1 -- Created on: 1991-10-10
2 -- Created by: Jean Claude VAUTHIER
3 -- Copyright (c) 1991-1999 Matra Datavision
4 -- Copyright (c) 1999-2014 OPEN CASCADE SAS
6 -- This file is part of Open CASCADE Technology software library.
8 -- This library is free software; you can redistribute it and/or modify it under
9 -- the terms of the GNU Lesser General Public License version 2.1 as published
10 -- by the Free Software Foundation, with special exception defined in the file
11 -- OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
12 -- distribution for complete text of the license and disclaimer of any warranty.
14 -- Alternatively, this file may be used under the terms of Open CASCADE
15 -- commercial license or contractual agreement.
17 class EllipseToBSplineCurve from Convert inherits ConicToBSplineCurve
20 -- This algorithm converts a ellipse into a rational B-spline curve.
21 -- The ellipse is represented an Elips2d from package gp with
22 -- the parametrization :
24 -- Loc + (MajorRadius * Cos(U) * Xdir + MinorRadius * Sin(U) * Ydir)
25 -- where Loc is the center of the ellipse, Xdir and Ydir are the
26 -- normalized directions of the local cartesian coordinate system of
27 -- the ellipse. The parametrization range is U [0, 2PI].
29 -- Convert, Ellipse, BSplineCurve, 2D .
32 ParameterisationType from Convert
34 raises DomainError from Standard
39 Parameterisation : ParameterisationType from Convert
40 = Convert_TgtThetaOver2 ) returns EllipseToBSplineCurve;
41 --- Purpose : The equivalent B-spline curve has the same orientation
45 Create (E : Elips2d; U1, U2 : Real;
46 Parameterisation : ParameterisationType from Convert
47 = Convert_TgtThetaOver2 ) returns EllipseToBSplineCurve
49 -- The ellipse E is limited between the parametric values U1, U2.
50 -- The equivalent B-spline curve is oriented from U1 to U2 and has
51 -- the same orientation as E.
54 -- Raised if U1 = U2 or U1 = U2 + 2.0 * Pi
58 end EllipseToBSplineCurve;