Changeset 80292 in webkit

Timestamp:

Mar 3, 2011 3:33:58 PM (13 years ago)

Author:

Adam Roben

Message:

Don't try to paint outside the page's bounds

When the page is resized smaller, we would allocate a ShareableBitmap at the old, larger
size, even though we only needed to paint at the new, smaller size.

The assertion added in this patch will fire during the WebKit2/ResizeViewWhileHidden API
test if this fix gets broken in the future.

Fixes <​http://webkit.org/b/55715> DrawingAreaImpl allocates more memory than necessary when
the page is resized smaller

Reviewed by Anders Carlsson.

• WebProcess/WebPage/DrawingAreaImpl.cpp:

(WebKit::DrawingAreaImpl::updateBackingStoreState): Update our dirty region even if painting
is suspended (but still refrain from updating it when in accelerated compositing mode).
Rather than unite our existing dirty region with the page's new bounds, overwrite our dirty
region with the page's new bounds. This prevents us from accumulating a dirty region that is
larger than the page in the case where the page is being resized smaller.
(WebKit::DrawingAreaImpl::display): Added an assertion that we're not trying to paint
outside of the page's bounds.

Location:

trunk/Source/WebKit2

Files:

• ChangeLog (modified) (1 diff)
• WebProcess/WebPage/DrawingAreaImpl.cpp (modified) (2 diffs)

trunk/Source/WebKit2/ChangeLog

@@ +1 @@
+2011-03-03  Adam Roben  <aroben@apple.com>
+
+        Don't try to paint outside the page's bounds
+
+        When the page is resized smaller, we would allocate a ShareableBitmap at the old, larger
+        size, even though we only needed to paint at the new, smaller size.
+
+        The assertion added in this patch will fire during the WebKit2/ResizeViewWhileHidden API
+        test if this fix gets broken in the future.
+
+        Fixes <http://webkit.org/b/55715> DrawingAreaImpl allocates more memory than necessary when
+        the page is resized smaller
+
+        Reviewed by Anders Carlsson.
+
+        * WebProcess/WebPage/DrawingAreaImpl.cpp:
+        (WebKit::DrawingAreaImpl::updateBackingStoreState): Update our dirty region even if painting
+        is suspended (but still refrain from updating it when in accelerated compositing mode).
+        Rather than unite our existing dirty region with the page's new bounds, overwrite our dirty
+        region with the page's new bounds. This prevents us from accumulating a dirty region that is
+        larger than the page in the case where the page is being resized smaller.
+        (WebKit::DrawingAreaImpl::display): Added an assertion that we're not trying to paint
+        outside of the page's bounds.
+
 2011-03-03  Maciej Stachowiak  <mjs@apple.com>
 

trunk/Source/WebKit2/WebProcess/WebPage/DrawingAreaImpl.cpp

@@ -265 +265 @@
         // will be sent back in the DidUpdateBackingStoreState message.
         m_layerTreeHost->setShouldNotifyAfterNextScheduledLayerFlush(false);
-    }
+    } else
+        m_dirtyRegion = m_webPage->bounds();
 
     if (m_isPaintingSuspended || m_layerTreeHost)
         updateInfo.viewSize = m_webPage->size();
     else {
-        m_dirtyRegion.unite(m_webPage->bounds());
-
         // The display here should not cause layout to happen, so we can't enter accelerated compositing mode here.
         display(updateInfo);
@@ -450 +449 @@
 
     IntRect bounds = m_dirtyRegion.bounds();
+    ASSERT(m_webPage->bounds().contains(bounds));
 
     RefPtr<ShareableBitmap> bitmap = ShareableBitmap::createShareable(bounds.size());