Apple

AudioSampleType *out = (AudioSampleType *)ioData->mBuffers[0].mData;

...

etc.

On Jul 30, 2010, at 8:11 AM, Charlie Cullen wrote:

Hi,

I am having major(!) problems with render callbacks in a multichannel mixer application.

Basically, I intend to loop audio files of different lengths and so I had looked at the iPhone MixerEQGraph example and extended it to take in 8 audio files on 8 seperate busses.

The problem lies in setting up a functioning render callback for each bus of a different loop length.

Say I have 4 busses with 4 bar loops, 2 with 8 bar loops and another 2 with 16 bar loops. If I want them all to playback fully I think I need seperate render input functions for all 3 cases, to accommodate the different file lengths.

Curiously, I can get seperate render callbacks to function for each loop set if I create seperate SourceAudioBufferData structs for each loopset and then attach these to the mixer but the render input callbacks still do not work....

I have now tried implementing this in a number of different ways, but the best I can get it truncated loops of 4 bars for all busses!

I have looked at all the examples I can find, Apple WDC podcasts and trawled the API's- I know I'm missing something fairly fundamental :-)

Has anyone encountered this problem?

I would greatly appreciated any help or advice that anyone may have.

Thanks in advance,

Charlie

References:
	>multichannel mixer render callback problems (From: Charlie Cullen <email@hidden>)