Because their normals are facing away from the camera (and the raytrace algo’s vector). In F9, in edit mode, in MeshTools1 tab, turn on “Draw Normals” and turn up their N-size to see them.
nuh uh, It happens to me as well, I made a pretty flower and come back to it 40 minutes later to see the mesh wacked by the script. And I made sure all normals were faceing out, two sided faces were on and show both sides were also on. zich
Yeah it’s nothing to do with the normals. If you select Draw Hidden Edges (in the edit buttons under UV Calculation tab) you can see the rest of the mesh, but not the missing faces…
It seems you have to unwrap the mesh 1st before running the script to get a result.