OpenAL : alGenSources() problem
Author
Hi. I know that most people don''t use OpenAL but I''m hoping some people may know the problem that I am having.
Please don''t say "Use FMOD", I''m trying to learn a range of API''s to find out what I like best before sticking to one.
I''m making a game where I want a different sound source for each unit, so that it can make noises that originate from the unit. Problem is, I have about 40 units, each containing its own sounds, and each time I load a sound I generate a new source and attach the sound buffer to it. The first few sources are generated fine, but after I have generated a few, it stops generating them, and I get errors.
Is there a limit to the number of sources that I can create or something?
Thanks for any help.
- Weasalmongler
What error(s) do you get back from alGetError? This doesn''t sound normal. I''m digging through the OpenAL source code looking for a cause, but it''s difficult without knowing exactly what error message I''m looking for.
Author
alGenSources(1, &temp->source)
returns : "Invalid Value" as a "alGetError()" message.
- Weasalmongler
[EDIT : Then I get an "Invalid Name" error when binding the buffer to the source, but that is obviously because alGenSources fails and "temp->source" is invalid]
[edited by - weasalmongler on July 3, 2002 5:14:57 AM]
returns : "Invalid Value" as a "alGetError()" message.
- Weasalmongler
[EDIT : Then I get an "Invalid Name" error when binding the buffer to the source, but that is obviously because alGenSources fails and "temp->source" is invalid]
[edited by - weasalmongler on July 3, 2002 5:14:57 AM]
Well, I wasn''t finding any potential issues in the source code, then I figured you''re probably using Windows, so I should look in the Windows OpenAL source code 
. Here''s what I found:
AL_INVALID_VALUE can be flagged:
If you request more than are available through whatever internal device OpenAL is using (this check isn''t needed in the Linux code, so I didn''t see it). This is probably your problem.
If there''s an internal out of memory error (I''m not sure why they''d do INVALID_VALUE for this?).
I didn''t know there was a maximum number of sources until I looked into this
. Here''s what I''ve found out: The maximum number of sources is apparently limited to 32 in Windows (only) because of some limit with DirectX 8. Look in openal/win/Alc/ALc.c to get a better understanding of this (search for "MaxNoOfSources", you''ll see what I mean). I may have to contact the developers in inquery about this issue, actually...
. Here''s what I found:AL_INVALID_VALUE can be flagged:
I didn''t know there was a maximum number of sources until I looked into this
. Here''s what I''ve found out: The maximum number of sources is apparently limited to 32 in Windows (only) because of some limit with DirectX 8. Look in openal/win/Alc/ALc.c to get a better understanding of this (search for "MaxNoOfSources", you''ll see what I mean). I may have to contact the developers in inquery about this issue, actually...
Actually weasalmongler, i have exactly the same problem as you do.., but i generate about 15/20 sounds.
I tought the problem was mine, but now i see the problem is OpenAL itselft.,
Null And Void, if a card as for example 8 hardware channels, does this means we will only be able to generate 8 sources ?
Isn''t OpenAL able to use Software mode when there''s no more hardware channels available ?
Thanks,
Bruno
I tought the problem was mine, but now i see the problem is OpenAL itselft.,
Null And Void, if a card as for example 8 hardware channels, does this means we will only be able to generate 8 sources ?
Isn''t OpenAL able to use Software mode when there''s no more hardware channels available ?
Thanks,
Bruno
Author
Oh well, unless anyone knows a way around this then I''ll look into FMOD.
Anyone know a way around it that they are willing to share?
- Weasalmongler
Anyone know a way around it that they are willing to share?
- Weasalmongler
Actually, you will have the same problem with FMOD 
After some samples, he won''t load them anymore.
I''m not sure how to handle this....,
Anyone has any ideias ?
Bruno
After some samples, he won''t load them anymore.
I''m not sure how to handle this....,
Anyone has any ideias ?
Bruno
Bruno, look at the source code that I referenced above if you want the ''whole story''. Basically, this is what it does:
If you select DirectSound3D for the device:
If you select DirectSound, you automatically get 32 sources.
If you select WaveOut, you automatically get 32 sources.
I think this is a serious annoyance, and today I''ll try to look into the reasoning behind this further (mainly because the ports of OpenAL don''t have this issue, as far as I can tell).
- If DirectSound3D supports more than 31 sources, OpenAL assumes it''s lying and clamps it to 31.
- If DirectSound3D supports less than or equal to 15 sources, OpenAL falls back on software mode, but allows you to use 16 devices.
I think this is a serious annoyance, and today I''ll try to look into the reasoning behind this further (mainly because the ports of OpenAL don''t have this issue, as far as I can tell).
Hey NULL, do you have something to do with the ports to windows ? This problem is non-existent in Linux ?
Are you on the OpenAL team ?
Are you on the OpenAL team ?
quote:Original post by Bruno
Hey NULL, do you have something to do with the ports to windows?
Nope.
quote:Original post by Bruno
This problem is non-existent in Linux ?
There is no check in the allocation of sources in Linux, but I haven''t actually ''stress tested'' the implementation. So, as far as I know, this problem is non-existent in Linux. I''m working on getting the official state of this issue (i.e. no plans to fix it, what OS''s it affects, et cetera).
quote:Original post by Bruno
Are you on the OpenAL team?
Nope.
This topic is closed to new replies.
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