Collision is necessary for an object to have the most absic interaction in the world.
Collision meshes are standard *.mdl files with materials and UV coordinates removed.


Import an *.x or *.obj file into the Material editor. There's no need to set diffuse, normal and special maps or adjust any parameters, since collision meshes aren't visible in-game.


Now comes the slightly different part: saving. First save the collision mesh as a standard model

  1. Save the collision mesh as you would any other standard uncompressed mesh. The button can be found on the top toolbar
  2. Press F3.
  3. Immediately after loading a model, you will be prompted to set where to save the compressed collision model. The suggested action here is to overwrite the existing *.mdl
That's it! Your single collision mesh is saved and ready to be used in the game. Do the same for all collision meshes for the object you're importing.

Collision models DO NOT need textures or materials! You can leave the default textures/materials on the collision mesh as they are NOT used!


Collision meshes are implemented through the *.asb files. At the bottom of the *.asb file two sections can be found.

  • CollisionMesh:{ } - Standard collision mesh used for detecting weapon hits
  • ConvexCollisionMeshes:{ } - Convex collision meshes used for detecting if one object is "bumping" into another

ConvexCollisionMeshes MUST be convex models. Non-convex models WILL NOT WORK!

You can have as many convex collision models as you want.

Position of collision meshes CANNOT be changed! Export them already placed around/on the object with the pivot set at 0!