How do I make a low-poly mesh collider for a model


I have a model of a truck:!74569&authkey=!AEzVSPgd5bJ4BcA&ithint=file%2Cblend

It has a “body” component.
This component has > 1500 verts, > 2000 faces/tris, ~ 4000 edges.
I want to make a concave mesh collider for my truck body so that I can do stuff when my truck rolls over or hits things.
I’m using the truck in a game in Unity, and this requires that the mesh for my collider has a “poly count” of < 255.

I’ve googled around and it looks like I can do stuff like deicmate it, and I’ve found I can manually dissolve vertices and things, and so far I’ve about halved the various counts, but it is taking forever and I don’t really want to have to do the same thing for the next truck.

Is there some way of automating this process?
I want a mesh that is a good approximation of the shape of the truck body, but it’s fine for it to be far less detailed.

I’m a programmer, not a 3d artist, so forgive me if this question is silly:)

Ok, I went ahead and built a simple collider that exceeds the polycount limit of Unity. But I’m sure you’ll be able to reduce the polycount to your needs and liking while still maintaining the basic shape. Her you go .blend, enjoy.

Ohh, before I go. I have to tell you that the collider mesh it self has a couple of modifiers that will help you to adjust it’s volume as well ass give you an insight on how will the mesh look like once it’s triangulated when exported.

The mesh collider is on the second layer while the original model is on the first.

Nice, thanks, I’ll give it a go when I get some time:)