| Microsoft DirectX 9.0 SDK Update (Summer 2004) |
Performance Channels
Every playing sound consists of one or more parts. A part might be a MIDI channel, a part in a DirectMusic Producer segment, or a waveform. Often a part corresponds to a single musical instrument.
A performance channel controls the route taken by a part through an audiopath. It maps the part to a resource on the synthesizer (an instrument timbre or a waveform) and also enables the output of the synthesizer for the part to be sent through a particular configuration of buffers for the application of effects. Every message that contains information about a part also specifies the part's performance channel, so that it can be routed correctly. Every performance channel has its own settings for pan, volume, and transposition.
Performance channels are similar to MIDI channels, but whereas traditional MIDI playback is limited to 16 channels, the number of performance channels is virtually unlimited.
Note The array of performance channels in the DirectMusic API is zero-based, but in DirectMusic Producer it is one-based. Performance channel 1 in DirectMusic Producer is performance channel 0 in the API.
See Also
© 2004 Microsoft Corporation. All rights reserved.