Tried everything but Unreal collision does not work

(Solved - if anyone is looking at this in the future, the current rules for defunct collisions are:
-Use the correct naming convention: UCX_[meshname]_##
-Separate your collisive meshes as necessary.
-Ensure each of your collisive meshes is 3d, no matter how small or big: id est the closest to a true planar collision is a plane extruded by a microscopic amount. )

I have been trying to import my FBX from Blender to UE4, but sadly it has been to no avail. No matter whether “one UCX per hull”, the collisions still don’t work. This is probably my own mistake; but I just cannot see where I am going wrong. I have aleft a link to download my FBX if anyone could check it out. Any help would be much appreciated :3

The model: a stairway

The download link for the stairs:

Open the mesh in the editor. Turn on view collisions to make sure you have collisions on your meshes.

For some strange reason the collisions I built are not showing up at all; which is strange because I have around 13 UCXs in the FBX file, but they have not been showing up in the UE4 editor. Would somebody be able to open my FBX file and show me what has gone wrong? For now I’ll try exporting it in the old ASCII style of FBX.


Also, here is a picture of my naming convention: UCX_[name]_## . This seems to be the problem for many users, but changing it hasn’t helped me.

I replied to your email, but I will also post here for anyone who runs into a similar issue.

The issue appears to be that each UCX collision hull is just a flat plane, rather than an actual 3D shape. Collision hulls require depth to be generated. So rather than looking like this

Each hull must look like this

When you edit the mesh you could just add a box collision for each step.

Thanks so much, Shirk :smiley: I have been stuck with this for ages. It worked almost instantly. I’ve been trying to design my meshes and collisions with the minimal possible collision space; and wanted to use planar collisions, though now it has become clear to me that every collision space must be 3d. Thus, I have taken your advice and a step further - extruding the collisive meshes by 0.2mm in the inacessible spaces (behind and under the stairs, as well as to the outward directions of the supporting triangles. Perfect. :wink: