# Synopsis

PDX_MSGT gdx_FaceExtractSurface2(long option, double p0, double p1, double devtol, PDX_BOOL *parm_change, MDA_PTR gdx_face_ptr)

# Purpose

Extract the surface in a face in either U or V.

# Description

Extract a surface in a face. The surface will be replaced in the face. The original surface will be deleted if this face is the only parent. If a parm change occurs, then the parm curves will be deleted Ths function is based on gdx_FaceExtractSurface. However, it will do the extraction given only U or V parm values. This is needed down in the splitting code which works on either U or V.

# Input

## option

### GDX_SPLIT_U

Extract given U parm values.

### GDX_SPLIT_V

Extract given V parm values.

## p0

The extraction start parameter.

## p1

The extraction end parameter. If p0 > p1, then the surface must be closed in the p-direction, and the resulting subsurface will include the p-seam (and portions of the surface to either side of the u-seam).

## devtol

Tolerance used during extraction of surface

## gdx_face_ptr

DB pointer of face with surface to be extracted

# Output

## parm_change

Flag indicating the parameterization of the new surface is different than the old surface. Parm curves will be deleted from the face.

## gdx_face_ptr

Face with extracted surface

# Tolerances

          MODEL_SPACE_PNT_TOL
          PARM_SPACE_PNT_TOL
          ANGLE_TOL
          ZERO_TOL
          .fi

# Return

          GDX_NOERR
          GDX_INVALIDMODEL
          Low level error return
          .fi