Hit box of custom 3D objects?

The "World3DModel" class will get a new method to set a collision shape (the collision shape prevents the player from walking "through" the object, and is also relevant for physical objects) for the model. This can either be a primitive box or sphere shape (limited, but very fast in terms of performance, and in most cases definitely sufficient), or a mesh accurate collision shape (i.e. the object geometry will be used as collision shape).
However, the actual hit box (detection when hitting it with a pickaxe, for example) will always be mesh accurate (i.e. the object geometry).