sdl patch for better pulseaudio support

[Pacho Ramos]

pulseaudio main maintainer made a patch for fixing sdl pulse plugin. Would be nice get it before Hardy final release

Thanks a lot

http://0pointer.de/public/sdl-pulse-rework.patch
http://0pointer.de/blog/projects/pa-plugin-for-sdl.html

[William Grant (wgrant)]

Those buffer changes definitely make it work a whole lot better, but what's the point of the other changes?

[Pacho Ramos (pacho)]

I am not sure, but maybe their autor will know it better, you can post a comment in http://0pointer.de/blog/projects/pa-plugin-for-sdl.html (If you don't have time I can do that if you prefer)

Thanks

[Daniel T Chen (crimsun)]

Yes, we should get this in before release.

[Scott Kitterman (kitterman)]

Ack from motu-release.

[Scott Kitterman (kitterman)]

But it's in Main, so ubuntu-release needs to look at it.

[Pacho Ramos (pacho)]

This causes a lot of problems in sdl based games, for example, I have just installed pingus and I cannot hear music (it is played too low and worse).

[OliFre (freyermuth)]

Temporary workaround:
Remove "libsdl1.2debian-pulseaudio" and replace with "libsdl1.2debian-all". However, this will bypass PulseAudio. I'm looking forward to a fix!

[Dan Ziemba (zman0900)]

I downloaded the source and applied the patch to try it out, and it works great. Now all the SDL games I have tried play great through Pulse, no more skipping, jerky audio. The patched deb is in my PPA if you want to try it yourself.

deb http://ppa.launchpad.net/zman0900/ubuntu hardy main
deb-src http://ppa.launchpad.net/zman0900/ubuntu hardy main

[OliFre (freyermuth)]

Confirmed to work! Thank you very much, now I can play multiple things at the same time again - finally.

[Martin Pitt (pitti)]

Luke, can you please take a look at this? Thanks!

[Luke Yelavich (themuso)]

Once the useless indent changes are removed from the patch, the code that is actually changed makes sense in terms of improved functionality. With ubuntu-release's blessing, I'll prepare an SRUp upload for this package. I will do some local testing in the meantime to see if performance is in fact improved.

[Luke Yelavich (themuso)]

Pacho, this issue is not related to the music not fully playing in pingus. Planetpenguin-racer has the same problem. It is something to do with MIDI music playback and SDL.

[Luke Yelavich (themuso)]

Before I go ahead and get things ready for an SRU, does anybody know of an SDL based application that has very bad sound when using the original pulseaudio SDL package from hardy? I've found one or two where one can hear pops and clicks, but something a bit noticable for testing purposes would be preferable, thanks.

[Dan Ziemba (zman0900)]

A few I've noticed have been Urban Terror, World of Padman, Neverputt, and Frozen Bubble. They all seem fine for me now after applying the patch.

[Manuel Schmid (fliegenderfrosch)]

I got pretty bad sound quality with frozen-bubble and libsdl1.2debian-pulseaudio. The packages from the PPA mentioned above fixed the problem for me.

[Jeremy Visser (jeremy-visser)]

OpenArena and X-Moto give bad sound for me here when running through PulseAudio.

I'm currently compiling with the patch to see if it fixes it.

[Jeremy Visser (jeremy-visser)]

Whoa, what a difference! As-is, the patch makes the sound much, _much_ clearer.

[Pacho Ramos (pacho)]

Other option could be check fedora's src.rpm, seems that they are using esd-emulation because:

# Temporary hack: Use pulseaudio via esd so SDL apps don't lock up when they
# attempt to use ALSA via pulseaudio. This will be removed when...
# 1) SDL's pulseaudio support is working natively without problems
# 2) it conditionally switches to pulseaudio or ALSA automatically

ftp://ftp.free.fr/pub/Distributions_Linux/Fedora/development/source/SRPMS/SDL-1.2.13-4.fc10.src.rpm

But they are also applying attached patch

This should be fixed at least for 8.04.1 :-/

Thanks a lot

[Brice Terzaghi (terzag)]

I've recently encountered problems with PulseAudio in SDL apps. My current setting is to install libsdl-all and setting SDL_AUDIODRIVER depending on the application I want to launch (thus, I have to launch them manually or create scripts, as with libsdl-all ALSA supercedes ESD/PulseAudio and it makes applications crash).
For the apps I've checked :
- ScummVM needs SDL_AUDIODRIVER set to "pulse" (no sound with "esd")
- Warsow needs "esd" (laggy sound with "pulse")
- a Wolfenstein Enemy Territory executable patched to use SDL needs "esd" too (same laggy sound problem than Warsow)
- I'm not sure it uses SDL, but the PCSX Playstation emulator randomly outputs sound, whichever SDL_AUDIODRIVER setting I use (if it's not SDL, then it seems to have problems with PulseAudio).

[Steve Langasek (vorlon)]

Since this appears to be a request for an SRU, subscribing the Ubuntu SRU team instead of ubuntu-release.

Luke, is this already fixed in intrepid?

[Luke Yelavich (themuso)]

Yes, this is fixed in intrepid. I'll prepare an SRU for this shortly.

[Jordan Erickson (lns)]

This could possibly affect LTSP users via https://bugs.launchpad.net/ubuntu/+source/tuxpaint/+bug/269082 - I'm not marking as a duplicate, but it sounds like it could be one.

[Jordan Erickson (lns)]

Nope - scratch that last comment. Doesn't help with that bug.

[Luke Yelavich (themuso)]

Fixed in Jaunty if not intrepid as well

[Simon Chemouil (simon-chemouil)]

I am using Jaunty (fully updated) and I still have the problem of "scratchy" sound when playing SDL games with libsdl1.2debian-pulseaudio (even with the patch, I built it and checked the patch was applied). libsdl1.2debian-esd is laggy, and when using libsdl1.2debian-alsa since I updated to Jaunty, the sound thread ends up being deadlocked because the device becomes busy randomly...

[Geoffrey Pursell (geoffp)]

I've still got this, too. I still have unacceptably choppy sound on 9.04 as of this moment. I am trying to get sound out of mess & mame by setting $SDL_AUDIODRIVER=pulse.

Setting to oss and using padsp in front produces silence, and setting to esd produces serious latency.

[Geoffrey Pursell (geoffp)]

A half-workaround is to stick this at the bottom of my .profile:

export SDL_AUDIODRIVER="alsa"
export AUDIODEV=plug:pulse

But that come at too high a cost; doing that pegs one of my cores at 100% and the other at 40%.

[Luke Yelavich (themuso)]

Have you amde sure you have libsdl1.2debian-pulseaudio installed?

[Geoffrey Pursell (geoffp)]

I had libsdl1.2debian-pulseaudio installed at first, and presently libsdl1.2debian-all, for testing purposes.

[Geoffrey Pursell (geoffp)]

The only workaround that works for me in all cases is to use:

export SDL_AUDIODRIVER="alsa"
export AUDIODEV=hw:0

and then launch every SDL app that needs sound with pasuspender. Ack.

[Sebastien Bacher (seb128)]

Is that still an issue? Luke are you still working on it?