cc: Split out calcDrawEtc from drawLayers

cc/layer_tree_host_impl.cc

Index: cc/layer_tree_host_impl.cc
diff --git a/cc/layer_tree_host_impl.cc b/cc/layer_tree_host_impl.cc
index c295e920432a6a22acd80869e3e09b513de998f1..857647838d2e3f6053bd42f629333f49e525a3d2 100644
--- a/cc/layer_tree_host_impl.cc
+++ b/cc/layer_tree_host_impl.cc
@@ -216,6 +216,7 @@ LayerTreeHostImpl::LayerTreeHostImpl(const LayerTreeSettings& settings, LayerTre
                             PriorityCalculator::allowNothingCutoff())
     , m_backgroundColor(0)
     , m_hasTransparentBackground(false)
+    , m_needsUpdateDrawProperties(false)
     , m_pinchGestureActive(false)
     , m_fpsCounter(FrameRateCounter::create(m_proxy->hasImplThread()))
     , m_debugRectHistory(DebugRectHistory::create())
@@ -252,6 +253,14 @@ void LayerTreeHostImpl::beginCommit()
 void LayerTreeHostImpl::commitComplete()
 {
     TRACE_EVENT0("cc", "LayerTreeHostImpl::commitComplete");
+
+    // Impl-side painting needs an update immediately post-commit to have the
+    // opportunity to create tilings.  Other paths can call updateDrawProperties
+    // more lazily when needed prior to drawing.
+    setNeedsUpdateDrawProperties();
+    if (m_settings.implSidePainting)
+        updateDrawProperties();
+
     // Recompute max scroll position; must be after layer content bounds are
     // updated.
     updateMaxScrollOffset();
@@ -329,6 +338,7 @@ void LayerTreeHostImpl::startPageScaleAnimation(gfx::Vector2d targetOffset, bool
         m_pageScaleAnimation->zoomTo(scaledTargetOffset, pageScale, duration.InSecondsF());
     }
 
+    setNeedsUpdateDrawProperties();
     m_client->setNeedsRedrawOnImplThread();
     m_client->setNeedsCommitOnImplThread();
 }
@@ -374,20 +384,31 @@ void LayerTreeHostImpl::updateRootScrollLayerImplTransform()
     }
 }
 
+void LayerTreeHostImpl::updateDrawProperties()
+{
+    if (!needsUpdateDrawProperties())
+        return;
+
+    m_renderSurfaceLayerList.clear();
+    m_needsUpdateDrawProperties = false;
+
+    if (!rootLayer())
+        return;
+
+    calculateRenderSurfaceLayerList(m_renderSurfaceLayerList);
+}
+
 void LayerTreeHostImpl::calculateRenderSurfaceLayerList(LayerList& renderSurfaceLayerList)
 {
     DCHECK(renderSurfaceLayerList.empty());
     DCHECK(rootLayer());
     DCHECK(m_renderer); // For maxTextureSize.
-
     {
         updateRootScrollLayerImplTransform();
 
         TRACE_EVENT0("cc", "LayerTreeHostImpl::calcDrawEtc");
         float pageScaleFactor = m_pinchZoomViewport.pageScaleFactor();
         LayerTreeHostCommon::calculateDrawProperties(rootLayer(), deviceViewportSize(), m_deviceScaleFactor, pageScaleFactor, rendererCapabilities().maxTextureSize, renderSurfaceLayerList);
-
-        trackDamageForAllSurfaces(rootLayer(), renderSurfaceLayerList);
     }
 }
 
@@ -487,7 +508,8 @@ bool LayerTreeHostImpl::calculateRenderPasses(FrameData& frame)
 {
     DCHECK(frame.renderPasses.empty());
 
-    calculateRenderSurfaceLayerList(*frame.renderSurfaceLayerList);
+    updateDrawProperties();
+    trackDamageForAllSurfaces(rootLayer(), *frame.renderSurfaceLayerList);
 
     TRACE_EVENT1("cc", "LayerTreeHostImpl::calculateRenderPasses", "renderSurfaceLayerList.size()", static_cast<long long unsigned>(frame.renderSurfaceLayerList->size()));
 
@@ -533,6 +555,7 @@ bool LayerTreeHostImpl::calculateRenderPasses(FrameData& frame)
             if (occlusionTracker.occluded(it->renderTarget(), it->visibleContentRect(), it->drawTransform(), implDrawTransformIsUnknown, it->drawableContentRect(), &hasOcclusionFromOutsideTargetSurface))
                 appendQuadsData.hadOcclusionFromOutsideTargetSurface |= hasOcclusionFromOutsideTargetSurface;
             else {
+                DCHECK_EQ(this, it->layerTreeHostImpl());
                 it->willDraw(m_resourceProvider.get());
                 frame.willDrawLayers.push_back(*it);
 
@@ -718,7 +741,6 @@ bool LayerTreeHostImpl::prepareToDraw(FrameData& frame)
     frame.renderSurfaceLayerList = &m_renderSurfaceLayerList;
     frame.renderPasses.clear();
     frame.renderPassesById.clear();
-    frame.renderSurfaceLayerList->clear();
     frame.willDrawLayers.clear();
 
     if (!calculateRenderPasses(frame))
@@ -914,13 +936,15 @@ static LayerImpl* findScrollLayerForContentLayer(LayerImpl* layerImpl)
 void LayerTreeHostImpl::setRootLayer(scoped_ptr<LayerImpl> layer)
 {
   m_activeTree->SetRootLayer(layer.Pass());
+  setNeedsUpdateDrawProperties();

[danakj, 2012/12/07 21:14:02]

nit: 4 space indents

[enne (OOO), 2012/12/07 23:03:00]

Done.

 }
 
 scoped_ptr<LayerImpl> LayerTreeHostImpl::detachLayerTree()
 {
-  scoped_ptr<LayerImpl> layer = m_activeTree->DetachLayerTree();
-  m_renderSurfaceLayerList.clear();
-  return layer.Pass();
+    scoped_ptr<LayerImpl> layer = m_activeTree->DetachLayerTree();
+    m_renderSurfaceLayerList.clear();
+    setNeedsUpdateDrawProperties();
+    return layer.Pass();
 }
 
 void LayerTreeHostImpl::setVisible(bool visible)
@@ -1053,10 +1077,8 @@ void LayerTreeHostImpl::setPageScaleFactorAndLimits(float pageScaleFactor, float
     float pageScaleChange = pageScaleFactor / m_pinchZoomViewport.pageScaleFactor();
     m_pinchZoomViewport.setPageScaleFactorAndLimits(pageScaleFactor, minPageScaleFactor, maxPageScaleFactor);
 
-    if (!m_settings.pageScalePinchZoomEnabled) {
-        if (pageScaleChange != 1)
-            adjustScrollsForPageScaleChange(rootScrollLayer(), pageScaleChange);
-    }
+    if (!m_settings.pageScalePinchZoomEnabled && pageScaleChange != 1)
+        adjustScrollsForPageScaleChange(rootScrollLayer(), pageScaleChange);
 
     // Clamp delta to limits and refresh display matrix.
     setPageScaleDelta(m_pinchZoomViewport.pageScaleDelta() / m_pinchZoomViewport.sentPageScaleDelta());
@@ -1124,8 +1146,8 @@ bool LayerTreeHostImpl::ensureRenderSurfaceLayerList()
     // If we are called after setRootLayer() but before prepareToDraw(), we need
     // to recalculate the visible layers. This prevents being unable to scroll
     // during part of a commit.
-    m_renderSurfaceLayerList.clear();
-    calculateRenderSurfaceLayerList(m_renderSurfaceLayerList);
+    setNeedsUpdateDrawProperties();

[danakj, 2012/12/07 21:14:02]

Ok, throw a big TODO here please and file a bug. The above check can be a false
positive now.

[enne (OOO), 2012/12/07 23:03:00]

Done.  https://code.google.com/p/chromium/issues/detail?id=164949

+    updateDrawProperties();
 
     return m_renderSurfaceLayerList.size();
 }
@@ -1178,6 +1200,7 @@ InputHandlerClient::ScrollStatus LayerTreeHostImpl::scrollBegin(gfx::Point viewp
         // events are already in local layer coordinates so we can just apply them directly.
         m_scrollDeltaIsInViewportSpace = (type == Gesture);
         m_numImplThreadScrolls++;
+        setNeedsUpdateDrawProperties();
         return ScrollStarted;
     }
     return ScrollIgnored;
@@ -1292,6 +1315,7 @@ bool LayerTreeHostImpl::scrollBy(const gfx::Point& viewportPoint,
     if (didScroll) {
         m_client->setNeedsCommitOnImplThread();
         m_client->setNeedsRedrawOnImplThread();
+        setNeedsUpdateDrawProperties();
     }
     return didScroll;
 }
@@ -1346,6 +1370,7 @@ void LayerTreeHostImpl::pinchGestureUpdate(float magnifyDelta, gfx::Point anchor
 
     m_client->setNeedsCommitOnImplThread();
     m_client->setNeedsRedrawOnImplThread();
+    setNeedsUpdateDrawProperties();
 }
 
 void LayerTreeHostImpl::pinchGestureEnd()
@@ -1482,6 +1507,7 @@ void LayerTreeHostImpl::animatePageScale(base::TimeTicks time)
         nextScroll.Scale(m_pinchZoomViewport.pageScaleFactor());
     rootScrollLayer()->scrollBy(nextScroll - scrollTotal);
     m_client->setNeedsRedrawOnImplThread();
+    setNeedsUpdateDrawProperties();
 
     if (m_pageScaleAnimation->isAnimationCompleteAtTime(monotonicTime)) {
         m_pageScaleAnimation.reset();
@@ -1503,10 +1529,12 @@ void LayerTreeHostImpl::animateLayers(base::TimeTicks monotonicTime, base::Time
     for (AnimationControllerSet::iterator iter = copy.begin(); iter != copy.end(); ++iter)
         (*iter)->animate(monotonicSeconds, events.get());
 
+    if (copy.size() > 0)

[danakj, 2012/12/07 21:14:02]

nit: !copy.empty()

Or even better, save !m_activeAnimationControllers.empty() in nicely named temp
bool before the iteration.

[enne (OOO), 2012/12/07 23:03:00]

Actually, there's an early out for no active controllers earlier in the
function, so removed.

+      m_client->setNeedsRedrawOnImplThread();

[danakj, 2012/12/07 21:14:02]

did you mean to setNeedsUpdateDrawProperties() here too?

[enne (OOO), 2012/12/07 23:03:00]

Done.

+
     if (!events->empty())
         m_client->postAnimationEventsToMainThreadOnImplThread(events.Pass(), wallClockTime);
 
-    m_client->setNeedsRedrawOnImplThread();
     setBackgroundTickingEnabled(!m_visible && !m_activeAnimationControllers.empty());
 }
 
@@ -1539,6 +1567,7 @@ void LayerTreeHostImpl::clearRenderSurfaces()
 {
     clearRenderSurfacesOnLayerImplRecursive(rootLayer());
     m_renderSurfaceLayerList.clear();
+    setNeedsUpdateDrawProperties();
 }
 
 std::string LayerTreeHostImpl::layerTreeAsText() const