Collision Mesh naming convention

I have a suffix “low” on my static meshes. Does the collision mesh need to have this suffix? Other than the prefixes: "UCX " and “SM”, all the names are identical.

Your LODs should also be named identical to the mesh, so adding a suffix to a mesh within a set of meshes of the same item makes little sense…

If your meshes are just called low_1mwall instead of 1mwall to differentiate a half wall (or anything similar).

First, may I suggest changing low to a height value? 1mx1m_wall vs 2mx2m_wall is probably a lot easier to understand for whomever comes next to the project.


Yes, the low needs to be within the collision hull for it to import correctly.
And if there’s any
(Within an empty group of the same name if in blender)

Another note. The engine tends to ignore/discard collision boxes that touch each other… kinda hate that since it makes it near impossible to section off an item easily / you need to move some vertices or shrink/enlarge the hull…

Thank you for responding. I use the suffixes “low” and “high” with meshes because I texture in Substance Painter and this differentiates a high resolution mesh from a low resolution mesh which it requires to create the normal map.

I appreciate the extra tips about collision meshes. How sensitive is Unreal to the collision mesh? For instance, can some of the static mesh extend beyond the collision mesh, or must all polys be within the collision mesh? For instance a stairwell with a wedge shaped collision mesh where the edge of the steps goes beyond the face of the collision mesh?

Thank you again for your help.

They are completely uncoupled when you make your own and import via FBX.

You could have the mesh of a cube with the collision of a star or vice-versa no problem.

Just remember that a collision box is cheaper than a convex hull of the same vertex count, so try and use as many “engine native” forms as possible.
They don’t change much at all unless you port to very low memory stuff like mobile. And now a days even that runs fine without such considerations really…

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