Changeset 98757 in webkit

Timestamp:

Oct 28, 2011, 1:44:58 PM (15 years ago)

Author:

enne@google.com

Message:

[chromium] Implicitly skip render surfaces that won't be drawn
​https://bugs.webkit.org/show_bug.cgi?id=71038

Rather than having redundant checks in three places for how to walk
through a render surface list, instead don't add render surfaces that
don't need to get rendered to the render surface list.

Reviewed by James Robinson.

Covered by existing layout tests.

• platform/graphics/chromium/LayerRendererChromium.cpp:

(WebCore::LayerRendererChromium::drawLayersOntoRenderSurfaces):

• platform/graphics/chromium/cc/CCLayerTreeHost.cpp:

(WebCore::CCLayerTreeHost::paintLayerContents):
(WebCore::CCLayerTreeHost::updateCompositorResources):

• platform/graphics/chromium/cc/CCLayerTreeHostCommon.cpp:

(WebCore::calculateDrawTransformsAndVisibilityInternal):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• platform/graphics/chromium/LayerRendererChromium.cpp (modified) (1 diff)
• platform/graphics/chromium/cc/CCLayerTreeHost.cpp (modified) (2 diffs)
• platform/graphics/chromium/cc/CCLayerTreeHostCommon.cpp (modified) (4 diffs)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2011-10-28  Adrienne Walker  <enne@google.com>
+
+        [chromium] Implicitly skip render surfaces that won't be drawn
+        https://bugs.webkit.org/show_bug.cgi?id=71038
+
+        Rather than having redundant checks in three places for how to walk
+        through a render surface list, instead don't add render surfaces that
+        don't need to get rendered to the render surface list.
+
+        Reviewed by James Robinson.
+
+        Covered by existing layout tests.
+
+        * platform/graphics/chromium/LayerRendererChromium.cpp:
+        (WebCore::LayerRendererChromium::drawLayersOntoRenderSurfaces):
+        * platform/graphics/chromium/cc/CCLayerTreeHost.cpp:
+        (WebCore::CCLayerTreeHost::paintLayerContents):
+        (WebCore::CCLayerTreeHost::updateCompositorResources):
+        * platform/graphics/chromium/cc/CCLayerTreeHostCommon.cpp:
+        (WebCore::calculateDrawTransformsAndVisibilityInternal):
+
 2011-10-28  Adam Barth  <abarth@webkit.org>
 

trunk/Source/WebCore/platform/graphics/chromium/LayerRendererChromium.cpp

@@ -313 +313 @@
         CCRenderSurface* renderSurface = renderSurfaceLayer->renderSurface();
         ASSERT(renderSurface);
-
-        renderSurface->setSkipsDraw(true);
-
-        if (!renderSurface->layerList().size())
-            continue;
-
-        // Skip completely transparent render surfaces.
-        if (!renderSurface->drawOpacity())
-            continue;
+        ASSERT(renderSurface->layerList().size());
+        ASSERT(renderSurface->drawOpacity());
 
         if (useRenderSurface(renderSurface)) {
-            renderSurface->setSkipsDraw(false);
-
             if (renderSurfaceLayer != rootDrawLayer) {
                 GLC(m_context.get(), m_context->disable(GraphicsContext3D::SCISSOR_TEST));

trunk/Source/WebCore/platform/graphics/chromium/cc/CCLayerTreeHost.cpp

@@ -331 +331 @@
         RenderSurfaceChromium* renderSurface = renderSurfaceLayer->renderSurface();
         ASSERT(renderSurface);
-
-        // Render surfaces whose drawable area has zero width or height
-        // will have no layers associated with them and should be skipped.
-        if (!renderSurface->layerList().size())
-            continue;
-
-        if (!renderSurface->drawOpacity())
-            continue;
+        ASSERT(renderSurface->layerList().size());
+        ASSERT(renderSurface->drawOpacity());
 
         renderSurfaceLayer->setLayerTreeHost(this);
@@ -371 +365 @@
         RenderSurfaceChromium* renderSurface = renderSurfaceLayer->renderSurface();
         ASSERT(renderSurface);
-
-        if (!renderSurface->layerList().size() || !renderSurface->drawOpacity())
-            continue;
+        ASSERT(renderSurface->layerList().size());
+        ASSERT(renderSurface->drawOpacity());
 
         if (renderSurfaceLayer->maskLayer())

trunk/Source/WebCore/platform/graphics/chromium/cc/CCLayerTreeHostCommon.cpp

@@ -233 +233 @@
     bool useSurfaceForFlatDescendants = layer->parent() && layer->parent()->preserves3D() && !layer->preserves3D() && layer->descendantDrawsContent();
     if (useSurfaceForMasking || useSurfaceForReflection || useSurfaceForFlatDescendants || ((useSurfaceForClipping || useSurfaceForOpacity) && layer->descendantDrawsContent())) {
+        // Layer's opacity will be applied when drawing the render surface.
+        float drawOpacity = layer->opacity();
+        if (layer->parent() && layer->parent()->preserves3D())
+            drawOpacity *= layer->parent()->drawOpacity();
+
+        // If this render surface isn't drawn, we can also skip its children.
+        if (!drawOpacity)
+            return;
+
         if (!layer->renderSurface())
             layer->createRenderSurface();
+
         RenderSurfaceType* renderSurface = layer->renderSurface();
+        renderSurface->clearLayerList();
 
         // The origin of the new surface is the upper left corner of the layer.
@@ -244 +255 @@
         transformedLayerRect = IntRect(0, 0, bounds.width(), bounds.height());
 
-        // Layer's opacity will be applied when drawing the render surface.
-        float drawOpacity = layer->opacity();
-        if (layer->parent() && layer->parent()->preserves3D())
-            drawOpacity *= layer->parent()->drawOpacity();
         renderSurface->setDrawOpacity(drawOpacity);
         layer->setDrawOpacity(1);
@@ -262 +269 @@
         // surface and is therefore expressed in the parent's coordinate system.
         renderSurface->setScissorRect(layer->parent() ? layer->parent()->scissorRect() : layer->scissorRect());
-
-        renderSurface->clearLayerList();
 
         if (layer->maskLayer()) {
@@ -372 +377 @@
     }
 
+    if (layer->renderSurface() && !layer->renderSurface()->layerList().size()) {
+        // If a render surface has no layer list, then it and none of its
+        // children needed to get drawn. Therefore, it should be the last layer
+        // in the render surface list and we can trivially remove it.
+        ASSERT(renderSurfaceLayerList.last() == layer);
+        renderSurfaceLayerList.removeLast();
+        layer->clearRenderSurface();
+        return;
+    }
+
+    // If neither this layer nor any of its children were added, early out.
+    if (sortingStartIndex == descendants.size())
+        return;
+
     if (layer->masksToBounds() || useSurfaceForMasking) {
         IntRect drawableContentRect = layer->drawableContentRect();