Need help with understanding subdivisions

I have a problem with my subdivision workflow. I want to make a cloth with a detailed pattern as vertex paint. So I subdivided my plane, projected my vertex paint texture on highest subD level, made the deformations on the low subD level, but when I put it back to highest subD level unfortunately it is not smooth at all.
What am I doing wrong here?

Hello @zzeebee

Several possibilities I can think of:

  1. Go to the Geometry Palette and make sure the “SMT” button next to the divide button is active when subdividing. If it is not, the mesh will be subdivided but not smoothed . It will retain its faceted look.

  2. You have some portion of the mesh that is either hidden or masked. This will cause the mesh to be partially subdivided, and will also disable smoothing. Un-hide all geometry and clear any masking.

  3. The polyframe isn’t visible on the low res geometry, and the image is a little low res to be certain on the high res mesh, but make sure that your edges are not all creased at the lowest sub-D level. Creased edges will stay sharp when subdividing.


Hi @Spyndel,

Thanks for the explanation! How can I avoid a smoothing or rounding of the corners of my plane when subdividing with the smooth option on, but also without the help of creased outer edges of the plane?

2D planar geometry has some limitations in this regard because the points on the corners are not reinforced by sufficient connecting edges.

  1. Option 1 ( Outer edges creased + SMT active). The edges of the plane will stay in place but the corners will round slightly. This is because there is no reinforcing geometry to anchor the points in the corners. The degree of rounding will depend on the size of the polygons on your plane. The smaller the polygons the more the points will reinforce adjacent points, making them more resistant to smoothing.

  2. Option 2 (No Creasing + SMT active). The corners will stay sharp, but the edge of the plane will shrink inward. This again depends on the density of the points on the surface. Lower poly geometry will be more heavily affected by the smoothing algorithm.

To avoid either outcome make your plane a 3D cubic solid. This adds a third anchoring “spoke” to the corner verts. Now the edges (and corners!) of that cube can be creased and will maintain both position and crisp edges, while still smoothing any non-creased edges. Extraneous geometry can be deleted after the subdivision if desired.


Thanks again @Spyndel, this was very helpful!