[ut2003io] CPU Performance (was: Color depth)

[Ryan C. Gordon]

> frames go mostly down. I also just found out that reducing the audio
> channels to 8 or even 4 (I use 4 right now) increases the performance a
> LOT, almost as much as disabling the sound, while it still sounds very
> good mostly. Tweaks like this are great, even if they make the game a
> little bit less beautiful, they make it a lot more playable and fun.

For the Linux version, the openal.so we shipped is not optimized, since 
I didn't want to risk compatibility problems (hmmm, but I got that 
anyway with the Karma libs...look at all the K6 owners! Who'd've thought?).

It might be worth someone's time to build an openal with 
--enable-optimizations and a few other tweaks and compare framerates. On 
my dual 800MHz box, the OpenAL mixer thread was eating about 25-30% of 
the second CPU at a time, so I can imagine this is rough on a 
uniprocessor box.

Ogg Vorbis decoding goes in a third thread, but that generally seemed to 
take only 1-3% of the CPU...not worth optimizing, at least, not before 
someone gives OpenAL a good hard look.

Joe Valenzuela, the Linux OpenAL maintainer, sent me an email with some 
thoughts on OpenAL optimizations...I'll forward it to the list. if there 
are any tinkerers that care to experiment, I'd love to hear your results.

--ryan.