vector: add benchmarks.

Change-Id: I4946ccc3a915c7e9365cd5fe860da673a2270fbb
Reviewed-on: https://go-review.googlesource.com/29631
Reviewed-by: David Crawshaw <crawshaw@golang.org>
This commit is contained in:
Nigel Tao 2016-09-23 11:03:00 +10:00
parent cd8486aac9
commit 50ce1ebf58

View File

@ -8,8 +8,10 @@ package vector
import ( import (
"image" "image"
"image/color"
"image/draw" "image/draw"
"image/png" "image/png"
"math"
"os" "os"
"testing" "testing"
@ -93,3 +95,109 @@ func TestBasicPath(t *testing.T) {
} }
} }
} }
const (
benchmarkGlyphWidth = 893
benchmarkGlyphHeight = 1122
)
// benchmarkGlyphData is the 'a' glyph from the Roboto Regular font, translated
// so that its top left corner is (0, 0).
var benchmarkGlyphData = []struct {
// n being 0, 1 or 2 means moveTo, lineTo or quadTo.
n uint32
p f32.Vec2
q f32.Vec2
}{
{0, f32.Vec2{699, 1102}, f32.Vec2{0, 0}},
{2, f32.Vec2{683, 1070}, f32.Vec2{673, 988}},
{2, f32.Vec2{544, 1122}, f32.Vec2{365, 1122}},
{2, f32.Vec2{205, 1122}, f32.Vec2{102.5, 1031.5}},
{2, f32.Vec2{0, 941}, f32.Vec2{0, 802}},
{2, f32.Vec2{0, 633}, f32.Vec2{128.5, 539.5}},
{2, f32.Vec2{257, 446}, f32.Vec2{490, 446}},
{1, f32.Vec2{670, 446}, f32.Vec2{0, 0}},
{1, f32.Vec2{670, 361}, f32.Vec2{0, 0}},
{2, f32.Vec2{670, 264}, f32.Vec2{612, 206.5}},
{2, f32.Vec2{554, 149}, f32.Vec2{441, 149}},
{2, f32.Vec2{342, 149}, f32.Vec2{275, 199}},
{2, f32.Vec2{208, 249}, f32.Vec2{208, 320}},
{1, f32.Vec2{22, 320}, f32.Vec2{0, 0}},
{2, f32.Vec2{22, 239}, f32.Vec2{79.5, 163.5}},
{2, f32.Vec2{137, 88}, f32.Vec2{235.5, 44}},
{2, f32.Vec2{334, 0}, f32.Vec2{452, 0}},
{2, f32.Vec2{639, 0}, f32.Vec2{745, 93.5}},
{2, f32.Vec2{851, 187}, f32.Vec2{855, 351}},
{1, f32.Vec2{855, 849}, f32.Vec2{0, 0}},
{2, f32.Vec2{855, 998}, f32.Vec2{893, 1086}},
{1, f32.Vec2{893, 1102}, f32.Vec2{0, 0}},
{1, f32.Vec2{699, 1102}, f32.Vec2{0, 0}},
{0, f32.Vec2{392, 961}, f32.Vec2{0, 0}},
{2, f32.Vec2{479, 961}, f32.Vec2{557, 916}},
{2, f32.Vec2{635, 871}, f32.Vec2{670, 799}},
{1, f32.Vec2{670, 577}, f32.Vec2{0, 0}},
{1, f32.Vec2{525, 577}, f32.Vec2{0, 0}},
{2, f32.Vec2{185, 577}, f32.Vec2{185, 776}},
{2, f32.Vec2{185, 863}, f32.Vec2{243, 912}},
{2, f32.Vec2{301, 961}, f32.Vec2{392, 961}},
}
// benchGlyph benchmarks rasterizing a TrueType glyph.
//
// Note that, compared to the github.com/google/font-go prototype, the height
// here is the height of the bounding box, not the pixels per em used to scale
// a glyph's vectors. A height of 64 corresponds to a ppem greater than 64.
func benchGlyph(b *testing.B, cm color.Model, height int, op draw.Op) {
scale := float32(height) / benchmarkGlyphHeight
// Clone the benchmarkGlyphData slice and scale its coordinates.
data := append(benchmarkGlyphData[:0:0], benchmarkGlyphData...)
for i := range data {
data[i].p[0] *= scale
data[i].p[1] *= scale
data[i].q[0] *= scale
data[i].q[1] *= scale
}
width := int(math.Ceil(float64(benchmarkGlyphWidth * scale)))
z := NewRasterizer(width, height)
dst, src := draw.Image(nil), image.Image(nil)
switch cm {
case color.AlphaModel:
dst = image.NewAlpha(z.Bounds())
src = image.Opaque
default:
b.Fatal("unsupported color model")
}
b.ResetTimer()
for i := 0; i < b.N; i++ {
z.Reset(width, height)
z.DrawOp = op
for _, d := range data {
switch d.n {
case 0:
z.MoveTo(d.p)
case 1:
z.LineTo(d.p)
case 2:
z.QuadTo(d.p, d.q)
}
}
z.Draw(dst, dst.Bounds(), src, image.Point{})
}
}
func BenchmarkGlyphAlpha16Over(b *testing.B) { benchGlyph(b, color.AlphaModel, 16, draw.Over) }
func BenchmarkGlyphAlpha16Src(b *testing.B) { benchGlyph(b, color.AlphaModel, 16, draw.Src) }
func BenchmarkGlyphAlpha32Over(b *testing.B) { benchGlyph(b, color.AlphaModel, 32, draw.Over) }
func BenchmarkGlyphAlpha32Src(b *testing.B) { benchGlyph(b, color.AlphaModel, 32, draw.Src) }
func BenchmarkGlyphAlpha64Over(b *testing.B) { benchGlyph(b, color.AlphaModel, 64, draw.Over) }
func BenchmarkGlyphAlpha64Src(b *testing.B) { benchGlyph(b, color.AlphaModel, 64, draw.Src) }
func BenchmarkGlyphAlpha128Over(b *testing.B) { benchGlyph(b, color.AlphaModel, 128, draw.Over) }
func BenchmarkGlyphAlpha128Src(b *testing.B) { benchGlyph(b, color.AlphaModel, 128, draw.Src) }
func BenchmarkGlyphAlpha256Over(b *testing.B) { benchGlyph(b, color.AlphaModel, 256, draw.Over) }
func BenchmarkGlyphAlpha256Src(b *testing.B) { benchGlyph(b, color.AlphaModel, 256, draw.Src) }
// TODO: color.RGBAModel benchmarks.