1 /*
2 * Copyright 2012 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8 // This test is specific to the GPU backend.
9 #if SK_SUPPORT_GPU && !defined(SK_BUILD_FOR_ANDROID)
10
11 #include "GrContextFactory.h"
12 #include "SkGpuDevice.h"
13 #include "Test.h"
14
15 static const int X_SIZE = 12;
16 static const int Y_SIZE = 12;
17
DEF_GPUTEST(ReadWriteAlpha,reporter,factory)18 DEF_GPUTEST(ReadWriteAlpha, reporter, factory) {
19 for (int type = 0; type < GrContextFactory::kLastGLContextType; ++type) {
20 GrContextFactory::GLContextType glType = static_cast<GrContextFactory::GLContextType>(type);
21 if (!GrContextFactory::IsRenderingGLContext(glType)) {
22 continue;
23 }
24 GrContext* context = factory->get(glType);
25 if (NULL == context) {
26 continue;
27 }
28
29 unsigned char textureData[X_SIZE][Y_SIZE];
30
31 memset(textureData, 0, X_SIZE * Y_SIZE);
32
33 GrTextureDesc desc;
34
35 // let Skia know we will be using this texture as a render target
36 desc.fFlags = kRenderTarget_GrTextureFlagBit;
37 // it is a single channel texture
38 desc.fConfig = kAlpha_8_GrPixelConfig;
39 desc.fWidth = X_SIZE;
40 desc.fHeight = Y_SIZE;
41
42 // We are initializing the texture with zeros here
43 GrTexture* texture = context->createUncachedTexture(desc, textureData, 0);
44 if (!texture) {
45 return;
46 }
47
48 SkAutoTUnref<GrTexture> au(texture);
49
50 // create a distinctive texture
51 for (int y = 0; y < Y_SIZE; ++y) {
52 for (int x = 0; x < X_SIZE; ++x) {
53 textureData[x][y] = x*Y_SIZE+y;
54 }
55 }
56
57 // upload the texture
58 texture->writePixels(0, 0, desc.fWidth, desc.fHeight, desc.fConfig,
59 textureData, 0);
60
61 unsigned char readback[X_SIZE][Y_SIZE];
62
63 // clear readback to something non-zero so we can detect readback failures
64 memset(readback, 0x1, X_SIZE * Y_SIZE);
65
66 // read the texture back
67 texture->readPixels(0, 0, desc.fWidth, desc.fHeight, desc.fConfig,
68 readback, 0);
69
70 // make sure the original & read back versions match
71 bool match = true;
72
73 for (int y = 0; y < Y_SIZE; ++y) {
74 for (int x = 0; x < X_SIZE; ++x) {
75 if (textureData[x][y] != readback[x][y]) {
76 match = false;
77 }
78 }
79 }
80
81 REPORTER_ASSERT(reporter, match);
82
83 // Now try writing on the single channel texture
84 SkAutoTUnref<SkBaseDevice> device(SkGpuDevice::Create(texture->asRenderTarget(),
85 SkSurfaceProps(SkSurfaceProps::kLegacyFontHost_InitType)));
86 SkCanvas canvas(device);
87
88 SkPaint paint;
89
90 const SkRect rect = SkRect::MakeLTRB(-10, -10, X_SIZE + 10, Y_SIZE + 10);
91
92 paint.setColor(SK_ColorWHITE);
93
94 canvas.drawRect(rect, paint);
95
96 texture->readPixels(0, 0, desc.fWidth, desc.fHeight, desc.fConfig,
97 readback, 0);
98
99 match = true;
100
101 for (int y = 0; y < Y_SIZE; ++y) {
102 for (int x = 0; x < X_SIZE; ++x) {
103 if (0xFF != readback[x][y]) {
104 match = false;
105 }
106 }
107 }
108
109 REPORTER_ASSERT(reporter, match);
110 }
111 }
112
113 #endif
114