Changeset 172534 in webkit

Timestamp:

Aug 13, 2014 1:21:31 PM (10 years ago)

Author:

Simon Fraser

Message:

[WK1] A fixed-position <img> may not show on page load
​https://bugs.webkit.org/show_bug.cgi?id=135893

Reviewed by Tim Horton.

Source/WebCore:

A position:fixed image could fail to display because we didn't make a
compositing layer for it under some circumstances. This can happen if
RenderLayerCompositor::requiresCompositingForPosition() runs before the
image is loaded, in which cause the layer is zero-sized, so does not get
composited.

When the image loads, there was no code path that ensured that compositing
would be re-evaluated (unlike size changes due to style updates). Fix by
having RenderLayer::contentChanged() also check for ImageChanged.

Test: compositing/fixed-image-loading.html

• rendering/RenderLayer.cpp:

(WebCore::RenderLayer::contentChanged):

LayoutTests:

Test with a position:fixed image. Note that the test has to force layout
early on to test the bug.

• compositing/fixed-image-loading-expected.txt: Added.
• compositing/fixed-image-loading.html: Added.

Location:

trunk

Files:

• LayoutTests/ChangeLog (modified) (1 diff)
• LayoutTests/compositing/fixed-image-loading-expected.txt (added)
• LayoutTests/compositing/fixed-image-loading.html (added)
• Source/WebCore/ChangeLog (modified) (1 diff)
• Source/WebCore/rendering/RenderLayer.cpp (modified) (1 diff)

trunk/LayoutTests/ChangeLog

@@ +1 @@
+2014-08-13  Simon Fraser  <simon.fraser@apple.com>
+
+        [WK1] A fixed-position <img> may not show on page load
+        https://bugs.webkit.org/show_bug.cgi?id=135893
+
+        Reviewed by Tim Horton.
+        
+        Test with a position:fixed image. Note that the test has to force layout
+        early on to test the bug.
+
+        * compositing/fixed-image-loading-expected.txt: Added.
+        * compositing/fixed-image-loading.html: Added.
+
 2014-08-13  Zoltan Horvath  <zoltan@webkit.org>
 

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2014-08-13  Simon Fraser  <simon.fraser@apple.com>
+
+        [WK1] A fixed-position <img> may not show on page load
+        https://bugs.webkit.org/show_bug.cgi?id=135893
+
+        Reviewed by Tim Horton.
+        
+        A position:fixed image could fail to display because we didn't make a
+        compositing layer for it under some circumstances. This can happen if
+        RenderLayerCompositor::requiresCompositingForPosition() runs before the
+        image is loaded, in which cause the layer is zero-sized, so does not get
+        composited.
+        
+        When the image loads, there was no code path that ensured that compositing
+        would be re-evaluated (unlike size changes due to style updates). Fix by
+        having RenderLayer::contentChanged() also check for ImageChanged.
+
+        Test: compositing/fixed-image-loading.html
+
+        * rendering/RenderLayer.cpp:
+        (WebCore::RenderLayer::contentChanged):
+
 2014-08-13  Bem Jones-Bey  <bjonesbe@adobe.com>
 

trunk/Source/WebCore/rendering/RenderLayer.cpp

@@ -299 +299 @@
 void RenderLayer::contentChanged(ContentChangeType changeType)
 {
-    // This can get called when video becomes accelerated, so the layers may change.
-    if ((changeType == CanvasChanged || changeType == VideoChanged || changeType == FullScreenChanged) && compositor().updateLayerCompositingState(*this))
+    if ((changeType == CanvasChanged || changeType == VideoChanged || changeType == FullScreenChanged || changeType == ImageChanged) && compositor().updateLayerCompositingState(*this))
         compositor().setCompositingLayersNeedRebuild();