Revert[8] "replace SkXfermode obj with SkBlendMode enum in paints"

src/core/SkBlitter_RGB16.cpp

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBlitRow.h"
 #include "SkCoreBlitters.h"
 #include "SkColorPriv.h"
@@ skipping 142 matching lines @@
 
     typedef SkShaderBlitter INHERITED;
 };
 
 ///////////////////////////////////////////////////////////////////////////////
 #ifdef USE_BLACK_BLITTER
 SkRGB16_Black_Blitter::SkRGB16_Black_Blitter(const SkPixmap& device, const SkPaint& paint)
     : INHERITED(device, paint) {
     SkASSERT(paint.getShader() == nullptr);
     SkASSERT(paint.getColorFilter() == nullptr);
-    SkASSERT(paint.getXfermode() == nullptr);
+    SkASSERT(paint.isSrcOver());
     SkASSERT(paint.getColor() == SK_ColorBLACK);
 }
 
 #if 1
 #define black_8_pixels(mask, dst)       \
     do {                                \
         if (mask & 0x80) dst[0] = 0;    \
         if (mask & 0x40) dst[1] = 0;    \
         if (mask & 0x20) dst[2] = 0;    \
         if (mask & 0x10) dst[3] = 0;    \
@@ skipping 502 matching lines @@
     }
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 SkRGB16_Shader_Blitter::SkRGB16_Shader_Blitter(const SkPixmap& device,
                                                const SkPaint& paint,
                                                SkShader::Context* shaderContext)
     : INHERITED(device, paint, shaderContext)
 {
-    SkASSERT(paint.getXfermode() == nullptr);
+    SkASSERT(paint.isSrcOver());
 
     fBuffer = (SkPMColor*)sk_malloc_throw(device.width() * sizeof(SkPMColor));
 
     // compute SkBlitRow::Procs
     unsigned flags = 0;
 
     uint32_t shaderFlags = fShaderFlags;
     // shaders take care of global alpha, so we never set it in SkBlitRow
     if (!(shaderFlags & SkShader::kOpaqueAlpha_Flag)) {
         flags |= SkBlitRow::kSrcPixelAlpha_Flag;
@@ skipping 105 matching lines @@
     }
 }
 
 ///////////////////////////////////////////////////////////////////////
 
 SkRGB16_Shader_Xfermode_Blitter::SkRGB16_Shader_Xfermode_Blitter(
                                 const SkPixmap& device, const SkPaint& paint,
                                 SkShader::Context* shaderContext)
     : INHERITED(device, paint, shaderContext)
 {
-    fXfermode = paint.getXfermode();
+    fXfermode = SkXfermode::Peek(paint.getBlendMode());
     SkASSERT(fXfermode);
-    fXfermode->ref();
 
     int width = device.width();
     fBuffer = (SkPMColor*)sk_malloc_throw((width + (SkAlign4(width) >> 2)) * sizeof(SkPMColor));
     fAAExpand = (uint8_t*)(fBuffer + width);
 }
 
 SkRGB16_Shader_Xfermode_Blitter::~SkRGB16_Shader_Xfermode_Blitter() {
-    fXfermode->unref();
     sk_free(fBuffer);
 }
 
 void SkRGB16_Shader_Xfermode_Blitter::blitH(int x, int y, int width) {
     SkASSERT(x + width <= fDevice.width());
 
     uint16_t*   device = fDevice.writable_addr16(x, y);
     SkPMColor*  span = fBuffer;
 
     fShaderContext->shadeSpan(x, y, span, width);
@@ skipping 57 matching lines @@
 
 ///////////////////////////////////////////////////////////////////////////////
 
 SkBlitter* SkBlitter_ChooseD565(const SkPixmap& device, const SkPaint& paint,
         SkShader::Context* shaderContext,
         SkTBlitterAllocator* allocator) {
     SkASSERT(allocator != nullptr);
 
     SkBlitter* blitter;
     SkShader* shader = paint.getShader();
-    SkXfermode* mode = paint.getXfermode();
+    bool is_srcover = paint.isSrcOver();
 
     // we require a shader if there is an xfermode, handled by our caller
-    SkASSERT(nullptr == mode || shader);
+    SkASSERT(is_srcover || shader);
 
     if (shader) {
         SkASSERT(shaderContext != nullptr);
-        if (mode) {
+        if (!is_srcover) {
             blitter = allocator->createT<SkRGB16_Shader_Xfermode_Blitter>(device, paint,
                                                                           shaderContext);
         } else {
             blitter = allocator->createT<SkRGB16_Shader_Blitter>(device, paint, shaderContext);
         }
     } else {
         // no shader, no xfermode, (and we always ignore colorfilter)
         SkColor color = paint.getColor();
         if (0 == SkColorGetA(color)) {
             blitter = allocator->createT<SkNullBlitter>();
 #ifdef USE_BLACK_BLITTER
         } else if (SK_ColorBLACK == color) {
             blitter = allocator->createT<SkRGB16_Black_Blitter>(device, paint);
 #endif
         } else if (0xFF == SkColorGetA(color)) {
             blitter = allocator->createT<SkRGB16_Opaque_Blitter>(device, paint);
         } else {
             blitter = allocator->createT<SkRGB16_Blitter>(device, paint);
         }
     }
 
     return blitter;
 }