Created attachment 102395 [details]
Wireframe rendered above foreground geometry (8xMSAA)
Black pixels along the wireframe of background geometry is rendered in front of foreground geometry (even UI). The wireframe isn't visible all the time but instead flickers as if there is some kind of race condition.
This is reproducible with all MSAA levels that can be set in the game (2x, 4x, 6x and 8x) - however with 2x and 4xMSAA, the wireframe is white instead of black. Wit MSAA disabled everything is rendered correctly.
Happens as of commit f6db414f3ca2d692f262e3f5a38d4fcedbdf4f4f, does not happen with mesa 10.2.2.
Bisecting blames commit 501fee2511a0a84303319a5e3deacf4959da5b08
Author: Marek Olšák <email@example.com>
Date: Tue May 6 13:48:11 2014 +0200
radeonsi: implement set_min_samples
This is how per-sample shading is enabled.
GPU: Radeon HD 7950 (OpenGL renderer string: Gallium 0.4 on AMD TAHITI)
LLVM compiled from svn today (r202464)
Created attachment 102396 [details]
How the scene is supposed to look
Created attachment 102397 [details]
Wireframe rendered above the user interface
Created attachment 102398 [details]
White wireframe with 4xMSAA
Created attachment 102399 [details] [review]
Does the attached patch fix the issue?
Yes, the attached patch fixes the issue for me.
Fixed by be536efe20d7d0969e6d5286fc488fcc1c403b6. Closing.