1

On Default Cube, select face, Inset it, Extrude it 'inside' the cube, add Bevel and Subdivision. This is the result.

I recently switched to the latest Blender version, and I could be wrong, but I don't remember the same behaviour in older version.

This is Default Cube, no extra vertices, no wrong face orientation.. And on Cylinder the process is working as expected. If I switch Subdivision to Simple, it looks as expected, but somewhat rough.

Why is that? What am I not understanding? enter image description here

vertexed
  • 11
  • 1

1 Answers1

4

Catmull-Clark Subdivision Surface smoothens the mesh by interpolating values of nearby vertices. If there's not enough holding loops this smoothing can actually create sharp geometry like so:

The key is to have quads wherever normals change, as well as to have the quad loops flow with a consistent way to the smoothed mesh:

Markus von Broady
  • 36,563
  • 3
  • 30
  • 99