Type Alias


A block called when an audio unit renders audio.



This block is called by the base class’s AURenderBlock block before and after each render cycle. The observer can distinguish between before and after using the unitRenderAction_PreRender and unitRenderAction_PostRender action flag values.

The block takes the following parameters:


The pointer to the action flags.


The HAL time at which the input data will be rendered. If there is a sample rate conversion or time compression/expansion downstream, the sample time will not have a defined correlation with the AudioDevice sample time.


The number of sample frames to render.


The index of the output bus to render.

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