Bug 121874

Summary: Tiled drawing should not imply threaded scrolling
Product: WebKit Reporter: Tim Horton <thorton>
Component: Layout and RenderingAssignee: Tim Horton <thorton>
Severity: Normal CC: andersca, bdakin, commit-queue, esprehn+autocc, glenn, kondapallykalyan, sam, simon.fraser, webkit-bug-importer
Priority: P2 Keywords: InRadar
Version: 528+ (Nightly build)   
Hardware: Unspecified   
OS: Unspecified   
Bug Depends on:    
Bug Blocks: 121859    
Description Flags
patch sam: review+

Description Tim Horton 2013-09-24 15:48:26 PDT
They should be separate settings (though threaded scrolling will required tiled drawing, I think).

Needed to separate/reduce the layout test churn for 121859 and for general sanity. We can make layout tests use threaded scrolling as well at a future date.
Comment 1 Radar WebKit Bug Importer 2013-09-24 15:49:11 PDT
Comment 2 Tim Horton 2013-09-25 11:27:29 PDT
This is kind of messy, because lots of things in WebCore depend on the existence of a scrolling coordinator to mean “do what I should do if we’re using tiled drawing” (use a tiled backing for the root, use the shadow and ‘linen’ background view, etc.).

I can either

a) plumb some new thing down to WebCore that means ‘we’re using tiled drawing’; whether that be a setting or whatever (?)

b) do this at the same time as ‘remove-DrawingAreaImpl and always use tiled drawing’, which would mean that we could just (for Mac) always do these things
Comment 3 Tim Horton 2013-09-25 18:07:54 PDT
Created attachment 212646 [details]
Comment 4 Anders Carlsson 2013-09-25 19:04:25 PDT
Comment on attachment 212646 [details]

View in context: https://bugs.webkit.org/attachment.cgi?id=212646&action=review

> Source/WebKit2/WebProcess/WebPage/DrawingArea.h:92
> +    virtual bool shouldUseTiledBackingForFrame(const WebCore::Frame&) { return false; }

Maybe this should take a frame view?
Comment 5 Tim Horton 2013-09-26 10:33:35 PDT