[Openal] Mixing 2D and 3D sources

[Garin Hiebert]

> is there any good way of ensuring certain
> sound sources (such as the 2D sounds mentioned, and the streaming
> source used to play the music back) are always played as if they were
> right where the listener is ?
>   

Good news.  For the 2D sounds, they already won't get 3D spatialization 
under OpenAL.  Turning off distance attenuation for 3D sounds can be 
done by setting the distance model for a specific source to AL_NONE 
(there's no harm in doing that for a source with a multichannel buffer 
attached to it as well, if that's easier to implement).

Garin