本文內容
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.hLibrary: Dmime.dll, Dmimed.dll
See Also
© 2004 Microsoft Corporation. All rights reserved.