(This function is part of SDL_mixer, a separate library from SDL.)

MIX_SetGroupPostMixCallback

Set a callback that fires when a mixer group has completed mixing.

Header File

Syntax

bool MIX_SetGroupPostMixCallback(MIX_Group *group, MIX_GroupMixCallback cb, void *userdata);

Function Parameters

MIX_Group *	group	the mixing group to assign this callback to.
MIX_GroupMixCallback	cb	the function to call when the group mixes. May be NULL.
void *	userdata	an opaque pointer provided to the callback for its own personal use.

Return Value

(bool) Returns true on success or false on failure; call SDL_GetError() for more information.

Remarks

After all playing tracks in a mixer group have pulled in more data from their inputs, transformed it, and mixed together into a single buffer, a callback can be fired. This lets an app view the data at the last moment that it is still a part of this group. It can also change the data in any way it pleases during this callback, and the mixer will continue as if this data came directly from the group's mix buffer.

Each group has its own unique callback. Tracks that aren't in an explicit MIX_Group are mixed in an internal grouping that is not available to the app.

Passing a NULL callback here is legal; it disables this group's callback.

Version

This function is available since SDL_mixer 3.0.0.