Summary
When using the Chaos Break Event to handle fractures in a GeometryCollection, the Extents vector returned in the event may not correspond to the expected axis alignment. For example, the X and Y components can be swapped or misaligned.
After some experiments, I found that this issue is caused by the initial rotation of the mesh that is set before it is fractured in Unreal Engine.
Please select what you are reporting on:
Creative
What Type of Bug are you experiencing?
Other
Steps to Reproduce
Create box => scale along X => rotate for 90 degree around Z => fracture, like simple slice => make blueprint with this geometry collection => On Chaos Break Event => Print(String) = Extents (From Break Event Structure)
Expected Result
When retrieving the Extents of a breaking fragment, the user expects the vector to be aligned in either global or local space.
Observed Result
The Extents vector contains a baked-in rotation offset originating from the initial rotation of the mesh, which results in incorrect values.
Platform(s)
UE 5.4
