How do you generate a collision box to fit the mesh on an imported model

Hello, I’ve imported a model from blender, a gltf, its a big city map, so quite a complex model, is there a way I can generate a collision box on the mesh so that the charater doesn’t fall through the floor or walk through objects, I tried to open it up in the mesh editor and you can generate a box collision preset and some other stuff but I would have to create a lot of them and adjust them to each part of the map, is there a quicker way to do it where it calculates a collision box around the mesh, or else I would have to manually place invisible walls around each part of the map

By default the engine should generate collision on every static mesh that is imported.
If it is not the case you should look at the collisions import options and make sure the “Import Collisions” is ticked and Fallback is anything but None:

If you want Box instead of the 18DOP you can just change the Fallback Collision type.

If it’s a whole map that you are trying to generate collision on, I would recommend breaking it up into smaller parts for better results. Generally city maps are made with many modular pieces and individual building models instead of as one large mesh.

You can try to generate collision on the whole thing or on individual parts with the Convex Decomposition tool. In the Static Mesh viewer, open the window for it if it’s not already.

The Hull Count is the maximum number of collision primitives it will generate. The Max Hull Verts are the number of vertices each collision mesh can have. And the Hull precision is how closely it will follow the geometry of your model. Usually I turn this up between 950000 and 1000000.

Okay thanks, yeah its in modular parts so I can work on one city block at a time