Bug 100374

Summary: [Chromium] Repaint issues with subpixel stroke
Product: WebKit Reporter: Florin Malita <fmalita>
Component: SVGAssignee: Florin Malita <fmalita>
Status: RESOLVED WONTFIX    
Severity: Normal CC: bsalomon, krit, leviw, pdr, reed, schenney, zimmermann
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: Unspecified   
OS: Unspecified   
Attachments:
Description Flags
Repaint artifacts on Chromium. none

Florin Malita
Reported 2012-10-25 06:41:24 PDT
Created attachment 170627 [details] Repaint artifacts on Chromium. Chromium bug: http://code.google.com/p/chromium/issues/detail?id=156597 The attached test exhibits repaint "ghosting" on Chromium. Subpixel stroke widths trigger Skia's hairline optimization (treating the stroke width as == 1 and modulating the color components). Combined with subpixel positioning, this means that we may end up touching pixels outside the computed repaint rect. Mike mentioned he's considering addressing this in Skia if he can find a way that doesn't impact the hairline optimization. In the meantime, we could inflate the repaint rect by .5 when USE(SKIA) to make sure we're covering the stroke.
Attachments
Repaint artifacts on Chromium. (334 bytes, image/svg+xml)
2012-10-25 06:41 PDT, Florin Malita 		no flags
Details
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Stephen Chenney
Comment 1 2013-04-09 17:07:28 PDT
Marked LayoutTest bugs, bugs with Chromium IDs, and some others as WontFix. Test failure bugs still are trackable via TestExpectations or disabled unit tests.
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