[webkit-reviews] review granted: [Bug 69796] Support creating composited layers for fixed position elements : [Attachment 112035] Patch

[bugzilla-daemon at webkit.org]

Simon Fraser (smfr) <simon.fraser at apple.com> has granted Vangelis Kokkevis
<vangelis at chromium.org>'s request for review:
Bug 69796: Support creating composited layers for fixed position elements
https://bugs.webkit.org/show_bug.cgi?id=69796

Attachment 112035: Patch
https://bugs.webkit.org/attachment.cgi?id=112035&action=review

------- Additional Comments from Simon Fraser (smfr) <simon.fraser at apple.com>
View in context: https://bugs.webkit.org/attachment.cgi?id=112035&action=review


r+ but I'd prefer m_compositingNeedsUpdate and m_compositingDependsOnGeometry
be combined.

> Source/WebCore/rendering/RenderLayerCompositor.cpp:1505
> +    // position:fixed elements that create their own stacking context (e.g.
have an explicit z-index,
> +    // opacity, transform) can get their own composited layer.

Would be nice to explain here why you need the stacking context check.

> Source/WebCore/rendering/RenderLayerCompositor.h:303
> +    mutable bool m_compositingNeedsUpdate;

This has a similar role to m_compositingDependsOnGeometry; can they be combined
into one "composting must be updated after layout"?