Bug 112989 – [wk2] Page Overlays: Don't create backing store until the client asks us to paint

• Component: WebKit2
• Status: RESOLVED FIXED

[Tim Horton]

There's no reason to create backing store for a page overlay if the client hasn't painted.

There are cases where a client will install a page overlay solely in order to get its mouse-tracking functionality, or who will paint much later - there's no reason to be hanging on to (and wasting time compositing) a layer or tiles for the entire size of the view if they're just transparent.

<rdar://problem/13355759>

[Tim Horton]

Created attachment 194411 [details]
patch

[Tim Horton]

Created attachment 194412

[Anders Carlsson]

Comment on attachment 194411 [details]
patch

View in context: https://bugs.webkit.org/attachment.cgi?id=194411&action=review

> Source/WebKit2/WebProcess/WebPage/mac/TiledCoreAnimationDrawingArea.mm:419
>      for (PageOverlayLayerMap::iterator it = m_pageOverlayLayers.begin(); it != end; ++it)
> -        it->value->setSize(viewSize);
> +        if (it->value->drawsContent())
> +            it->value->setSize(viewSize);

Please add braces around the for loop and put it->value in its own variable.

[Tim Horton]

http://trac.webkit.org/changeset/146551