Bug 97777 – [Qt] Decide when to apply a scrolled position to the viewport based on the rect covered by the tiles

• Component: New Bugs
• Status: RESOLVED FIXED

[Jocelyn Turcotte]

[Qt] Decide when to apply a scrolled position to the viewport based on the rect covered by the tiles

[Jocelyn Turcotte]

Created attachment 165984 [details]
Patch

[Kenneth Rohde Christiansen]

Comment on attachment 165984 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=165984&action=review

> Source/WebCore/platform/graphics/TiledBackingStore.cpp:263
> +    m_coverRect = coverRect;
>      setKeepRect(keepRect);

Why not add a setCoverRect for completion sake...

> Source/WebCore/platform/graphics/TiledBackingStore.h:75
> +    IntRect coveredRect() const { return m_coverRect; }

Do you know that this is in fact covered? why not just call it coverRect() ? More might be covered than this. Also why are we not looking at visibleRect. coverRect could be mouch bigger than needed

[Jocelyn Turcotte]

(In reply to comment #2)
> > Source/WebCore/platform/graphics/TiledBackingStore.h:75
> > +    IntRect coveredRect() const { return m_coverRect; }
> 
> Do you know that this is in fact covered? why not just call it coverRect() ? More might be covered than this. Also why are we not looking at visibleRect. coverRect could be mouch bigger than needed

It's not covered at this point, and I'm renaming it to coverRect() and tileCoverRect() to reflect this. It is covered after syncCompositingState() has been called on each layer so I'll keep it named tileCoveredRect from that point.

What I want to know it, am I going to see any content at all if I scroll the viewport to this position, or just white/checkerboard? So the contract is that at least coverRect() will be covered, and that's what I need.

[Jocelyn Turcotte]

Created attachment 166012 [details]
Patch

Rename coveredRect to coverRect from WebCore up until the rendering is done and remove tile from e.g. tileCoveredRect.
Also add TiledBackingStore::setCoverRect

[Jocelyn Turcotte]

Committed r130031: <http://trac.webkit.org/changeset/130031>