Synopsis

PDX_MSGT igeo_Check104QForm(long option, MDA_PTR db_ptr, double zero_tolerance, int *conic_form)

Purpose

Check IGES conic entity(104) coefficients for valid form.

Description

Performs the check specified in the IGES standard for the form of the IGES conic entity. The check is performed by computing 3 Q values(Q1, Q2, Q3) and based on the following determines the form of the conic: Q2 > 0 and Q1 * Q3 < 0 - conic_form = IGEO_ELLIPSE Q2 < 0 and Q1 != 0 - conic_form = IGEO_HYPERBOLA Q2 = 0 and Q1 != 0 - conic_form = IGEO_PARABOLA

The test for <=> 0 is tested to the zero_tolerance value where zero_tolerance is a value close to 0.0. If a valid conic_form can not be determined the conic_form is set to IGEO_UNKNOWNCONIC.

Input

option

The option( Not Used)

db_ptr

The IGES 104 entity database pointer

zero_tolerance

The close to zero tolerance value

Output

conic_form

The form of the conic IGEO_ELLIPSE - conic is an ellipse IGEO_HYPERBOLA - conic is a hyperbola IGEO_PARABOLA - conic is a parabola IGEO_UNKNOWNCONIC - conic form is unknown

Return

      IGEO_NOERR
      Low level error return
      .fi