[Openal-devel] Is 'offline-rendering' possible with OpenAL?

[Jason Daly]

zefir wrote:
> Hi all,
>
> after reading the API-docs and vainly searching the net, I hope someone
> could help me with this trivial question.
>
> What I need to know is, if it is possible to do 'offline-rendering' with
> OpenAL, i.e. not playing out the mixed samples but accessing them for
> further processing (like writing to disk or sending over the network).
>
> I plan to develop an internet voice-conference application where the
> participants are virtually located in the conference room and will receive
> individual audio streams mixed with respect to their position. The related
> mixer does not need to play out the samples but to send them to the related
> client.
>
> I thought OpenAL would be a good choice, but there seems to be no way to
> define something like a memory-context where the processed data can be
> grabbed instead of being send to an audio device.
>   

I don't think there is currently a way to do this directly in memory, 
but the OpenAL-Sample implementation has a rudimentary "waveout" device 
that dumps the mixed audio directly to disk.  It's pretty raw, so there 
is no way to specify the filename (the file will be named openal-X.wav, 
where X is some number that produces a non-existent filename) or the 
target path (I believe it goes to the current directory).

It may not be workable the way it is, but the backend code itself is 
fairly simple, so you may be able to adapt it for your purposes.

--"J"