Synopsis

PDX_MSGT gdx_ConvertRTSToSurface(long option, MDA_PTR gdx_rts_ptr, int model, double approx_tol, int *parm_chg_flg, MDA_PTR *gdx_surface_ptr)

Purpose

Convert a GDX Rectangular Trimmed Surface entity to a GDX Surface entity

Description

Create a bounded GDX Surface that represents the trimmed portion of a given GDX Rectangular Trimmed Surface entity. The GDX surface type is consistent with the underlying surface type of the RTS. For underlying analytical surfaces Cone, Torus, Sphere, and Cylinder, the GDX Surface will be of type Rev-Surface.

Input

option

Options (not used)

gdx_rts_ptr

GDX Rectangular Trimmed Surface database pointer

model

GDX model for entity creation

approx_tol

Approximation tolerance in case the conversion is not precise. If ruled surface is trimmed in the v (linear) direction, then the boundary (new rail) curve(s) representing this trimming may not be precisely representable with any GDX entity type. Hence, approximation is required. The extracted ruled subsurface (S2(u,v)) should not deviate from the corresponding portion of the original surface (S1(u,v)) by more than approx_tol. That is, the projection distance from any point on S2(u,v) to S1(u,v) (or the reverse) should not exceed approx_tol. This tolerance corresponds to those in other GDX functions which do any type of curve/surface approximation. There is no corresponding gdx_tolerance; however approx_tol = 10 or 100 times MODEL_SPACE_PNT_TOL is a reasonable setting.

Output

parm_chg_flg

Flag indicating whether or not parameterization has changed. .nf = PDX_FALSE : parameterization has not changed = PDX_TRUE : parameterization has changed .fi

gdx_surface_ptr

GDX Surface (untrimmed) database pointer

Tolerances

      MODEL_SPACE_PNT_TOL
      COPLANAR_TOL
      TANGENT_TOL
      CURVATURE_TOL
      DERIVATIVE_TOL
      .fi

Return

      GDX_NOERR
      GDX_ENTITYNOTCURVE
      Low level error return
      .fi