-- Created on: 1994-09-01
-- Created by: Christian CAILLET
-- Copyright (c) 1994-1999 Matra Datavision
-- Copyright (c) 1999-2014 OPEN CASCADE SAS
--
-- This file is part of Open CASCADE Technology software library.
--
-- This library is free software; you can redistribute it and/or modify it under
-- the terms of the GNU Lesser General Public License version 2.1 as published
-- by the Free Software Foundation, with special exception defined in the file
-- OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
-- distribution for complete text of the license and disclaimer of any warranty.
--
-- Alternatively, this file may be used under the terms of Open CASCADE
-- commercial license or contractual agreement.

package IGESConvGeom

    ---Purpose : This package is intended to gather geometric conversion which
    --           are not immediate but can be used for several purposes :
    --           mainly, standard conversion to and from CasCade geometric and
    --           topologic data, and adaptations of IGES files as required
    --           (as replacing Spline entities to BSpline equivalents).

uses Standard, gp, TColgp, Geom, Geom2d, IGESGeom

is

    class GeomBuilder;
    ---Purpose : basic tool to build curves from IGESGeom (arrays of points,
    --           Transformations, evaluation of points in a datum)

    SplineCurveFromIGES
    	(igesent : SplineCurve from IGESGeom;
	 epscoef, epsgeom : Real;
	 result  : out BSplineCurve from Geom)
    returns Integer;
    ---Purpose : Converts a SplineCurve from IGES to a BSplineCurve from CasCade
    --           <epscoef> gives tolerance to consider coefficient to be nul
    --           <epsgeom> gives tolerance to consider poles to be equal
    --           The returned value is a status with these possible values :
    --           - 0  OK, done
    --           - 1  the result is not guaranteed to be C0 (with <epsgeom>)
    --           - 2  SplineType not processed (allowed : max 3)
    --                (no result produced)
    --           - 3  error during creation of control points
    --                (no result produced)
    --           - 4  polynomial equation is not correct (no result produced)
    --           - 5  less than one segment (no result produced)

    IncreaseCurveContinuity
    	(curve      : BSplineCurve from Geom;
	 epsgeom    : Real;
	 continuity : Integer = 2)  returns Integer;
    ---Purpose : Tries to increase curve continuity with tolerance <epsgeom>
    --           <continuity> is the new desired continuity, can be 1 or 2
    --           (more than 2 is considered as 2).
    --           Returns the new maximum continuity obtained on all knots.
    --           Remark that, for instance with <continuity> = 2, even if not
    --           all the knots can be passed to C2, all knots which can be are.
    
    IncreaseCurveContinuity
    	(curve      : BSplineCurve from Geom2d;
	 epsgeom    : Real;
	 continuity : Integer = 2)  returns Integer;

    SplineSurfaceFromIGES
    	(igesent : SplineSurface from IGESGeom;
	 epscoef, epsgeom : Real;
	 result  : out BSplineSurface from Geom)
    returns Integer;
    ---Purpose : Converts a SplineSurface from IGES to a BSplineSurface from CasCade
    --           <epscoef> gives tolerance to consider coefficient to be nul
    --           <epsgeom> gives tolerance to consider poles to be equal
    --           The returned value is a status with these possible values :
    --           - 0  OK, done
    --           - 1  the result is not guaranteed to be C0 (with <epsgeom>)
    --           - 2  degree is not compatible with code boundary type
    --                (warning) but C0 is OK
    --           - 3  idem but C0 is not guaranteed (warning)
    --           - 4  degree has been determined to be nul, either in U or V
    --                (no result produced)
    --           - 5  less than one segment in U or V (no result produced)

    IncreaseSurfaceContinuity
    	(surface      : BSplineSurface from Geom;
	 epsgeom    : Real;
	 continuity : Integer = 2)  returns Integer;
    ---Purpose : Tries to increase Surface continuity with tolerance <epsgeom>
    --           <continuity> is the new desired continuity, can be 1 or 2
    --           (more than 2 is considered as 2).
    --           Returns the new maximum continuity obtained on all knots.
    --           Remark that, for instance with <continuity> = 2, even if not
    --           all the knots can be passed to C2, all knots which can be are.

end IGESConvGeom;