Oolite Bulletins

1. Does Oolite require Pulseaudio?
2. If not, can it be set up to use Alsa?

1. Yes, If you install the .package version.
2. If you don't want to install PulseAudio you can
hide the oolite's libespeak library as described in this post.

EDIT(26/Jul/2010): Oolite 1.74.2 does not have PulseAudio dependency.
PulseAudio is just an alternative. Read here.

Expression 'snd_pcm_hw_params_set_buffer_size_near( pcm, hwParams, &lowLatency )' failed in 'src/hostapi/alsa/pa_linux_alsa.c', line: 415

I get the above (and no sound) - any ideas?

Sorry here's the whole message:
Expression 'snd_pcm_hw_params_set_buffer_size_near( pcm, hwParams, &lowLatency )' failed in 'src/hostapi/alsa/pa_linux_alsa.c', line: 415
Expression 'parameters->channelCount <= maxChans' failed in 'src/hostapi/alsa/pa_linux_alsa.c', line: 916
Expression 'ValidateParameters( outputParameters, hostApi, StreamDirection_Out )' failed in 'src/hostapi/alsa/pa_linux_alsa.c', line: 1134
Expression 'parameters->channelCount <= maxChans' failed in 'src/hostapi/alsa/pa_linux_alsa.c', line: 916
Expression 'ValidateParameters( outputParameters, hostApi, StreamDirection_Out )' failed in 'src/hostapi/alsa/pa_linux_alsa.c', line: 1134

Having read this and by googling the messages you posted,
this sounds like ALSA configuration.

Which distro are you on?

I am using Ubuntu 10.04LTS. Alsa is set up such that the default output encodes to Dolby Digital using the Alsa A52 plugin for output through S/PDIF.

I removed Pulseaudio after I could not get it to work with Alsa. Maybe the Simple DirectMedia Layer is having the same problem as Pulseaudio? I did manage to get some speech just no music or sound effects in Oolite.

Removing PulseAudio is a delicate task.
Please, read this on how to elegantly disable it.

I presume you have already renamed the
[/usr or ~/.local]/lib/Oolite/oolite-deps/lib/libespeak.so.2
[/usr or ~/.local]/lib/Oolite/oolite-deps/lib/libespeak.so.1
in order for oolite not search PulseAudio.

EDIT: Corrected typo error of libespeak version.

Ok cool thanks. I shall try that when I get home.

I did that and while it is certainly a much tidier way to get rid of Pulseaudio it did not solve my problem.

After much playing around I found in .asoundrc:
pcm.Filter_RateConvert {
type plug
# type rate
slave {
pcm "Filter_Duplex"
rate 48000
}
}
works, but if you uncomment the "type rate" line and comment the "type plug" line, it doesn't work. If you bypass that filter ie. use Filter_Duplex as the pcm.default, the Oolite music tone is lower.

I'm glad you made it.

With a lot of trial and error and some help from the Pulseaudio devs, I managed to get A52 (Dolby Digital) encoding working through Pusleaudio in Lucid. If you're interested, see:
https://bugs.launchpad.net/pulseaudio/+bug/348353