libgo/go/image/image_test.go

   1 // Copyright 2011 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 package image
   6
   7 import (
   8         "image/color"
   9         "testing"
  10 )
  11
  12 type image interface {
  13         Image
  14         Opaque() bool
  15         Set(int, int, color.Color)
  16         SubImage(Rectangle) Image
  17 }
  18
  19 func cmp(t *testing.T, cm color.Model, c0, c1 color.Color) bool {
  20         r0, g0, b0, a0 := cm.Convert(c0).RGBA()
  21         r1, g1, b1, a1 := cm.Convert(c1).RGBA()
  22         return r0 == r1 && g0 == g1 && b0 == b1 && a0 == a1
  23 }
  24
  25 func TestImage(t *testing.T) {
  26         testImage := []image{
  27                 NewRGBA(Rect(0, 0, 10, 10)),
  28                 NewRGBA64(Rect(0, 0, 10, 10)),
  29                 NewNRGBA(Rect(0, 0, 10, 10)),
  30                 NewNRGBA64(Rect(0, 0, 10, 10)),
  31                 NewAlpha(Rect(0, 0, 10, 10)),
  32                 NewAlpha16(Rect(0, 0, 10, 10)),
  33                 NewGray(Rect(0, 0, 10, 10)),
  34                 NewGray16(Rect(0, 0, 10, 10)),
  35                 NewPaletted(Rect(0, 0, 10, 10), color.Palette{
  36                         Transparent,
  37                         Opaque,
  38                 }),
  39         }
  40         for _, m := range testImage {
  41                 if !Rect(0, 0, 10, 10).Eq(m.Bounds()) {
  42                         t.Errorf("%T: want bounds %v, got %v", m, Rect(0, 0, 10, 10), m.Bounds())
  43                         continue
  44                 }
  45                 if !cmp(t, m.ColorModel(), Transparent, m.At(6, 3)) {
  46                         t.Errorf("%T: at (6, 3), want a zero color, got %v", m, m.At(6, 3))
  47                         continue
  48                 }
  49                 m.Set(6, 3, Opaque)
  50                 if !cmp(t, m.ColorModel(), Opaque, m.At(6, 3)) {
  51                         t.Errorf("%T: at (6, 3), want a non-zero color, got %v", m, m.At(6, 3))
  52                         continue
  53                 }
  54                 if !m.SubImage(Rect(6, 3, 7, 4)).(image).Opaque() {
  55                         t.Errorf("%T: at (6, 3) was not opaque", m)
  56                         continue
  57                 }
  58                 m = m.SubImage(Rect(3, 2, 9, 8)).(image)
  59                 if !Rect(3, 2, 9, 8).Eq(m.Bounds()) {
  60                         t.Errorf("%T: sub-image want bounds %v, got %v", m, Rect(3, 2, 9, 8), m.Bounds())
  61                         continue
  62                 }
  63                 if !cmp(t, m.ColorModel(), Opaque, m.At(6, 3)) {
  64                         t.Errorf("%T: sub-image at (6, 3), want a non-zero color, got %v", m, m.At(6, 3))
  65                         continue
  66                 }
  67                 if !cmp(t, m.ColorModel(), Transparent, m.At(3, 3)) {
  68                         t.Errorf("%T: sub-image at (3, 3), want a zero color, got %v", m, m.At(3, 3))
  69                         continue
  70                 }
  71                 m.Set(3, 3, Opaque)
  72                 if !cmp(t, m.ColorModel(), Opaque, m.At(3, 3)) {
  73                         t.Errorf("%T: sub-image at (3, 3), want a non-zero color, got %v", m, m.At(3, 3))
  74                         continue
  75                 }
  76                 // Test that taking an empty sub-image starting at a corner does not panic.
  77                 m.SubImage(Rect(0, 0, 0, 0))
  78                 m.SubImage(Rect(10, 0, 10, 0))
  79                 m.SubImage(Rect(0, 10, 0, 10))
  80                 m.SubImage(Rect(10, 10, 10, 10))
  81         }
  82 }
  83
  84 func Test16BitsPerColorChannel(t *testing.T) {
  85         testColorModel := []color.Model{
  86                 color.RGBA64Model,
  87                 color.NRGBA64Model,
  88                 color.Alpha16Model,
  89                 color.Gray16Model,
  90         }
  91         for _, cm := range testColorModel {
  92                 c := cm.Convert(color.RGBA64{0x1234, 0x1234, 0x1234, 0x1234}) // Premultiplied alpha.
  93                 r, _, _, _ := c.RGBA()
  94                 if r != 0x1234 {
  95                         t.Errorf("%T: want red value 0x%04x got 0x%04x", c, 0x1234, r)
  96                         continue
  97                 }
  98         }
  99         testImage := []image{
 100                 NewRGBA64(Rect(0, 0, 10, 10)),
 101                 NewNRGBA64(Rect(0, 0, 10, 10)),
 102                 NewAlpha16(Rect(0, 0, 10, 10)),
 103                 NewGray16(Rect(0, 0, 10, 10)),
 104         }
 105         for _, m := range testImage {
 106                 m.Set(1, 2, color.NRGBA64{0xffff, 0xffff, 0xffff, 0x1357}) // Non-premultiplied alpha.
 107                 r, _, _, _ := m.At(1, 2).RGBA()
 108                 if r != 0x1357 {
 109                         t.Errorf("%T: want red value 0x%04x got 0x%04x", m, 0x1357, r)
 110                         continue
 111                 }
 112         }
 113 }