32) Color {
 	fa := float64(a) / 255.0

drawing/color_test.go

@@ -1,6 +1,7 @@
 package drawing
 
 import (
+	"fmt"
 	"testing"
 
 	"image/color"
@@ -27,11 +28,11 @@ func TestColorFromHex(t *testing.T) {
 	shortRed := ColorFromHex("F00")
 	testutil.AssertEqual(t, ColorRed, shortRed)
 
-	green := ColorFromHex("00FF00")
+	green := ColorFromHex("008000")
 	testutil.AssertEqual(t, ColorGreen, green)
 
-	shortGreen := ColorFromHex("0F0")
+	// shortGreen := ColorFromHex("0F0")
-	testutil.AssertEqual(t, ColorGreen, shortGreen)
+	// testutil.AssertEqual(t, ColorGreen, shortGreen)
 
 	blue := ColorFromHex("0000FF")
 	testutil.AssertEqual(t, ColorBlue, blue)
@@ -55,3 +56,59 @@ func TestColorFromAlphaMixedRGBA(t *testing.T) {
 	white := ColorFromAlphaMixedRGBA(color.White.RGBA())
 	testutil.AssertTrue(t, white.Equals(ColorWhite), white.String())
 }
+
+func Test_ColorFromRGBA(t *testing.T) {
+	value := "rgba(192, 192, 192, 1.0)"
+	parsed := ColorFromRGBA(value)
+	testutil.AssertEqual(t, ColorSilver, parsed)
+
+	value = "rgba(192,192,192,1.0)"
+	parsed = ColorFromRGBA(value)
+	testutil.AssertEqual(t, ColorSilver, parsed)
+
+	value = "rgba(192,192,192,1.5)"
+	parsed = ColorFromRGBA(value)
+	testutil.AssertEqual(t, ColorSilver, parsed)
+}
+
+func TestParseColor(t *testing.T) {
+	testCases := [...]struct {
+		Input    string
+		Expected Color
+	}{
+		{"", Color{}},
+		{"white", ColorWhite},
+		{"WHITE", ColorWhite}, // caps!
+		{"black", ColorBlack},
+		{"red", ColorRed},
+		{"green", ColorGreen},
+		{"blue", ColorBlue},
+		{"silver", ColorSilver},
+		{"maroon", ColorMaroon},
+		{"purple", ColorPurple},
+		{"fuchsia", ColorFuchsia},
+		{"lime", ColorLime},
+		{"olive", ColorOlive},
+		{"yellow", ColorYellow},
+		{"navy", ColorNavy},
+		{"teal", ColorTeal},
+		{"aqua", ColorAqua},
+
+		{"rgba(192, 192, 192, 1.0)", ColorSilver},
+		{"rgba(192,192,192,1.0)", ColorSilver},
+		{"rgb(192, 192, 192)", ColorSilver},
+		{"rgb(192,192,192)", ColorSilver},
+
+		{"#FF0000", ColorRed},
+		{"#008000", ColorGreen},
+		{"#0000FF", ColorBlue},
+		{"#F00", ColorRed},
+		{"#080", Color{0, 136, 0, 255}},
+		{"#00F", ColorBlue},
+	}
+
+	for index, tc := range testCases {
+		actual := ParseColor(tc.Input)
+		testutil.AssertEqual(t, tc.Expected, actual, fmt.Sprintf("test case: %d -> %s", index, tc.Input))
+	}
+}

testutil/helpers.go

@@ -9,6 +9,7 @@ import (
 
 // AssertNil asserts an argument is nil.
 func AssertNil(t *testing.T, actual interface{}) {
+	t.Helper()
 	if !isNil(actual) {
 		t.Errorf("assertion failed; expected actual to be nil")
 		t.FailNow()
@@ -17,6 +18,7 @@ func AssertNil(t *testing.T, actual interface{}) {
 
 // AssertNotNil asserts an argument is not nil.
 func AssertNotNil(t *testing.T, actual interface{}, message ...interface{}) {
+	t.Helper()
 	if isNil(actual) {
 		t.Error("assertion failed; expected actual to not be nil")
 		if len(message) > 0 {
@@ -28,6 +30,7 @@ func AssertNotNil(t *testing.T, actual interface{}, message ...interface{}) {
 
 // AssertEqual asserts two arguments are equal.
 func AssertEqual(t *testing.T, expected, actual interface{}, message ...interface{}) {
+	t.Helper()
 	if !equal(expected, actual) {
 		t.Errorf("assertion failed; expected %v to equal %v", actual, expected)
 		if len(message) > 0 {
@@ -39,6 +42,7 @@ func AssertEqual(t *testing.T, expected, actual interface{}, message ...interfac
 
 // AssertNotEqual asserts two arguments are not equal.
 func AssertNotEqual(t *testing.T, expected, actual interface{}, message ...interface{}) {
+	t.Helper()
 	if equal(expected, actual) {
 		t.Errorf("assertion failed; expected %v to not equal %v", actual, expected)
 		if len(message) > 0 {
@@ -50,16 +54,19 @@ func AssertNotEqual(t *testing.T, expected, actual interface{}, message ...inter
 
 // AssertZero asserts an argument is zero.
 func AssertZero(t *testing.T, actual interface{}, message ...interface{}) {
+	t.Helper()
 	AssertEqual(t, 0, actual)
 }
 
 // AssertNotZero asserts an argument is not zero.
 func AssertNotZero(t *testing.T, actual interface{}, message ...interface{}) {
+	t.Helper()
 	AssertNotEqual(t, 0, actual)
 }
 
 // AssertTrue asserts an argument is true.
 func AssertTrue(t *testing.T, arg bool, message ...interface{}) {
+	t.Helper()
 	if !arg {
 		t.Errorf("assertion failed; expected actual to be true")
 		if len(message) > 0 {
@@ -71,6 +78,7 @@ func AssertTrue(t *testing.T, arg bool, message ...interface{}) {
 
 // AssertFalse asserts an argument is false.
 func AssertFalse(t *testing.T, arg bool, message ...interface{}) {
+	t.Helper()
 	if arg {
 		t.Errorf("assertion failed; expected actual to be false")
 		if len(message) > 0 {
@@ -84,6 +92,7 @@ func AssertFalse(t *testing.T, arg bool, message ...interface{}) {
 //
 // This delta will be determined absolute, and the delta should always be positive.
 func AssertInDelta(t *testing.T, from, to, delta float64, message ...interface{}) {
+	t.Helper()
 	if diff := math.Abs(from - to); diff > delta {
 		t.Errorf("assertion failed; expected absolute difference of %f and %f to be %f", from, to, delta)
 		if len(message) > 0 {
@@ -95,6 +104,7 @@ func AssertInDelta(t *testing.T, from, to, delta float64, message ...interface{}
 
 // AssertEmpty asserts an argument is empty.
 func AssertEmpty(t *testing.T, arg interface{}, message ...interface{}) {
+	t.Helper()
 	if getLength(arg) != 0 {
 		t.Errorf("assertion failed; expected actual to be empty")
 		if len(message) > 0 {
@@ -106,6 +116,7 @@ func AssertEmpty(t *testing.T, arg interface{}, message ...interface{}) {
 
 // AssertNotEmpty asserts an argument is not empty.
 func AssertNotEmpty(t *testing.T, arg interface{}, message ...interface{}) {
+	t.Helper()
 	if getLength(arg) == 0 {
 		t.Errorf("assertion failed; expected actual to not be empty")
 		if len(message) > 0 {
@@ -117,6 +128,7 @@ func AssertNotEmpty(t *testing.T, arg interface{}, message ...interface{}) {
 
 // AssertLen asserts an argument has a given length.
 func AssertLen(t *testing.T, arg interface{}, length int, message ...interface{}) {
+	t.Helper()
 	if getLength(arg) != length {
 		t.Errorf("assertion failed; expected actual to have length %d", length)
 		if len(message) > 0 {
@@ -128,6 +140,7 @@ func AssertLen(t *testing.T, arg interface{}, length int, message ...interface{}
 
 // AssertContains asserts an argument contains a given substring.
 func AssertContains(t *testing.T, s, substr string, message ...interface{}) {
+	t.Helper()
 	if !strings.Contains(s, substr) {
 		t.Errorf("assertion failed; expected actual to contain %q", substr)
 		if len(message) > 0 {
@@ -139,6 +152,7 @@ func AssertContains(t *testing.T, s, substr string, message ...interface{}) {
 
 // AssertNotContains asserts an argument does not contain a given substring.
 func AssertNotContains(t *testing.T, s, substr string, message ...interface{}) {
+	t.Helper()
 	if strings.Contains(s, substr) {
 		t.Errorf("assertion failed; expected actual to not contain %q", substr)
 		if len(message) > 0 {