How can I make a CollisionShape3D and MeshInstance3D hollow?

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:bust_in_silhouette: Asked By Klank

I know of this method, where, to create a cubic room, instead of placing six squares as walls, you can place a single cube and then make it hollow. Is this possible in Godot? If so, how?

:bust_in_silhouette: Reply From: Floux

I think you can try CSGCombiner with CSGShape.

https://docs.godotengine.org/uk/stable/classes/class_csgcombiner.html