Make beginLayer() and CanvasRenderingContext2D use SkXfermode::Mode.

Source/platform/graphics/skia/SkiaUtils.cpp

 /*
  * Copyright (c) 2006,2007,2008, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 61 matching lines @@
     SkXfermode::kDifference_Mode, // WebBlendModeDifference
     SkXfermode::kExclusion_Mode, // WebBlendModeExclusion
     SkXfermode::kHue_Mode, // WebBlendModeHue
     SkXfermode::kSaturation_Mode, // WebBlendModeSaturation
     SkXfermode::kColor_Mode, // WebBlendModeColor
     SkXfermode::kLuminosity_Mode // WebBlendModeLuminosity
 };
 
 SkXfermode::Mode WebCoreCompositeToSkiaComposite(CompositeOperator op, WebBlendMode blendMode)
 {
+    ASSERT(op == CompositeSourceOver || blendMode == WebBlendModeNormal);
     if (blendMode != WebBlendModeNormal) {
         if (static_cast<uint8_t>(blendMode) >= SK_ARRAY_COUNT(gMapBlendOpsToXfermodeModes)) {
             SkDEBUGF(("GraphicsContext::setPlatformCompositeOperation unknown WebBlendMode %d\n", blendMode));
             return SkXfermode::kSrcOver_Mode;
         }
         return gMapBlendOpsToXfermodeModes[static_cast<uint8_t>(blendMode)];
     }
 
     const CompositOpToXfermodeMode* table = gMapCompositOpsToXfermodeModes;
     if (static_cast<uint8_t>(op) >= SK_ARRAY_COUNT(gMapCompositOpsToXfermodeModes)) {
         SkDEBUGF(("GraphicsContext::setPlatformCompositeOperation unknown CompositeOperator %d\n", op));
         return SkXfermode::kSrcOver_Mode;
     }
     SkASSERT(table[static_cast<uint8_t>(op)].mCompositOp == op);
     return table[static_cast<uint8_t>(op)].m_xfermodeMode;
 }
 
+CompositeOperator compositeOperatorFromSkia(SkXfermode::Mode xferMode)
+{
+    switch (xferMode) {
+    case SkXfermode::kClear_Mode:
+        return CompositeClear;
+    case SkXfermode::kSrc_Mode:
+        return CompositeCopy;
+    case SkXfermode::kSrcOver_Mode:
+        return CompositeSourceOver;
+    case SkXfermode::kSrcIn_Mode:
+        return CompositeSourceIn;
+    case SkXfermode::kSrcOut_Mode:
+        return CompositeSourceOut;
+    case SkXfermode::kSrcATop_Mode:
+        return CompositeSourceAtop;
+    case SkXfermode::kDstOver_Mode:
+        return CompositeDestinationOver;
+    case SkXfermode::kDstIn_Mode:
+        return CompositeDestinationIn;
+    case SkXfermode::kDstOut_Mode:
+        return CompositeDestinationOut;
+    case SkXfermode::kDstATop_Mode:
+        return CompositeDestinationAtop;
+    case SkXfermode::kXor_Mode:
+        return CompositeXOR;
+    case SkXfermode::kPlus_Mode:
+        return CompositePlusLighter;
+    default:
+        break;
+    }
+    return CompositeSourceOver;
+}
+
+WebBlendMode blendModeFromSkia(SkXfermode::Mode xferMode)
+{
+    switch (xferMode) {
+    case SkXfermode::kSrcOver_Mode:
+        return WebBlendModeNormal;
+    case SkXfermode::kMultiply_Mode:
+        return WebBlendModeMultiply;
+    case SkXfermode::kScreen_Mode:
+        return WebBlendModeScreen;
+    case SkXfermode::kOverlay_Mode:
+        return WebBlendModeOverlay;
+    case SkXfermode::kDarken_Mode:
+        return WebBlendModeDarken;
+    case SkXfermode::kLighten_Mode:
+        return WebBlendModeLighten;
+    case SkXfermode::kColorDodge_Mode:
+        return WebBlendModeColorDodge;
+    case SkXfermode::kColorBurn_Mode:
+        return WebBlendModeColorBurn;
+    case SkXfermode::kHardLight_Mode:
+        return WebBlendModeHardLight;
+    case SkXfermode::kSoftLight_Mode:
+        return WebBlendModeSoftLight;
+    case SkXfermode::kDifference_Mode:
+        return WebBlendModeDifference;
+    case SkXfermode::kExclusion_Mode:
+        return WebBlendModeExclusion;
+    case SkXfermode::kHue_Mode:
+        return WebBlendModeHue;
+    case SkXfermode::kSaturation_Mode:
+        return WebBlendModeSaturation;
+    case SkXfermode::kColor_Mode:
+        return WebBlendModeColor;
+    case SkXfermode::kLuminosity_Mode:
+        return WebBlendModeLuminosity;
+    default:
+        break;
+    }
+    return WebBlendModeNormal;
+}
+
 bool SkPathContainsPoint(const SkPath& originalPath, const FloatPoint& point, SkPath::FillType ft)
 {
     SkRect bounds = originalPath.getBounds();
 
     // We can immediately return false if the point is outside the bounding
     // rect.  We don't use bounds.contains() here, since it would exclude
     // points on the right and bottom edges of the bounding rect, and we want
     // to include them.
     SkScalar fX = SkFloatToScalar(point.x());
     SkScalar fY = SkFloatToScalar(point.y());
@@ skipping 170 matching lines @@
     // though - that's why it's not always on.
     SkScalar widthExpansion, heightExpansion;
     if (totalMatrix.getType() & SkMatrix::kAffine_Mask)
         widthExpansion = totalMatrix[SkMatrix::kMSkewY], heightExpansion = totalMatrix[SkMatrix::kMSkewX];
     else
         widthExpansion = totalMatrix[SkMatrix::kMScaleX], heightExpansion = totalMatrix[SkMatrix::kMScaleY];
     return destRect.width() * fabs(widthExpansion) < 1 || destRect.height() * fabs(heightExpansion) < 1;
 }
 
 }  // namespace blink