# SubD.NurbsSurfaceType enum

Namespace: [Rhino.Geometry](https://developer.rhino3d.com/api/rhinocommon/namespace/rhino.geometry.md) · Assembly: [RhinoCommon](https://developer.rhino3d.com/api/rhinocommon/assembly/rhinocommon.md)

```cs
public enum SubD.NurbsSurfaceType
```

ON_SubD::NurbsSurfaceType specifies what type of NURBS surfaces are returned by ON_SubD.GetSurfaceNurbsFragments()

## Values

| Name | Value | Description |
| --- | --- | --- |
| Unset | 0 | Not a valid type. Used to indicate the type has not been set and to encourage developers to explicitly specify a type. When in doubt, specify NurbsSurfaceType::Large. |
| Large | 1 | Onee NURBS surface will be generated for each SubD quad. N NURBS surfaces will be generated for each SubD N-gon (N = 3, 5 or more). ON_Brepface may cover multiple Near extraordinary vertices, the surfaces may have lots of knots. |
| Medium | 2 | NURBS surfaces will be as large as possible without the addition of extra knots. Near extraordinary vertices, the surfaces may have lots of knots. This option is preferred when a user wants larger NURBS surfaces but not at the cost of additional NURBS control points. |
| Small | 3 | NURBS surfaces will not be merged and will have clamped knots. |
| Unprocessed | 4 | NURBS surfaces will not be merged and will have unclamped uniform knots. This is useful as a starting point for customized merging and modifying continuity at extraordinary vertices. |