# Synopsis

PDX_MSGT gdx_FaceNurbSurfToNurb(long option, int surf_deg, double tolerance, int maxits, MDA_PTR gdx_face_ptr)

# Purpose

Convert face surface from NURBS to NURBS, if criteria is not met.

# Description

The NURBS surface in a face will be converted to a new NURBS surface.

If non-NURBS data is encountered, nothing will be done The surf_deg, tolerance and maxits are used during the approximation/conversion.

# Input

## option

### GDX_NURBS_CLAMP

Non clampped nurb surface will be clamped. This option can not be used with GDX_NURBS_MAKE_UNIFORM

### GDX_NURBS_REPARAM

Nurb surface will be reparametized between 0.0 and 1.0. This option can not be used with GDX_NURBS_MAKE_UNIFORM

### GDX_NURBS_MAKE_UNIFORM

Nurb surface will be approximated to uniform knots nurb surface. This option can not be used with GDX_NURBS_CLAMP, GDX_NURBS_REPARAM or GDX_NURBS_MAKE_BEZIER.

### GDX_NURBS_NONRATIONAL

Rational nurb surface will be approximated to non-rational nurb surface. This option can not be used with GDX_KEEPRRAT

### GDX_NURBS_MAKE_BEZIER

Non-bezier nurb surface will be approximated to bezier nurb. This option overides GDX_NURBS_CLAMP and GDX_NURBS_NONRATIONAL options.

### GDX_NURBS_FORCE_DEGREE

Nurb surface will be converted/approximated to the specified degree. This option can not be used with GDX_NURBS_REDUCE_DEGREE or GDX_NURBS_ELEVATE_DEGREE.

### GDX_NURBS_REDUCE_DEGREE

Nurb surface exceed the specified degree will be approximated to the degree specified. This option can not be used with GDX_NURBS_FORCE_DEGREE or GDX_NURBS_ELEVATE_DEGREE.

### GDX_NURBS_ELEVATE_DEGREE

Nurb surface degree less than the specified degree will be converted to the degree specified. This option can not be used with GDX_NURBS_FORCE_DEGREE or GDX_NURBS_REDUCE_DEGREE.

### GDX_KEEP_DEGREE_1

When conversion take place, degree 1 will be kept.

### GDX_KEEPRAT

Keep rational when elevating the degree This option can not be used with GDX_NURBS_NONRATIONAL

## surf_deg

The degree to approximate the GDX NURB surfaces when GDX NURB are converted with any DEGREE option specified.

## tolerance

The tolerance for approximating the GDX NURB surface, if needed.

## maxits

Maximum number of iterations during approximation

## gdx_face_ptr

The database pointer for the GDX face entity

# Output

## gdx_face_ptr

The database pointer for the GDX face entity

# Tolerances

          MODEL_SPACE_PNT_TOL
          .fi

# Return

          GDX_NOERR
          GDX_INVALIDMODEL
          Low level error return
          .fi