1 files changed, 359 insertions, 0 deletions
diff --git a/Godeps/_workspace/src/code.google.com/p/draw2d/draw2d/image.go b/Godeps/_workspace/src/code.google.com/p/draw2d/draw2d/image.go
new file mode 100644
index 000000000..9f91bc71f
--- /dev/null
+++ b/Godeps/_workspace/src/code.google.com/p/draw2d/draw2d/image.go
@@ -0,0 +1,359 @@
+// Copyright 2010 The draw2d Authors. All rights reserved.
+// created: 21/11/2010 by Laurent Le Goff
+
+package draw2d
+
+import (
+	"code.google.com/p/freetype-go/freetype/raster"
+	"code.google.com/p/freetype-go/freetype/truetype"
+	"errors"
+	"image"
+	"image/color"
+	"image/draw"
+	"log"
+	"math"
+)
+
+type Painter interface {
+	raster.Painter
+	SetColor(color color.Color)
+}
+
+var (
+	defaultFontData = FontData{"luxi", FontFamilySans, FontStyleNormal}
+)
+
+type ImageGraphicContext struct {
+	*StackGraphicContext
+	img              draw.Image
+	painter          Painter
+	fillRasterizer   *raster.Rasterizer
+	strokeRasterizer *raster.Rasterizer
+	glyphBuf         *truetype.GlyphBuf
+	DPI              int
+}
+
+/**
+ * Create a new Graphic context from an image
+ */
+func NewGraphicContext(img draw.Image) *ImageGraphicContext {
+	var painter Painter
+	switch selectImage := img.(type) {
+	case *image.RGBA:
+		painter = raster.NewRGBAPainter(selectImage)
+	default:
+		panic("Image type not supported")
+	}
+	return NewGraphicContextWithPainter(img, painter)
+}
+
+// Create a new Graphic context from an image and a Painter (see Freetype-go)
+func NewGraphicContextWithPainter(img draw.Image, painter Painter) *ImageGraphicContext {
+	width, height := img.Bounds().Dx(), img.Bounds().Dy()
+	dpi := 92
+	gc := &ImageGraphicContext{
+		NewStackGraphicContext(),
+		img,
+		painter,
+		raster.NewRasterizer(width, height),
+		raster.NewRasterizer(width, height),
+		truetype.NewGlyphBuf(),
+		dpi,
+	}
+	return gc
+}
+
+func (gc *ImageGraphicContext) GetDPI() int {
+	return gc.DPI
+}
+
+func (gc *ImageGraphicContext) Clear() {
+	width, height := gc.img.Bounds().Dx(), gc.img.Bounds().Dy()
+	gc.ClearRect(0, 0, width, height)
+}
+
+func (gc *ImageGraphicContext) ClearRect(x1, y1, x2, y2 int) {
+	imageColor := image.NewUniform(gc.Current.FillColor)
+	draw.Draw(gc.img, image.Rect(x1, y1, x2, y2), imageColor, image.ZP, draw.Over)
+}
+
+func (gc *ImageGraphicContext) DrawImage(img image.Image) {
+	DrawImage(img, gc.img, gc.Current.Tr, draw.Over, BilinearFilter)
+}
+
+func (gc *ImageGraphicContext) FillString(text string) (cursor float64) {
+	return gc.FillStringAt(text, 0, 0)
+}
+
+func (gc *ImageGraphicContext) FillStringAt(text string, x, y float64) (cursor float64) {
+	width := gc.CreateStringPath(text, x, y)
+	gc.Fill()
+	return width
+}
+
+func (gc *ImageGraphicContext) StrokeString(text string) (cursor float64) {
+	return gc.StrokeStringAt(text, 0, 0)
+}
+
+func (gc *ImageGraphicContext) StrokeStringAt(text string, x, y float64) (cursor float64) {
+	width := gc.CreateStringPath(text, x, y)
+	gc.Stroke()
+	return width
+}
+
+func (gc *ImageGraphicContext) loadCurrentFont() (*truetype.Font, error) {
+	font := GetFont(gc.Current.FontData)
+	if font == nil {
+		font = GetFont(defaultFontData)
+	}
+	if font == nil {
+		return nil, errors.New("No font set, and no default font available.")
+	}
+	gc.SetFont(font)
+	gc.SetFontSize(gc.Current.FontSize)
+	return font, nil
+}
+
+func fUnitsToFloat64(x int32) float64 {
+	scaled := x << 2
+	return float64(scaled/256) + float64(scaled%256)/256.0
+}
+
+// p is a truetype.Point measured in FUnits and positive Y going upwards.
+// The returned value is the same thing measured in floating point and positive Y
+// going downwards.
+func pointToF64Point(p truetype.Point) (x, y float64) {
+	return fUnitsToFloat64(p.X), -fUnitsToFloat64(p.Y)
+}
+
+// drawContour draws the given closed contour at the given sub-pixel offset.
+func (gc *ImageGraphicContext) drawContour(ps []truetype.Point, dx, dy float64) {
+	if len(ps) == 0 {
+		return
+	}
+	startX, startY := pointToF64Point(ps[0])
+	gc.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 {
+				gc.LineTo(qX+dx, qY+dy)
+			} else {
+				gc.QuadCurveTo(q0X+dx, q0Y+dy, qX+dx, qY+dy)
+			}
+		} else {
+			if on0 {
+				// No-op.
+			} else {
+				midX := (q0X + qX) / 2
+				midY := (q0Y + qY) / 2
+				gc.QuadCurveTo(q0X+dx, q0Y+dy, midX+dx, midY+dy)
+			}
+		}
+		q0X, q0Y, on0 = qX, qY, on
+	}
+	// Close the curve.
+	if on0 {
+		gc.LineTo(startX+dx, startY+dy)
+	} else {
+		gc.QuadCurveTo(q0X+dx, q0Y+dy, startX+dx, startY+dy)
+	}
+}
+
+func (gc *ImageGraphicContext) drawGlyph(glyph truetype.Index, dx, dy float64) error {
+	if err := gc.glyphBuf.Load(gc.Current.font, gc.Current.scale, glyph, truetype.NoHinting); err != nil {
+		return err
+	}
+	e0 := 0
+	for _, e1 := range gc.glyphBuf.End {
+		gc.drawContour(gc.glyphBuf.Point[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 (gc *ImageGraphicContext) CreateStringPath(s string, x, y float64) float64 {
+	font, err := gc.loadCurrentFont()
+	if err != nil {
+		log.Println(err)
+		return 0.0
+	}
+	startx := x
+	prev, hasPrev := truetype.Index(0), false
+	for _, rune := range s {
+		index := font.Index(rune)
+		if hasPrev {
+			x += fUnitsToFloat64(font.Kerning(gc.Current.scale, prev, index))
+		}
+		err := gc.drawGlyph(index, x, y)
+		if err != nil {
+			log.Println(err)
+			return startx - x
+		}
+		x += fUnitsToFloat64(font.HMetric(gc.Current.scale, index).AdvanceWidth)
+		prev, hasPrev = index, true
+	}
+	return x - startx
+}
+
+// GetStringBounds returns the approximate pixel bounds of the string s at x, y.
+// The the left edge of the em square of the first character of s
+// and the baseline intersect at 0, 0 in the returned coordinates.
+// Therefore the top and left coordinates may well be negative.
+func (gc *ImageGraphicContext) GetStringBounds(s string) (left, top, right, bottom float64) {
+	font, err := gc.loadCurrentFont()
+	if err != nil {
+		log.Println(err)
+		return 0, 0, 0, 0
+	}
+	top, left, bottom, right = 10e6, 10e6, -10e6, -10e6
+	cursor := 0.0
+	prev, hasPrev := truetype.Index(0), false
+	for _, rune := range s {
+		index := font.Index(rune)
+		if hasPrev {
+			cursor += fUnitsToFloat64(font.Kerning(gc.Current.scale, prev, index))
+		}
+		if err := gc.glyphBuf.Load(gc.Current.font, gc.Current.scale, index, truetype.NoHinting); err != nil {
+			log.Println(err)
+			return 0, 0, 0, 0
+		}
+		e0 := 0
+		for _, e1 := range gc.glyphBuf.End {
+			ps := gc.glyphBuf.Point[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)
+			}
+		}
+		cursor += fUnitsToFloat64(font.HMetric(gc.Current.scale, index).AdvanceWidth)
+		prev, hasPrev = index, true
+	}
+	return left, top, right, bottom
+}
+
+// recalc recalculates scale and bounds values from the font size, screen
+// resolution and font metrics, and invalidates the glyph cache.
+func (gc *ImageGraphicContext) recalc() {
+	gc.Current.scale = int32(gc.Current.FontSize * float64(gc.DPI) * (64.0 / 72.0))
+}
+
+// SetDPI sets the screen resolution in dots per inch.
+func (gc *ImageGraphicContext) SetDPI(dpi int) {
+	gc.DPI = dpi
+	gc.recalc()
+}
+
+// SetFont sets the font used to draw text.
+func (gc *ImageGraphicContext) SetFont(font *truetype.Font) {
+	gc.Current.font = font
+}
+
+// SetFontSize sets the font size in points (as in ``a 12 point font'').
+func (gc *ImageGraphicContext) SetFontSize(fontSize float64) {
+	gc.Current.FontSize = fontSize
+	gc.recalc()
+}
+
+func (gc *ImageGraphicContext) paint(rasterizer *raster.Rasterizer, color color.Color) {
+	gc.painter.SetColor(color)
+	rasterizer.Rasterize(gc.painter)
+	rasterizer.Clear()
+	gc.Current.Path.Clear()
+}
+
+/**** second method ****/
+func (gc *ImageGraphicContext) Stroke(paths ...*PathStorage) {
+	paths = append(paths, gc.Current.Path)
+	gc.strokeRasterizer.UseNonZeroWinding = true
+
+	stroker := NewLineStroker(gc.Current.Cap, gc.Current.Join, NewVertexMatrixTransform(gc.Current.Tr, NewVertexAdder(gc.strokeRasterizer)))
+	stroker.HalfLineWidth = gc.Current.LineWidth / 2
+	var pathConverter *PathConverter
+	if gc.Current.Dash != nil && len(gc.Current.Dash) > 0 {
+		dasher := NewDashConverter(gc.Current.Dash, gc.Current.DashOffset, stroker)
+		pathConverter = NewPathConverter(dasher)
+	} else {
+		pathConverter = NewPathConverter(stroker)
+	}
+	pathConverter.ApproximationScale = gc.Current.Tr.GetScale()
+	pathConverter.Convert(paths...)
+
+	gc.paint(gc.strokeRasterizer, gc.Current.StrokeColor)
+}
+
+/**** second method ****/
+func (gc *ImageGraphicContext) Fill(paths ...*PathStorage) {
+	paths = append(paths, gc.Current.Path)
+	gc.fillRasterizer.UseNonZeroWinding = gc.Current.FillRule.UseNonZeroWinding()
+
+	/**** first method ****/
+	pathConverter := NewPathConverter(NewVertexMatrixTransform(gc.Current.Tr, NewVertexAdder(gc.fillRasterizer)))
+	pathConverter.ApproximationScale = gc.Current.Tr.GetScale()
+	pathConverter.Convert(paths...)
+
+	gc.paint(gc.fillRasterizer, gc.Current.FillColor)
+}
+
+/* second method */
+func (gc *ImageGraphicContext) FillStroke(paths ...*PathStorage) {
+	gc.fillRasterizer.UseNonZeroWinding = gc.Current.FillRule.UseNonZeroWinding()
+	gc.strokeRasterizer.UseNonZeroWinding = true
+
+	filler := NewVertexMatrixTransform(gc.Current.Tr, NewVertexAdder(gc.fillRasterizer))
+
+	stroker := NewLineStroker(gc.Current.Cap, gc.Current.Join, NewVertexMatrixTransform(gc.Current.Tr, NewVertexAdder(gc.strokeRasterizer)))
+	stroker.HalfLineWidth = gc.Current.LineWidth / 2
+
+	demux := NewDemuxConverter(filler, stroker)
+	paths = append(paths, gc.Current.Path)
+	pathConverter := NewPathConverter(demux)
+	pathConverter.ApproximationScale = gc.Current.Tr.GetScale()
+	pathConverter.Convert(paths...)
+
+	gc.paint(gc.fillRasterizer, gc.Current.FillColor)
+	gc.paint(gc.strokeRasterizer, gc.Current.StrokeColor)
+}
+
+func (f FillRule) UseNonZeroWinding() bool {
+	switch f {
+	case FillRuleEvenOdd:
+		return false
+	case FillRuleWinding:
+		return true
+	}
+	return false
+}
+
+func (c Cap) Convert() raster.Capper {
+	switch c {
+	case RoundCap:
+		return raster.RoundCapper
+	case ButtCap:
+		return raster.ButtCapper
+	case SquareCap:
+		return raster.SquareCapper
+	}
+	return raster.RoundCapper
+}
+
+func (j Join) Convert() raster.Joiner {
+	switch j {
+	case RoundJoin:
+		return raster.RoundJoiner
+	case BevelJoin:
+		return raster.BevelJoiner
+	}
+	return raster.RoundJoiner
+}