[Openal] Transparently mixing many sounds

[Garin Hiebert]

> Is there a way to get at how many sources OpenAL is currently mixing? 
Yes, if you ask each source for its AL_SOURCE_STATE property and total 
up the number of sources that are in the AL_PLAYING state, you _might_ 
be getting back an accurate picture of how many sources are being 
mixed.  This isn't a question that should be relevant for an 
OpenAL-based audio engine, however.  In OpenAL, all sources that have 
been generated could be mixed at the same time -- OpenAL guarantees it.
> If not then I can use my higher-level API's internal queues, but I 
> don't yet know how accurate those are, so something lower-level would 
> be more desirable for now. :)
If you want to maintain the illusion of playing more sources than OpenAL 
can generate for you, this functionality has to be maintained at a level 
above OpenAL.

Garin