Remove Knot (NURBS Surface)

Functionality

This node performs “knot removal” procedure for a NURBS Surface.

Given a NURBS Surface object and a knot value, the node reduces the multiplicity of this knot in surface’s U- or V-knotvector. This procedure can not always be performed. In general, this procedure changes the shape of the surface. There is “tolerance” parameter, defining how much is it allowed to change the shape of the surface.

This node can work only with NURBS surfaces.

Inputs

This node has the following inputs:

  • Surface. The surface to work on. This input is mandatory.

  • Knot. The value of the knot to be removed. The default value is 0.5.

  • Count. Number of times the knot is to be removed. The default value is 1.

Parameters

This node has the following parameters:

  • Direction. This defines the parametric direction on the surface, for which to perform knot removal procedure. The available options are U and V. The default value is V.

  • Only if possible. If this flag is checked, the node will try to remove the knot Count times; if it is not possible to remove it that many times, the node will just remove it as many times as it can. If not checked, then the node will fail (become red) in such a situation, and the processing will stop. Unchecked by default.

  • Tolerance. This parameter is available in the N panel only. This defines how much is it allowed to change the shape of the surface by knot removal procedure. The default value is 10^-6.

Outputs

This node has the following output:

  • Surface. The resulting Surface object.