﻿ ACIS© Library Reference - Spatial Corp.

# Entity Clearance Calculations [Entity Distance, Clash and Clearance]

Collaboration diagram for Entity Clearance Calculations:
Determine the clearance of two entities. More...

## Functions

outcome api_check_face_clearance (FACE *face1, FACE *face2, double min_clearance, double facet_resolution, SPAposition &p1, SPAposition &p2, double &min_dist, AcisOptions *ao=NULL)
Evaluates the clearance between two faces.
outcome api_check_solid_clearance (BODY *user_body1, BODY *user_body2, double min_clearance, double facet_resolution, SPAposition &p1, SPAposition &p2, double &min_dist, AcisOptions *ao=NULL)
Evaluates the clearance between two solid bodies.
outcome api_initialize_clearance ()
Initializes the clearance library.
outcome api_terminate_clearance ()
Terminates the clearance library.

## Detailed Description

Determine the clearance of two entities.

## Function Documentation

 outcome api_check_face_clearance ( FACE * face1, FACE * face2, double min_clearance, double facet_resolution, SPAposition & p1, SPAposition & p2, double & min_dist, AcisOptions * ao = `NULL` )

Evaluates the clearance between two faces.

Role: There are two modes of operation, depending upon the value of the argument `min_clearance`:

When `min_clearance` is set to zero, the minimum distance between the two faces is found.

When `min_clearance` is greater than zero, the API returns early with two points, one on either face, separated by less than this value. The points do not necessarily represent the minimum distance in this case.

Facet resolution is usually the internal (nonzero) default, which is obtained by setting `facet_resolution` to zero. Optional control of this value is supplied because it has a large effect on performance (larger tolerance means better performance).

Because faceted representations of the 3D B-spline surface approximations are used, and these facets have an accuracy of `SPAresfit`, a returned minimum distance less than `SPAresfit` is equivalent to zero.

Errors: The pointer to a face is `NULL` or does not point to a `FACE`. The specified clearance or resolution is less than zero.

Journal: Not Available

Product(s): 3D ACIS Modeler

Parameters:
 face1 first face used for the clearance check. face2 second face used for the clearance check. min_clearance minimum clearance setting. facet_resolution maximum departure of facet from a face. A value of zero causes the non-zero default to be used. p1 point on `face1` at the minimum distance (output). p2 point on `face2` at the minimum distance (output). min_dist minimum distance between the two faces (output). ao acis options.

include <clearapi.hxx>

 outcome api_check_solid_clearance ( BODY * user_body1, BODY * user_body2, double min_clearance, double facet_resolution, SPAposition & p1, SPAposition & p2, double & min_dist, AcisOptions * ao = `NULL` )

Evaluates the clearance between two solid bodies.

Role: There are two modes of operation, depending upon the value of the argument `min_clearance`:

When `min_clearance` is set to zero, the minimum distance between the two bodies is found.

When `min_clearance` is greater than zero, the API returns early with two points, one on either body, separated by less than this value. The points do not necessarily represent the minimum distance in this case.

Facet resolution is usually the internal (nonzero) default, which is obtained by setting `facet_resolution` to zero. Optional control of this value is supplied because it has a large effect on performance (larger tolerance means better performance).

Because faceted representations of the 3D B-spline surface approximations are used, and these facets have an accuracy of `SPAresfit`, a returned minimum distance less than `SPAresfit` is equivalent to zero.

Errors: The pointer to a body is `NULL` or does not point to a `BODY`. The specified clearance or resolution is less than zero.

Journal: Not Available

Product(s): 3D ACIS Modeler

Parameters:
 user_body1 first body used for the clearance check. user_body2 second body used for the clearance check. min_clearance minimum clearance setting. facet_resolution maximum departure of facet from a face. A value of zero causes the non-zero default to be used. p1 point on `user_body1` at the minimum distance (output). p2 point on `user_body2` at the minimum distance (output). min_dist minimum distance between the two bodies (output). ao acis options.

include <clearapi.hxx>

 outcome api_initialize_clearance ( )

Initializes the clearance library.

Effect: System routine

Journal: Not Available

Product(s): 3D ACIS Modeler

include <clearapi.hxx>

 outcome api_terminate_clearance ( )

Terminates the clearance library.

Effect: System routine

Journal: Not Available

Product(s): 3D ACIS Modeler

include <clearapi.hxx>