1#include "SkConfig8888.h"
2
3namespace {
4
5template <int A_IDX, int R_IDX, int G_IDX, int B_IDX>
6inline uint32_t pack_config8888(uint32_t a, uint32_t r,
7                                uint32_t g, uint32_t b) {
8#ifdef SK_CPU_LENDIAN
9    return (a << (A_IDX * 8)) | (r << (R_IDX * 8)) |
10           (g << (G_IDX * 8)) | (b << (B_IDX * 8));
11#else
12    return (a << ((3-A_IDX) * 8)) | (r << ((3-R_IDX) * 8)) |
13           (g << ((3-G_IDX) * 8)) | (b << ((3-B_IDX) * 8));
14#endif
15}
16
17template <int A_IDX, int R_IDX, int G_IDX, int B_IDX>
18inline void unpack_config8888(uint32_t color,
19                              uint32_t* a, uint32_t* r,
20                              uint32_t* g, uint32_t* b) {
21#ifdef SK_CPU_LENDIAN
22    *a = (color >> (A_IDX * 8)) & 0xff;
23    *r = (color >> (R_IDX * 8)) & 0xff;
24    *g = (color >> (G_IDX * 8)) & 0xff;
25    *b = (color >> (B_IDX * 8)) & 0xff;
26#else
27    *a = (color >> ((3 - A_IDX) * 8)) & 0xff;
28    *r = (color >> ((3 - R_IDX) * 8)) & 0xff;
29    *g = (color >> ((3 - G_IDX) * 8)) & 0xff;
30    *b = (color >> ((3 - B_IDX) * 8)) & 0xff;
31#endif
32}
33
34#ifdef SK_CPU_LENDIAN
35    static const int SK_NATIVE_A_IDX = SK_A32_SHIFT / 8;
36    static const int SK_NATIVE_R_IDX = SK_R32_SHIFT / 8;
37    static const int SK_NATIVE_G_IDX = SK_G32_SHIFT / 8;
38    static const int SK_NATIVE_B_IDX = SK_B32_SHIFT / 8;
39#else
40    static const int SK_NATIVE_A_IDX = 3 - (SK_A32_SHIFT / 8);
41    static const int SK_NATIVE_R_IDX = 3 - (SK_R32_SHIFT / 8);
42    static const int SK_NATIVE_G_IDX = 3 - (SK_G32_SHIFT / 8);
43    static const int SK_NATIVE_B_IDX = 3 - (SK_B32_SHIFT / 8);
44#endif
45
46/**
47 * convert_pixel<OUT_CFG, IN_CFG converts a pixel value from one Config8888 to
48 * another. It is implemented by first expanding OUT_CFG to r, g, b, a indices
49 * and an is_premul bool as params to another template function. Then IN_CFG is
50 * expanded via another function call.
51 */
52
53template <bool OUT_PM, int OUT_A_IDX, int OUT_R_IDX, int OUT_G_IDX, int OUT_B_IDX,
54          bool IN_PM,  int IN_A_IDX,  int IN_R_IDX,  int IN_G_IDX,  int IN_B_IDX>
55inline uint32_t convert_pixel(uint32_t pixel) {
56    uint32_t a, r, g, b;
57    unpack_config8888<IN_A_IDX, IN_R_IDX, IN_G_IDX, IN_B_IDX>(pixel, &a, &r, &g, &b);
58    if (IN_PM && !OUT_PM) {
59        // We're doing the explicit divide to match WebKit layout
60        // test expectations. We can modify and rebaseline if there
61        // it can be shown that there is a more performant way to
62        // unpremul.
63        if (a) {
64            r = r * 0xff / a;
65            g = g * 0xff / a;
66            b = b * 0xff / a;
67        } else {
68            return 0;
69        }
70    } else if (!IN_PM && OUT_PM) {
71        // This matches WebKit's conversion which we are replacing.
72        // We can consider alternative rounding rules for performance.
73        r = SkMulDiv255Ceiling(r, a);
74        g = SkMulDiv255Ceiling(g, a);
75        b = SkMulDiv255Ceiling(b, a);
76    }
77    return pack_config8888<OUT_A_IDX, OUT_R_IDX, OUT_G_IDX, OUT_B_IDX>(a, r, g, b);
78}
79
80template <bool OUT_PM, int OUT_A_IDX, int OUT_R_IDX, int OUT_G_IDX, int OUT_B_IDX, SkCanvas::Config8888 IN_CFG>
81inline uint32_t convert_pixel(uint32_t pixel) {
82    switch(IN_CFG) {
83        case SkCanvas::kNative_Premul_Config8888:
84            return convert_pixel<OUT_PM, OUT_A_IDX,       OUT_R_IDX,       OUT_G_IDX,       OUT_B_IDX,
85                                 true,  SK_NATIVE_A_IDX,  SK_NATIVE_R_IDX, SK_NATIVE_G_IDX, SK_NATIVE_B_IDX>(pixel);
86            break;
87        case SkCanvas::kNative_Unpremul_Config8888:
88            return convert_pixel<OUT_PM, OUT_A_IDX,       OUT_R_IDX,       OUT_G_IDX,       OUT_B_IDX,
89                                 false,  SK_NATIVE_A_IDX, SK_NATIVE_R_IDX, SK_NATIVE_G_IDX, SK_NATIVE_B_IDX>(pixel);
90            break;
91        case SkCanvas::kBGRA_Premul_Config8888:
92            return convert_pixel<OUT_PM, OUT_A_IDX, OUT_R_IDX, OUT_G_IDX, OUT_B_IDX,
93                                 true,  3,         2,         1,         0>(pixel);
94            break;
95        case SkCanvas::kBGRA_Unpremul_Config8888:
96            return convert_pixel<OUT_PM, OUT_A_IDX, OUT_R_IDX, OUT_G_IDX, OUT_B_IDX,
97                                 false,  3,         2,         1,         0>(pixel);
98            break;
99        case SkCanvas::kRGBA_Premul_Config8888:
100            return convert_pixel<OUT_PM, OUT_A_IDX, OUT_R_IDX, OUT_G_IDX, OUT_B_IDX,
101                                 true,  3,         0,         1,         2>(pixel);
102            break;
103        case SkCanvas::kRGBA_Unpremul_Config8888:
104            return convert_pixel<OUT_PM, OUT_A_IDX, OUT_R_IDX, OUT_G_IDX, OUT_B_IDX,
105                                 false,  3,         0,         1,         2>(pixel);
106            break;
107        default:
108            SkDEBUGFAIL("Unexpected config8888");
109            return 0;
110            break;
111    }
112}
113
114template <SkCanvas::Config8888 OUT_CFG, SkCanvas::Config8888 IN_CFG>
115inline uint32_t convert_pixel(uint32_t pixel) {
116    switch(OUT_CFG) {
117        case SkCanvas::kNative_Premul_Config8888:
118            return convert_pixel<true,  SK_NATIVE_A_IDX,  SK_NATIVE_R_IDX, SK_NATIVE_G_IDX, SK_NATIVE_B_IDX, IN_CFG>(pixel);
119            break;
120        case SkCanvas::kNative_Unpremul_Config8888:
121            return convert_pixel<false,  SK_NATIVE_A_IDX,  SK_NATIVE_R_IDX, SK_NATIVE_G_IDX, SK_NATIVE_B_IDX, IN_CFG>(pixel);
122            break;
123        case SkCanvas::kBGRA_Premul_Config8888:
124            return convert_pixel<true, 3, 2, 1, 0, IN_CFG>(pixel);
125            break;
126        case SkCanvas::kBGRA_Unpremul_Config8888:
127            return convert_pixel<false, 3, 2, 1, 0, IN_CFG>(pixel);
128            break;
129        case SkCanvas::kRGBA_Premul_Config8888:
130            return convert_pixel<true, 3, 0, 1, 2, IN_CFG>(pixel);
131            break;
132        case SkCanvas::kRGBA_Unpremul_Config8888:
133            return convert_pixel<false, 3, 0, 1, 2, IN_CFG>(pixel);
134            break;
135        default:
136            SkDEBUGFAIL("Unexpected config8888");
137            return 0;
138            break;
139    }
140}
141
142/**
143 * SkConvertConfig8888Pixels has 6 * 6 possible combinations of src and dst
144 * configs. Each is implemented as an instantiation templated function. Two
145 * levels of switch statements are used to select the correct instantiation, one
146 * for the src config and one for the dst config.
147 */
148
149template <SkCanvas::Config8888 DST_CFG, SkCanvas::Config8888 SRC_CFG>
150inline void convert_config8888(uint32_t* dstPixels,
151                               size_t dstRowBytes,
152                               const uint32_t* srcPixels,
153                               size_t srcRowBytes,
154                               int width,
155                               int height) {
156    intptr_t dstPix = reinterpret_cast<intptr_t>(dstPixels);
157    intptr_t srcPix = reinterpret_cast<intptr_t>(srcPixels);
158
159    for (int y = 0; y < height; ++y) {
160        srcPixels = reinterpret_cast<const uint32_t*>(srcPix);
161        dstPixels = reinterpret_cast<uint32_t*>(dstPix);
162        for (int x = 0; x < width; ++x) {
163            dstPixels[x] = convert_pixel<DST_CFG, SRC_CFG>(srcPixels[x]);
164        }
165        dstPix += dstRowBytes;
166        srcPix += srcRowBytes;
167    }
168}
169
170template <SkCanvas::Config8888 SRC_CFG>
171inline void convert_config8888(uint32_t* dstPixels,
172                               size_t dstRowBytes,
173                               SkCanvas::Config8888 dstConfig,
174                               const uint32_t* srcPixels,
175                               size_t srcRowBytes,
176                               int width,
177                               int height) {
178    switch(dstConfig) {
179        case SkCanvas::kNative_Premul_Config8888:
180            convert_config8888<SkCanvas::kNative_Premul_Config8888, SRC_CFG>(dstPixels, dstRowBytes, srcPixels, srcRowBytes, width, height);
181            break;
182        case SkCanvas::kNative_Unpremul_Config8888:
183            convert_config8888<SkCanvas::kNative_Unpremul_Config8888, SRC_CFG>(dstPixels, dstRowBytes, srcPixels, srcRowBytes, width, height);
184            break;
185        case SkCanvas::kBGRA_Premul_Config8888:
186            convert_config8888<SkCanvas::kBGRA_Premul_Config8888, SRC_CFG>(dstPixels, dstRowBytes, srcPixels, srcRowBytes, width, height);
187            break;
188        case SkCanvas::kBGRA_Unpremul_Config8888:
189            convert_config8888<SkCanvas::kBGRA_Unpremul_Config8888, SRC_CFG>(dstPixels, dstRowBytes, srcPixels, srcRowBytes, width, height);
190            break;
191        case SkCanvas::kRGBA_Premul_Config8888:
192            convert_config8888<SkCanvas::kRGBA_Premul_Config8888, SRC_CFG>(dstPixels, dstRowBytes, srcPixels, srcRowBytes, width, height);
193            break;
194        case SkCanvas::kRGBA_Unpremul_Config8888:
195            convert_config8888<SkCanvas::kRGBA_Unpremul_Config8888, SRC_CFG>(dstPixels, dstRowBytes, srcPixels, srcRowBytes, width, height);
196            break;
197        default:
198            SkDEBUGFAIL("Unexpected config8888");
199            break;
200    }
201}
202
203}
204
205void SkConvertConfig8888Pixels(uint32_t* dstPixels,
206                               size_t dstRowBytes,
207                               SkCanvas::Config8888 dstConfig,
208                               const uint32_t* srcPixels,
209                               size_t srcRowBytes,
210                               SkCanvas::Config8888 srcConfig,
211                               int width,
212                               int height) {
213    if (srcConfig == dstConfig) {
214        if (srcPixels == dstPixels) {
215            return;
216        }
217        if (dstRowBytes == srcRowBytes &&
218            4U * width == srcRowBytes) {
219            memcpy(dstPixels, srcPixels, srcRowBytes * height);
220            return;
221        } else {
222            intptr_t srcPix = reinterpret_cast<intptr_t>(srcPixels);
223            intptr_t dstPix = reinterpret_cast<intptr_t>(dstPixels);
224            for (int y = 0; y < height; ++y) {
225                srcPixels = reinterpret_cast<const uint32_t*>(srcPix);
226                dstPixels = reinterpret_cast<uint32_t*>(dstPix);
227                memcpy(dstPixels, srcPixels, 4 * width);
228                srcPix += srcRowBytes;
229                dstPix += dstRowBytes;
230            }
231            return;
232        }
233    }
234    switch(srcConfig) {
235        case SkCanvas::kNative_Premul_Config8888:
236            convert_config8888<SkCanvas::kNative_Premul_Config8888>(dstPixels, dstRowBytes, dstConfig, srcPixels, srcRowBytes, width, height);
237            break;
238        case SkCanvas::kNative_Unpremul_Config8888:
239            convert_config8888<SkCanvas::kNative_Unpremul_Config8888>(dstPixels, dstRowBytes, dstConfig, srcPixels, srcRowBytes, width, height);
240            break;
241        case SkCanvas::kBGRA_Premul_Config8888:
242            convert_config8888<SkCanvas::kBGRA_Premul_Config8888>(dstPixels, dstRowBytes, dstConfig, srcPixels, srcRowBytes, width, height);
243            break;
244        case SkCanvas::kBGRA_Unpremul_Config8888:
245            convert_config8888<SkCanvas::kBGRA_Unpremul_Config8888>(dstPixels, dstRowBytes, dstConfig, srcPixels, srcRowBytes, width, height);
246            break;
247        case SkCanvas::kRGBA_Premul_Config8888:
248            convert_config8888<SkCanvas::kRGBA_Premul_Config8888>(dstPixels, dstRowBytes, dstConfig, srcPixels, srcRowBytes, width, height);
249            break;
250        case SkCanvas::kRGBA_Unpremul_Config8888:
251            convert_config8888<SkCanvas::kRGBA_Unpremul_Config8888>(dstPixels, dstRowBytes, dstConfig, srcPixels, srcRowBytes, width, height);
252            break;
253        default:
254            SkDEBUGFAIL("Unexpected config8888");
255            break;
256    }
257}
258
259uint32_t SkPackConfig8888(SkCanvas::Config8888 config,
260                          uint32_t a,
261                          uint32_t r,
262                          uint32_t g,
263                          uint32_t b) {
264    switch (config) {
265        case SkCanvas::kNative_Premul_Config8888:
266        case SkCanvas::kNative_Unpremul_Config8888:
267            return pack_config8888<SK_NATIVE_A_IDX,
268                                   SK_NATIVE_R_IDX,
269                                   SK_NATIVE_G_IDX,
270                                   SK_NATIVE_B_IDX>(a, r, g, b);
271        case SkCanvas::kBGRA_Premul_Config8888:
272        case SkCanvas::kBGRA_Unpremul_Config8888:
273            return pack_config8888<3, 2, 1, 0>(a, r, g, b);
274        case SkCanvas::kRGBA_Premul_Config8888:
275        case SkCanvas::kRGBA_Unpremul_Config8888:
276            return pack_config8888<3, 0, 1, 2>(a, r, g, b);
277        default:
278            SkDEBUGFAIL("Unexpected config8888");
279            return 0;
280    }
281}
282