1#include "SkConfig8888.h"
2#include "SkMathPriv.h"
3#include "SkUnPreMultiply.h"
4
5namespace {
6
7template <int A_IDX, int R_IDX, int G_IDX, int B_IDX>
8inline uint32_t pack_config8888(uint32_t a, uint32_t r,
9                                uint32_t g, uint32_t b) {
10#ifdef SK_CPU_LENDIAN
11    return (a << (A_IDX * 8)) | (r << (R_IDX * 8)) |
12           (g << (G_IDX * 8)) | (b << (B_IDX * 8));
13#else
14    return (a << ((3-A_IDX) * 8)) | (r << ((3-R_IDX) * 8)) |
15           (g << ((3-G_IDX) * 8)) | (b << ((3-B_IDX) * 8));
16#endif
17}
18
19template <int A_IDX, int R_IDX, int G_IDX, int B_IDX>
20inline void unpack_config8888(uint32_t color,
21                              uint32_t* a, uint32_t* r,
22                              uint32_t* g, uint32_t* b) {
23#ifdef SK_CPU_LENDIAN
24    *a = (color >> (A_IDX * 8)) & 0xff;
25    *r = (color >> (R_IDX * 8)) & 0xff;
26    *g = (color >> (G_IDX * 8)) & 0xff;
27    *b = (color >> (B_IDX * 8)) & 0xff;
28#else
29    *a = (color >> ((3 - A_IDX) * 8)) & 0xff;
30    *r = (color >> ((3 - R_IDX) * 8)) & 0xff;
31    *g = (color >> ((3 - G_IDX) * 8)) & 0xff;
32    *b = (color >> ((3 - B_IDX) * 8)) & 0xff;
33#endif
34}
35
36#ifdef SK_CPU_LENDIAN
37    static const int SK_NATIVE_A_IDX = SK_A32_SHIFT / 8;
38    static const int SK_NATIVE_R_IDX = SK_R32_SHIFT / 8;
39    static const int SK_NATIVE_G_IDX = SK_G32_SHIFT / 8;
40    static const int SK_NATIVE_B_IDX = SK_B32_SHIFT / 8;
41#else
42    static const int SK_NATIVE_A_IDX = 3 - (SK_A32_SHIFT / 8);
43    static const int SK_NATIVE_R_IDX = 3 - (SK_R32_SHIFT / 8);
44    static const int SK_NATIVE_G_IDX = 3 - (SK_G32_SHIFT / 8);
45    static const int SK_NATIVE_B_IDX = 3 - (SK_B32_SHIFT / 8);
46#endif
47
48/**
49 * convert_pixel<OUT_CFG, IN_CFG converts a pixel value from one Config8888 to
50 * another. It is implemented by first expanding OUT_CFG to r, g, b, a indices
51 * and an is_premul bool as params to another template function. Then IN_CFG is
52 * expanded via another function call.
53 */
54
55template <bool OUT_PM, int OUT_A_IDX, int OUT_R_IDX, int OUT_G_IDX, int OUT_B_IDX,
56          bool IN_PM,  int IN_A_IDX,  int IN_R_IDX,  int IN_G_IDX,  int IN_B_IDX>
57inline uint32_t convert_pixel(uint32_t pixel) {
58    uint32_t a, r, g, b;
59    unpack_config8888<IN_A_IDX, IN_R_IDX, IN_G_IDX, IN_B_IDX>(pixel, &a, &r, &g, &b);
60    if (IN_PM && !OUT_PM) {
61        // Using SkUnPreMultiply::ApplyScale is faster than (value * 0xff) / a.
62        if (a) {
63            SkUnPreMultiply::Scale scale = SkUnPreMultiply::GetScale(a);
64            r = SkUnPreMultiply::ApplyScale(scale, r);
65            g = SkUnPreMultiply::ApplyScale(scale, g);
66            b = SkUnPreMultiply::ApplyScale(scale, b);
67        } else {
68            return 0;
69        }
70    } else if (!IN_PM && OUT_PM) {
71        // This matches SkUnPreMultiply conversion which we are replacing.
72        r = SkMulDiv255Round(r, a);
73        g = SkMulDiv255Round(g, a);
74        b = SkMulDiv255Round(b, a);
75    }
76    return pack_config8888<OUT_A_IDX, OUT_R_IDX, OUT_G_IDX, OUT_B_IDX>(a, r, g, b);
77}
78
79template <bool OUT_PM, int OUT_A_IDX, int OUT_R_IDX, int OUT_G_IDX, int OUT_B_IDX, SkCanvas::Config8888 IN_CFG>
80inline uint32_t convert_pixel(uint32_t pixel) {
81    switch(IN_CFG) {
82        case SkCanvas::kNative_Premul_Config8888:
83            return convert_pixel<OUT_PM, OUT_A_IDX,       OUT_R_IDX,       OUT_G_IDX,       OUT_B_IDX,
84                                 true,  SK_NATIVE_A_IDX,  SK_NATIVE_R_IDX, SK_NATIVE_G_IDX, SK_NATIVE_B_IDX>(pixel);
85            break;
86        case SkCanvas::kNative_Unpremul_Config8888:
87            return convert_pixel<OUT_PM, OUT_A_IDX,       OUT_R_IDX,       OUT_G_IDX,       OUT_B_IDX,
88                                 false,  SK_NATIVE_A_IDX, SK_NATIVE_R_IDX, SK_NATIVE_G_IDX, SK_NATIVE_B_IDX>(pixel);
89            break;
90        case SkCanvas::kBGRA_Premul_Config8888:
91            return convert_pixel<OUT_PM, OUT_A_IDX, OUT_R_IDX, OUT_G_IDX, OUT_B_IDX,
92                                 true,  3,         2,         1,         0>(pixel);
93            break;
94        case SkCanvas::kBGRA_Unpremul_Config8888:
95            return convert_pixel<OUT_PM, OUT_A_IDX, OUT_R_IDX, OUT_G_IDX, OUT_B_IDX,
96                                 false,  3,         2,         1,         0>(pixel);
97            break;
98        case SkCanvas::kRGBA_Premul_Config8888:
99            return convert_pixel<OUT_PM, OUT_A_IDX, OUT_R_IDX, OUT_G_IDX, OUT_B_IDX,
100                                 true,  3,         0,         1,         2>(pixel);
101            break;
102        case SkCanvas::kRGBA_Unpremul_Config8888:
103            return convert_pixel<OUT_PM, OUT_A_IDX, OUT_R_IDX, OUT_G_IDX, OUT_B_IDX,
104                                 false,  3,         0,         1,         2>(pixel);
105            break;
106        default:
107            SkDEBUGFAIL("Unexpected config8888");
108            return 0;
109            break;
110    }
111}
112
113template <SkCanvas::Config8888 OUT_CFG, SkCanvas::Config8888 IN_CFG>
114inline uint32_t convert_pixel(uint32_t pixel) {
115    switch(OUT_CFG) {
116        case SkCanvas::kNative_Premul_Config8888:
117            return convert_pixel<true,  SK_NATIVE_A_IDX,  SK_NATIVE_R_IDX, SK_NATIVE_G_IDX, SK_NATIVE_B_IDX, IN_CFG>(pixel);
118            break;
119        case SkCanvas::kNative_Unpremul_Config8888:
120            return convert_pixel<false,  SK_NATIVE_A_IDX,  SK_NATIVE_R_IDX, SK_NATIVE_G_IDX, SK_NATIVE_B_IDX, IN_CFG>(pixel);
121            break;
122        case SkCanvas::kBGRA_Premul_Config8888:
123            return convert_pixel<true, 3, 2, 1, 0, IN_CFG>(pixel);
124            break;
125        case SkCanvas::kBGRA_Unpremul_Config8888:
126            return convert_pixel<false, 3, 2, 1, 0, IN_CFG>(pixel);
127            break;
128        case SkCanvas::kRGBA_Premul_Config8888:
129            return convert_pixel<true, 3, 0, 1, 2, IN_CFG>(pixel);
130            break;
131        case SkCanvas::kRGBA_Unpremul_Config8888:
132            return convert_pixel<false, 3, 0, 1, 2, IN_CFG>(pixel);
133            break;
134        default:
135            SkDEBUGFAIL("Unexpected config8888");
136            return 0;
137            break;
138    }
139}
140
141/**
142 * SkConvertConfig8888Pixels has 6 * 6 possible combinations of src and dst
143 * configs. Each is implemented as an instantiation templated function. Two
144 * levels of switch statements are used to select the correct instantiation, one
145 * for the src config and one for the dst config.
146 */
147
148template <SkCanvas::Config8888 DST_CFG, SkCanvas::Config8888 SRC_CFG>
149inline void convert_config8888(uint32_t* dstPixels,
150                               size_t dstRowBytes,
151                               const uint32_t* srcPixels,
152                               size_t srcRowBytes,
153                               int width,
154                               int height) {
155    intptr_t dstPix = reinterpret_cast<intptr_t>(dstPixels);
156    intptr_t srcPix = reinterpret_cast<intptr_t>(srcPixels);
157
158    for (int y = 0; y < height; ++y) {
159        srcPixels = reinterpret_cast<const uint32_t*>(srcPix);
160        dstPixels = reinterpret_cast<uint32_t*>(dstPix);
161        for (int x = 0; x < width; ++x) {
162            dstPixels[x] = convert_pixel<DST_CFG, SRC_CFG>(srcPixels[x]);
163        }
164        dstPix += dstRowBytes;
165        srcPix += srcRowBytes;
166    }
167}
168
169template <SkCanvas::Config8888 SRC_CFG>
170inline void convert_config8888(uint32_t* dstPixels,
171                               size_t dstRowBytes,
172                               SkCanvas::Config8888 dstConfig,
173                               const uint32_t* srcPixels,
174                               size_t srcRowBytes,
175                               int width,
176                               int height) {
177    switch(dstConfig) {
178        case SkCanvas::kNative_Premul_Config8888:
179            convert_config8888<SkCanvas::kNative_Premul_Config8888, SRC_CFG>(dstPixels, dstRowBytes, srcPixels, srcRowBytes, width, height);
180            break;
181        case SkCanvas::kNative_Unpremul_Config8888:
182            convert_config8888<SkCanvas::kNative_Unpremul_Config8888, SRC_CFG>(dstPixels, dstRowBytes, srcPixels, srcRowBytes, width, height);
183            break;
184        case SkCanvas::kBGRA_Premul_Config8888:
185            convert_config8888<SkCanvas::kBGRA_Premul_Config8888, SRC_CFG>(dstPixels, dstRowBytes, srcPixels, srcRowBytes, width, height);
186            break;
187        case SkCanvas::kBGRA_Unpremul_Config8888:
188            convert_config8888<SkCanvas::kBGRA_Unpremul_Config8888, SRC_CFG>(dstPixels, dstRowBytes, srcPixels, srcRowBytes, width, height);
189            break;
190        case SkCanvas::kRGBA_Premul_Config8888:
191            convert_config8888<SkCanvas::kRGBA_Premul_Config8888, SRC_CFG>(dstPixels, dstRowBytes, srcPixels, srcRowBytes, width, height);
192            break;
193        case SkCanvas::kRGBA_Unpremul_Config8888:
194            convert_config8888<SkCanvas::kRGBA_Unpremul_Config8888, SRC_CFG>(dstPixels, dstRowBytes, srcPixels, srcRowBytes, width, height);
195            break;
196        default:
197            SkDEBUGFAIL("Unexpected config8888");
198            break;
199    }
200}
201
202}
203
204void SkConvertConfig8888Pixels(uint32_t* dstPixels,
205                               size_t dstRowBytes,
206                               SkCanvas::Config8888 dstConfig,
207                               const uint32_t* srcPixels,
208                               size_t srcRowBytes,
209                               SkCanvas::Config8888 srcConfig,
210                               int width,
211                               int height) {
212    if (srcConfig == dstConfig) {
213        if (srcPixels == dstPixels) {
214            return;
215        }
216        if (dstRowBytes == srcRowBytes &&
217            4U * width == srcRowBytes) {
218            memcpy(dstPixels, srcPixels, srcRowBytes * height);
219            return;
220        } else {
221            intptr_t srcPix = reinterpret_cast<intptr_t>(srcPixels);
222            intptr_t dstPix = reinterpret_cast<intptr_t>(dstPixels);
223            for (int y = 0; y < height; ++y) {
224                srcPixels = reinterpret_cast<const uint32_t*>(srcPix);
225                dstPixels = reinterpret_cast<uint32_t*>(dstPix);
226                memcpy(dstPixels, srcPixels, 4 * width);
227                srcPix += srcRowBytes;
228                dstPix += dstRowBytes;
229            }
230            return;
231        }
232    }
233    switch(srcConfig) {
234        case SkCanvas::kNative_Premul_Config8888:
235            convert_config8888<SkCanvas::kNative_Premul_Config8888>(dstPixels, dstRowBytes, dstConfig, srcPixels, srcRowBytes, width, height);
236            break;
237        case SkCanvas::kNative_Unpremul_Config8888:
238            convert_config8888<SkCanvas::kNative_Unpremul_Config8888>(dstPixels, dstRowBytes, dstConfig, srcPixels, srcRowBytes, width, height);
239            break;
240        case SkCanvas::kBGRA_Premul_Config8888:
241            convert_config8888<SkCanvas::kBGRA_Premul_Config8888>(dstPixels, dstRowBytes, dstConfig, srcPixels, srcRowBytes, width, height);
242            break;
243        case SkCanvas::kBGRA_Unpremul_Config8888:
244            convert_config8888<SkCanvas::kBGRA_Unpremul_Config8888>(dstPixels, dstRowBytes, dstConfig, srcPixels, srcRowBytes, width, height);
245            break;
246        case SkCanvas::kRGBA_Premul_Config8888:
247            convert_config8888<SkCanvas::kRGBA_Premul_Config8888>(dstPixels, dstRowBytes, dstConfig, srcPixels, srcRowBytes, width, height);
248            break;
249        case SkCanvas::kRGBA_Unpremul_Config8888:
250            convert_config8888<SkCanvas::kRGBA_Unpremul_Config8888>(dstPixels, dstRowBytes, dstConfig, srcPixels, srcRowBytes, width, height);
251            break;
252        default:
253            SkDEBUGFAIL("Unexpected config8888");
254            break;
255    }
256}
257
258uint32_t SkPackConfig8888(SkCanvas::Config8888 config,
259                          uint32_t a,
260                          uint32_t r,
261                          uint32_t g,
262                          uint32_t b) {
263    switch (config) {
264        case SkCanvas::kNative_Premul_Config8888:
265        case SkCanvas::kNative_Unpremul_Config8888:
266            return pack_config8888<SK_NATIVE_A_IDX,
267                                   SK_NATIVE_R_IDX,
268                                   SK_NATIVE_G_IDX,
269                                   SK_NATIVE_B_IDX>(a, r, g, b);
270        case SkCanvas::kBGRA_Premul_Config8888:
271        case SkCanvas::kBGRA_Unpremul_Config8888:
272            return pack_config8888<3, 2, 1, 0>(a, r, g, b);
273        case SkCanvas::kRGBA_Premul_Config8888:
274        case SkCanvas::kRGBA_Unpremul_Config8888:
275            return pack_config8888<3, 0, 1, 2>(a, r, g, b);
276        default:
277            SkDEBUGFAIL("Unexpected config8888");
278            return 0;
279    }
280}
281