// NewGraphicContext creates a new Graphic context from an image.
func NewGraphicContext(width, height int) *GraphicContext {
gc := &GraphicContext{
draw2dbase.NewStackGraphicContext(),
NewPainter(),
raster.NewRasterizer(width, height),
raster.NewRasterizer(width, height),
}
return gc
}
// NewGraphicContextWithPainter creates a new Graphic context from an image and a Painter (see Freetype-go)
func NewGraphicContextWithPainter(img draw.Image, painter Painter) *GraphicContext {
width, height := img.Bounds().Dx(), img.Bounds().Dy()
dpi := 92
gc := &GraphicContext{
draw2dbase.NewStackGraphicContext(),
img,
painter,
raster.NewRasterizer(width, height),
raster.NewRasterizer(width, height),
truetype.NewGlyphBuf(),
dpi,
}
return gc
}
func BenchmarkFreetypeNonZeroWinding(b *testing.B) {
var p Path
p.LineTo(10, 190)
draw2dbase.TraceCubic(&p, []float64{10, 190, 10, 10, 190, 10, 190, 190}, 0.5)
poly := Polygon(p.points)
color := color.RGBA{0, 0, 0, 0xff}
for i := 0; i < b.N; i++ {
img := image.NewRGBA(image.Rect(0, 0, 200, 200))
rasterizer := raster.NewRasterizer(200, 200)
rasterizer.UseNonZeroWinding = true
rasterizer.Start(raster.Point{
X: raster.Fix32(10 * 256),
Y: raster.Fix32(190 * 256)})
for j := 0; j < len(poly); j = j + 2 {
rasterizer.Add1(raster.Point{
X: raster.Fix32(poly[j] * 256),
Y: raster.Fix32(poly[j+1] * 256)})
}
painter := raster.NewRGBAPainter(img)
painter.SetColor(color)
rasterizer.Rasterize(painter)
}
}
// NewContext creates a new Context.
func NewContext() *Context {
return &Context{
r: raster.NewRasterizer(0, 0),
fontSize: 12,
dpi: 72,
scale: 12 << 6,
}
}
func main() {
const (
w = 400
h = 400
)
r := raster.NewRasterizer(w, h)
r.UseNonZeroWinding = true
cjs := []struct {
c raster.Capper
j raster.Joiner
}{
{raster.RoundCapper, raster.RoundJoiner},
{raster.ButtCapper, raster.BevelJoiner},
{raster.SquareCapper, raster.BevelJoiner},
}
for i, cj := range cjs {
var path raster.Path
path.Start(fixed.P(30+100*i, 30+120*i))
path.Add1(fixed.P(180+100*i, 80+120*i))
path.Add1(fixed.P(50+100*i, 130+120*i))
raster.Stroke(r, path, fixed.I(20), cj.c, cj.j)
}
rgba := image.NewRGBA(image.Rect(0, 0, w, h))
draw.Draw(rgba, rgba.Bounds(), image.Black, image.Point{}, draw.Src)
p := raster.NewRGBAPainter(rgba)
p.SetColor(color.RGBA{0x7f, 0x7f, 0x7f, 0xff})
r.Rasterize(p)
white := color.RGBA{0xff, 0xff, 0xff, 0xff}
for i := range cjs {
rgba.SetRGBA(30+100*i, 30+120*i, white)
rgba.SetRGBA(180+100*i, 80+120*i, white)
rgba.SetRGBA(50+100*i, 130+120*i, white)
}
// 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.")
}
// NewContext creates a new Context.
func NewContext() *Context {
return &Context{
r: raster.NewRasterizer(0, 0),
glyphBuf: truetype.NewGlyphBuf(),
fontSize: 12,
dpi: 108,
scale: 12 << 6,
}
}
func main() {
// Draw a rounded corner that is one pixel wide.
r := raster.NewRasterizer(50, 50)
r.Start(p(5, 5))
r.Add1(p(5, 25))
r.Add2(p(5, 45), p(25, 45))
r.Add1(p(45, 45))
r.Add1(p(45, 44))
r.Add1(p(26, 44))
r.Add2(p(6, 44), p(6, 24))
r.Add1(p(6, 5))
r.Add1(p(5, 5))
// Rasterize that curve multiple times at different gammas.
const (
w = 600
h = 200
)
rgba := image.NewRGBA(image.Rect(0, 0, w, h))
draw.Draw(rgba, image.Rect(0, 0, w, h/2), image.Black, image.ZP, draw.Src)
draw.Draw(rgba, image.Rect(0, h/2, w, h), image.White, image.ZP, draw.Src)
mask := image.NewAlpha(image.Rect(0, 0, 50, 50))
painter := raster.NewAlphaSrcPainter(mask)
gammas := []float64{1.0 / 10.0, 1.0 / 3.0, 1.0 / 2.0, 2.0 / 3.0, 4.0 / 5.0, 1.0, 5.0 / 4.0, 3.0 / 2.0, 2.0, 3.0, 10.0}
for i, g := range gammas {
draw.Draw(mask, mask.Bounds(), image.Transparent, image.ZP, draw.Src)
r.Rasterize(raster.NewGammaCorrectionPainter(painter, g))
x, y := 50*i+25, 25
draw.DrawMask(rgba, image.Rect(x, y, x+50, y+50), image.White, image.ZP, mask, image.ZP, draw.Over)
y += 100
draw.DrawMask(rgba, image.Rect(x, y, x+50, y+50), image.Black, image.ZP, mask, image.ZP, draw.Over)
}
// Save that RGBA image to disk.
f, err := os.Create("out.png")
if err != nil {
log.Println(err)
os.Exit(1)
}
defer f.Close()
b := bufio.NewWriter(f)
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.")
}
func createGlyphPage(resolution resolution, glyphMaxSizePixels math.Size) *glyphPage {
// Handle exceptionally large glyphs.
size := math.Size{W: glyphPageWidth, H: glyphPageHeight}.Max(glyphMaxSizePixels)
size.W = align(size.W, glyphSizeAlignment)
size.H = align(size.H, glyphSizeAlignment)
return &glyphPage{
resolution: resolution,
glyphMaxSizePixels: glyphMaxSizePixels,
size: size,
image: image.NewAlpha(image.Rect(0, 0, size.W, size.H)),
offsets: make(map[rune]math.Point),
rowHeight: 0,
rast: raster.NewRasterizer(glyphMaxSizePixels.W, glyphMaxSizePixels.H),
}
}
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.")
}
func TestFreetypeNonZeroWinding(t *testing.T) {
var p Path
p.LineTo(10, 190)
draw2dbase.TraceCubic(&p, []float64{10, 190, 10, 10, 190, 10, 190, 190}, 0.5)
poly := Polygon(p.points)
color := color.RGBA{0, 0, 0, 0xff}
img := image.NewRGBA(image.Rect(0, 0, 200, 200))
rasterizer := raster.NewRasterizer(200, 200)
rasterizer.UseNonZeroWinding = true
rasterizer.Start(raster.Point{
X: raster.Fix32(10 * 256),
Y: raster.Fix32(190 * 256)})
for j := 0; j < len(poly); j = j + 2 {
rasterizer.Add1(raster.Point{
X: raster.Fix32(poly[j] * 256),
Y: raster.Fix32(poly[j+1] * 256)})
}
painter := raster.NewRGBAPainter(img)
painter.SetColor(color)
rasterizer.Rasterize(painter)
draw2dimg.SaveToPngFile("../output/raster/TestFreetypeNonZeroWinding.png", img)
}
func main() {
const (
n = 17
r = 64 * 80
)
s := fixed.Int26_6(r * math.Sqrt(2) / 2)
t := fixed.Int26_6(r * math.Tan(math.Pi/8))
m := image.NewRGBA(image.Rect(0, 0, 800, 600))
draw.Draw(m, m.Bounds(), image.NewUniform(color.RGBA{63, 63, 63, 255}), image.ZP, draw.Src)
mp := raster.NewRGBAPainter(m)
mp.SetColor(image.Black)
z := raster.NewRasterizer(800, 600)
for i := 0; i < n; i++ {
cx := fixed.Int26_6(6400 + 12800*(i%4))
cy := fixed.Int26_6(640 + 8000*(i/4))
c := fixed.Point26_6{X: cx, Y: cy}
theta := math.Pi * (0.5 + 0.5*float64(i)/(n-1))
dx := fixed.Int26_6(r * math.Cos(theta))
dy := fixed.Int26_6(r * math.Sin(theta))
d := fixed.Point26_6{X: dx, Y: dy}
// Draw a quarter-circle approximated by two quadratic segments,
// with each segment spanning 45 degrees.
z.Start(c)
z.Add1(c.Add(fixed.Point26_6{X: r, Y: 0}))
z.Add2(c.Add(fixed.Point26_6{X: r, Y: t}), c.Add(fixed.Point26_6{X: s, Y: s}))
z.Add2(c.Add(fixed.Point26_6{X: t, Y: r}), c.Add(fixed.Point26_6{X: 0, Y: r}))
// Add another quadratic segment whose angle ranges between 0 and 90
// degrees. For an explanation of the magic constants 128, 150, 181 and
// 256, read the comments in the freetype/raster package.
dot := 256 * pDot(d, fixed.Point26_6{X: 0, Y: r}) / (r * r)
multiple := fixed.Int26_6(150-(150-128)*(dot-181)/(256-181)) >> 2
z.Add2(c.Add(fixed.Point26_6{X: dx, Y: r + dy}.Mul(multiple)), c.Add(d))
// Close the curve.
z.Add1(c)
}
z.Rasterize(mp)
for i := 0; i < n; i++ {
cx := fixed.Int26_6(6400 + 12800*(i%4))
cy := fixed.Int26_6(640 + 8000*(i/4))
for j := 0; j < n; j++ {
theta := math.Pi * float64(j) / (n - 1)
dx := fixed.Int26_6(r * math.Cos(theta))
dy := fixed.Int26_6(r * math.Sin(theta))
m.Set(int((cx+dx)/64), int((cy+dy)/64), color.RGBA{255, 255, 0, 255})
}
}
// 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, m)
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.")
}
func (s *Sparkline) Draw(dst draw.Image) {
if len(s.data) == 0 {
return
}
min := s.data[0]
max := s.data[0]
for _, n := range s.data[1:] {
if n < min {
min = n
}
if n > max {
max = n
}
}
// try to be helpful when there's limited data
if max < 1.0 {
max = 1.0
}
if min > max-1.0 {
min = max - 1.0
if min < 0.0 {
min = 0.0
}
}
bounds := dst.Bounds()
dx, dy := bounds.Dx(), bounds.Dy()
tmp := image.NewRGBA(image.Rectangle{Max: image.Point{X: dx, Y: dy}})
p := raster.NewRGBAPainter(tmp)
r := raster.NewRasterizer(dx, dy)
r.UseNonZeroWinding = true
var q raster.Path
q.Start(s.scale(0, s.data[0], min, max, dx, dy))
for i, n := range s.data[1:] {
pt := s.scale(i+1, n, min, max, dx, dy)
q.Add1(pt)
}
const strokeWidth = fixed.Int26_6(5 << 6)
r.AddStroke(q, strokeWidth, raster.RoundCapper, raster.RoundJoiner)
p.SetColor(s.fg)
r.Rasterize(p)
r.Clear()
q.Clear()
headPt := s.scale(len(s.data)-1, s.data[len(s.data)-1], min, max, dx, dy)
q.Start(headPt)
// miniscule nudge so something actually is output
q.Add1(headPt.Add(fixed.Point26_6{X: 1, Y: 1}))
const headWidth = fixed.Int26_6(8 << 6)
r.AddStroke(q, headWidth, raster.RoundCapper, raster.RoundJoiner)
// TODO really decide between uint64 vs float32 vs uint32 etc
// value := uint64((s.data[len(s.data)-1] - min) / max * float32(^uint64(0)))
value := uint64(s.data[len(s.data)-1])
headColor := PickColor(s.thresholds, value)
p.SetColor(headColor)
r.Rasterize(p)
draw.Draw(dst, bounds, tmp, image.ZP, draw.Over)
}
func Handler(w http.ResponseWriter, req *http.Request) {
const size = 500
c := image.NewRGBA(image.Rect(0, 0, size, size))
white := &image.Uniform{C: color.White}
draw.Draw(c, c.Bounds(), white, image.ZP, draw.Src)
p := raster.NewRGBAPainter(c)
p.SetColor(color.Black)
r := raster.NewRasterizer(500, 500)
r.UseNonZeroWinding = true
var path raster.Path
path.Start(nudge(fixed.P(50, 50)))
path.Add1(nudge(fixed.P(50, 450)))
path.Add1(nudge(fixed.P(450, 450)))
r.AddStroke(path, fixed.I(2), raster.ButtCapper, raster.BevelJoiner)
r.Rasterize(p)
r.Clear()
p.SetColor(color.Gray16{0x7FFF})
path.Clear()
r.Clear()
path.Start(nudge(fixed.P(450, 450)))
path.Add1(nudge(fixed.P(450, 50)))
path.Add1(nudge(fixed.P(50, 50)))
r.AddStroke(path, fixed.I(1), raster.ButtCapper, raster.BevelJoiner)
r.Rasterize(p)
p.SetColor(color.Gray16{0x7FFF})
for x := 50; x <= 450; x += 50 {
path.Clear()
path.Start(nudge(fixed.P(x, 450)))
path.Add1(nudge(fixed.P(x, 460)))
r.AddStroke(path, fixed.I(1), raster.ButtCapper, raster.BevelJoiner)
}
for x := 50; x <= 450; x += 50 {
path.Clear()
path.Start(nudge(fixed.P(50, x)))
path.Add1(nudge(fixed.P(40, x)))
r.AddStroke(path, fixed.I(1), raster.ButtCapper, raster.BevelJoiner)
}
r.Rasterize(p)
p.SetColor(color.RGBA{0x00, 0x00, 0xFF, 0xFF})
r.Clear()
path.Clear()
path.Start(nudge(fixed.P(50, 450)))
path.Add1(nudge(fixed.P(450, 50)))
r.AddStroke(path, fixed.I(1), raster.ButtCapper, raster.BevelJoiner)
r.Rasterize(p)
p.SetColor(color.RGBA{0xCC, 0x00, 0x00, 0xFF})
r.Clear()
window := fixed.Rectangle26_6{fixed.P(50, 450), fixed.P(450, 50)}
// path = plotPath(ratSin, big.NewRat(0, 1), big.NewRat(-1, 1), big.NewRat(10, 1), big.NewRat(1, 1), window)
// path = plotPath(ratProb, big.NewRat(0, 1), big.NewRat(0, 1), big.NewRat(1, 1<<57), big.NewRat(1, 1<<57), window)
var lo, hi *big.Rat
var locap, hicap, scalecap string
id, _ := strconv.Atoi(req.FormValue("x"))
switch id {
case 0:
lo = big.NewRat(1<<53-1<<3, 1<<54)
hi = big.NewRat(1<<53+1<<3, 1<<54)
locap = "1/2 - 1/2^51"
hicap = "1/2 + 1/2^51"
scalecap = "1/2^53"
case 1:
lo = big.NewRat(1<<54-1<<4, 1<<54)
hi = big.NewRat(1<<54, 1<<54)
locap = "1 - 1/2^50"
hicap = "1"
scalecap = "1/2^53"
case 2:
lo = big.NewRat(0, 1<<54)
hi = big.NewRat(1<<4, 1<<54)
locap = "0"
hicap = "1/2^50"
scalecap = "1/2^53"
case 3:
lo = big.NewRat(0, 1<<54)
hi = big.NewRat(1<<2, 1<<62)
locap = "0"
hicap = "1/2^59"
scalecap = "1/2^63"
}
mode, _ := strconv.Atoi(req.FormValue("mode"))
path = plotPath(ratProb(mode), lo, lo, hi, hi, window)
r.AddStroke(path, fixed.I(1), raster.ButtCapper, raster.BevelJoiner)
r.Rasterize(p)
var modestr string
switch mode {
case 0:
modestr = "original behavior (can return 1)"
case 1:
modestr = "new behavior (too much 0)"
case 2:
modestr = "retry loop"
}
data, err := ioutil.ReadFile("/tmp/luxisr.ttf")
if err != nil {
panic(err)
}
tfont, err := freetype.ParseFont(data)
if err != nil {
panic(err)
}
const pt = 10
ft := freetype.NewContext()
ft.SetDst(c)
ft.SetDPI(100)
ft.SetFont(tfont)
ft.SetFontSize(float64(pt))
ft.SetSrc(image.NewUniform(color.Black))
ft.SetClip(image.Rect(0, 0, 0, 0))
wid, err := ft.DrawString(locap, freetype.Pt(0, 0))
if err != nil {
panic(err)
}
pp := freetype.Pt(50, 480)
pp.X -= wid.X / 2
ft.SetClip(c.Bounds())
ft.DrawString(locap, pp)
ft.SetClip(image.Rect(0, 0, 0, 0))
wid, err = ft.DrawString(hicap, freetype.Pt(0, 0))
if err != nil {
panic(err)
}
pp = freetype.Pt(450, 480)
pp.X -= wid.X / 2
ft.SetClip(c.Bounds())
ft.DrawString(hicap, pp)
r.Clear()
p.SetColor(color.Black)
path.Clear()
const dy = 5
path.Start(nudge(fixed.P(400, 400)))
path.Add1(nudge(fixed.P(400, 400-dy)))
path.Add1(nudge(fixed.P(400, 400+dy)))
path.Add1(nudge(fixed.P(400, 400)))
path.Add1(nudge(fixed.P(450, 400)))
path.Add1(nudge(fixed.P(450, 400-dy)))
path.Add1(nudge(fixed.P(450, 400+dy)))
path.Add1(nudge(fixed.P(450, 400)))
r.AddStroke(path, fixed.I(2), raster.ButtCapper, raster.BevelJoiner)
r.Rasterize(p)
ft.SetClip(image.Rect(0, 0, 0, 0))
wid, err = ft.DrawString(scalecap, freetype.Pt(0, 0))
if err != nil {
panic(err)
}
pp = freetype.Pt(425, 420)
pp.X -= wid.X / 2
ft.SetClip(c.Bounds())
ft.DrawString(scalecap, pp)
ft.SetClip(image.Rect(0, 0, 0, 0))
wid, err = ft.DrawString(modestr, freetype.Pt(0, 0))
if err != nil {
panic(err)
}
pp = freetype.Pt(250, 490)
pp.X -= wid.X / 2
ft.SetClip(c.Bounds())
ft.DrawString(modestr, pp)
w.Write(pngEncode(c))
}