Collision not working

I have a blueprint with two objects in it like so: a foundation piece and an air storage tank on top of it.

air_storage_collision.png

The screenshot above shows the lines that are rendered for the foundation piece when you show collision in the editor (“Show” button and select “Collision” from the menu).

Right now, we’re seeing that hit-testing (via GetHitResultAtScreenPosition()) doesn’t work with the foundation specifically because it has collision geometry, and this seems to prevent it from working.

The hit testing passes right through the foundation piece regardless of whether we pass in true or false for “bTraceComplex” and regardless of which version of GetHitResultAtScreenPosition() we call or what combination of ECollisionChannel or ETraceTypeQuery flags we use.

The collision for this piece is in UCX_rendermeshname_## format per unreal documentation.

A similar foundation piece with identical geometry does work because it uses the render mesh for collision instead.

Why might this not be working? If the Unreal editor can render it as in the screenshot above, it clearly knows that it exists; why is it not colliding properly?

I’ve now put the .uasset for the static mesh for the foundation piece up in the FTP site; it’s in

ftp://Rocket_FTP_Dropbox@ftp.epicgames.com/Mothership_Entertainment/CollisionBug/city-foundation-1x1-01.uasset

OK, this is fixed now – what we actually needed to do was go into the static mesh editor and go to Static Mesh / Body Setup / Collision Complexity and set Use Simple Collision as Complex.

That’s an interesting issue!

I’ve verified that UBX_RenderMeshName works for pawn collision with a tree trunk I set up in 3ds max

Have you tried UBX? B is for box, (UCX is for misc. convex shapes)

You might need to update your FBX Plugin and re-export.