Bug 74851

Summary: [SVG] Pattern placement issues
Product: WebKit Reporter: Branimir Lambov <blambov>
Component: SVGAssignee: Nobody <webkit-unassigned>
Status: RESOLVED CONFIGURATION CHANGED    
Severity: Normal CC: bfulgham, jason.davies, pdr, zimmermann
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: Unspecified   
OS: Unspecified   
Attachments:
Description Flags
Testcase none

Description Branimir Lambov 2011-12-19 03:47:13 PST
Created attachment 119843 [details]
Testcase

This tests some pattern placement oddities caused by rounding.

The chessboard fill should end AT a field boundary, no cropped parts of a square
should be visible at any side of the pattern. The square boundaries should not
be affected by zooming.

The top square should be a one-pixel stroke with no bleed of red or green into 
the adjacent pixels.
Comment 1 Branimir Lambov 2011-12-19 03:56:09 PST
Firefox 8 and Opera 11.60 both display the pattern properly. Opera does bleed green in the rendering of the top square, Firefox does not have that problem.

The issue is caused by the rounding done in SVGImageBufferTools::createImageBuffer and lack of correction for the location of the buffer rectangle. The same type of problem appears in bug 73643, but patterns require a different treatment to avoid bleeding pixels under the pattern.
Comment 2 Jason Davies 2012-05-30 11:22:15 PDT
Confirmed in Safari 5.1.7.

See also:
- https://code.google.com/p/chromium/issues/detail?id=130326
- https://bugzilla.mozilla.org/show_bug.cgi?id=535185
Comment 3 Brent Fulgham 2022-07-15 15:02:16 PDT
Safari, Chrome, and Firefox all agree on rendering for this test case. I don't believe there is any remaining compatibility issue.