Sound and Channel setMode function

FMOD Engine
1

Hi, I have a question about the setMode function.

Does setMode for channels and sound internally |= the mode?
I.e. if I create a sound with FMOD_3D and then call setMode on the sound with FMOD_LOOP_NORMAL, would that then overwrite the FMOD_3D bits?

I would have expected that it does, so I found myself using a pattern similar to this:

// Must ensure that the channel is set up for 3D playback
FMOD_MODE mode;
ERRCHECK(channel->getMode(&mode));
if ((mode & FMOD_3D) == 0)
{
    mode &= ~FMOD_2D;
    mode |= FMOD_3D;
    ERRCHECK(channel->setMode(mode));
}

This ensure that the previous bits are still set, but 2D has been changed to 3D if it wasn’t already.

Then I encountered this code in the 3D core example (Line 46 of 3d.cpp), and I got a bit confused:

result = system->createSound(Common_MediaPath("drumloop.wav"), FMOD_3D, 0, &sound1);
ERRCHECK(result);
result = sound1->set3DMinMaxDistance(0.5f * DISTANCEFACTOR, 5000.0f * DISTANCEFACTOR);
ERRCHECK(result);
result = sound1->setMode(FMOD_LOOP_NORMAL);
ERRCHECK(result);

This seems to imply that setMode doesn’t overwrite the existing mode?

Would appreciate some clarity, thank you:)

2

There is a little more processing depending on what kind of object setMode is being called on and what mode is being set, but generally speaking yes, |= is used internally when setting FMOD_MODE flags.

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