github.com/aloncn/graphics-go@v0.0.1/src/image/image_test.go (about)

     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  }