[Webkit-unassigned] [Bug 7259] New: Pages in bugzilla scroll slowly when obsolete attachments are present

[bugzilla-daemon at opendarwin.org]

http://bugzilla.opendarwin.org/show_bug.cgi?id=7259

           Summary: Pages in bugzilla scroll slowly when obsolete
                    attachments are present
           Product: WebKit
           Version: 420+ (nightly)
          Platform: Macintosh
        OS/Version: Mac OS X 10.0
            Status: NEW
          Severity: normal
          Priority: P2
         Component: Layout and Rendering
        AssignedTo: webkit-unassigned at opendarwin.org
        ReportedBy: hyatt at apple.com


opacity basically has two major performance problems.

The first problem can be traced to mustExamineRenderer in RenderLayer.cpp,
which basically gives up if you're an inlineFlow, meaning even when inline
flows are totally off-screen, we still begin/end transparency layers for them
(and try to paint them).

The second problem is that there's no clip set when we begin/end transparency
layers, and so they're always enormous.  We need to try to set up a clip to
limit the size.

I think a good way to fix mustExamineRenderer is to completely eliminate it and
to also eliminate layer bounds.  We should replace the concept of layer bounds
with an actual "bounding box" IntRect that should be specifically used for hit
testing and for painting of the layer.  Then places that really cared about the
use of x/w/width/height of the render object could use that instead of
x/y/width/height vals in the layer.


-- 
Configure bugmail: http://bugzilla.opendarwin.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug, or are watching the assignee.