Simplify and reduce calls to beginTransparencyLayers.

sky/engine/core/rendering/RenderBox.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Adobe Systems Incorporated. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 692 matching lines @@
         return;
     }
 
     // The RenderView can't be transformed in Sky.
     ASSERT(layer()->parent());
 
     // If the transform can't be inverted, then don't paint anything.
     if (!layerTransform->isInvertible())
         return;
 
-    // If we have a transparency layer enclosing us and we are the root of a transform, then we need to establish the transparency
-    // layer from the parent now, assuming there is a parent
-    if (layer()->isTransparent()) {
-        layer()->parent()->beginTransparencyLayers(context, paintingInfo.rootLayer, paintingInfo.paintDirtyRect, paintingInfo.subPixelAccumulation);
-    }
-
     // Make sure the parent's clip rects have been calculated.
     ClipRectsContext clipRectsContext(paintingInfo.rootLayer, PaintingClipRects);
     ClipRect clipRect = layer()->clipper().backgroundClipRect(clipRectsContext);
     clipRect.intersect(paintingInfo.paintDirtyRect);
 
     // Push the parent coordinate space's clip.
     layer()->parent()->clipToRect(paintingInfo, context, clipRect);
 
     // This involves subtracting out the position of the layer in our current coordinate space, but preserving
     // the accumulated error for sub-pixel layout.
@@ skipping 18 matching lines @@
 
     // Restore the clip.
     layer()->parent()->restoreClip(context, paintingInfo.paintDirtyRect, clipRect);
 }
 
 void RenderBox::paintLayerContents(GraphicsContext* context, const LayerPaintingInfo& paintingInfo, const IntRect& rect)
 {
     float deviceScaleFactor = blink::deviceScaleFactor(frame());
     context->setDeviceScaleFactor(deviceScaleFactor);
 
-    GraphicsContext* transparencyLayerContext = context;
-
     LayoutPoint offsetFromRoot;
     layer()->convertToLayerCoords(paintingInfo.rootLayer, offsetFromRoot);
 
     LayerPaintingInfo localPaintingInfo(paintingInfo);
 
     LayoutRect layerBounds;
     // FIXME(sky): Remove foregroundRect. It's unused.
     ClipRect contentRect, foregroundRect;
     ClipRectsContext clipRectsContext(localPaintingInfo.rootLayer, PaintingClipRects, localPaintingInfo.subPixelAccumulation);
     layer()->clipper().calculateRects(clipRectsContext, localPaintingInfo.paintDirtyRect,
@@ skipping 22 matching lines @@
                 if (!rootRelativeBoundsComputed) {
                     rootRelativeBounds = layer()->physicalBoundingBoxIncludingReflectionAndStackingChildren(paintingInfo.rootLayer, offsetFromRoot);
                     rootRelativeBoundsComputed = true;
                 }
 
                 context->clipPath(clipPath->path(rootRelativeBounds), clipPath->windRule());
             }
         }
     }
 
-    bool haveTransparency = layer()->isTransparent();
+    if (layer()->isTransparent())
+        layer()->beginTransparencyLayers(context, localPaintingInfo.rootLayer, paintingInfo.paintDirtyRect, localPaintingInfo.subPixelAccumulation);
+
+    layer()->clipToRect(localPaintingInfo, context, contentRect);
 
     FilterEffectRendererHelper filterPainter(layer()->filterRenderer() && layer()->paintsWithFilters());
 
     if (filterPainter.haveFilterEffect()) {
         ASSERT(layer()->filterInfo());
 
         if (!rootRelativeBoundsComputed)
             rootRelativeBounds = layer()->physicalBoundingBoxIncludingReflectionAndStackingChildren(paintingInfo.rootLayer, offsetFromRoot);
 
-        if (filterPainter.prepareFilterEffect(layer(), rootRelativeBounds, paintingInfo.paintDirtyRect)) {
-            // Rewire the old context to a memory buffer, so that we can capture the contents of the layer.
-            // NOTE: We saved the old context in the "transparencyLayerContext" local variable, to be able to start a transparency layer
-            // on the original context and avoid duplicating "beginFilterEffect" after each transparency layer call. Also, note that
-            // beginTransparencyLayers will only create a single lazy transparency layer, even though it is called twice in this method.
-            // With deferred filters, we don't need a separate context, but we do need to do transparency and clipping before starting
-            // filter processing.
-            // FIXME: when the legacy path is removed, remove the transparencyLayerContext as well.
-            if (haveTransparency) {
-                // If we have a filter and transparency, we have to eagerly start a transparency layer here, rather than risk a child layer lazily starts one after filter processing.
-                layer()->beginTransparencyLayers(context, localPaintingInfo.rootLayer, paintingInfo.paintDirtyRect, paintingInfo.subPixelAccumulation);
-            }
-            // We'll handle clipping to the dirty rect before filter rasterization.
-            // Filter processing will automatically expand the clip rect and the offscreen to accommodate any filter outsets.
-            // FIXME: It is incorrect to just clip to the damageRect here once multiple fragments are involved.
-            layer()->clipToRect(localPaintingInfo, context, contentRect);
-            // Subsequent code should not clip to the dirty rect, since we've already
-            // done it above, and doing it later will defeat the outsets.
-            localPaintingInfo.clipToDirtyRect = false;
-
+        if (filterPainter.prepareFilterEffect(layer(), rootRelativeBounds, paintingInfo.paintDirtyRect))
             context = filterPainter.beginFilterEffect(context);
-        }
     }
 
     LayoutPoint layerLocation = toPoint(layerBounds.location() - location() + localPaintingInfo.subPixelAccumulation);
 
-    // Begin transparency if we have something to paint.
-    if (haveTransparency)
-        layer()->beginTransparencyLayers(transparencyLayerContext, localPaintingInfo.rootLayer, paintingInfo.paintDirtyRect, localPaintingInfo.subPixelAccumulation);
-
-    if (localPaintingInfo.clipToDirtyRect)
-        layer()->clipToRect(localPaintingInfo, context, contentRect);
-
     Vector<RenderBox*> layers;
     PaintInfo paintInfo(context, pixelSnappedIntRect(contentRect.rect()), localPaintingInfo.rootLayer->renderer());
     paint(paintInfo, layerLocation, layers);
 
     std::stable_sort(layers.begin(), layers.end(), forwardCompareZIndex);
     for (auto& box : layers) {
         box->paintLayer(context, paintingInfo.rootLayer, rect);
     }
 
-    if (localPaintingInfo.clipToDirtyRect)
-        layer()->restoreClip(context, localPaintingInfo.paintDirtyRect, contentRect);
+    if (filterPainter.hasStartedFilterEffect())
+        context = filterPainter.applyFilterEffect();
 
-    if (filterPainter.hasStartedFilterEffect()) {
-        context = filterPainter.applyFilterEffect();
-        layer()->restoreClip(transparencyLayerContext, localPaintingInfo.paintDirtyRect, contentRect);
-    }
+    layer()->restoreClip(context, localPaintingInfo.paintDirtyRect, contentRect);
 
-    // Make sure that we now use the original transparency context.
-    ASSERT(transparencyLayerContext == context);
-
-    // End our transparency layer
-    if (haveTransparency && layer()->usedTransparency()) {
+    if (layer()->isTransparent()) {
         context->endLayer();
         context->restore();
-        layer()->clearUsedTransparency();
     }
 }
 
 void RenderBox::paint(PaintInfo& paintInfo, const LayoutPoint& paintOffset, Vector<RenderBox*>& layers)
 {
     LayoutPoint adjustedPaintOffset = paintOffset + location();
     for (RenderObject* child = slowFirstChild(); child; child = child->nextSibling())
         child->paint(paintInfo, adjustedPaintOffset, layers);
 }
 
@@ skipping 2125 matching lines @@
 
 RenderBox::BoxDecorationData::BoxDecorationData(const RenderStyle& style)
 {
     backgroundColor = style.colorIncludingFallback(CSSPropertyBackgroundColor);
     hasBackground = backgroundColor.alpha() || style.hasBackgroundImage();
     ASSERT(hasBackground == style.hasBackground());
     hasBorder = style.hasBorder();
 }
 
 } // namespace blink