Bug 101004

Summary: Line has wrong coordinates when viewport width is reduced
Product: Mesa Reporter: Ruslan Kabatsayev <b7.10110111>
Component: Drivers/DRI/i965Assignee: Intel 3D Bugs Mailing List <intel-3d-bugs>
Status: RESOLVED FIXED QA Contact: Intel 3D Bugs Mailing List <intel-3d-bugs>
Severity: normal    
Priority: medium    
Version: 13.0   
Hardware: Other   
OS: All   
Whiteboard:
i915 platform: i915 features:
Attachments: Test program

Description Ruslan Kabatsayev 2017-05-11 13:26:38 UTC 
Created attachment 131315 [details]
Test program

The attached test program draws a line. Its endpoint positions appear different between i965 driver and llvmpipe. In program's initial state, the bug is triggered. You can toggle the bug by pressing a key.

The bug triggers when glViewport is called with a width less than window width (namely, 0.6*windowWidth in the test).

glxinfo reports:
OpenGL renderer string: Mesa DRI Intel(R) Haswell Server 
OpenGL version string: 3.0 Mesa 13.0.6 (git-fcef88d)

Video controller from lspci:
Intel Corporation Xeon E3-1200 v3 Processor Integrated Graphics Controller (rev 06)

CPU name from /proc/cpuinfo:
Intel(R) Xeon(R) CPU E3-1226 v3 @ 3.30GHz
Comment 1 Kenneth Graunke 2017-05-11 15:55:39 UTC 
Please upgrade to Mesa 17.1.0 or at least Mesa 17.0.x.  I believe I fixed this in January, but the fixes never made it to the 13.0.x series.  Mesa 13.x is basically unsupported at this point.
Comment 2 Ruslan Kabatsayev 2017-05-11 16:48:56 UTC 
Is fixed indeed in 17.1.0-rc4.

Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.