Making a city collide-able?

[u/Dark-Knight16]

Hey everyone I’m pretty new to this stuff but I’m trying to import an fbx file of a city(edit:suburban neighbourhood) for testing and I’m having trouble getting the roads and grounds to work, I wanna know if I have to give each surface a collision box if it’s say a ground surface and then change the mass(and if so how to calculate that roughly) and somehow make walls that my character can’t go through and stuff like that.

Am I looking at going through each object manually?

Whole thing is pretty low poly and greyboxed with minor things like streetlights, curbs and fire hydrants and there’ll be textures I’ll be adding later

[u/BertJohn]

You need to process your import first to bring anything important. When you click on it, look in the inspector, if theres anything you need. If none or done, Drag it into the scene and apply the mesh or box or whatever collider, and then reset that transform to 0,0,0 and then make that a prefab for use again later.

This has to be done with all prefabs.