From:	Jose Manuel Lopez-Cepero <sigma AT ctv DOT es>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Allegro sound bug?
Date:	Thu, 20 Mar 1997 22:42:55 +0100
Organization:	Unisource Espana NEWS SERVER
Lines:	41
Message-ID:	<3331AF5F.2871@ctv.es>
References:	<5gh3c8$nhi$1 AT news DOT sas DOT ab DOT ca>
Reply-To:	sigma AT ctv DOT es
NNTP-Posting-Host:	macarena.ctv.es
Mime-Version:	1.0
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Hya there!

kalyniuk AT freenet DOT edmonton DOT ab DOT ca wrote:
 
> I've found a weird problem using Allegro's play_sample() function. If I
> use it anywhere in my program other than within a while loop the sample
> sounds crappy (scratchy and half the volume). For example:
> 
>         while(!keypressed())
>                 if(mouse_b & 1)
>                 {
>                 play_sample(the_sample, 100, 128, 1000, FALSE)
>                 }
>         // this works fine
Well, think about what it does. If you hold the button for a small
while, then you are sending a lot of play_sample()'s statements. Since
Allegro has a builtin limit on the number of voices that can be active
at any time (8, at least for SBPro), this means that in 8 loops of the
while{} statement (very very small time) you flood the mixer with 8
copies of the same sample. Of course it sounds glorious, try doing the
same thing on an 8 channel tracker and you'll _hear_ the difference :-)

 
>         if(move_guy > 300)
>                 {
>                 play_sample(the_sample, 100, 128, 1000, FALSE)
>                 }
>         // this does not

Well, this only places a copy of the sample on the mixer. Guess what
happens :-)

As a solution you may want to try this: a) increment the mixing rate and
b) duplicate the line (ie. play the sample twice) if it doesn't work.

Hope it helps 8-)

-- 
 _*                        
\ |/_|\/||\                                 sigma AT ctv DOT es      
_\|\/|  ||_\  (formerly Sigmatech)      Jerez / Cadiz / Spain

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