How to remove a section of a CubeGeometry?

Question

At the moment I'm using ThreeCSG/CSG to subtract a small cube from a much larger cube. This works fine, but only the look of it changes not the actual geometry. So when using PhysiJS (Physics engine) on another cube, it doesn't fall into the hole but acts like it normally would. Click for Demo.

Is there any way I can actually remove a section from a CubeGeometry so that objects can fall into it - not just for display purposes? Thanks!

Answer 1

ThreeCSG does change the geometry, by which I mean geometry in the sense of Three.js -- the collection of vertices, the faces, etc. I think what you mean is that ThreeCSG does not change the physics-based properties of your object.

According to https://github.com/chandlerprall/Physijs/wiki/Basic-Shapes , it appears as though you have to use Physijs.ConcaveMesh as it "matches any concave geometry you have, i.e. arbitrary mesh", and it is the only one that has a change of supporting a non-convex physical object.