I'm using Blender to create meshes I want to fracture in UE4. For this they need to be closed, otherwise their inner is not fractured correctly.
I'm creating a basic house from a cube. First I extruded the "door" inwards and made the vertices there so that it's closed. I exported it and it can be fractured correctly.
Now I tried to extrude two windows, but when I fracture them, they are fractured like it's not closed.
Anyone knows why or how I can check if it's closed?
The windows I extruded:
Other view:
Wireframe: