---- How to write your own audio driver for it2play ----

1) Include the header "../../it_music.h"

2) Implement the following functions using your audio API of choice:

  void lockMixer(void); // waits for the current mixing block to finish and disables further mixing
  void unlockMixer(void); // enables mixing again
  bool openMixer(int32_t mixingFrequency, int32_t mixingBufferSize); // 16000..64000, 256..8192 (true if ok, false if fail)
  void closeMixer(void);

3) When the audio API is requesting samples, make a call to Music_FillAudioBuffer(), f.ex.:

   Music_FillAudioBuffer((int16_t *)stream, len / 4);
  
4) Make your own preprocessor define (f.ex. AUDIODRIVER_ALSA) and pass it to the compiler during compilation
   (also remember to add the correct driver .c file to the compilation script)

5) In "it_music.h", insert your preprocessor define and include in the "AUDIO DRIVERS" #ifdef chain and
   include your audio driver header in there.

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You can look at audiodrivers/sdl/sdldriver.c if you need some references...
