[SDL] SDL & eee PC

[Rhythmic Fistman]

On 4/16/08, sdl-request at lists.libsdl.org <sdl-request at lists.libsdl.org> wrote:
>  From: "M-.-n" <nostromo at arkaos.net>
>  Hi there,
>
>  I've been struggling for a while trying to port a cross-plaform tracker
>  (using SDL on most platforms) to run smoothly on eee-PCs running
>  Xandros. I do believe the video API does affect the audio smoothness but
>  I have no way to test it. ALSA stutters a lot while 'dsp' is sort of ok,
>  excepts it drops a blank every minute or so. It's kind of frustrating
>  coz when I look at top, the process only taks 7% of the CPU :(
>
>  I was wondering if anybody would have been through the same issues or
>  experiences, and if someone knew a decent route (or example) to get a
>  SDL-based audio/gfx program to run properly on this machine.

Never tried "xandros", but SDL linux sound has given me problems
that I wasn't able to resolve. Here are my stream-of-consciousness
notes on it, maybe they'll help. If you figure something out, do tell
(I don't think I'd tried the dsp driver, so I'll give it a shot). For me the
important variables seemed to be buffer size and driver, I don't think
video has anything to do with it:

sound doesn't work out of the box with SDL 1.2.11 on ubuntu (vers?)

under parallels ubuntu (1.2.11). SDL_OpenAudio is failing with
the message "buffer size must be a power of 2". passing an "obtained" audio
spec doesn't help, fn fails just the same. making the buffer size a power
of 2 doesn't actually get you any output. however, setting SDL_AUDIODRIVER
to either "esd" or "alsa" does work and lifts the unknowable a priori power of 2
restriction.

"esd" can't do silence, clicks and seems to overflow with lots
of sounds. "alsa" seems doesn't have this problem. however killing the alsa
version with ctl-\ can cause a hellish racket (ctl-c no). Note: alsa asks
for fewer frames (esd doesn't), hence the spooner* code is working.
why doesn't the default driver work and which is it??

the non-functional default (on my ubuntu and ben's kubuntu) could be oss?

*this refers to the bit of code that handles the situation in which the
audio callback asks for fewer, or more samples than are ready.