Bug 65056 – Enable fast path scrolling for composited iframes

• Component: New Bugs
• Status: RESOLVED FIXED

[Adrienne Walker]

Enable fast path scrolling for composited iframes

[Adrienne Walker]

Created attachment 101789 [details]
Patch

[James Robinson]

Comment on attachment 101789 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=101789&action=review

I'd like to see a test for the following testcase to see if it's OK to disregard the overlap test:

<iframe id="a" class="composited"></iframe>
<iframe id="b" class="noncomposited"></iframe>

where b overlaps a

i'm not 100% sure if b will be put into a composited layer in this case.  If it always will, then I agree it's fine to ignore the overlap test when considering whether to fast scroll inside a's FrameView.

> Source/WebCore/page/FrameView.cpp:1150
> +    if (contentsInCompositedLayer())

is it OK to ignore m_useSlowRepaints for composited layers?

[Collabora GTK+ EWS bot]

Comment on attachment 101789 [details]
Patch

Attachment 101789 [details] did not pass gtk-ews (gtk):
Output: http://queues.webkit.org/results/9226327

[Adrienne Walker]

(In reply to comment #2)
> (From update of attachment 101789 [details])
> View in context: https://bugs.webkit.org/attachment.cgi?id=101789&action=review
>
> > Source/WebCore/page/FrameView.cpp:1150
> > +    if (contentsInCompositedLayer())
> 
> is it OK to ignore m_useSlowRepaints for composited layers?

setUseSlowRepaints() is called in three places, all in RenderView.  All of which appear to be related to layers that have reflections, transforms, or transparency.  If you were doing this in software, I could see how these might cause blitting problems when scrolling.  However, if the layer has its own backing, none of these should be an issue.

I was tempted to rename this to setCannotBlitToWindow() to make this more clear.  I can also add more tests for all these cases.  :)

[Adrienne Walker]

Created attachment 102591 [details]
Patch

[Gustavo Noronha (kov)]

Comment on attachment 102591 [details]
Patch

Attachment 102591 [details] did not pass gtk-ews (gtk):
Output: http://queues.webkit.org/results/9284720

[Adrienne Walker]

Comment on attachment 102591 [details]
Patch

Taking off review until I can address that gtk issue.

[Adrienne Walker]

Created attachment 102661 [details]
Patch

[Adrienne Walker]

(In reply to comment #8)
> Created an attachment (id=102661) [details]
> Patch

Whoops, forgot the #if guard for accelerated compositing.  Thanks, ews bot!

[Adrienne Walker]

*** Bug 61806 has been marked as a duplicate of this bug. ***

[James Robinson]

Comment on attachment 102661 [details]
Patch

R=me

[Adrienne Walker]

Committed r92874: <http://trac.webkit.org/changeset/92874>