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// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package draw
import (
"bytes"
"image"
"image/color"
"testing"
)
// TestFastPaths tests that the fast path implementations produce identical
// results to the generic implementation.
func TestFastPaths(t *testing.T) {
drs := []image.Rectangle{
image.Rect(0, 0, 10, 10), // The dst bounds.
image.Rect(3, 4, 8, 6), // A strict subset of the dst bounds.
image.Rect(-3, -5, 2, 4), // Partial out-of-bounds #0.
image.Rect(4, -2, 6, 12), // Partial out-of-bounds #1.
image.Rect(12, 14, 23, 45), // Complete out-of-bounds.
image.Rect(5, 5, 5, 5), // Empty.
}
srs := []image.Rectangle{
image.Rect(0, 0, 12, 9), // The src bounds.
image.Rect(2, 2, 10, 8), // A strict subset of the src bounds.
image.Rect(10, 5, 20, 20), // Partial out-of-bounds #0.
image.Rect(-40, 0, 40, 8), // Partial out-of-bounds #1.
image.Rect(-8, -8, -4, -4), // Complete out-of-bounds.
image.Rect(5, 5, 5, 5), // Empty.
}
srcfs := []func(image.Rectangle) (image.Image, error){
srcGray,
srcNRGBA,
srcRGBA,
srcUnif,
srcYCbCr,
}
var srcs []image.Image
for _, srcf := range srcfs {
src, err := srcf(srs[0])
if err != nil {
t.Fatal(err)
}
srcs = append(srcs, src)
}
qs := []Interpolator{
NearestNeighbor,
ApproxBiLinear,
CatmullRom,
}
ops := []Op{
Over,
Src,
}
blue := image.NewUniform(color.RGBA{0x11, 0x22, 0x44, 0x7f})
for _, dr := range drs {
for _, src := range srcs {
for _, sr := range srs {
for _, transform := range []bool{false, true} {
for _, q := range qs {
for _, op := range ops {
dst0 := image.NewRGBA(drs[0])
dst1 := image.NewRGBA(drs[0])
Draw(dst0, dst0.Bounds(), blue, image.Point{}, Src)
Draw(dstWrapper{dst1}, dst1.Bounds(), srcWrapper{blue}, image.Point{}, Src)
if transform {
m := transformMatrix(3.75, 2, 1)
q.Transform(dst0, m, src, sr, op, nil)
q.Transform(dstWrapper{dst1}, m, srcWrapper{src}, sr, op, nil)
} else {
q.Scale(dst0, dr, src, sr, op, nil)
q.Scale(dstWrapper{dst1}, dr, srcWrapper{src}, sr, op, nil)
}
if !bytes.Equal(dst0.Pix, dst1.Pix) {
t.Errorf("pix differ for dr=%v, src=%T, sr=%v, transform=%t, q=%T",
dr, src, sr, transform, q)
}
}
}
}
}
}
}
}