# Synopsis

PDX_MSGT gdx_RevSurfGeneratrixParms(long option, MDA_PTR curve_ptr, MTH_3DPNT center, MTH_3DVEC vec_axis, double start_angle, double *angle, MTH_3DVEC vec_seam)

# Description

The parameters of the generatrix curve of a revolving surface will be found. The parameters include the sweeping angle of the the curve on a plane that is perpendicular to the revolve axis, and a vector that is perpendicular to the axis and goes through a point on the seam if the sweeping angle is zero, otherwise NULL.

The generatrix curve is a single entity curve.

# Input

## option

Options (not used)

## curve_ptr

The Generatrix curve

## center

A point on the revolving axis

## vec_axis

The vector of the revolving axis

## start_angle

The start angle of the revolving surface

# Output

## angle

The sweeping angle

## vec_seam

The vector that is perpendicular to the revolve axis and passes through a point on the seam if angle is zero, otherwise, NULL.

# Return

          GDX_NOERR
          Low level error return
          .fi