A sample playback handle to be used by the engine.
- float** buf
- A pointer to the original buffer.
- int channels
- The number of channels.
- long buf_size
- The number of frames in the buffer.
- long offset
- The current offset in the buffer.
- float volume
- The volume to play the sample at (ratio from 0.0 to 2.0, where 1.0 is the normal volume).
- int start_offset
- Offset relative to the current processing cycle to start playing the sample.