1 files changed, 185 insertions, 0 deletions
diff --git a/vendor/github.com/golang/freetype/example/raster/main.go b/vendor/github.com/golang/freetype/example/raster/main.go
new file mode 100644
index 000000000..3e572e1c5
--- /dev/null
+++ b/vendor/github.com/golang/freetype/example/raster/main.go
@@ -0,0 +1,185 @@
+// Copyright 2010 The Freetype-Go Authors. All rights reserved.
+// Use of this source code is governed by your choice of either the
+// FreeType License or the GNU General Public License version 2 (or
+// any later version), both of which can be found in the LICENSE file.
+
+// +build example
+//
+// This build tag means that "go install github.com/golang/freetype/..."
+// doesn't install this example program. Use "go run main.go" to run it or "go
+// install -tags=example" to install it.
+
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"image"
+	"image/color"
+	"image/draw"
+	"image/png"
+	"log"
+	"os"
+
+	"github.com/golang/freetype/raster"
+	"golang.org/x/image/math/fixed"
+)
+
+type node struct {
+	x, y, degree int
+}
+
+// These contours "outside" and "inside" are from the 'A' glyph from the Droid
+// Serif Regular font.
+
+var outside = []node{
+	node{414, 489, 1},
+	node{336, 274, 2},
+	node{327, 250, 0},
+	node{322, 226, 2},
+	node{317, 203, 0},
+	node{317, 186, 2},
+	node{317, 134, 0},
+	node{350, 110, 2},
+	node{384, 86, 0},
+	node{453, 86, 1},
+	node{500, 86, 1},
+	node{500, 0, 1},
+	node{0, 0, 1},
+	node{0, 86, 1},
+	node{39, 86, 2},
+	node{69, 86, 0},
+	node{90, 92, 2},
+	node{111, 99, 0},
+	node{128, 117, 2},
+	node{145, 135, 0},
+	node{160, 166, 2},
+	node{176, 197, 0},
+	node{195, 246, 1},
+	node{649, 1462, 1},
+	node{809, 1462, 1},
+	node{1272, 195, 2},
+	node{1284, 163, 0},
+	node{1296, 142, 2},
+	node{1309, 121, 0},
+	node{1326, 108, 2},
+	node{1343, 96, 0},
+	node{1365, 91, 2},
+	node{1387, 86, 0},
+	node{1417, 86, 1},
+	node{1444, 86, 1},
+	node{1444, 0, 1},
+	node{881, 0, 1},
+	node{881, 86, 1},
+	node{928, 86, 2},
+	node{1051, 86, 0},
+	node{1051, 184, 2},
+	node{1051, 201, 0},
+	node{1046, 219, 2},
+	node{1042, 237, 0},
+	node{1034, 260, 1},
+	node{952, 489, 1},
+	node{414, 489, -1},
+}
+
+var inside = []node{
+	node{686, 1274, 1},
+	node{453, 592, 1},
+	node{915, 592, 1},
+	node{686, 1274, -1},
+}
+
+func p(n node) fixed.Point26_6 {
+	x, y := 20+n.x/4, 380-n.y/4
+	return fixed.Point26_6{
+		X: fixed.Int26_6(x << 6),
+		Y: fixed.Int26_6(y << 6),
+	}
+}
+
+func contour(r *raster.Rasterizer, ns []node) {
+	if len(ns) == 0 {
+		return
+	}
+	i := 0
+	r.Start(p(ns[i]))
+	for {
+		switch ns[i].degree {
+		case -1:
+			// -1 signifies end-of-contour.
+			return
+		case 1:
+			i += 1
+			r.Add1(p(ns[i]))
+		case 2:
+			i += 2
+			r.Add2(p(ns[i-1]), p(ns[i]))
+		default:
+			panic("bad degree")
+		}
+	}
+}
+
+func showNodes(m *image.RGBA, ns []node) {
+	for _, n := range ns {
+		p := p(n)
+		x, y := int(p.X)/64, int(p.Y)/64
+		if !(image.Point{x, y}).In(m.Bounds()) {
+			continue
+		}
+		var c color.Color
+		switch n.degree {
+		case 0:
+			c = color.RGBA{0, 255, 255, 255}
+		case 1:
+			c = color.RGBA{255, 0, 0, 255}
+		case 2:
+			c = color.RGBA{255, 0, 0, 255}
+		}
+		if c != nil {
+			m.Set(x, y, c)
+		}
+	}
+}
+
+func main() {
+	// Rasterize the contours to a mask image.
+	const (
+		w = 400
+		h = 400
+	)
+	r := raster.NewRasterizer(w, h)
+	contour(r, outside)
+	contour(r, inside)
+	mask := image.NewAlpha(image.Rect(0, 0, w, h))
+	p := raster.NewAlphaSrcPainter(mask)
+	r.Rasterize(p)
+
+	// Draw the mask image (in gray) onto an RGBA image.
+	rgba := image.NewRGBA(image.Rect(0, 0, w, h))
+	gray := image.NewUniform(color.Alpha{0x1f})
+	draw.Draw(rgba, rgba.Bounds(), image.Black, image.ZP, draw.Src)
+	draw.DrawMask(rgba, rgba.Bounds(), gray, image.ZP, mask, image.ZP, draw.Over)
+	showNodes(rgba, outside)
+	showNodes(rgba, inside)
+
+	// Save that RGBA image to disk.
+	outFile, err := os.Create("out.png")
+	if err != nil {
+		log.Println(err)
+		os.Exit(1)
+	}
+	defer outFile.Close()
+	b := bufio.NewWriter(outFile)
+	err = png.Encode(b, rgba)
+	if err != nil {
+		log.Println(err)
+		os.Exit(1)
+	}
+	err = b.Flush()
+	if err != nil {
+		log.Println(err)
+		os.Exit(1)
+	}
+	fmt.Println("Wrote out.png OK.")
+}