Bug 82609 – [Qt] Find zoomable area using area-based hit-testing

• Component: WebKit2
• Status: RESOLVED FIXED

[Allan Sandfeld Jensen]

The current implementation of tap-to-zoom uses a normal hit-testing and simply walks the DOM-tree to find a suitable zoomable area.

This fails to catch almost all cases of CSS layout that doesn't follow flow. A better solution is to use the areas returned by a rect-based hit-testing and returning the best zoomable area from the result.

[Allan Sandfeld Jensen]

Created attachment 134570 [details]
Patch

[Kenneth Rohde Christiansen]

Comment on attachment 134570 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=134570&action=review

lets look this over together tomorrow

> Source/WebCore/page/TouchAdjustment.cpp:101
> +    ASSERT(node->renderer());
> +    return node->renderer()->isBox();
> +}

What happens if it has a rotation transform? bounding box ?

> Source/WebCore/page/TouchAdjustment.cpp:120
> +    RenderBox* renderer = static_cast<RenderBox*>(node->renderer());

I believe there is a toRenderBox method

[Allan Sandfeld Jensen]

(In reply to comment #2)
> (From update of attachment 134570 [details])
> View in context: https://bugs.webkit.org/attachment.cgi?id=134570&action=review
> 
> lets look this over together tomorrow
> 
> > Source/WebCore/page/TouchAdjustment.cpp:101
> > +    ASSERT(node->renderer());
> > +    return node->renderer()->isBox();
> > +}
> 
> What happens if it has a rotation transform? bounding box ?
> 
Yes. This is similar to the current code. Also in this case bounding box is not an approximation. The bounding box is truly what we want to zoom to. I don't think UI's are ready for zoom and rotate :D

> > Source/WebCore/page/TouchAdjustment.cpp:120
> > +    RenderBox* renderer = static_cast<RenderBox*>(node->renderer());
> 
> I believe there is a toRenderBox method
Right!

[Allan Sandfeld Jensen]

Created attachment 134789 [details]
Patch

[Kenneth Rohde Christiansen]

Comment on attachment 134789 [details]
Patch

Nice improvement with layout tests!

[WebKit Review Bot]

Comment on attachment 134789 [details]
Patch

Clearing flags on attachment: 134789

Committed r112669: <http://trac.webkit.org/changeset/112669>

[WebKit Review Bot]

All reviewed patches have been landed.  Closing bug.