add FillString method on Graphic context

draw2d/src/cmd/testdraw2d.go

@@ -494,6 +494,19 @@ func TestPathTransform() {
 	saveToPngFile("TestPathTransform", i)
 }
 
+func TestFillString() {
+	i, gc := initGc(100, 100)   
+	draw2d.RoundRect(gc, 5, 5, 95, 95, 10, 10)
+	gc.FillStroke()
+	gc.SetFontSize(18)
+	gc.MoveTo(10, 52)
+	width := gc.FillString("cou")
+	fmt.Printf("width: %f\n", width)
+	gc.RMoveTo(width+1, 0)
+	gc.FillString("cou")
+	saveToPngFile("TestFillString", i)
+}
+
 func main() {
 	TestPath()
 	TestDrawArc()
@@ -511,4 +524,5 @@ func main() {
 	TestStar()
 	TestTransform()
 	TestPathTransform()
+	TestFillString()
 }

draw2d/src/pkg/draw2d/advanced_path.go

@@ -6,6 +6,8 @@ import (
 
 
 //high level path creation
+
+
 func Rect(path Path, x1, y1, x2, y2 float) {
 	path.MoveTo(x1, y1)
 	path.LineTo(x2, y1)

draw2d/src/pkg/draw2d/draw2d.go

@@ -6,9 +6,33 @@ package draw2d
 import (
 	"exp/draw"
 	"image"
+	"log"
+	"io/ioutil"
+	"freetype-go.googlecode.com/hg/freetype"
 	"freetype-go.googlecode.com/hg/freetype/raster"
+	"freetype-go.googlecode.com/hg/freetype/truetype"
 )
 
+var (
+	font *truetype.Font
+)
+
+func init() {
+	// Read the font data.
+	
+	fontBytes, err := ioutil.ReadFile("../../luxi-fonts/luxisr.ttf")
+	if err != nil {
+		log.Println(err)
+		return
+	}
+	font, err = freetype.ParseFont(fontBytes)
+	if err != nil {
+		log.Println(err)
+		return
+	}
+}
+
+
 type FillRule int
 
 const (
@@ -20,6 +44,8 @@ type GraphicContext struct {
 	PaintedImage     *image.RGBA
 	fillRasterizer   *raster.Rasterizer
 	strokeRasterizer *raster.Rasterizer
+	freetype    	 *freetype.Context
+	DPI			     int
 	current          *contextStack
 }
 
@@ -35,6 +61,7 @@ type contextStack struct {
 	cap         Cap
 	join        Join
 	previous    *contextStack
+	fontSize    float
 }
 
 /**
@@ -46,7 +73,14 @@ func NewGraphicContext(pi *image.RGBA) *GraphicContext {
 	width, height := gc.PaintedImage.Bounds().Dx(), gc.PaintedImage.Bounds().Dy()
 	gc.fillRasterizer = raster.NewRasterizer(width, height)
 	gc.strokeRasterizer = raster.NewRasterizer(width, height)
-
+	
+	gc.DPI = 92
+	gc.freetype = freetype.NewContext()
+	gc.freetype.SetDPI(gc.DPI)
+	gc.freetype.SetFont(font)
+	gc.freetype.SetClip(pi.Bounds())
+	gc.freetype.SetDst(pi)
+	
 	gc.current = new(contextStack)
 
 	gc.current.tr = NewIdentityMatrix()
@@ -57,6 +91,8 @@ func NewGraphicContext(pi *image.RGBA) *GraphicContext {
 	gc.current.cap = RoundCap
 	gc.current.fillRule = FillRuleEvenOdd
 	gc.current.join = RoundJoin
+	gc.current.fontSize = 10
+	
 	return gc
 }
 
@@ -119,8 +155,27 @@ func (gc *GraphicContext) SetLineDash(dash []float, dashOffset float) {
 	gc.current.dashOffset = dashOffset
 }
 
+func (gc *GraphicContext) SetFontSize(fontSize float) {
+	gc.current.fontSize = fontSize
+}
+
+func (gc *GraphicContext) GetFontSize() float {
+	return gc.current.fontSize
+}
+
+func (gc *GraphicContext) SetDPI(dpi int) {
+	gc.DPI = dpi
+	gc.freetype.SetDPI(dpi)
+}
+
+func (gc *GraphicContext) GetDPI() int {
+	return gc.DPI
+}
+
+
 func (gc *GraphicContext) Save() {
 	context := new(contextStack)
+	context.fontSize = gc.current.fontSize
 	context.lineWidth = gc.current.lineWidth
 	context.strokeColor = gc.current.strokeColor
 	context.fillColor = gc.current.fillColor
@@ -191,6 +246,30 @@ func (gc *GraphicContext) Close() {
 	gc.current.path.Close()
 }
 
+func (gc *GraphicContext) FillString(text string) (cursor float){
+	gc.freetype.SetSrc(image.NewColorImage(gc.current.strokeColor))
+	// Draw the text.
+	x, y := gc.current.path.LastPoint()
+	gc.current.tr.Transform(&x, &y)
+	x0, fontSize := 0.0, gc.current.fontSize
+	gc.current.tr.VectorTransform(&x0, &fontSize)
+	gc.freetype.SetFontSize(fontSize)
+	pt := freetype.Pt(int(x), int(y))
+	p, err := gc.freetype.DrawString(text, pt)
+	if err != nil {
+		log.Println(err)
+	}
+	x1, _ := gc.current.path.LastPoint()
+	x2, y2 := float(p.X) / 256, float(p.Y) / 256
+	log.Printf("x2: %f, y2: %f\n", x2, y2)
+	gc.current.tr.InverseTransform(&x2, &y2)
+	log.Printf("x2: %f, y2: %f\n", x2, y2)
+	width := x2 - x1
+	return width 
+}
+
+
+
 func (gc *GraphicContext) paint(rasterizer *raster.Rasterizer, color image.Color) {
 	painter := raster.NewRGBAPainter(gc.PaintedImage)
 	painter.SetColor(color)