Miles Sound System SDK 7.2a

AIL_set_sequence_tempo

The function AIL_set_sequence_tempo specifies an increase or decrease in the normal playback tempo of a sequence.

void AIL_set_sequence_tempo(
  HSEQUENCE S,
  S32 tempo,
  S32 milliseconds
);

In Parameters

S: indicates the sequence whose tempo is to be altered.
tempo: specifies the new tempo percentage.
milliseconds: specifies a delay time over which the requested tempo change should take place.

Discussion

Tempo values are expressed as a percentage relative to the normal (unscaled) tempo values specified in a sequence's MIDI Set Tempo (type 51H) meta-events. The normal relative tempo for a sequence will be 100, or 100%.

The milliseconds parameter allows the application to specify a number of milliseconds from 0 (immediate) to 2.1 billion (slightly more than three weeks) over which the relative tempo should ramp up or down to reach the specified value. This graduation time is measured only while the sequence is actually playing; if a sequence is paused during a ramp-up or ramp-down with a call to AIL_stop_sequence, the graduation effect itself will continue, along with the rest of the sequence's performance, upon a subsequent call to AIL_resume_sequence.

Group: XMIDI Services
Related Functions: AIL_quick_set_speed, AIL_resume_sequence, AIL_sequence_tempo, AIL_stop_sequence
Related Basic Types: HSEQUENCE, S32, void