al_attach_mixer_to_mixer
bool al_attach_mixer_to_mixer(ALLEGRO_MIXER *stream, ALLEGRO_MIXER *mixer)
Attaches a mixer onto another mixer. The same rules as with al_attach_sample_instance_to_mixer apply, with the added caveat that both mixers must be the same frequency. Returns true on success, false on error.
Currently both mixers must have the same audio depth, otherwise the function fails.
See also: al_detach_mixer.
Examples: ex_mixer_chain
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