Waveform vsync test

Bug #1053141 reported by Daniel Schürmann on 2012-09-19
6
This bug affects 1 person
Affects Status Importance Assigned to Milestone
Mixxx
Low
Daniel Schürmann

Bug Description

Attached you will find a patch based on the mesa-demos glsync test.
It introduces a new waveform "GLVSyncTest" which toggle between red and white.

On my box I have awful flicker with the fglrx driver and better result with the radeon driver.

I have also noticed that the original glsync test flickers at the same moment the waveform flickers.

Related branches

Daniel Schürmann (daschuer) wrote :
Changed in mixxx:
assignee: nobody → Daniel Schürmann (daschuer)
status: New → In Progress

You mean between fglrx and the open source driver, I think it's called Gallium ? I wouldn't wonder if fglrx has problems since AMD does a bad job keeping their drivers working with the latest x version. I can test tomorrow if I see the same problem

Daniel Schürmann <email address hidden> wrote:

>Public bug reported:
>
>Attached you will find a patch based on the mesa-demos glsync test.
>It introduces a new waveform "GLVSyncTest" which toggle between red and white.
>
>On my box I have awful flicker with the fglrx driver and better result
>with the radeon driver.
>
>I have also noticed that the original glsync test flickers at the same
>moment the waveform flickers.
>
>** Affects: mixxx
> Importance: Undecided
> Assignee: Daniel Schürmann (daschuer)
> Status: In Progress
>
>--
>You received this bug notification because you are subscribed to Mixxx.
>Matching subscriptions: Mixxx-Bugs
>https://bugs.launchpad.net/bugs/1053141
>
>Title:
> Waveform vsync test
>
>Status in Mixxx:
> In Progress
>
>Bug description:
> Attached you will find a patch based on the mesa-demos glsync test.
> It introduces a new waveform "GLVSyncTest" which toggle between red and white.
>
> On my box I have awful flicker with the fglrx driver and better result
> with the radeon driver.
>
> I have also noticed that the original glsync test flickers at the same
> moment the waveform flickers.
>
>To manage notifications about this bug go to:
>https://bugs.launchpad.net/mixxx/+bug/1053141/+subscriptions

Daniel Schürmann (daschuer) wrote :

from the radeon man page:

Option "SwapbuffersWait" "boolean"
              This option controls the behavior of glXSwapBuffers and glXCopy‐
              SubBufferMESA calls by GL applications. If enabled, the calls
              will avoid tearing by making sure the display scanline is out‐
              side of the area to be copied before the copy occurs. If dis‐
              abled, no scanline synchronization is performed, meaning tearing
              will likely occur. Note that when enabled, this option can
              adversely affect the framerate of applications that render
              frames at less than refresh rate.

              The default value is on.

Conclusion:
It is required that we sync the waveform frames somehow to the vertical blank
to a void an unpredictable delay of up to 16,6 ms @ 60 Hz Displays

jus (jus) wrote :

A vsync test waveform type is included an is available by starting Mixxx with --developer.
https://github.com/mixxxdj/mixxx/commit/de0e4a3787c3fee8f277520c0b33f7a3469adb87

Changed in mixxx:
milestone: none → 1.12.0
importance: Undecided → Low
status: In Progress → Fix Committed
RJ Skerry-Ryan (rryan) on 2015-12-30
Changed in mixxx:
status: Fix Committed → Fix Released
To post a comment you must log in.
This report contains Public information  Edit
Everyone can see this information.

Other bug subscribers