Adding premul and 565 swizzles for bmp:

src/codec/SkMaskSwizzler.cpp

Index: src/codec/SkMaskSwizzler.cpp
diff --git a/src/codec/SkMaskSwizzler.cpp b/src/codec/SkMaskSwizzler.cpp
index 8d9f6c66b3ac007e955118b872d244b52614ea3b..944042d1abd1e084c8c0049e3c0060700abed843 100644
--- a/src/codec/SkMaskSwizzler.cpp
+++ b/src/codec/SkMaskSwizzler.cpp
@@ -9,12 +9,7 @@
 #include "SkColorPriv.h"
 #include "SkMaskSwizzler.h"
 
-/*
- *
- * Row procedure for masked color components with 16 bits per pixel
- *
- */
-static SkSwizzler::ResultAlpha swizzle_mask16_to_n32(
+static SkSwizzler::ResultAlpha swizzle_mask16_to_n32_opaque(
         void* dstRow, const uint8_t* srcRow, int width, SkMasks* masks) {
 
     // Use the masks to decode to the destination
@@ -30,12 +25,7 @@ static SkSwizzler::ResultAlpha swizzle_mask16_to_n32(
     return SkSwizzler::kOpaque_ResultAlpha;
 }
 
-/*
- *
- * Row procedure for masked color components with 16 bits per pixel with alpha
- *
- */
-static SkSwizzler::ResultAlpha swizzle_mask16_alpha_to_n32(
+static SkSwizzler::ResultAlpha swizzle_mask16_to_n32_unpremul(
         void* dstRow, const uint8_t* srcRow, int width, SkMasks* masks) {
 
     // Use the masks to decode to the destination
@@ -54,12 +44,42 @@ static SkSwizzler::ResultAlpha swizzle_mask16_alpha_to_n32(
     return COMPUTE_RESULT_ALPHA;
 }
 
-/*
- *
- * Row procedure for masked color components with 24 bits per pixel
- *
- */
-static SkSwizzler::ResultAlpha swizzle_mask24_to_n32(
+static SkSwizzler::ResultAlpha swizzle_mask16_to_n32_premul(
+        void* dstRow, const uint8_t* srcRow, int width, SkMasks* masks) {
+
+    // Use the masks to decode to the destination
+    uint16_t* srcPtr = (uint16_t*) srcRow;
+    SkPMColor* dstPtr = (SkPMColor*) dstRow;
+    INIT_RESULT_ALPHA;
+    for (int i = 0; i < width; i++) {
+        uint16_t p = srcPtr[i];
+        uint8_t red = masks->getRed(p);
+        uint8_t green = masks->getGreen(p);
+        uint8_t blue = masks->getBlue(p);
+        uint8_t alpha = masks->getAlpha(p);
+        UPDATE_RESULT_ALPHA(alpha);
+        dstPtr[i] = SkPreMultiplyARGB(alpha, red, green, blue);
+    }
+    return COMPUTE_RESULT_ALPHA;
+}
+
+static SkSwizzler::ResultAlpha swizzle_mask16_to_565(
+        void* dstRow, const uint8_t* srcRow, int width, SkMasks* masks) {
+
+    // Use the masks to decode to the destination
+    uint16_t* srcPtr = (uint16_t*) srcRow;
+    uint16_t* dstPtr = (uint16_t*) dstRow;
+    for (int i = 0; i < width; i++) {
+        uint16_t p = srcPtr[i];
+        uint8_t red = masks->getRed(p);
+        uint8_t green = masks->getGreen(p);
+        uint8_t blue = masks->getBlue(p);
+        dstPtr[i] = SkPack888ToRGB16(red, green, blue);
+    }
+    return SkSwizzler::kOpaque_ResultAlpha;
+}
+
+static SkSwizzler::ResultAlpha swizzle_mask24_to_n32_opaque(
         void* dstRow, const uint8_t* srcRow, int width, SkMasks* masks) {
 
     // Use the masks to decode to the destination
@@ -74,12 +94,7 @@ static SkSwizzler::ResultAlpha swizzle_mask24_to_n32(
     return SkSwizzler::kOpaque_ResultAlpha;
 }
 
-/*
- *
- * Row procedure for masked color components with 24 bits per pixel with alpha
- *
- */
-static SkSwizzler::ResultAlpha swizzle_mask24_alpha_to_n32(
+static SkSwizzler::ResultAlpha swizzle_mask24_to_n32_unpremul(
         void* dstRow, const uint8_t* srcRow, int width, SkMasks* masks) {
 
     // Use the masks to decode to the destination
@@ -97,12 +112,40 @@ static SkSwizzler::ResultAlpha swizzle_mask24_alpha_to_n32(
     return COMPUTE_RESULT_ALPHA;
 }
 
-/*
- *
- * Row procedure for masked color components with 32 bits per pixel
- *
- */
-static SkSwizzler::ResultAlpha swizzle_mask32_to_n32(
+static SkSwizzler::ResultAlpha swizzle_mask24_to_n32_premul(
+        void* dstRow, const uint8_t* srcRow, int width, SkMasks* masks) {
+
+    // Use the masks to decode to the destination
+    SkPMColor* dstPtr = (SkPMColor*) dstRow;
+    INIT_RESULT_ALPHA;
+    for (int i = 0; i < 3*width; i += 3) {
+        uint32_t p = srcRow[i] | (srcRow[i + 1] << 8) | srcRow[i + 2] << 16;
+        uint8_t red = masks->getRed(p);
+        uint8_t green = masks->getGreen(p);
+        uint8_t blue = masks->getBlue(p);
+        uint8_t alpha = masks->getAlpha(p);
+        UPDATE_RESULT_ALPHA(alpha);
+        dstPtr[i/3] = SkPreMultiplyARGB(alpha, red, green, blue);
+    }
+    return COMPUTE_RESULT_ALPHA;
+}
+
+static SkSwizzler::ResultAlpha swizzle_mask24_to_565(
+        void* dstRow, const uint8_t* srcRow, int width, SkMasks* masks) {
+
+    // Use the masks to decode to the destination
+    uint16_t* dstPtr = (uint16_t*) dstRow;
+    for (int i = 0; i < 3*width; i += 3) {
+        uint32_t p = srcRow[i] | (srcRow[i + 1] << 8) | srcRow[i + 2] << 16;
+        uint8_t red = masks->getRed(p);
+        uint8_t green = masks->getGreen(p);
+        uint8_t blue = masks->getBlue(p);
+        dstPtr[i/3] = SkPack888ToRGB16(red, green, blue);
+    }
+    return SkSwizzler::kOpaque_ResultAlpha;
+}
+
+static SkSwizzler::ResultAlpha swizzle_mask32_to_n32_opaque(
         void* dstRow, const uint8_t* srcRow, int width, SkMasks* masks) {
 
     // Use the masks to decode to the destination
@@ -118,12 +161,7 @@ static SkSwizzler::ResultAlpha swizzle_mask32_to_n32(
     return SkSwizzler::kOpaque_ResultAlpha;
 }
 
-/*
- *
- * Row procedure for masked color components with 32 bits per pixel
- *
- */
-static SkSwizzler::ResultAlpha swizzle_mask32_alpha_to_n32(
+static SkSwizzler::ResultAlpha swizzle_mask32_to_n32_unpremul(
         void* dstRow, const uint8_t* srcRow, int width, SkMasks* masks) {
 
     // Use the masks to decode to the destination
@@ -142,44 +180,148 @@ static SkSwizzler::ResultAlpha swizzle_mask32_alpha_to_n32(
     return COMPUTE_RESULT_ALPHA;
 }
 
+static SkSwizzler::ResultAlpha swizzle_mask32_to_n32_premul(
+        void* dstRow, const uint8_t* srcRow, int width, SkMasks* masks) {
+
+    // Use the masks to decode to the destination
+    uint32_t* srcPtr = (uint32_t*) srcRow;
+    SkPMColor* dstPtr = (SkPMColor*) dstRow;
+    INIT_RESULT_ALPHA;
+    for (int i = 0; i < width; i++) {
+        uint32_t p = srcPtr[i];
+        uint8_t red = masks->getRed(p);
+        uint8_t green = masks->getGreen(p);
+        uint8_t blue = masks->getBlue(p);
+        uint8_t alpha = masks->getAlpha(p);
+        UPDATE_RESULT_ALPHA(alpha);
+        dstPtr[i] = SkPreMultiplyARGB(alpha, red, green, blue);
+    }
+    return COMPUTE_RESULT_ALPHA;
+}
+
+static SkSwizzler::ResultAlpha swizzle_mask32_to_565(
+        void* dstRow, const uint8_t* srcRow, int width, SkMasks* masks) {
+
+    // Use the masks to decode to the destination
+    uint32_t* srcPtr = (uint32_t*) srcRow;
+    uint16_t* dstPtr = (uint16_t*) dstRow;
+    for (int i = 0; i < width; i++) {
+        uint32_t p = srcPtr[i];
+        uint8_t red = masks->getRed(p);
+        uint8_t green = masks->getGreen(p);
+        uint8_t blue = masks->getBlue(p);
+        dstPtr[i] = SkPack888ToRGB16(red, green, blue);
+    }
+    return SkSwizzler::kOpaque_ResultAlpha;
+}
+
 /*
  *
  * Create a new mask swizzler
  *
  */
 SkMaskSwizzler* SkMaskSwizzler::CreateMaskSwizzler(
-        const SkImageInfo& imageInfo, SkMasks* masks, uint32_t bitsPerPixel) {
+        const SkImageInfo& info, void* dst, size_t dstRowBytes, SkMasks* masks,
+        uint32_t bitsPerPixel) {
 
     // Choose the appropriate row procedure
     RowProc proc = NULL;
-    uint32_t alphaMask = masks->getAlphaMask();
     switch (bitsPerPixel) {
         case 16:
-            if (0 == alphaMask) {
-                proc = &swizzle_mask16_to_n32;
-            } else {
-                proc = &swizzle_mask16_alpha_to_n32;
+            switch (info.colorType()) {
+                case kN32_SkColorType:
+                    switch (info.alphaType()) {
+                        case kUnpremul_SkAlphaType:
+                            proc = &swizzle_mask16_to_n32_unpremul;
+                            break;
+                        case kPremul_SkAlphaType:
+                            proc = &swizzle_mask16_to_n32_premul;
+                            break;
+                        case kOpaque_SkAlphaType:
+                            proc = &swizzle_mask16_to_n32_opaque;
+                            break;
+                        default:
+                            break;
+                    }
+                    break;
+                case kRGB_565_SkColorType:
+                    switch (info.alphaType()) {
+                        case kOpaque_SkAlphaType:
+                            proc = &swizzle_mask16_to_565;
+                            break;
+                        default:
+                            break;
+                    }
+                    break;
+                default:
+                    break;
             }
             break;
         case 24:
-            if (0 == alphaMask) {
-                proc = &swizzle_mask24_to_n32;
-            } else {
-                proc = &swizzle_mask24_alpha_to_n32;
+            switch (info.colorType()) {
+                case kN32_SkColorType:
+                    switch (info.alphaType()) {
+                        case kUnpremul_SkAlphaType:
+                            proc = &swizzle_mask24_to_n32_unpremul;
+                            break;
+                        case kPremul_SkAlphaType:
+                            proc = &swizzle_mask24_to_n32_premul;
+                            break;
+                        case kOpaque_SkAlphaType:
+                            proc = &swizzle_mask24_to_n32_opaque;
+                            break;
+                        default:
+                            break;
+                    }
+                    break;
+                case kRGB_565_SkColorType:
+                    switch (info.alphaType()) {
+                        case kOpaque_SkAlphaType:
+                            proc = &swizzle_mask24_to_565;
+                            break;
+                        default:
+                            break;
+                    }
+                    break;
+                default:
+                    break;
             }
             break;
         case 32:
-            if (0 == alphaMask) {
-                proc = &swizzle_mask32_to_n32;
-            } else {
-                proc = &swizzle_mask32_alpha_to_n32;
+            switch (info.colorType()) {
+                case kN32_SkColorType:
+                    switch (info.alphaType()) {
+                        case kUnpremul_SkAlphaType:
+                            proc = &swizzle_mask32_to_n32_unpremul;
+                            break;
+                        case kPremul_SkAlphaType:
+                            proc = &swizzle_mask32_to_n32_premul;
+                            break;
+                        case kOpaque_SkAlphaType:
+                            proc = &swizzle_mask32_to_n32_opaque;
+                            break;
+                        default:
+                            break;
+                    }
+                    break;
+                case kRGB_565_SkColorType:
+                    switch (info.alphaType()) {
+                        case kOpaque_SkAlphaType:
+                            proc = &swizzle_mask32_to_565;
+                            break;
+                        default:
+                            break;
+                    }
+                    break;
+                default:
+                    break;
             }
             break;
         default:
             SkASSERT(false);
             return NULL;
     }
-    return SkNEW_ARGS(SkMaskSwizzler, (imageInfo, masks, proc));
+    return SkNEW_ARGS(SkMaskSwizzler, (info, dst, dstRowBytes, masks, proc));
 }
 
 /*
@@ -187,19 +329,25 @@ SkMaskSwizzler* SkMaskSwizzler::CreateMaskSwizzler(
  * Constructor for mask swizzler
  *
  */
-SkMaskSwizzler::SkMaskSwizzler(const SkImageInfo& imageInfo,
-                               SkMasks* masks, RowProc proc)
-    : fImageInfo(imageInfo)
+SkMaskSwizzler::SkMaskSwizzler(const SkImageInfo& dstInfo, void* dst,
+                               size_t dstRowBytes, SkMasks* masks, RowProc proc)
+    : fDstInfo(dstInfo)
+    , fDst(dst)
+    , fDstRowBytes(dstRowBytes)
     , fMasks(masks)
     , fRowProc(proc)
 {}
 
 /*
  *
- * Swizzle the next row
+ * Swizzle the specified row
  *
  */
-SkSwizzler::ResultAlpha SkMaskSwizzler::next(void* dst,
-                                             const uint8_t* src) {
-    return fRowProc(dst, src, fImageInfo.width(), fMasks);
+SkSwizzler::ResultAlpha SkMaskSwizzler::next(const uint8_t* SK_RESTRICT src,
+        int y) {
+    // Choose the row
+    void* row = SkTAddOffset<void>(fDst, y*fDstRowBytes);
+
+    // Decode the row
+    return fRowProc(row, src, fDstInfo.width(), fMasks);
 }