Bug 73444 - wayland/weston EGL/GLESv2 - top portion of screen in fullscreen: vertices being clipped/flicker
Summary: wayland/weston EGL/GLESv2 - top portion of screen in fullscreen: vertices bei...
Status: RESOLVED MOVED
Alias: None
Product: Mesa
Classification: Unclassified
Component: Drivers/Gallium/r600 (show other bugs)
Version: 10.0
Hardware: x86-64 (AMD64) Linux (All)
: medium normal
Assignee: Default DRI bug account
QA Contact:
URL:
Whiteboard:
Keywords:
Depends on:
Blocks:
 
Reported: 2014-01-09 18:29 UTC by emiettin
Modified: 2019-09-18 19:12 UTC (History)
0 users

See Also:
i915 platform:
i915 features:

Attachments

Description emiettin 2014-01-09 18:29:50 UTC 
In fullscreen wayland/weston EGL/GLESv2 clients without X11 (as in weston launched from a tty), vertices ending up on the top 5-10% portion of the vertical screen space are being clipped (as in seemingly skipped altogether and disappearing), despite setting up an appropriate projection matrix + calling glViewport. This results in flickering sawtooth-like edges on the top of the screen area.

This effect doesn't show up
- in windowed mode 
- in screenshots (weston Super+s) 
- in screen capture (weston Super+r)
- while zoomed in using the weston Super+mwheel shortcut, or
- when using weston through X11.

Asking about this on #dri-devel on Freenode lead to the following hypothesis by pq:

12:30 < pq> so if super+s, or zoom, or having it in a window makes the problem go away, then the fundamental difference is likely that when weston composites, everything goes well, but when weston tries to scan out the client image directly, something breaks.

This occurs at least in mesa 9.2.x through git master.

setup:

Arch Linux x86_64 3.12.6-1, 
Radeon HD 5770 w/ {ati-dri, mesa, mesa-libgl}-9.2.5-1, -10.0.1-1, or -git
wayland-1.3.0-1, weston-1.3.1-2 or git.
Comment 1 Michel Dänzer 2014-01-10 02:12:57 UTC 
(In reply to comment #1)
> 12:30 < pq> so if super+s, or zoom, or having it in a window makes the
> problem go away, then the fundamental difference is likely that when weston
> composites, everything goes well, but when weston tries to scan out the
> client image directly, something breaks.

Yes, it sounds like when weston tries to scan out the client surfaces directly, you're intermittently seeing the wrong surface being scanned out, or the right surface at the wrong time.
Comment 2 GitLab Migration User 2019-09-18 19:12:29 UTC 
-- GitLab Migration Automatic Message --

This bug has been migrated to freedesktop.org's GitLab instance and has been closed from further activity.

You can subscribe and participate further through the new bug through this link to our GitLab instance: https://gitlab.freedesktop.org/mesa/mesa/issues/480.

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.