[Openal] Max number of sources (and legit id values) for each OpenAL implementation

[Daniel PEACOCK]

Hi,

Those numbers are correct for Generic Hardware and Generic Software.

Creative ships various other OpenAL devices that support between 60 and 128
sources.

We used to ship an OpenAL implementation that would return 0 for a valid
Source ID.  However we found some problems in the field with games that
were doing things like ...

if (sourceID)
      // found valid source do something with it

instead of ...

if (alIsSource(sourceID))
      // found valid source do something with it

So we changed our implementations to stop returning an id of 0.  However,
as you say, the spec. does not disallow Source IDs of 0 - so code should
always use alIsSource() to validate a Source ID.

Dan
Creative Labs (UK) Ltd.

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                                       [Openal] Max number of sources (and 
             07/21/2009 09:35          legit id values) for each           
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Hi, I am writing some stuff about OpenAL and I would like to get my
facts straight. Can people verify my information about the maximum
number of sources?

Creative Labs:
I recall seeing this in an old mailing list thread.
Generic Software: 256
Generic Hardware: 16-64


OpenAL Soft:
>From the source code, I do see a hard coded value of 256, but there is
other conditional stuff in there so I'm thinking there might be other
potential values?


Mac OS X and iPhone OS:
>From the source code, it looks like the max you can request at a time
(to alGenSources) is 256. However, there doesn't seem to be anything
stopping you from making multiple calls to alGenSources of 256
sources. Probably not the intended behavior, but interesting.

Experimenting on the iPhone, the code seems to be the same here
because multiple calls of 256, give me unique source ids. (I haven't
been able to find the iPhone OpenAL source code.)


Are there any other implementations I'm forgetting?


Also, on this topic, do any implementations actually return 0 as a
valid id? I know the 1.1 spec doesn't reserve any value, but this has
always been a gotcha for me because in OpenGL, 0 is reserved.

Thanks,
Eric
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