slightly more rigorous bounds checking and auto-fit

testserver/main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"bytes"
 	"fmt"
 	"log"
 	"math/rand"
@@ -8,6 +9,7 @@ import (
 	"time"
 
 	"github.com/wcharczuk/go-chart"
+	"github.com/wcharczuk/go-chart/drawing"
 	"github.com/wcharczuk/go-web"
 )
 
@@ -36,7 +38,7 @@ func chartHandler(rc *web.RequestContext) web.ControllerResult {
 	c := chart.Chart{
 		Title: "A Test Chart",
 		TitleStyle: chart.Style{
-			Show: true,
+			Show: false,
 		},
 		Width:  1024,
 		Height: 400,
@@ -91,6 +93,104 @@ func chartHandler(rc *web.RequestContext) web.ControllerResult {
 	return nil
 }
 
+func boxHandler(rc *web.RequestContext) web.ControllerResult {
+	r, err := chart.PNG(1024, 1024)
+	if err != nil {
+		rc.API().InternalError(err)
+	}
+
+	f, err := chart.GetDefaultFont()
+	if err != nil {
+		return rc.API().InternalError(err)
+	}
+
+	//1:1 128wx128h @ 64,64
+	a := chart.Box{Top: 64, Left: 64, Right: 192, Bottom: 192}
+
+	// 3:2 256x170 @ 16, 16
+	//b := chart.Box{Top: 16, Left: 16, Right: 256, Bottom: 170}
+
+	// 2:3 170x256 @ 16, 16
+	c := chart.Box{Top: 16, Left: 16, Right: 170, Bottom: 256}
+
+	//fitb := a.Fit(b)
+	fitc := a.Fit(c)
+	//growb := a.Grow(b)
+	//growc := a.Grow(c)
+	//grow := a.Grow(b).Grow(c)
+
+	conc := a.Constrain(c)
+
+	boxStyle := chart.Style{
+		StrokeColor: drawing.ColorBlack,
+		StrokeWidth: 1.0,
+		Font:        f,
+		FontSize:    18.0,
+	}
+
+	computedBoxStyle := chart.Style{
+		StrokeColor: drawing.ColorRed,
+		StrokeWidth: 1.0,
+		Font:        f,
+		FontSize:    18.0,
+	}
+
+	chart.DrawBox(r, a, boxStyle)
+	//chart.DrawBox(r, b, boxStyle)
+	chart.DrawBox(r, c, boxStyle)
+	//chart.DrawBox(r, fitb, computedBoxStyle)
+	chart.DrawBox(r, fitc, computedBoxStyle)
+	/*chart.DrawBox(r, growb, computedBoxStyle)
+	chart.DrawBox(r, growc, computedBoxStyle)
+	chart.DrawBox(r, grow, computedBoxStyle)*/
+	chart.DrawBox(r, conc, computedBoxStyle)
+
+	ax, ay := a.Center()
+	chart.DrawTextCentered(r, "a", ax, ay, boxStyle.WithDefaultsFrom(chart.Style{
+		FillColor: boxStyle.StrokeColor,
+	}))
+
+	/*bx, by := b.Center()
+	chart.DrawTextCentered(r, "b", bx, by, boxStyle.WithDefaultsFrom(chart.Style{
+		FillColor: boxStyle.StrokeColor,
+	}))*/
+
+	cx, cy := c.Center()
+	chart.DrawTextCentered(r, "c", cx, cy, boxStyle.WithDefaultsFrom(chart.Style{
+		FillColor: boxStyle.StrokeColor,
+	}))
+
+	/*fbx, fby := fitb.Center()
+	chart.DrawTextCentered(r, "a fit b", fbx, fby, computedBoxStyle.WithDefaultsFrom(chart.Style{
+		FillColor: computedBoxStyle.StrokeColor,
+	}))*/
+
+	fcx, fcy := fitc.Center()
+	chart.DrawTextCentered(r, "a fit c", fcx, fcy, computedBoxStyle.WithDefaultsFrom(chart.Style{
+		FillColor: computedBoxStyle.StrokeColor,
+	}))
+
+	/*gbx, gby := growb.Center()
+	chart.DrawTextCentered(r, "a grow b", gbx, gby, computedBoxStyle.WithDefaultsFrom(chart.Style{
+		FillColor: computedBoxStyle.StrokeColor,
+	}))
+
+	gcx, gcy := growc.Center()
+	chart.DrawTextCentered(r, "a grow c", gcx, gcy, computedBoxStyle.WithDefaultsFrom(chart.Style{
+		FillColor: computedBoxStyle.StrokeColor,
+	}))*/
+
+	ccx, ccy := conc.Center()
+	chart.DrawTextCentered(r, "a const c", ccx, ccy, computedBoxStyle.WithDefaultsFrom(chart.Style{
+		FillColor: computedBoxStyle.StrokeColor,
+	}))
+
+	rc.Response.Header().Set("Content-Type", "image/png")
+	buffer := bytes.NewBuffer([]byte{})
+	err = r.Save(buffer)
+	return rc.Raw(buffer.Bytes())
+}
+
 func main() {
 	app := web.New()
 	app.SetName("Chart Test Server")
@@ -100,5 +200,6 @@ func main() {
 	app.GET("/favico.ico", func(rc *web.RequestContext) web.ControllerResult {
 		return rc.Raw([]byte{})
 	})
+	app.GET("/box", boxHandler)
 	log.Fatal(app.Start())
 }