Bug 127469 - When a GC uses advanced and alphas the clipping is ignored in some cases.
Summary: When a GC uses advanced and alphas the clipping is ignored in some cases.
Status: RESOLVED FIXED
Alias: None
Product: Platform
Classification: Eclipse Project
Component: SWT (show other bugs)
Version: 3.2   Edit
Hardware: PC Windows XP
: P3 normal (vote)
Target Milestone: 3.3 M1   Edit
Assignee: Silenio Quarti CLA
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Reported: 2006-02-13 10:16 EST by Matthew Hatem CLA
Modified: 2006-07-20 11:31 EDT (History)
2 users (show)

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Attachments
SWT snippet to demonstrate the bug (4.84 KB, application/octet-stream)
2006-02-13 10:18 EST, Matthew Hatem CLA 		no flags Details
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Description Matthew Hatem CLA 2006-02-13 10:16:47 EST 
It appears that when alpha blending is enabled, TextLayout is not honoring the clip rect that I set on the offscreen GC.  But if I disable the alpha blending or diable the advanced rendering, it seems to work properly.
Comment 1 Matthew Hatem CLA 2006-02-13 10:18:14 EST 
Created attachment 34570 [details]
SWT snippet to demonstrate the bug
Comment 2 Florian Priester CLA 2006-07-16 21:40:56 EDT 
The reason for this is that TextLayout.draw uses some OS routines that
are not part of GDI+ (e.g. PatBlt, ScriptTextOut) and which therefore
ignore the GDI+ clipping region.
Comment 3 Silenio Quarti CLA 2006-07-17 11:23:30 EDT 
Thanks Florian! We have been working on some hacks to integrate Uniscribe and GDI+. Hang on. The problem is that GDI+ does not provide the same text layout support that Uniscribe does.
Comment 4 Felipe Heidrich CLA 2006-07-17 13:01:44 EDT 
Fixed in HEAD > 20060117.