>> I have a question inspired by qartar's problem with streaming to the
>> buffers. I was wondering what kind of performance benefits might result
>> from streaming blocks of data rather than uploading the entire sound file.
>> In what cases might such a solution have great benefit and in what
>> situations might it just be useless?
> Streaming is mostly helpful for when the sound is large (at least a few
>
megabytes uncompressed), since it doesn't have to hold the whole uncompressed
>
file in memory, or read/decompress the whole file at once before playback can
>
start. Hardware devices can have memory restrictions, too.
>
Some implementations may also have restrictions that can cause integer
>
overflows.. eg. if the current position of a sound is tracked using a 22.10
>
fixed-point integer, that only leaves 22 bits to represent the whole-sample
>
position. 22 bits can hold a value up to 4,194,304, so a buffer that has more
>
than a couple million samples may risk having the position value overflow and
>
wrap around back to 0 before it can finish.. or the end point itself can wrap
>
around, so only part of the beginning is played before stopping.
>
Shorter sounds won't really benefit from streaming though, and may actually be
>
a detriment, if the overhead of buffer queues and such are more costly than
>
simply loading it all at once. Streaming is also detrimental because the
>
buffers can't be as easily reused and shared among multiple sources.
>
IMO, most regular sound effects would be better not streamed, so they can be
>
cached in an OpenAL buffer for quick reuse. Music and long dialog may be
>
better streamed, since they're going to be larger and more unique (they won't
>
be reused as often for caching to be any real benefit).
Thanks :D, just the kind of answer I was looking for.
-Mikfig
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