IDirectMusicSynth::SetChannelPriority method (dmusics.h)

The SetChannelPriority method sets the priority of a MIDI channel.

Syntax

HRESULT SetChannelPriority(
  DWORD dwChannelGroup,
  DWORD dwChannel,
  DWORD dwPriority
);

Parameters

dwChannelGroup

Specifies the group the channel is in. This value must be one or greater.

dwChannel

Specifies a channel in the channel group. This parameter is an index in the range 0 to 15.

dwPriority

Specifies the priority ranking of the channel. For a list of the ranking values that are defined for this parameter, see the IDirectMusicPort::GetChannelPriority reference page in the Microsoft Windows SDK documentation.

Return value

SetChannelPriority returns S_OK if the call was successful. Otherwise, the method returns an appropriate error code.

Remarks

The SetChannelPriority method is implemented to support the MIDI synthesis engine. This method allows the allocated voices to run at different priorities, depending on which channel they are on. Sometimes voices are freed when there are too many to deal with at one time, and they are kicked out based on the priority of the channel they are on. If a voice comes in on a higher-priority channel, and if there are no more free voices, the MIDI synthesis engine will steal a channel from the lowest-priority voice and reassign the channels.

For more information, see the description of the IDirectMusicPort::GetChannelPriority and IDirectMusicPort::SetChannelPriority methods in the Windows SDK documentation.

Requirements

See also

IDirectMusicSynth::GetChannelPriority