Control Segments

A secondary segment can be designated a control segment, in which case it takes over the task of responding to certain calls such as DirectMusicPerformance8.GetCommand and controls some aspects of playback, such as the current tempo, chord, and groove level.

By default, the primary segment is the control segment. However, a secondary segment can be designated the control segment by passing the DMUS_SEGF_CONTROL flag to DirectMusicPerformance8.PlaySegmentEx. For more information, see CONST_DMUS_SEGF_FLAGS.

When a secondary segment is the control segment, the primary segment continues to function as a fallback source of control data. For example, if a secondary control segment does not contain a tempo track but the primary segment does, the tempo comes from the primary segment.