Blink changes to record interest rects for http://w3c.github.io/frame-timing/

Source/core/frame/FrameView.cpp

 /*
  * Copyright (C) 1998, 1999 Torben Weis <weis@kde.org>
  *                     1999 Lars Knoll <knoll@kde.org>
  *                     1999 Antti Koivisto <koivisto@kde.org>
  *                     2000 Dirk Mueller <mueller@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  *           (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
@@ skipping 2517 matching lines @@
     if (view) {
         TRACE_EVENT_INSTANT1(TRACE_DISABLED_BY_DEFAULT("devtools.timeline"), "UpdateLayerTree", TRACE_EVENT_SCOPE_THREAD, "data", InspectorUpdateLayerTreeEvent::data(m_frame.get()));
 
         view->compositor()->updateIfNeededRecursive();
 
         if (view->compositor()->inCompositingMode() && m_frame->isLocalRoot())
             scrollingCoordinator()->updateAfterCompositingChangeIfNeeded();
 
         updateCompositedSelectionIfNeeded();
 
+        if (RuntimeEnabledFeatures::frameTimingSupportEnabled())
+            updateFrameTimingRequestsIfNeeded();
+
         scrollContentsIfNeededRecursive();
 
         invalidateTreeIfNeededRecursive();
 
         ASSERT(!view->hasPendingSelection());
     }
 
     ASSERT(lifecycle().state() == DocumentLifecycle::PaintInvalidationClean);
 }
 
+void FrameView::updateFrameTimingRequestsIfNeeded()
+{
+    GraphicsLayerFrameTimingRequests graphicsLayerTimingRequests;

[chrishtr, 2015/05/08 16:52:04]

Add a TODO(mpb) to add the dirty bit.

[MikeB, 2015/05/08 18:37:34]

Done.

+    collectFrameTimingRequestsRecursive(graphicsLayerTimingRequests);
+
+    for (const auto& iter : graphicsLayerTimingRequests) {
+        const GraphicsLayer* graphicsLayer = iter.key;
+        graphicsLayer->platformLayer()->setFrameTimingRequests(iter.value);
+    }
+}
+
 void FrameView::updateLayoutAndStyleIfNeededRecursive()
 {
     // We have to crawl our entire tree looking for any FrameViews that need
     // layout and make sure they are up to date.
     // Mac actually tests for intersection with the dirty region and tries not to
     // update layout for frames that are outside the dirty region.  Not only does this seem
     // pointless (since those frames will have set a zero timer to layout anyway), but
     // it is also incorrect, since if two frames overlap, the first could be excluded from the dirty
     // region but then become included later by the second frame adding rects to the dirty region
     // when it lays out.
@@ skipping 1439 matching lines @@
 
 LayoutObject* FrameView::viewportLayoutObject()
 {
     if (Document* document = frame().document()) {
         if (Element* element = document->viewportDefiningElement())
             return element->layoutObject();
     }
     return nullptr;
 }
 
+void FrameView::collectFrameTimingRequestsRecursive(
+    GraphicsLayerFrameTimingRequests& graphicsLayerTimingRequests)

[chrishtr, 2015/05/08 16:52:04]

Put this on the same line. Blink has no 80-column restriction..

[MikeB, 2015/05/08 18:37:34]

Done.

+{
+    for (Frame* frame = m_frame.get(); frame;
+        frame = frame->tree().traverseNext(m_frame.get())) {

[chrishtr, 2015/05/08 16:52:04]

same here IMO. Consider reducing lines in the rest of this method also.

[MikeB, 2015/05/08 18:37:34]

Done.

+        if (!frame->isLocalFrame())
+            continue;
+        LocalFrame* localFrame = toLocalFrame(frame);
+        LayoutRect rect = localFrame->contentLayoutObject()->viewRect();
+
+        DeprecatedPaintLayer::mapRectToPaintInvalidationBacking(
+            localFrame->contentLayoutObject(),
+            localFrame->contentLayoutObject()->containerForPaintInvalidation(),
+            rect);
+
+        const DeprecatedPaintLayer* layer = localFrame->contentLayoutObject()
+            ->enclosingLayer()
+            ->enclosingLayerForPaintInvalidationCrossingFrameBoundaries();

[chrishtr, 2015/05/08 16:52:04]

containerForPaintInvalidation() is the same as this, you can reuse the
computation from line 4033. In fact this method should probably be removed,
I'll make a note for myself.

[MikeB, 2015/05/08 18:37:34]

Done.

+        const GraphicsLayer* graphicsLayer = !layer ? nullptr :
+            layer->graphicsLayerBacking();
+
+        if (!graphicsLayer)
+            continue;
+
+        GraphicsLayerFrameTimingRequests::iterator requestIterator =
+            graphicsLayerTimingRequests.find(graphicsLayer);

[chrishtr, 2015/05/08 16:52:04]

I think you can just write:

graphicsLayerTimingRequests[graphicsLayer].push_back(std::make_pair(frame->frameID(),
enclosingIntRect(rect)));

the [] operator on a hash map makes a value if there was previously no entry
with the given key.

[MikeB, 2015/05/08 18:37:34]

error: no viable overloaded operator[] for type
'GraphicsLayerFrameTimingRequests' (aka 'HashMap<const blink::GraphicsLayer *,
std::vector<std::pair<int64_t, WebRect> > >')

I think that might be true of hash_map but not HashMap.

Although it looks like HashMap::add will do nothing if the key is already
present, so I think I can get away with the one-liner:

graphicsLayerTimingRequests.add(graphicsLayer,std::vector<std::pair<int64_t,
WebRect>>()).storedValue->value.push_back(std::make_pair(frame->frameID(),
enclosingIntRect(rect)));

+        std::vector<std::pair<int64_t, WebRect>> *graphicsLayerTimingRects;
+        if (requestIterator == graphicsLayerTimingRequests.end()) {
+            graphicsLayerTimingRects = &graphicsLayerTimingRequests.add(
+                graphicsLayer,
+                std::vector<std::pair<int64_t, WebRect>>()).storedValue->value;
+        } else {
+            graphicsLayerTimingRects = &requestIterator->value;
+        }
+        graphicsLayerTimingRects->push_back(
+            std::make_pair(frame->frameID(), enclosingIntRect(rect)));
+
+        if (frame != m_frame.get()) {

[chrishtr, 2015/05/08 16:52:04]

Factor into two methods, one which does the recursion and one which fills in
hash map values. There are other recursions just like that in this file, such as
invalidateTreeIfNeededRecursive that you can copy the pattern from.

[MikeB, 2015/05/08 18:37:34]

Done.

+            if (FrameView* view = localFrame->view()) {
+                view->collectFrameTimingRequestsRecursive(
+                    graphicsLayerTimingRequests);
+            }
+        }
+    }
+}
+
 } // namespace blink