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The IDirectMusicPerformance8 interface is the overall manager of playback. It is used for adding and removing ports, mapping performance channels to ports, playing segments, dispatching messages and routing them through tools, requesting and receiving event notification, and setting and retrieving various parameters. It also has several methods for getting information about timing and for converting time and music values from one system to another.
If an application needs two complete sets of music playing at the same time, it can do so by creating more than one performance. Separate performances have separate tempos, whereas all segments within one performance must play at the same tempo.
IDirectMusicPerformance8 supersedes the IDirectMusicPerformance interface and adds new methods.
In addition to the methods inherited from IUnknown , the IDirectMusicPerformance8 interface exposes the following methods, arranged by category.
Audiopaths
Messages
Method
Description
AllocPMsg
Allocates memory for a performance message.
ClonePMsg
Makes a copy of a performance message.
FreePMsg
Frees memory allocated for a performance message.
SendPMsg
Sends a performance message.
MIDI conversion
Method
Description
MIDIToMusic
Converts a MIDI note value to a DirectMusic music value , using a supplied chord, subchord level, and play mode.
MusicToMIDI
Converts a DirectMusic music value to a MIDI note value.
Notifications
Parameters
Method
Description
GetGlobalParam
Retrieves global values from the performance.
GetParam
Retrieves data from a track.
GetParamEx
Retrieves data from a track, with support for self-controlling segments.
SetGlobalParam
Sets global values for the performance.
SetParam
Sets data on a track in the control segment.
Method
Description
AssignPChannel
Assigns a single performance channel to the performance and maps it to a port, group, and MIDI channel.
AssignPChannelBlock
Assigns a block of 16 performance channels to the performance and maps them to a port and a channel group.
PChannelInfo
Retrieves the port, group, and MIDI channel for a given performance channel.
Playback
Method
Description
GetSegmentState
Retrieves the currently playing primary segment state or the primary segment state that is playing at a given time.
IsPlaying
Ascertains whether a specified segment or segment state is currently being heard from the speakers.
PlaySegment
Begins playback of a segment.
PlaySegmentEx
Begins playback of a segment, with options for transition and audiopath.
Stop
Stops playback of a segment or segment state.
StopEx
Stops playback of a segment, segment state, or audiopath.
Ports
Method
Description
AddPort
Assigns a port to the performance.
RemovePort
Removes a port from the performance.
Timing
Method
Description
AdjustTime
Adjusts the internal performance time forward or backward.
GetBumperLength
Retrieves the interval between the time at which messages are placed in the port buffer and the time at which they begin to be processed by the port.
GetLatencyTime
Retrieves the latency time, which is the performance time being heard from the speakers plus the time required to queue and render messages.
GetPrepareTime
Retrieves the interval between the time when messages are sent by tracks and the time when the sound is heard.
GetQueueTime
Retrieves the earliest time in the queue at which messages can be flushed.
GetResolvedTime
Resolves a given time to a given boundary.
GetTime
Retrieves the current time of the performance.
MusicToReferenceTime
Converts a performance time in MUSIC_TIME format to performance time in REFERENCE_TIME format.
ReferenceToMusicTime
Converts a performance time in REFERENCE_TIME format to a performance time in MUSIC_TIME format.
RhythmToTime
Converts rhythm time to music time.
SetBumperLength
Sets the interval between the time at which messages are placed in the port buffer and the time at which they begin to be processed by the port.
SetPrepareTime
Sets the interval between the time when messages are sent by tracks and the time when the sound is heard.
TimeToRhythm
Converts music time to rhythm time.
Method
Description
GetGraph
Retrieves the toolgraph of a performance.
SetGraph
Replaces the performance's toolgraph.
Miscellaneous
Method
Description
CloseDown
Closes down the performance object.
DownloadInstrument
Downloads DLS instrument data to a port.
InitAudio
Initializes the performance and optionally sets up a default audiopath.
Invalidate
Flushes all queued messages from the supplied time forward and causes all tracks of all segments to resend their data from the given time forward.
Requirements
Header: Dmusici.h
Library: Dmime.dll, Dmimed.dll
See Also
© 2004 Microsoft Corporation. All rights reserved.