Changeset 135921 in webkit

Timestamp:

Nov 27, 2012 2:23:24 PM (11 years ago)

Author:

Alexandru Chiculita

Message:

[CSS Regions] Elements using transforms are not repainted correctly when rendered in a region
​https://bugs.webkit.org/show_bug.cgi?id=102826

Reviewed by David Hyatt.

Source/WebCore:

When the page is composited, all the elements will have a composited repaint container. In that case we will
never catch the repaints in the RenderFlowThread, but they will go directly to the RenderView.
There's a single case when the parent composited layer of an element inside the RenderFlowThread will get
its own repaints. That case only happens when the parent composited layer is also part of the same flow thread.
Right now compositing is disabled for elements inside the RenderFlowThread, so that case doesn't even happen yet.
That will be fixed in ​https://bugs.webkit.org/show_bug.cgi?id=84900.

Test: fast/repaint/region-painting-in-composited-view.html

• rendering/RenderObject.cpp:

(WebCore::RenderObject::containerForRepaint):

LayoutTests:

Added test file to check for repainting inside a RenderFlowThread when the page is in composited mode.

• fast/repaint/region-painting-in-composited-view-expected.html: Added.
• fast/repaint/region-painting-in-composited-view.html: Added.

Location:

trunk

Files:

• LayoutTests/ChangeLog (modified) (1 diff)
• LayoutTests/fast/repaint/region-painting-in-composited-view-expected.html (added)
• LayoutTests/fast/repaint/region-painting-in-composited-view.html (added)
• Source/WebCore/ChangeLog (modified) (1 diff)
• Source/WebCore/rendering/RenderObject.cpp (modified) (1 diff)

trunk/LayoutTests/ChangeLog

@@ +1 @@
+2012-11-27  Alexandru Chiculita  <achicu@adobe.com>
+
+        [CSS Regions] Elements using transforms are not repainted correctly when rendered in a region
+        https://bugs.webkit.org/show_bug.cgi?id=102826
+
+        Reviewed by David Hyatt.
+
+        Added test file to check for repainting inside a RenderFlowThread when the page is in composited mode.
+
+        * fast/repaint/region-painting-in-composited-view-expected.html: Added.
+        * fast/repaint/region-painting-in-composited-view.html: Added.
+
 2012-11-27  Tony Chang  <tony@chromium.org>
 

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2012-11-27  Alexandru Chiculita  <achicu@adobe.com>
+
+        [CSS Regions] Elements using transforms are not repainted correctly when rendered in a region
+        https://bugs.webkit.org/show_bug.cgi?id=102826
+
+        Reviewed by David Hyatt.
+
+        When the page is composited, all the elements will have a composited repaint container. In that case we will
+        never catch the repaints in the RenderFlowThread, but they will go directly to the RenderView. 
+        There's a single case when the parent composited layer of an element inside the RenderFlowThread will get 
+        its own repaints. That case only happens when the parent composited layer is also part of the same flow thread.
+        Right now compositing is disabled for elements inside the RenderFlowThread, so that case doesn't even happen yet.
+        That will be fixed in https://bugs.webkit.org/show_bug.cgi?id=84900.
+
+        Test: fast/repaint/region-painting-in-composited-view.html
+
+        * rendering/RenderObject.cpp:
+        (WebCore::RenderObject::containerForRepaint):
+
 2012-11-27  Tony Chang  <tony@chromium.org>
 

trunk/Source/WebCore/rendering/RenderObject.cpp

@@ -1291 +1291 @@
 
     // If we have a flow thread, then we need to do individual repaints within the RenderRegions instead.
-    // Return the flow thread as a repaint container in order to create a chokepoint that allows us to change
+    // Return the flow thread as a repaint container in order to create a checkpoint that allows us to change
     // repainting to do individual region repaints.
-    // FIXME: Composited layers inside a flow thread will bypass this mechanism and will malfunction. It's not
-    // clear how to address this problem for composited descendants of a RenderFlowThread.
-    if (!repaintContainer && inRenderFlowThread())
-        repaintContainer = enclosingRenderFlowThread();
+    if (inRenderFlowThread()) {
+        RenderFlowThread* parentRenderFlowThread = enclosingRenderFlowThread();
+        // If we have already found a repaint container then we will repaint into that container only if it is part of the same
+        // flow thread. Otherwise we will need to catch the repaint call and send it to the flow thread.
+        if (!(repaintContainer && repaintContainer->inRenderFlowThread() && repaintContainer->enclosingRenderFlowThread() == parentRenderFlowThread))
+            repaintContainer = parentRenderFlowThread;
+    }
     return repaintContainer;
 }