Geometry Collection loses collision after breaking/fracturing. [Chaos Destruction]

Eight_P
Thu, 11 Dec 2025 15:44:01 +0000
World Creation

I have been recently looking into Chaos destruction with 5.7 and encountered numerous scenarios of Geometry Collections losing their collision (at runtime) in unexpected (and hopefully unintended) ways.

The issue seems to occur when the first breaking/fracturing damage to an intact GC is not causing any further internal damage (or so).
Probably better explained by these examples:

A GC with level 2 bones breaking into the level 1 clusters but not breaking the level 2 connections due to disabled “damage from collision”:

It can also be replicated with a two-level GC set to static/kinematic on the actor object type.

However, it seems to only happen on the “first hit” to the GC.

Which can also be shown when setting some of the bones in a cluster to static/kinematic.

This is all done using Apply External Strain + Apply Breaking Linear Velocity (radius: 1, propagation depth: 0), but I also found the same behavior using the default FS_MasterField.

I’m just hoping for someone smart to see this and shed some light on it.
Thank you.

9 posts - 5 participants