# Synopsis

PDX_MSGT gdx_GetSurfContinuity(long option, MDA_PTR db_ptr, double cont_toler[4], int *u_continuity, int *v_continuity)

# Purpose

Get the GDX surface continuity.

# Description

Determines the minimum continuity between all the segments in the GDX surface entity to within the cont_toler tolerance. For an GDX surface entity that has only one segment, the type of surface determines the level of continuity. The continuity value can vary from -1 for discontinuous to a maximium of GDX_MAX_DEG where GDX_MAX_DEG is the maximium degree supported for a GDX surface. The GDX surface must be a valid GDX definition.

# Input

## option

### GDX_GTEST

Test for G continuity for derivatives to 2

## db_ptr

The GDX surface entity database pointer.

## cont_toler

The continuity tolerance. The distance between the derivatives must be less then or equal this value to have derivative continuity .nf [0] = Model Space Distance (G0) [1] = Radian angular difference (G1) [2] = Curvature difference (G2) [3] = Normalized derivative difference .fi

# Output

## u_continuity

The level of surface U continuity (-1 to MXDEGS).

## v_continuity

The level of surface V continuity (-1 to MXDEGS).

# Tolerances

          NORMAL_MAG_TOL
          .fi

# Return

          GDX_NOERR
          GDX_INVALIDENTITYTYPE
          Low level error return
          .fi