Hi,
I’m testing the Occlusion system in FMOD for Unreal and I would like to confirm whether the current behavior is correct or if I’m missing something in the setup.
I followed the official documentation:
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Created a continuous parameter in FMOD (0–1) named exactly as the “Occlusion Parameter” in the plugin settings.
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Automated a low-pass filter in FMOD so that the parameter value controls frequency cutoff (0 = 20 kHz, 1 = 20 Hz).
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Enabled Occlusion on the FMOD Audio Component in Unreal (Occlusion Trace Channel set to Visibility, tested also with complex collision).
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The parameter is local (instance parameter).
The issue:
When moving the listener around a test map, the occlusion parameter only receives values 0 or 1.
There are no intermediate values such as 0.2, 0.5, 0.7 etc.
Even when the sound source is only partially obscured by geometry, the value jumps straight from 0 to 1.
I’ve tested multiple collision settings and trace channels, but the behavior is always binary.
My question:
Is this the intended design of FMOD for Unreal occlusion (single line trace → 0 or 1)?
Or should the FMOD integration provide continuous occlusion values by default?
I want to confirm whether the plugin is working correctly, or if continuous occlusion requires implementing a custom solution (e.g., multiple raycasts and setting the parameter manually).
Using FMOD Studio 2.03.10 and UE 5.4 Thanks in advance for clarification!