# Synopsis

PDX_MSGT gdx_InsertKnotSurface(long option, T_GDX_NURB_SURF *sur, double uv, int num_ins, int *kmult)

# Purpose

Insert a knot into a surface multiple times.

# Description

Insert the knot uv into the surface pointed to by sur num_ins times. The total multiplicity of uv (current plus num_ins) will not exceed the degree of the surface in the corresponding parameter (u or v). This routine checks for this case, and if applicable, adds uv fewer than num_ins times. uv may be either a u- or a v-knot (option).The pointer sur does not change, but the original surface is destroyed (new control points and knots are allocated).

# Input

## option

### GDX_UKNOT

If set, then uv is a u-knot; otherwise, uv is a v-knot.

## sur

Pointer to the GDX NURB Surface to which the knot is to be added.

## uv

Knot to be added (assumed to be in the parameter range given by the knot vector). May be either a u- or v-knot (see option).

## num_ins

Number of times to add uv.

# Output

## kmult

The multiplicity of uv after insertion.

## sur

Pointer not changed, but contents of structure pointed to by sur are changed.

# Tolerances

          KNOT_TOL
          .fi

# Return

          GDX_NOERR
          Low level error return
          .fi