| /* |
| * Copyright 2014 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "SkBitmap.h" |
| #include "SkCanvas.h" |
| #include "SkConfig8888.h" |
| #include "SkColorPriv.h" |
| #include "SkDither.h" |
| #include "SkMathPriv.h" |
| #include "SkUnPreMultiply.h" |
| |
| enum AlphaVerb { |
| kNothing_AlphaVerb, |
| kPremul_AlphaVerb, |
| kUnpremul_AlphaVerb, |
| }; |
| |
| template <bool doSwapRB, AlphaVerb doAlpha> uint32_t convert32(uint32_t c) { |
| if (doSwapRB) { |
| c = SkSwizzle_RB(c); |
| } |
| |
| // Lucky for us, in both RGBA and BGRA, the alpha component is always in the same place, so |
| // we can perform premul or unpremul the same way without knowing the swizzles for RGB. |
| switch (doAlpha) { |
| case kNothing_AlphaVerb: |
| // no change |
| break; |
| case kPremul_AlphaVerb: |
| c = SkPreMultiplyARGB(SkGetPackedA32(c), SkGetPackedR32(c), |
| SkGetPackedG32(c), SkGetPackedB32(c)); |
| break; |
| case kUnpremul_AlphaVerb: |
| c = SkUnPreMultiply::UnPreMultiplyPreservingByteOrder(c); |
| break; |
| } |
| return c; |
| } |
| |
| template <bool doSwapRB, AlphaVerb doAlpha> |
| void convert32_row(uint32_t* dst, const uint32_t* src, int count) { |
| // This has to be correct if src == dst (but not partial overlap) |
| for (int i = 0; i < count; ++i) { |
| dst[i] = convert32<doSwapRB, doAlpha>(src[i]); |
| } |
| } |
| |
| static bool is_32bit_colortype(SkColorType ct) { |
| return kRGBA_8888_SkColorType == ct || kBGRA_8888_SkColorType == ct; |
| } |
| |
| static AlphaVerb compute_AlphaVerb(SkAlphaType src, SkAlphaType dst) { |
| SkASSERT(kIgnore_SkAlphaType != src); |
| SkASSERT(kIgnore_SkAlphaType != dst); |
| |
| if (kOpaque_SkAlphaType == src || kOpaque_SkAlphaType == dst || src == dst) { |
| return kNothing_AlphaVerb; |
| } |
| if (kPremul_SkAlphaType == dst) { |
| SkASSERT(kUnpremul_SkAlphaType == src); |
| return kPremul_AlphaVerb; |
| } else { |
| SkASSERT(kPremul_SkAlphaType == src); |
| SkASSERT(kUnpremul_SkAlphaType == dst); |
| return kUnpremul_AlphaVerb; |
| } |
| } |
| |
| static void memcpy32_row(uint32_t* dst, const uint32_t* src, int count) { |
| memcpy(dst, src, count * 4); |
| } |
| |
| bool SkSrcPixelInfo::convertPixelsTo(SkDstPixelInfo* dst, int width, int height) const { |
| if (width <= 0 || height <= 0) { |
| return false; |
| } |
| |
| if (!is_32bit_colortype(fColorType) || !is_32bit_colortype(dst->fColorType)) { |
| return false; |
| } |
| |
| void (*proc)(uint32_t* dst, const uint32_t* src, int count); |
| AlphaVerb doAlpha = compute_AlphaVerb(fAlphaType, dst->fAlphaType); |
| bool doSwapRB = fColorType != dst->fColorType; |
| |
| switch (doAlpha) { |
| case kNothing_AlphaVerb: |
| if (doSwapRB) { |
| proc = convert32_row<true, kNothing_AlphaVerb>; |
| } else { |
| if (fPixels == dst->fPixels) { |
| return true; |
| } |
| proc = memcpy32_row; |
| } |
| break; |
| case kPremul_AlphaVerb: |
| if (doSwapRB) { |
| proc = convert32_row<true, kPremul_AlphaVerb>; |
| } else { |
| proc = convert32_row<false, kPremul_AlphaVerb>; |
| } |
| break; |
| case kUnpremul_AlphaVerb: |
| if (doSwapRB) { |
| proc = convert32_row<true, kUnpremul_AlphaVerb>; |
| } else { |
| proc = convert32_row<false, kUnpremul_AlphaVerb>; |
| } |
| break; |
| } |
| |
| uint32_t* dstP = static_cast<uint32_t*>(dst->fPixels); |
| const uint32_t* srcP = static_cast<const uint32_t*>(fPixels); |
| size_t srcInc = fRowBytes >> 2; |
| size_t dstInc = dst->fRowBytes >> 2; |
| for (int y = 0; y < height; ++y) { |
| proc(dstP, srcP, width); |
| dstP += dstInc; |
| srcP += srcInc; |
| } |
| return true; |
| } |
| |
| static void rect_memcpy(void* dst, size_t dstRB, const void* src, size_t srcRB, size_t bytesPerRow, |
| int rowCount) { |
| SkASSERT(bytesPerRow <= srcRB); |
| SkASSERT(bytesPerRow <= dstRB); |
| for (int i = 0; i < rowCount; ++i) { |
| memcpy(dst, src, bytesPerRow); |
| dst = (char*)dst + dstRB; |
| src = (const char*)src + srcRB; |
| } |
| } |
| |
| bool SkPixelInfo::CopyPixels(const SkImageInfo& dstInfo, void* dstPixels, size_t dstRB, |
| const SkImageInfo& srcInfo, const void* srcPixels, size_t srcRB, |
| SkColorTable* ctable) { |
| if (srcInfo.dimensions() != dstInfo.dimensions()) { |
| return false; |
| } |
| |
| const int width = srcInfo.width(); |
| const int height = srcInfo.height(); |
| |
| // Handle fancy alpha swizzling if both are ARGB32 |
| if (4 == srcInfo.bytesPerPixel() && 4 == dstInfo.bytesPerPixel()) { |
| SkDstPixelInfo dstPI; |
| dstPI.fColorType = dstInfo.colorType(); |
| dstPI.fAlphaType = dstInfo.alphaType(); |
| dstPI.fPixels = dstPixels; |
| dstPI.fRowBytes = dstRB; |
| |
| SkSrcPixelInfo srcPI; |
| srcPI.fColorType = srcInfo.colorType(); |
| srcPI.fAlphaType = srcInfo.alphaType(); |
| srcPI.fPixels = srcPixels; |
| srcPI.fRowBytes = srcRB; |
| |
| return srcPI.convertPixelsTo(&dstPI, width, height); |
| } |
| |
| // If they agree on colorType and the alphaTypes are compatible, then we just memcpy. |
| // Note: we've already taken care of 32bit colortypes above. |
| if (srcInfo.colorType() == dstInfo.colorType()) { |
| switch (srcInfo.colorType()) { |
| case kRGB_565_SkColorType: |
| case kAlpha_8_SkColorType: |
| break; |
| case kIndex_8_SkColorType: |
| case kARGB_4444_SkColorType: |
| if (srcInfo.alphaType() != dstInfo.alphaType()) { |
| return false; |
| } |
| break; |
| default: |
| return false; |
| } |
| rect_memcpy(dstPixels, dstRB, srcPixels, srcRB, width * srcInfo.bytesPerPixel(), height); |
| return true; |
| } |
| |
| /* |
| * Begin section where we try to change colorTypes along the way. Not all combinations |
| * are supported. |
| */ |
| |
| // Can no longer draw directly into 4444, but we can manually whack it for a few combinations |
| if (kARGB_4444_SkColorType == dstInfo.colorType() && |
| (kN32_SkColorType == srcInfo.colorType() || kIndex_8_SkColorType == srcInfo.colorType())) { |
| if (srcInfo.alphaType() == kUnpremul_SkAlphaType) { |
| // Our method for converting to 4444 assumes premultiplied. |
| return false; |
| } |
| |
| const SkPMColor* table = NULL; |
| if (kIndex_8_SkColorType == srcInfo.colorType()) { |
| if (NULL == ctable) { |
| return false; |
| } |
| table = ctable->lockColors(); |
| } |
| |
| for (int y = 0; y < height; ++y) { |
| DITHER_4444_SCAN(y); |
| SkPMColor16* SK_RESTRICT dstRow = (SkPMColor16*)dstPixels; |
| if (table) { |
| const uint8_t* SK_RESTRICT srcRow = (const uint8_t*)srcPixels; |
| for (int x = 0; x < width; ++x) { |
| dstRow[x] = SkDitherARGB32To4444(table[srcRow[x]], DITHER_VALUE(x)); |
| } |
| } else { |
| const SkPMColor* SK_RESTRICT srcRow = (const SkPMColor*)srcPixels; |
| for (int x = 0; x < width; ++x) { |
| dstRow[x] = SkDitherARGB32To4444(srcRow[x], DITHER_VALUE(x)); |
| } |
| } |
| dstPixels = (char*)dstPixels + dstRB; |
| srcPixels = (const char*)srcPixels + srcRB; |
| } |
| |
| if (table) { |
| ctable->unlockColors(); |
| } |
| return true; |
| } |
| |
| if (dstInfo.alphaType() == kUnpremul_SkAlphaType) { |
| // We do not support drawing to unpremultiplied bitmaps. |
| return false; |
| } |
| |
| // Final fall-back, draw with a canvas |
| // |
| // Always clear the dest in case one of the blitters accesses it |
| // TODO: switch the allocation of tmpDst to call sk_calloc_throw |
| { |
| SkBitmap bm; |
| if (!bm.installPixels(srcInfo, const_cast<void*>(srcPixels), srcRB, ctable, NULL, NULL)) { |
| return false; |
| } |
| SkAutoTUnref<SkCanvas> canvas(SkCanvas::NewRasterDirect(dstInfo, dstPixels, dstRB)); |
| if (NULL == canvas.get()) { |
| return false; |
| } |
| |
| SkPaint paint; |
| paint.setDither(true); |
| |
| canvas->clear(0); |
| canvas->drawBitmap(bm, 0, 0, &paint); |
| return true; |
| } |
| } |
| |