Bug 168654 – [Win] WebView is not painting in accelerated compositing mode.

• Status: RESOLVED
• Resolution: FIXED
• Component: WebCore Misc.

[Per Arne Vollan]

The WebView window is black in accelerated compositing mode.

[Per Arne Vollan]

Created attachment 302257 [details]
Patch

[Per Arne Vollan]

rdar://problem/30515072

[Simon Fraser (smfr)]

Comment on attachment 302257 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=302257&action=review

> Source/WebCore/ChangeLog:3
> +        [Win] WebView is not painting in accelerated compositing mode.

Does this mean "When the web view paints, it is not making use of accelerated compositing", or "When accelerated compositing mode is on, the web view doesn't paint anything"?

> Source/WebCore/ChangeLog:9
> +        stops WevbView painting in accelerated mode.

WevbView. Why? Can you explain?

[Brent Fulgham]

Comment on attachment 302257 [details]
Patch

I think this is okay as a short-term fix, but we need to understand why this change broke Windows so badly. Can you please add a "FIXME" comment here, and file a Bugzilla to find/fix the underlying issue? r=me with that change.

[Per Arne Vollan]

(In reply to comment #3)
> Comment on attachment 302257 [details]
> Patch
>

Thanks for reviewing!
 
> View in context:
> https://bugs.webkit.org/attachment.cgi?id=302257&action=review
> 
> > Source/WebCore/ChangeLog:3
> > +        [Win] WebView is not painting in accelerated compositing mode.
> 
> Does this mean "When the web view paints, it is not making use of
> accelerated compositing", or "When accelerated compositing mode is on, the
> web view doesn't paint anything"?
> 

When accelerated compositing mode is on, the web view doesn't paint anything.

> > Source/WebCore/ChangeLog:9
> > +        stops WevbView painting in accelerated mode.
> 
> WevbView. Why? Can you explain?

It seems we have had a similar issue before:

https://bugs.webkit.org/show_bug.cgi?id=64808

[Brent Fulgham]

(In reply to comment #5)
> > > Source/WebCore/ChangeLog:9
> > > +        stops WevbView painting in accelerated mode.
> > 
> > WevbView. Why? Can you explain?
> 
> It seems we have had a similar issue before:
> 
> https://bugs.webkit.org/show_bug.cgi?id=64808

Gosh! We should really ask that Simon Fraser character what is going on here! ;-)

[Simon Fraser (smfr)]

So maybe the right fix is:

diff --git a/Source/WebCore/platform/graphics/ca/GraphicsLayerCA.cpp b/Source/WebCore/platform/graphics/ca/GraphicsLayerCA.cpp
index e7f3b879c0b1c3ce2317fff2296f24c6071ccb0c..6a3969ccc2627eeffad2ebff6c1b9e741bd51399 100644
--- a/Source/WebCore/platform/graphics/ca/GraphicsLayerCA.cpp
+++ b/Source/WebCore/platform/graphics/ca/GraphicsLayerCA.cpp
@@ -408,6 +408,7 @@ void GraphicsLayerCA::initialize(Type layerType)
     }
     m_layer = createPlatformCALayer(platformLayerType, this);
     noteLayerPropertyChanged(ContentsScaleChanged);
+    noteLayerPropertyChanged(CoverageRectChanged);
 }
 
 GraphicsLayerCA::~GraphicsLayerCA()
diff --git a/Source/WebCore/platform/graphics/ca/GraphicsLayerCA.h b/Source/WebCore/platform/graphics/ca/GraphicsLayerCA.h
index 07b6afaad4fe2ae568e7faedb62fda0e73364e19..72da30fa9ca24ab6fccfaafe0d79a56bc4c058fa 100644
--- a/Source/WebCore/platform/graphics/ca/GraphicsLayerCA.h
+++ b/Source/WebCore/platform/graphics/ca/GraphicsLayerCA.h
@@ -586,7 +586,7 @@ private:
 
     FloatSize m_pixelAlignmentOffset;
 
-    LayerChangeFlags m_uncommittedChanges { CoverageRectChanged };
+    LayerChangeFlags m_uncommittedChanges { 0 };
     bool m_isCommittingChanges { false };
 };
 
Can you try that?

[Simon Fraser (smfr)]

Also, did we not detect this failure because EWS doesn't run Windows tests, or something else?

[Per Arne Vollan]

Committed <https://trac.webkit.org/changeset/212730>

[Per Arne Vollan]

(In reply to comment #8)
> Also, did we not detect this failure because EWS doesn't run Windows tests,
> or something else?

Yes, we hope to get EWS running on Windows soon :)

[Per Arne Vollan]

(In reply to comment #7)
> So maybe the right fix is:
> 
> diff --git a/Source/WebCore/platform/graphics/ca/GraphicsLayerCA.cpp
> b/Source/WebCore/platform/graphics/ca/GraphicsLayerCA.cpp
> index
> e7f3b879c0b1c3ce2317fff2296f24c6071ccb0c..
> 6a3969ccc2627eeffad2ebff6c1b9e741bd51399 100644
> --- a/Source/WebCore/platform/graphics/ca/GraphicsLayerCA.cpp
> +++ b/Source/WebCore/platform/graphics/ca/GraphicsLayerCA.cpp
> @@ -408,6 +408,7 @@ void GraphicsLayerCA::initialize(Type layerType)
>      }
>      m_layer = createPlatformCALayer(platformLayerType, this);
>      noteLayerPropertyChanged(ContentsScaleChanged);
> +    noteLayerPropertyChanged(CoverageRectChanged);
>  }
>  
>  GraphicsLayerCA::~GraphicsLayerCA()
> diff --git a/Source/WebCore/platform/graphics/ca/GraphicsLayerCA.h
> b/Source/WebCore/platform/graphics/ca/GraphicsLayerCA.h
> index
> 07b6afaad4fe2ae568e7faedb62fda0e73364e19..
> 72da30fa9ca24ab6fccfaafe0d79a56bc4c058fa 100644
> --- a/Source/WebCore/platform/graphics/ca/GraphicsLayerCA.h
> +++ b/Source/WebCore/platform/graphics/ca/GraphicsLayerCA.h
> @@ -586,7 +586,7 @@ private:
>  
>      FloatSize m_pixelAlignmentOffset;
>  
> -    LayerChangeFlags m_uncommittedChanges { CoverageRectChanged };
> +    LayerChangeFlags m_uncommittedChanges { 0 };
>      bool m_isCommittingChanges { false };
>  };
>  
> Can you try that?

Thanks! Yes, I will try this in https://bugs.webkit.org/show_bug.cgi?id=168666.