How to achieve terrain deformation with collisions?

Hi everyone !

I’m trying to achieve terrain deformation for my game. For the moment, I am using a Render Target to modify the material of the terrain at runtime (I’ve been following this tutorial Unreal Engine 4 Tutorial - Reactive Snow/Mud - YouTube ). It works pretty well but the problem is that the collisions aren’t modified, and I would like them to be.

I have no really idea on how to do this…