Convex Collision is incorrect for negatively scaled object that are attached to a physics actor. This doesn't happen for object with standard collision or object attached to non-physics actors. The console command "show collision" shows the collision as being correct but "pxvis collision" shows what is actually happening.

Licensee Description:

We have a feature in our game where users can mirror objects and re-parent them at will. This usually works fine but we've noticed that if the mirrored object is parented to an object that has physics enabled the collision will sometimes not get mirrored. This problem only seam to exist on objects that has convex collision. Using any other form of collision seam to work fine.

This is a feature that is very important to us and we are prepared to do some changes to the engine on our end if this turns out to be a bug.

Steps to Reproduce
  1. Open the attached test project
  2. PIE
  3. Look at the left block under Example 3

Results: The collision for the left block will not be negatively scaled to match the static mesh.

Expected: For the collision to match the object no matter what scale, attachment, and physics state.

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ComponentOLD - Anim
Affects Versions4.
Target Fix4.19
Fix Commit3726096
Main Commit3759284
Release Commit3813083
CreatedOct 26, 2017
ResolvedOct 30, 2017
UpdatedApr 27, 2018