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

Source/core/html/canvas/CanvasRenderingContext2D.cpp

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2007 Alp Toker <alp@atoker.com>
  * Copyright (C) 2008 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2008 Dirk Schulze <krit@webkit.org>
  * Copyright (C) 2010 Torch Mobile (Beijing) Co. Ltd. All rights reserved.
  * Copyright (C) 2012, 2013 Intel Corporation. All rights reserved.
  * Copyright (C) 2013 Adobe Systems Incorporated. All rights reserved.
  *
@@ skipping 257 matching lines @@
     : m_unrealizedSaveCount(0)
     , m_strokeStyle(CanvasStyle::createFromRGBA(Color::black))
     , m_fillStyle(CanvasStyle::createFromRGBA(Color::black))
     , m_lineWidth(1)
     , m_lineCap(ButtCap)
     , m_lineJoin(MiterJoin)
     , m_miterLimit(10)
     , m_shadowBlur(0)
     , m_shadowColor(Color::transparent)
     , m_globalAlpha(1)
-    , m_globalComposite(CompositeSourceOver)
-    , m_globalBlend(WebBlendModeNormal)
+    , m_globalComposite(SkXfermode::kSrcOver_Mode)
     , m_invertibleCTM(true)
     , m_lineDashOffset(0)
     , m_imageSmoothingEnabled(true)
     , m_textAlign(StartTextAlign)
     , m_textBaseline(AlphabeticTextBaseline)
     , m_direction(DirectionInherit)
     , m_unparsedFont(defaultFont)
     , m_realizedFont(false)
     , m_hasClip(false)
 {
 }
 
 CanvasRenderingContext2D::State::State(const State& other, ClipListCopyMode mode)
     : CSSFontSelectorClient()
     , m_unrealizedSaveCount(other.m_unrealizedSaveCount)
     , m_unparsedStrokeColor(other.m_unparsedStrokeColor)
     , m_unparsedFillColor(other.m_unparsedFillColor)
     , m_strokeStyle(other.m_strokeStyle)
     , m_fillStyle(other.m_fillStyle)
     , m_lineWidth(other.m_lineWidth)
     , m_lineCap(other.m_lineCap)
     , m_lineJoin(other.m_lineJoin)
     , m_miterLimit(other.m_miterLimit)
     , m_shadowOffset(other.m_shadowOffset)
     , m_shadowBlur(other.m_shadowBlur)
     , m_shadowColor(other.m_shadowColor)
     , m_globalAlpha(other.m_globalAlpha)
     , m_globalComposite(other.m_globalComposite)
-    , m_globalBlend(other.m_globalBlend)
     , m_transform(other.m_transform)
     , m_invertibleCTM(other.m_invertibleCTM)
     , m_lineDashOffset(other.m_lineDashOffset)
     , m_imageSmoothingEnabled(other.m_imageSmoothingEnabled)
     , m_textAlign(other.m_textAlign)
     , m_textBaseline(other.m_textBaseline)
     , m_direction(other.m_direction)
     , m_unparsedFont(other.m_unparsedFont)
     , m_font(other.m_font)
     , m_realizedFont(other.m_realizedFont)
@@ skipping 23 matching lines @@
     m_fillStyle = other.m_fillStyle;
     m_lineWidth = other.m_lineWidth;
     m_lineCap = other.m_lineCap;
     m_lineJoin = other.m_lineJoin;
     m_miterLimit = other.m_miterLimit;
     m_shadowOffset = other.m_shadowOffset;
     m_shadowBlur = other.m_shadowBlur;
     m_shadowColor = other.m_shadowColor;
     m_globalAlpha = other.m_globalAlpha;
     m_globalComposite = other.m_globalComposite;
-    m_globalBlend = other.m_globalBlend;
     m_transform = other.m_transform;
     m_invertibleCTM = other.m_invertibleCTM;
     m_imageSmoothingEnabled = other.m_imageSmoothingEnabled;
     m_textAlign = other.m_textAlign;
     m_textBaseline = other.m_textBaseline;
     m_direction = other.m_direction;
     m_unparsedFont = other.m_unparsedFont;
     m_font = other.m_font;
     m_realizedFont = other.m_realizedFont;
     m_hasClip = other.m_hasClip;
@@ skipping 387 matching lines @@
     GraphicsContext* c = drawingContext();
     realizeSaves(c);
     modifiableState().m_globalAlpha = alpha;
     if (!c)
         return;
     c->setAlphaAsFloat(alpha);
 }
 
 String CanvasRenderingContext2D::globalCompositeOperation() const
 {
-    return compositeOperatorName(state().m_globalComposite, state().m_globalBlend);
+    return compositeOperatorName(compositeOperatorFromSkia(state().m_globalComposite), blendModeFromSkia(state().m_globalComposite));
 }
 
 void CanvasRenderingContext2D::setGlobalCompositeOperation(const String& operation)
 {
     CompositeOperator op = CompositeSourceOver;
     WebBlendMode blendMode = WebBlendModeNormal;
     if (!parseCompositeAndBlendOperator(operation, op, blendMode))
         return;
-    if ((state().m_globalComposite == op) && (state().m_globalBlend == blendMode))
+    SkXfermode::Mode xfermode = WebCoreCompositeToSkiaComposite(op, blendMode);
+    if (state().m_globalComposite == xfermode)
         return;
     GraphicsContext* c = drawingContext();
     realizeSaves(c);
-    modifiableState().m_globalComposite = op;
-    modifiableState().m_globalBlend = blendMode;
+    modifiableState().m_globalComposite = xfermode;
     if (!c)
         return;
-    c->setCompositeOperation(op, blendMode);
+    c->setCompositeOperation(xfermode);
 }
 
 void CanvasRenderingContext2D::setCurrentTransform(PassRefPtrWillBeRawPtr<SVGMatrixTearOff> passMatrixTearOff)
 {
     RefPtrWillBeRawPtr<SVGMatrixTearOff> matrixTearOff = passMatrixTearOff;
     const AffineTransform& transform = matrixTearOff->value();
     setTransform(transform.a(), transform.b(), transform.c(), transform.d(), transform.e(), transform.f());
 }
 
 void CanvasRenderingContext2D::scale(float sx, float sy)
@@ skipping 165 matching lines @@
     }
 
     if (height < 0) {
         height = -height;
         y -= height;
     }
 
     return true;
 }
 
-static bool isFullCanvasCompositeMode(CompositeOperator op)
+static bool isFullCanvasCompositeMode(SkXfermode::Mode op)
 {
     // See 4.8.11.1.3 Compositing
     // CompositeSourceAtop and CompositeDestinationOut are not listed here as the platforms already
     // implement the specification's behavior.
-    return op == CompositeSourceIn || op == CompositeSourceOut || op == CompositeDestinationIn || op == CompositeDestinationAtop;
+    return op == SkXfermode::kSrcIn_Mode || op == SkXfermode::kSrcOut_Mode || op == SkXfermode::kDstIn_Mode || op == SkXfermode::kDstATop_Mode;
 }
 
 static WindRule parseWinding(const String& windingRuleString)
 {
     if (windingRuleString == "nonzero")
         return RULE_NONZERO;
     if (windingRuleString == "evenodd")
         return RULE_EVENODD;
 
     ASSERT_NOT_REACHED();
@@ skipping 22 matching lines @@
     if (gradient && gradient->isZeroSize()) {
         return;
     }
 
     WindRule windRule = c->fillRule();
     c->setFillRule(parseWinding(windingRuleString));
 
     if (isFullCanvasCompositeMode(state().m_globalComposite)) {
         fullCanvasCompositedDraw(bind(&GraphicsContext::fillPath, c, path));
         didDraw(clipBounds);
-    } else if (state().m_globalComposite == CompositeCopy) {
+    } else if (state().m_globalComposite == SkXfermode::kSrc_Mode) {
         clearCanvas();
         c->clearShadow();
         c->fillPath(path);
         applyShadow(DrawShadowAndForeground);
         didDraw(clipBounds);
     } else {
         FloatRect dirtyRect;
         if (computeDirtyRect(path.boundingRect(), clipBounds, &dirtyRect)) {
             c->fillPath(path);
             didDraw(dirtyRect);
@@ skipping 31 matching lines @@
 
     // If gradient size is zero, then paint nothing.
     Gradient* gradient = c->strokeGradient();
     if (gradient && gradient->isZeroSize()) {
         return;
     }
 
     if (isFullCanvasCompositeMode(state().m_globalComposite)) {
         fullCanvasCompositedDraw(bind(&GraphicsContext::strokePath, c, path));
         didDraw(clipBounds);
-    } else if (state().m_globalComposite == CompositeCopy) {
+    } else if (state().m_globalComposite == SkXfermode::kSrc_Mode) {
         clearCanvas();
         c->clearShadow();
         c->strokePath(path);
         applyShadow(DrawShadowAndForeground);
         didDraw(clipBounds);
     } else {
         FloatRect bounds = path.boundingRect();
         inflateStrokeRect(bounds);
         FloatRect dirtyRect;
         if (computeDirtyRect(bounds, clipBounds, &dirtyRect)) {
@@ skipping 161 matching lines @@
         saved = true;
         context->clearShadow();
     }
     if (state().m_globalAlpha != 1) {
         if (!saved) {
             context->save();
             saved = true;
         }
         context->setAlphaAsFloat(1);
     }
-    if (state().m_globalComposite != CompositeSourceOver) {
+    if (state().m_globalComposite != SkXfermode::kSrcOver_Mode) {
         if (!saved) {
             context->save();
             saved = true;
         }
-        context->setCompositeOperation(CompositeSourceOver);
+        context->setCompositeOperation(SkXfermode::kSrcOver_Mode);
     }
     context->clearRect(rect);
     if (m_hitRegionManager)
         m_hitRegionManager->removeHitRegionsInRect(rect, state().m_transform);
     if (saved)
         context->restore();
 
     validateStateStack();
     didDraw(dirtyRect);
 }
@@ skipping 30 matching lines @@
     if (gradient && gradient->isZeroSize())
         return;
 
     FloatRect rect(x, y, width, height);
     if (rectContainsTransformedRect(rect, clipBounds)) {
         c->fillRect(rect);
         didDraw(clipBounds);
     } else if (isFullCanvasCompositeMode(state().m_globalComposite)) {
         fullCanvasCompositedDraw(bind(&fillRectOnContext, c, rect));
         didDraw(clipBounds);
-    } else if (state().m_globalComposite == CompositeCopy) {
+    } else if (state().m_globalComposite == SkXfermode::kSrc_Mode) {
         clearCanvas();
         c->clearShadow();
         c->fillRect(rect);
         applyShadow(DrawShadowAndForeground);
         didDraw(clipBounds);
     } else {
         FloatRect dirtyRect;
         if (computeDirtyRect(rect, clipBounds, &dirtyRect)) {
             c->fillRect(rect);
             didDraw(dirtyRect);
@@ skipping 20 matching lines @@
 
     // If gradient size is zero, then paint nothing.
     Gradient* gradient = c->strokeGradient();
     if (gradient && gradient->isZeroSize())
         return;
 
     FloatRect rect(x, y, width, height);
     if (isFullCanvasCompositeMode(state().m_globalComposite)) {
         fullCanvasCompositedDraw(bind(&strokeRectOnContext, c, rect));
         didDraw(clipBounds);
-    } else if (state().m_globalComposite == CompositeCopy) {
+    } else if (state().m_globalComposite == SkXfermode::kSrc_Mode) {
         clearCanvas();
         c->clearShadow();
         c->strokeRect(rect);
         applyShadow(DrawShadowAndForeground);
         didDraw(clipBounds);
     } else {
         FloatRect boundingRect = rect;
         boundingRect.inflate(state().m_lineWidth / 2);
         FloatRect dirtyRect;
         if (computeDirtyRect(boundingRect, clipBounds, &dirtyRect)) {
@@ skipping 153 matching lines @@
         canvas()->buffer()->willDrawVideo();
 
     // FIXME: crbug.com/447218
     // We make the destination canvas fall out of display list mode by calling
     // willAccessPixels. This is to prevent run-away memory consumption caused by SkSurface
     // copyOnWrite when the source canvas is animated and consumed at a rate higher than the
     // presentation frame rate of the destination canvas.
     if (imageSource->isCanvasElement())
         canvas()->buffer()->willAccessPixels();
 
-    CompositeOperator op = state().m_globalComposite;
     if (rectContainsTransformedRect(dstRect, clipBounds)) {
         drawImageOnContext(c, imageSource, image.get(), srcRect, dstRect);
         didDraw(clipBounds);
-    } else if (isFullCanvasCompositeMode(op)) {
+    } else if (isFullCanvasCompositeMode(state().m_globalComposite)) {
         fullCanvasCompositedDraw(bind(&drawImageOnContext, c, imageSource, image.get(), srcRect, dstRect));
         didDraw(clipBounds);
-    } else if (op == CompositeCopy) {
+    } else if (state().m_globalComposite == SkXfermode::kSrc_Mode) {
         clearCanvas();
         drawImageOnContext(c, imageSource, image.get(), srcRect, dstRect);
         didDraw(clipBounds);
     } else {
         FloatRect dirtyRect;
         if (computeDirtyRect(dstRect, clipBounds, &dirtyRect)) {
             drawImageOnContext(c, imageSource, image.get(), srcRect, dstRect);
             didDraw(dirtyRect);
         }
     }
@@ skipping 26 matching lines @@
     return state().m_transform.mapQuad(quad).containsQuad(transformedQuad);
 }
 
 void CanvasRenderingContext2D::fullCanvasCompositedDraw(PassOwnPtr<Closure> draw)
 {
     ASSERT(isFullCanvasCompositeMode(state().m_globalComposite));
 
     GraphicsContext* c = drawingContext();
     ASSERT(c);
 
-    CompositeOperator previousOperator = c->compositeOperation();
     if (shouldDrawShadows()) {
         // unroll into two independently composited passes if drawing shadows
         c->beginLayer(1, state().m_globalComposite);
-        c->setCompositeOperation(CompositeSourceOver);
+        c->setCompositeOperation(SkXfermode::kSrcOver_Mode);
         applyShadow(DrawShadowOnly);
         (*draw)();
-        c->setCompositeOperation(previousOperator);
+        c->setCompositeOperation(state().m_globalComposite);
         c->endLayer();
     }
 
     c->beginLayer(1, state().m_globalComposite);
     c->clearShadow();
-    c->setCompositeOperation(CompositeSourceOver);
+    c->setCompositeOperation(SkXfermode::kSrcOver_Mode);
     (*draw)();
-    c->setCompositeOperation(previousOperator);
+    c->setCompositeOperation(state().m_globalComposite);
     c->endLayer();
     applyShadow(DrawShadowAndForeground); // go back to normal shadows mode
 }
 
 PassRefPtrWillBeRawPtr<CanvasGradient> CanvasRenderingContext2D::createLinearGradient(float x0, float y0, float x1, float y1)
 {
     RefPtrWillBeRawPtr<CanvasGradient> gradient = CanvasGradient::create(FloatPoint(x0, y0), FloatPoint(x1, y1));
     return gradient.release();
 }
 
@@ skipping 543 matching lines @@
     }
 
     FloatRect clipBounds;
     if (!c->getTransformedClipBounds(&clipBounds)) {
         return;
     }
 
     if (isFullCanvasCompositeMode(state().m_globalComposite)) {
         fullCanvasCompositedDraw(bind(&GraphicsContext::drawBidiText, c, font, textRunPaintInfo, location, Font::UseFallbackIfFontNotReady));
         didDraw(clipBounds);
-    } else if (state().m_globalComposite == CompositeCopy) {
+    } else if (state().m_globalComposite == SkXfermode::kSrc_Mode) {
         clearCanvas();
         c->clearShadow();
         c->drawBidiText(font, textRunPaintInfo, location, Font::UseFallbackIfFontNotReady);
         applyShadow(DrawShadowAndForeground);
         didDraw(clipBounds);
     } else {
         FloatRect dirtyRect;
         if (computeDirtyRect(textRunPaintInfo.bounds, clipBounds, &dirtyRect)) {
             c->drawBidiText(font, textRunPaintInfo, location, Font::UseFallbackIfFontNotReady);
             didDraw(dirtyRect);
@@ skipping 131 matching lines @@
     StrokeData strokeData;
     strokeData.setThickness(focusRingWidth);
 
     FloatRect dirtyRect;
     if (!computeDirtyRect(path.strokeBoundingRect(strokeData), &dirtyRect))
         return;
 
     c->save();
     c->setAlphaAsFloat(1.0);
     c->clearShadow();
-    c->setCompositeOperation(CompositeSourceOver, WebBlendModeNormal);
+    c->setCompositeOperation(SkXfermode::kSrcOver_Mode);
     c->drawFocusRing(path, focusRingWidth, focusRingOutline, focusRingColor);
     c->restore();
     validateStateStack();
     didDraw(dirtyRect);
 }
 
 void CanvasRenderingContext2D::addHitRegion(const HitRegionOptions& options, ExceptionState& exceptionState)
 {
     if (options.id().isEmpty() && !options.control()) {
         exceptionState.throwDOMException(NotSupportedError, "Both id and control are null.");
@@ skipping 55 matching lines @@
 
 unsigned CanvasRenderingContext2D::hitRegionsCount() const
 {
     if (m_hitRegionManager)
         return m_hitRegionManager->getHitRegionsCount();
 
     return 0;
 }
 
 } // namespace blink