[Openal] Synchronising two sample streams

[Daniel PEACOCK]

Hi,

A simple solution might be to play both streams (on two different Sources)
all the time.   One Source will be silent (gain = 0) and the other audible
(gain = 1).  When you need to switch between the streams, simply raise the
gain on one Source, and lower it on the other.

You can use the alSourcePlayv (vector version of alSourcePlay) function to
start the playback of the two Sources at the same time.

Dan

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             Marian Schedenig                                              
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Hi!

I'm thinking about implementing the following concept, but I'm not sure how

i'd go about doing that with OpenAL:

I want to play a music stream through one source and two (or more buffers).

Then, at some point, I want to switch to a somewhat different music stream
by
starting it *at the exact (!) same point* (offset from beginning) currently

being played by the first stream and smoothly fading to the new stream.

My first idea was to simply start the second stream on a separate source
with
a separate set of buffers and then fade over. But how do I know *when* to
start playback of the second source? Assuming I've found the correct offset

in the second stream which I have already *buffered* for the first stream -

how to I know when OpenAL is actually about to start playing that latest
buffer on the first source, so I can sync up the second source accordingly?

I guess if I can't get the required "trigger" from OpenAL, I'll have to mix
my
buffers manually in software and play the result through a single source -
but that's something I'd really like to avoid.

Thanks for any hints,
Marian.

--
http://www.musgit.com | http://marian.musgit.com

Hofstadter's law: "It always takes longer than you think,
even when you take account of Hofstadter's law".
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