michael@0: #include "SkConfig8888.h"
michael@0: #include "SkMathPriv.h"
michael@0: #include "SkUnPreMultiply.h"
michael@0: 
michael@0: namespace {
michael@0: 
michael@0: template <int A_IDX, int R_IDX, int G_IDX, int B_IDX>
michael@0: inline uint32_t pack_config8888(uint32_t a, uint32_t r,
michael@0:                                 uint32_t g, uint32_t b) {
michael@0: #ifdef SK_CPU_LENDIAN
michael@0:     return (a << (A_IDX * 8)) | (r << (R_IDX * 8)) |
michael@0:            (g << (G_IDX * 8)) | (b << (B_IDX * 8));
michael@0: #else
michael@0:     return (a << ((3-A_IDX) * 8)) | (r << ((3-R_IDX) * 8)) |
michael@0:            (g << ((3-G_IDX) * 8)) | (b << ((3-B_IDX) * 8));
michael@0: #endif
michael@0: }
michael@0: 
michael@0: template <int A_IDX, int R_IDX, int G_IDX, int B_IDX>
michael@0: inline void unpack_config8888(uint32_t color,
michael@0:                               uint32_t* a, uint32_t* r,
michael@0:                               uint32_t* g, uint32_t* b) {
michael@0: #ifdef SK_CPU_LENDIAN
michael@0:     *a = (color >> (A_IDX * 8)) & 0xff;
michael@0:     *r = (color >> (R_IDX * 8)) & 0xff;
michael@0:     *g = (color >> (G_IDX * 8)) & 0xff;
michael@0:     *b = (color >> (B_IDX * 8)) & 0xff;
michael@0: #else
michael@0:     *a = (color >> ((3 - A_IDX) * 8)) & 0xff;
michael@0:     *r = (color >> ((3 - R_IDX) * 8)) & 0xff;
michael@0:     *g = (color >> ((3 - G_IDX) * 8)) & 0xff;
michael@0:     *b = (color >> ((3 - B_IDX) * 8)) & 0xff;
michael@0: #endif
michael@0: }
michael@0: 
michael@0: #ifdef SK_CPU_LENDIAN
michael@0:     static const int SK_NATIVE_A_IDX = SK_A32_SHIFT / 8;
michael@0:     static const int SK_NATIVE_R_IDX = SK_R32_SHIFT / 8;
michael@0:     static const int SK_NATIVE_G_IDX = SK_G32_SHIFT / 8;
michael@0:     static const int SK_NATIVE_B_IDX = SK_B32_SHIFT / 8;
michael@0: #else
michael@0:     static const int SK_NATIVE_A_IDX = 3 - (SK_A32_SHIFT / 8);
michael@0:     static const int SK_NATIVE_R_IDX = 3 - (SK_R32_SHIFT / 8);
michael@0:     static const int SK_NATIVE_G_IDX = 3 - (SK_G32_SHIFT / 8);
michael@0:     static const int SK_NATIVE_B_IDX = 3 - (SK_B32_SHIFT / 8);
michael@0: #endif
michael@0: 
michael@0: /**
michael@0:  * convert_pixel<OUT_CFG, IN_CFG converts a pixel value from one Config8888 to
michael@0:  * another. It is implemented by first expanding OUT_CFG to r, g, b, a indices
michael@0:  * and an is_premul bool as params to another template function. Then IN_CFG is
michael@0:  * expanded via another function call.
michael@0:  */
michael@0: 
michael@0: template <bool OUT_PM, int OUT_A_IDX, int OUT_R_IDX, int OUT_G_IDX, int OUT_B_IDX,
michael@0:           bool IN_PM,  int IN_A_IDX,  int IN_R_IDX,  int IN_G_IDX,  int IN_B_IDX>
michael@0: inline uint32_t convert_pixel(uint32_t pixel) {
michael@0:     uint32_t a, r, g, b;
michael@0:     unpack_config8888<IN_A_IDX, IN_R_IDX, IN_G_IDX, IN_B_IDX>(pixel, &a, &r, &g, &b);
michael@0:     if (IN_PM && !OUT_PM) {
michael@0:         // Using SkUnPreMultiply::ApplyScale is faster than (value * 0xff) / a.
michael@0:         if (a) {
michael@0:             SkUnPreMultiply::Scale scale = SkUnPreMultiply::GetScale(a);
michael@0:             r = SkUnPreMultiply::ApplyScale(scale, r);
michael@0:             g = SkUnPreMultiply::ApplyScale(scale, g);
michael@0:             b = SkUnPreMultiply::ApplyScale(scale, b);
michael@0:         } else {
michael@0:             return 0;
michael@0:         }
michael@0:     } else if (!IN_PM && OUT_PM) {
michael@0:         // This matches SkUnPreMultiply conversion which we are replacing.
michael@0:         r = SkMulDiv255Round(r, a);
michael@0:         g = SkMulDiv255Round(g, a);
michael@0:         b = SkMulDiv255Round(b, a);
michael@0:     }
michael@0:     return pack_config8888<OUT_A_IDX, OUT_R_IDX, OUT_G_IDX, OUT_B_IDX>(a, r, g, b);
michael@0: }
michael@0: 
michael@0: template <bool OUT_PM, int OUT_A_IDX, int OUT_R_IDX, int OUT_G_IDX, int OUT_B_IDX, SkCanvas::Config8888 IN_CFG>
michael@0: inline uint32_t convert_pixel(uint32_t pixel) {
michael@0:     switch(IN_CFG) {
michael@0:         case SkCanvas::kNative_Premul_Config8888:
michael@0:             return convert_pixel<OUT_PM, OUT_A_IDX,       OUT_R_IDX,       OUT_G_IDX,       OUT_B_IDX,
michael@0:                                  true,  SK_NATIVE_A_IDX,  SK_NATIVE_R_IDX, SK_NATIVE_G_IDX, SK_NATIVE_B_IDX>(pixel);
michael@0:             break;
michael@0:         case SkCanvas::kNative_Unpremul_Config8888:
michael@0:             return convert_pixel<OUT_PM, OUT_A_IDX,       OUT_R_IDX,       OUT_G_IDX,       OUT_B_IDX,
michael@0:                                  false,  SK_NATIVE_A_IDX, SK_NATIVE_R_IDX, SK_NATIVE_G_IDX, SK_NATIVE_B_IDX>(pixel);
michael@0:             break;
michael@0:         case SkCanvas::kBGRA_Premul_Config8888:
michael@0:             return convert_pixel<OUT_PM, OUT_A_IDX, OUT_R_IDX, OUT_G_IDX, OUT_B_IDX,
michael@0:                                  true,  3,         2,         1,         0>(pixel);
michael@0:             break;
michael@0:         case SkCanvas::kBGRA_Unpremul_Config8888:
michael@0:             return convert_pixel<OUT_PM, OUT_A_IDX, OUT_R_IDX, OUT_G_IDX, OUT_B_IDX,
michael@0:                                  false,  3,         2,         1,         0>(pixel);
michael@0:             break;
michael@0:         case SkCanvas::kRGBA_Premul_Config8888:
michael@0:             return convert_pixel<OUT_PM, OUT_A_IDX, OUT_R_IDX, OUT_G_IDX, OUT_B_IDX,
michael@0:                                  true,  3,         0,         1,         2>(pixel);
michael@0:             break;
michael@0:         case SkCanvas::kRGBA_Unpremul_Config8888:
michael@0:             return convert_pixel<OUT_PM, OUT_A_IDX, OUT_R_IDX, OUT_G_IDX, OUT_B_IDX,
michael@0:                                  false,  3,         0,         1,         2>(pixel);
michael@0:             break;
michael@0:         default:
michael@0:             SkDEBUGFAIL("Unexpected config8888");
michael@0:             return 0;
michael@0:             break;
michael@0:     }
michael@0: }
michael@0: 
michael@0: template <SkCanvas::Config8888 OUT_CFG, SkCanvas::Config8888 IN_CFG>
michael@0: inline uint32_t convert_pixel(uint32_t pixel) {
michael@0:     switch(OUT_CFG) {
michael@0:         case SkCanvas::kNative_Premul_Config8888:
michael@0:             return convert_pixel<true,  SK_NATIVE_A_IDX,  SK_NATIVE_R_IDX, SK_NATIVE_G_IDX, SK_NATIVE_B_IDX, IN_CFG>(pixel);
michael@0:             break;
michael@0:         case SkCanvas::kNative_Unpremul_Config8888:
michael@0:             return convert_pixel<false,  SK_NATIVE_A_IDX,  SK_NATIVE_R_IDX, SK_NATIVE_G_IDX, SK_NATIVE_B_IDX, IN_CFG>(pixel);
michael@0:             break;
michael@0:         case SkCanvas::kBGRA_Premul_Config8888:
michael@0:             return convert_pixel<true, 3, 2, 1, 0, IN_CFG>(pixel);
michael@0:             break;
michael@0:         case SkCanvas::kBGRA_Unpremul_Config8888:
michael@0:             return convert_pixel<false, 3, 2, 1, 0, IN_CFG>(pixel);
michael@0:             break;
michael@0:         case SkCanvas::kRGBA_Premul_Config8888:
michael@0:             return convert_pixel<true, 3, 0, 1, 2, IN_CFG>(pixel);
michael@0:             break;
michael@0:         case SkCanvas::kRGBA_Unpremul_Config8888:
michael@0:             return convert_pixel<false, 3, 0, 1, 2, IN_CFG>(pixel);
michael@0:             break;
michael@0:         default:
michael@0:             SkDEBUGFAIL("Unexpected config8888");
michael@0:             return 0;
michael@0:             break;
michael@0:     }
michael@0: }
michael@0: 
michael@0: /**
michael@0:  * SkConvertConfig8888Pixels has 6 * 6 possible combinations of src and dst
michael@0:  * configs. Each is implemented as an instantiation templated function. Two
michael@0:  * levels of switch statements are used to select the correct instantiation, one
michael@0:  * for the src config and one for the dst config.
michael@0:  */
michael@0: 
michael@0: template <SkCanvas::Config8888 DST_CFG, SkCanvas::Config8888 SRC_CFG>
michael@0: inline void convert_config8888(uint32_t* dstPixels,
michael@0:                                size_t dstRowBytes,
michael@0:                                const uint32_t* srcPixels,
michael@0:                                size_t srcRowBytes,
michael@0:                                int width,
michael@0:                                int height) {
michael@0:     intptr_t dstPix = reinterpret_cast<intptr_t>(dstPixels);
michael@0:     intptr_t srcPix = reinterpret_cast<intptr_t>(srcPixels);
michael@0: 
michael@0:     for (int y = 0; y < height; ++y) {
michael@0:         srcPixels = reinterpret_cast<const uint32_t*>(srcPix);
michael@0:         dstPixels = reinterpret_cast<uint32_t*>(dstPix);
michael@0:         for (int x = 0; x < width; ++x) {
michael@0:             dstPixels[x] = convert_pixel<DST_CFG, SRC_CFG>(srcPixels[x]);
michael@0:         }
michael@0:         dstPix += dstRowBytes;
michael@0:         srcPix += srcRowBytes;
michael@0:     }
michael@0: }
michael@0: 
michael@0: template <SkCanvas::Config8888 SRC_CFG>
michael@0: inline void convert_config8888(uint32_t* dstPixels,
michael@0:                                size_t dstRowBytes,
michael@0:                                SkCanvas::Config8888 dstConfig,
michael@0:                                const uint32_t* srcPixels,
michael@0:                                size_t srcRowBytes,
michael@0:                                int width,
michael@0:                                int height) {
michael@0:     switch(dstConfig) {
michael@0:         case SkCanvas::kNative_Premul_Config8888:
michael@0:             convert_config8888<SkCanvas::kNative_Premul_Config8888, SRC_CFG>(dstPixels, dstRowBytes, srcPixels, srcRowBytes, width, height);
michael@0:             break;
michael@0:         case SkCanvas::kNative_Unpremul_Config8888:
michael@0:             convert_config8888<SkCanvas::kNative_Unpremul_Config8888, SRC_CFG>(dstPixels, dstRowBytes, srcPixels, srcRowBytes, width, height);
michael@0:             break;
michael@0:         case SkCanvas::kBGRA_Premul_Config8888:
michael@0:             convert_config8888<SkCanvas::kBGRA_Premul_Config8888, SRC_CFG>(dstPixels, dstRowBytes, srcPixels, srcRowBytes, width, height);
michael@0:             break;
michael@0:         case SkCanvas::kBGRA_Unpremul_Config8888:
michael@0:             convert_config8888<SkCanvas::kBGRA_Unpremul_Config8888, SRC_CFG>(dstPixels, dstRowBytes, srcPixels, srcRowBytes, width, height);
michael@0:             break;
michael@0:         case SkCanvas::kRGBA_Premul_Config8888:
michael@0:             convert_config8888<SkCanvas::kRGBA_Premul_Config8888, SRC_CFG>(dstPixels, dstRowBytes, srcPixels, srcRowBytes, width, height);
michael@0:             break;
michael@0:         case SkCanvas::kRGBA_Unpremul_Config8888:
michael@0:             convert_config8888<SkCanvas::kRGBA_Unpremul_Config8888, SRC_CFG>(dstPixels, dstRowBytes, srcPixels, srcRowBytes, width, height);
michael@0:             break;
michael@0:         default:
michael@0:             SkDEBUGFAIL("Unexpected config8888");
michael@0:             break;
michael@0:     }
michael@0: }
michael@0: 
michael@0: }
michael@0: 
michael@0: void SkConvertConfig8888Pixels(uint32_t* dstPixels,
michael@0:                                size_t dstRowBytes,
michael@0:                                SkCanvas::Config8888 dstConfig,
michael@0:                                const uint32_t* srcPixels,
michael@0:                                size_t srcRowBytes,
michael@0:                                SkCanvas::Config8888 srcConfig,
michael@0:                                int width,
michael@0:                                int height) {
michael@0:     if (srcConfig == dstConfig) {
michael@0:         if (srcPixels == dstPixels) {
michael@0:             return;
michael@0:         }
michael@0:         if (dstRowBytes == srcRowBytes &&
michael@0:             4U * width == srcRowBytes) {
michael@0:             memcpy(dstPixels, srcPixels, srcRowBytes * height);
michael@0:             return;
michael@0:         } else {
michael@0:             intptr_t srcPix = reinterpret_cast<intptr_t>(srcPixels);
michael@0:             intptr_t dstPix = reinterpret_cast<intptr_t>(dstPixels);
michael@0:             for (int y = 0; y < height; ++y) {
michael@0:                 srcPixels = reinterpret_cast<const uint32_t*>(srcPix);
michael@0:                 dstPixels = reinterpret_cast<uint32_t*>(dstPix);
michael@0:                 memcpy(dstPixels, srcPixels, 4 * width);
michael@0:                 srcPix += srcRowBytes;
michael@0:                 dstPix += dstRowBytes;
michael@0:             }
michael@0:             return;
michael@0:         }
michael@0:     }
michael@0:     switch(srcConfig) {
michael@0:         case SkCanvas::kNative_Premul_Config8888:
michael@0:             convert_config8888<SkCanvas::kNative_Premul_Config8888>(dstPixels, dstRowBytes, dstConfig, srcPixels, srcRowBytes, width, height);
michael@0:             break;
michael@0:         case SkCanvas::kNative_Unpremul_Config8888:
michael@0:             convert_config8888<SkCanvas::kNative_Unpremul_Config8888>(dstPixels, dstRowBytes, dstConfig, srcPixels, srcRowBytes, width, height);
michael@0:             break;
michael@0:         case SkCanvas::kBGRA_Premul_Config8888:
michael@0:             convert_config8888<SkCanvas::kBGRA_Premul_Config8888>(dstPixels, dstRowBytes, dstConfig, srcPixels, srcRowBytes, width, height);
michael@0:             break;
michael@0:         case SkCanvas::kBGRA_Unpremul_Config8888:
michael@0:             convert_config8888<SkCanvas::kBGRA_Unpremul_Config8888>(dstPixels, dstRowBytes, dstConfig, srcPixels, srcRowBytes, width, height);
michael@0:             break;
michael@0:         case SkCanvas::kRGBA_Premul_Config8888:
michael@0:             convert_config8888<SkCanvas::kRGBA_Premul_Config8888>(dstPixels, dstRowBytes, dstConfig, srcPixels, srcRowBytes, width, height);
michael@0:             break;
michael@0:         case SkCanvas::kRGBA_Unpremul_Config8888:
michael@0:             convert_config8888<SkCanvas::kRGBA_Unpremul_Config8888>(dstPixels, dstRowBytes, dstConfig, srcPixels, srcRowBytes, width, height);
michael@0:             break;
michael@0:         default:
michael@0:             SkDEBUGFAIL("Unexpected config8888");
michael@0:             break;
michael@0:     }
michael@0: }
michael@0: 
michael@0: uint32_t SkPackConfig8888(SkCanvas::Config8888 config,
michael@0:                           uint32_t a,
michael@0:                           uint32_t r,
michael@0:                           uint32_t g,
michael@0:                           uint32_t b) {
michael@0:     switch (config) {
michael@0:         case SkCanvas::kNative_Premul_Config8888:
michael@0:         case SkCanvas::kNative_Unpremul_Config8888:
michael@0:             return pack_config8888<SK_NATIVE_A_IDX,
michael@0:                                    SK_NATIVE_R_IDX,
michael@0:                                    SK_NATIVE_G_IDX,
michael@0:                                    SK_NATIVE_B_IDX>(a, r, g, b);
michael@0:         case SkCanvas::kBGRA_Premul_Config8888:
michael@0:         case SkCanvas::kBGRA_Unpremul_Config8888:
michael@0:             return pack_config8888<3, 2, 1, 0>(a, r, g, b);
michael@0:         case SkCanvas::kRGBA_Premul_Config8888:
michael@0:         case SkCanvas::kRGBA_Unpremul_Config8888:
michael@0:             return pack_config8888<3, 0, 1, 2>(a, r, g, b);
michael@0:         default:
michael@0:             SkDEBUGFAIL("Unexpected config8888");
michael@0:             return 0;
michael@0:     }
michael@0: }