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IDirectMusicSynth::SetNumChannelGroups method (dmusics.h)

The SetNumChannelGroups method instructs the synthesizer to set its number of channel groups to a new value.

Syntax

HRESULT SetNumChannelGroups(
  DWORD dwGroups
);

Parameters

dwGroups

Specifies the number of channel groups requested.

Return value

SetNumChannelGroups returns S_OK if the call was successful. Otherwise, the method returns an appropriate error code. The following table shows some of the possible return status codes.

Return code Description
DMUS_E_SYNTHNOTCONFIGURED
Indicates that the synth is not open or not properly configured.
E_FAIL
Indicates that the method is unable to allocate the channel groups.

Remarks

Even though IDirectMusicSynth::Open tells the DirectMusic "port" how many channel groups to create, the application might later need to dynamically increase or reduce that number with a call to SetNumChannelGroups.

Each channel group supports a set of 16 MIDI channels. For example, if dwChannelGroups is set to three, the synthesizer creates 48 channels.

For more information, see the description of the IDirectMusic interface in the Microsoft Windows SDK documentation.

Requirements

Requirement Value
Target Platform Desktop
Header dmusics.h (include Dmusics.h)

See also

IDirectMusicSynth::Open