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Import level mesh/collision detection

Hey there,

I just started working with UE4, covered some very basics.
Now I want to port my stuff from an earlier project to UE4, in this case, a finished worldmesh. It’s a .3DS imported in Blender and exported as .fbx.
Only problem here: There’s no collision. Checking auto create collision just creates a collision hull around the mesh and any other option for collision generation is not accurate.

I just want to have accurate collisions to every plane, wall etc. so that you can actually walk on the ground without floating a bit above and walk through passages.
I’m actually not a 3D artist, so the worldmesh isn’t made by myself, but I got the basics working with Blender.

Thanks in advance.

You will either have to set up collision in your FBX file by editing it in Blender or equivalent: https://docs.unrealengine.com/latest/INT/Engine/Content/FBX/StaticMeshes/index.html#collision

Or within the scene add blocking volumes where you want collision to be: https://docs.unrealengine.com/latest/INT/Engine/Actors/Volumes/index.html#creatingvolumes

So there’s no way to, like, set every face of the mesh to be solid/have collision?
All I read about is creating boxes or something similar to put around the mesh to serve as collision box.
To be more precise, it’s a pretty old world mesh, containing a fort in the middle and a little village around it, additionally surrounded by some sort of palisade, which is just like a 2D plane or something.

Here’s a screenshot:
2f875d9e017502437d91d8e41541cf096092fb67.png

Okay, I got some other question.

Is there a difference between setting up collision in the FBX file, or placing blocking volumes concerning performance?

All you need to do to get accurate collision for something like this where every polygon has collision is to “Use Complex Collision as simple” for geometry
1975d4b8e6326dde78f00ac3b6bff528385f95b3.png

Well, that’s exactly what I needed, thanks a lot!

I know with Maya, all you have to do is Duplicate the mesh and rename it to UCX_YourMeshName.

I tried that before in Blender, but it didn’t really work for me. Maybe I did something wrong, dunno…

That doesn’t work as far as Im aware because a collision mesh cant have any concave faces (I might be wrong).

According to this page, you’re right. Just closed convex shapes.

Sorry for the double post, but I got a more general question concerning this, since it’s a pretty big mesh. I often read that using such meshes is inefficient and that you should should split things up and such.
So, what do you think now? Can I just this one big mesh to serve as levelmesh or should I split it up? And how exactly then? Wall by wall or entire buildings? And what about the materials? One material per mesh, I read. How can I update them in UE4?
Just added some UV maps to a material, but it didn’t applied on the mesh.

Sorry for this whole bunch of questions. Looking forward to hear from you!

Make the buildings a mesh, use the landscape tool for what the buildings will sit on. With the buildings, you can make them modular but you may run into lighting issues. I would just make any building that is connected or supposed to be standalone, a single mesh.

Okay thanks for the advice. And what about materials? Take a simple hut for instance. It would have three materials: floor, walls and roof. Is this a problem, as the mesh would use three different materials? 'Cause I often read about having just one material in a single mesh, which would not really work with whole buildings…
I’m just a bit confused right, dunno what’s better, what saves performance or whatever.