Description

While investigating an issue with Cull Distance Volumes, I noticed that AVolume::EncompassesPoint has a broken default implementation when WITH_PHYSX is not defined. If only chaos is enabled it will fallback to using the brush's bounds instead of exact geometry, which will be very inaccurate for weirdly shaped volumes. I believe the GetSquaredDistanceToCollision function it calls works fine in Chaos and this is just a remnant of when PhysX was the only option. There also may be other places in Engine that need to be checked for out of date WITH_PHYSX calls

This would cause very different behavior between PhysX and Chaos for any systems like Post Process Volumes or Cull Distance Volumes that need to see if a point is inside a volume

Steps to Reproduce

Effects depend on the exact shape of the volume, comments have linked bug referencing behavior

Have Comments or More Details?

There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-101956 in the post.

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Won't Fix
ComponentUE - Simulation - Physics
Affects Versions4.265.0-m1
CreatedOct 26, 2020
ResolvedJul 19, 2022
UpdatedJul 19, 2022
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