Primary and Secondary Segments

When multiple components are played simultaneously, either in the Microsoft DirectMusic Producer workspace or by applications, one is the primary segment and all others are secondary segments.

Note Although you can play segments, patterns, and other components in DirectMusic Producer, applications can play only segments. For simplicity, the remainder of this discussion refers to primary and secondary components as primary and secondary segments.

In DirectMusic Producer, you choose one component to be the primary segment by selecting it in the Transport List. You can also choose a component to be primary by making its editing window active. Any other component playing at the same time is a secondary segment and must be played by using the Secondary Segment Toolbar.

Choosing a segment as the primary segment is not a permanent setting, and you can choose a different segment in the Transport List at any time. When you transition from one segment to another by using the Transition Button, the new segment becomes the primary segment as soon as it begins playing.

Note Because only one segment at a time can be primary, playback of a primary segment that triggers another primary segment may be interrupted unexpectedly. See Preempted Primary Segments.

By default, certain tracks in the primary segment control behavior of secondary segments. For example, the groove track of the primary segment determines what patterns are available in secondary segments that are playing at the same time. For more information, see Controlling Segments.

Although it is possible to play secondary segments against silence, they generally start and stop while the primary segment is playing. Secondary segments are typically short, sometimes even less than a measure in length. By assigning a performance boundary to a segment in its Segment Properties window, you can coordinate its entrance as a secondary segment so it coordinates rhythmically and harmonically with the primary segment.

The behavior of primary and secondary segments is the same when a developer uses your files in a software application. The DirectMusic playback components are capable of playing any number of segments simultaneously, so a developer can combine multiple sound elements with as much layering as desired.

As you design a segment, keep in mind whether it will be used as a primary or a secondary segment when it is played by an application. For example, the primary segment might feature rhythm section parts, while the secondary segments contain instrumental solos that can be programmatically cued over the rhythm section.

Because a PChannel can only use one instrument sound at a given moment during playback, the bands in primary and secondary segments may conflict with each other. For more information, see Conflicts Between Bands.