CVS Update (Linux audio - please test!)

SDL Development
1

Thanks to some feedback and a patch from the folks at OpenSound.com,
I’ve improved the Linux DSP audio driver. Could people test it and
see if it works and if it has the same latency as the old code?

You can get the latest CVS snapshot of SDL from:
http://www.libsdl.org/cvs.html

Changes:

  • Changed DSP audio driver to use blocking writes
  • Fixed possible dropout in DSP audio driver (thanks Hannu!)
  • Fixed DMA audio with some Linux sound card drivers

See ya!
-Sam Lantinga, Lead Programmer, Loki Software, Inc.

2

Sam Lantinga wrote:

Thanks to some feedback and a patch from the folks at OpenSound.com,
I’ve improved the Linux DSP audio driver. Could people test it and
see if it works and if it has the same latency as the old code?

You can get the latest CVS snapshot of SDL from:
http://www.libsdl.org/cvs.html

Changes:

  • Changed DSP audio driver to use blocking writes

Should this be a feature? Now the program hangs during start,
if another program is using the DSP. It it now not possible
to start the same application two times.

With the old version did it run, but without sound.

There must be atleast a function, if it is possible to open sound.

Bye,
Johns–
Become famous, earn no money, create music or graphics for FreeCraft

http://FreeCraft.Org - A free fantasy real-time strategy game engine
http://fgp.cjb.net - The FreeCraft Graphics Project

3

Should this be a feature? Now the program hangs during start,
if another program is using the DSP. It it now not possible
to start the same application two times.

Whoops, thank you very much. I’ll fix that. That’s why I announce
these kinds of changes. :slight_smile:

See ya!
-Sam Lantinga, Lead Programmer, Loki Software, Inc.

4
  • Changed DSP audio driver to use blocking writes

I thought this was changed last year to not use blocking writes, due to
buggy hardware drivers. Has this situation changed?

–ryan.

5
  • Changed DSP audio driver to use blocking writes

I thought this was changed last year to not use blocking writes, due to
buggy hardware drivers. Has this situation changed?

The folks at 4Front Technologies suggested that blocking writes are faster
at the driver level, and I believe most of the drivers have been fixed.
I enabled it in the CVS code to see if there was any improvement for end
users.

See ya,
-Sam Lantinga, Lead Programmer, Loki Software, Inc.

6

Should this be a feature? Now the program hangs during start,
if another program is using the DSP. It it now not possible
to start the same application two times.

With the old version did it run, but without sound.

Okay, I’ve fixed the code so that it does a non-blocking open even
when doing blocking writes.

I’ve also reverted to non-blocking writes… 'If it ain’t broke, don’t fix it"

See ya,
-Sam Lantinga, Lead Programmer, Loki Software, Inc.