Problem loading a preset for an AUV3 plugin on iOS

MacOSX and iOS
#1

Hi, it seems that calling setProgram(int) to load a plugin’s preset from a host app doesn’t work on iOS.

The current code builds the AUPreset struct populating only the preset number, using an empty string for the name.

void setCurrentProgram (int newIndex) override
{
    AUPreset current;
    current.presetNumber = newIndex;
    current.presetName = CFSTR("");

    AudioUnitSetProperty (audioUnit, kAudioUnitProperty_PresentPreset,
                          kAudioUnitScope_Global, 0, &current, sizeof (AUPreset));

    sendAllParametersChangedEvents();
}

Populating correctly also the corresponding preset name works fine, for example:

void setCurrentProgram (int newIndex) override
{
    AUPreset current;
    current.presetNumber = newIndex;
    
    CFArrayRef presets;
    UInt32 sz = sizeof (CFArrayRef);

    if (AudioUnitGetProperty (audioUnit, kAudioUnitProperty_FactoryPresets,
                              kAudioUnitScope_Global, 0, &presets, &sz) == noErr)
    {
        if (const AUPreset* p = (const AUPreset*) CFArrayGetValueAtIndex (presets, newIndex))
        {
            current.presetName = p->presetName;
        }
        CFRelease(presets);
    }

    
    AudioUnitSetProperty (audioUnit, kAudioUnitProperty_PresentPreset,
                          kAudioUnitScope_Global, 0, &current, sizeof (AUPreset));
    
    sendAllParametersChangedEvents();
}
1 Like
#2

Thank you for reporting.