Summary: | [Windows] Drawing Artifacts When Scrolling | ||||||||||
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Product: | WebKit | Reporter: | Brent Fulgham <bfulgham> | ||||||||
Component: | WebKit Misc. | Assignee: | Nobody <webkit-unassigned> | ||||||||
Status: | NEW --- | ||||||||||
Severity: | Normal | ||||||||||
Priority: | P2 | ||||||||||
Version: | 528+ (Nightly build) | ||||||||||
Hardware: | Unspecified | ||||||||||
OS: | Unspecified | ||||||||||
Attachments: |
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Description
Brent Fulgham
2011-06-30 11:30:53 PDT
Created attachment 99343 [details]
Example redraw problem
User is hovering over 'Mass Recovery (%)', but the old selection ('Rh Conformation Plot y-intercept') is mostly still visible, with only the region under the text above the cell being redrawn.
The problem does not seem to happen (or is at least very hard to reproduce) when interacting with the region at the top of the page (i.e., without scrolling). If you shrink the browser window, such that the bottom scrollbar is always active, the problem also seems to go away. There might be some issue of scrollbar size not being properly accounted for in the display logic. Created attachment 99347 [details]
ZIP containing the HTML/CSS/JavaScript code to demonstrate the problem.
Created attachment 99350 [details]
ZIP containing the HTML/CSS/JavaScript code to demonstrate the problem.
Updated ZIP without security settings.
This example does not seem to trigger a problem under the current shipping version of Safari on Mac OS X (10.6.8) Part of the problem seems to be the modification of the rect size (see the JavaScript routine 'adjustSelector', where the right-hand boundary of the rect is increased by the size of a button image (not used in the example). It seems that when this is performed on a heading (which span the full width of the page), it forces the element width to extend beyond the page boundaries set during the initial layout. This causes the scrollbar to pop-in on the bottom of the page. At that point, the layout logic seems to get confused and the repaint problems start happening. A workaround for now is to not increase the right-hand size of the rect, which prevents the last-minute scroll bar addition. When I make that change, I no longer get drawing artifacts. |