1/*
2 * Copyright 2011 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#include "SkBitmapDevice.h"
9#include "SkCanvas.h"
10#include "SkConfig8888.h"
11#include "Test.h"
12#include "sk_tool_utils.h"
13
14#if SK_SUPPORT_GPU
15#include "GrContextFactory.h"
16#include "SkGpuDevice.h"
17#endif
18
19static uint32_t pack_unpremul_rgba(SkColor c) {
20    uint32_t packed;
21    uint8_t* byte = reinterpret_cast<uint8_t*>(&packed);
22    byte[0] = SkColorGetR(c);
23    byte[1] = SkColorGetG(c);
24    byte[2] = SkColorGetB(c);
25    byte[3] = SkColorGetA(c);
26    return packed;
27}
28
29static uint32_t pack_unpremul_bgra(SkColor c) {
30    uint32_t packed;
31    uint8_t* byte = reinterpret_cast<uint8_t*>(&packed);
32    byte[0] = SkColorGetB(c);
33    byte[1] = SkColorGetG(c);
34    byte[2] = SkColorGetR(c);
35    byte[3] = SkColorGetA(c);
36    return packed;
37}
38
39typedef uint32_t (*PackUnpremulProc)(SkColor);
40
41const struct {
42    SkColorType         fColorType;
43    PackUnpremulProc    fPackProc;
44} gUnpremul[] = {
45    { kRGBA_8888_SkColorType, pack_unpremul_rgba },
46    { kBGRA_8888_SkColorType, pack_unpremul_bgra },
47};
48
49static void fillCanvas(SkCanvas* canvas, SkColorType colorType, PackUnpremulProc proc) {
50    // Don't strictly need a bitmap, but its a handy way to allocate the pixels
51    SkBitmap bmp;
52    bmp.allocN32Pixels(256, 256);
53
54    for (int a = 0; a < 256; ++a) {
55        uint32_t* pixels = bmp.getAddr32(0, a);
56        for (int r = 0; r < 256; ++r) {
57            pixels[r] = proc(SkColorSetARGB(a, r, 0, 0));
58        }
59    }
60
61    SkImageInfo info = bmp.info();
62    info.fColorType = colorType;
63    info.fAlphaType = kUnpremul_SkAlphaType;
64    canvas->writePixels(info, bmp.getPixels(), bmp.rowBytes(), 0, 0);
65}
66
67DEF_GPUTEST(PremulAlphaRoundTrip, reporter, factory) {
68    const SkImageInfo info = SkImageInfo::MakeN32Premul(256, 256);
69
70    SkAutoTUnref<SkBaseDevice> device;
71    for (int dtype = 0; dtype < 2; ++dtype) {
72
73        int glCtxTypeCnt = 1;
74#if SK_SUPPORT_GPU
75        if (0 != dtype)  {
76            glCtxTypeCnt = GrContextFactory::kGLContextTypeCnt;
77        }
78#endif
79        for (int glCtxType = 0; glCtxType < glCtxTypeCnt; ++glCtxType) {
80            if (0 == dtype) {
81                device.reset(SkBitmapDevice::Create(info));
82            } else {
83#if SK_SUPPORT_GPU
84                GrContextFactory::GLContextType type =
85                    static_cast<GrContextFactory::GLContextType>(glCtxType);
86                if (!GrContextFactory::IsRenderingGLContext(type)) {
87                    continue;
88                }
89                GrContext* context = factory->get(type);
90                if (NULL == context) {
91                    continue;
92                }
93
94                device.reset(SkGpuDevice::Create(context, info, 0));
95#else
96                continue;
97#endif
98            }
99            SkCanvas canvas(device);
100
101            for (size_t upmaIdx = 0; upmaIdx < SK_ARRAY_COUNT(gUnpremul); ++upmaIdx) {
102                fillCanvas(&canvas, gUnpremul[upmaIdx].fColorType, gUnpremul[upmaIdx].fPackProc);
103
104                const SkImageInfo info = SkImageInfo::Make(256, 256, gUnpremul[upmaIdx].fColorType,
105                                                           kUnpremul_SkAlphaType);
106                SkBitmap readBmp1;
107                readBmp1.allocPixels(info);
108                SkBitmap readBmp2;
109                readBmp2.allocPixels(info);
110
111                readBmp1.eraseColor(0);
112                readBmp2.eraseColor(0);
113
114                canvas.readPixels(&readBmp1, 0, 0);
115                sk_tool_utils::write_pixels(&canvas, readBmp1, 0, 0, gUnpremul[upmaIdx].fColorType,
116                                            kUnpremul_SkAlphaType);
117                canvas.readPixels(&readBmp2, 0, 0);
118
119                bool success = true;
120                for (int y = 0; y < 256 && success; ++y) {
121                    const uint32_t* pixels1 = readBmp1.getAddr32(0, y);
122                    const uint32_t* pixels2 = readBmp2.getAddr32(0, y);
123                    for (int x = 0; x < 256 && success; ++x) {
124                        REPORTER_ASSERT(reporter, success = pixels1[x] == pixels2[x]);
125                    }
126                }
127            }
128        }
129    }
130}
131