1 -- File: ParabolaToBSplineCurve.cdl
2 -- Created: Thu Oct 10 14:52:24 1991
3 -- Author: Jean Claude VAUTHIER
4 ---Copyright: Matra Datavision 1991, 1992
8 class ParabolaToBSplineCurve from Convert inherits ConicToBSplineCurve
11 -- This algorithm converts a parabola into a non rational B-spline
13 -- The parabola is a Parab2d from package gp with the parametrization
14 -- P (U) = Loc + F * (U*U * Xdir + 2 * U * Ydir) where Loc is the
15 -- apex of the parabola, Xdir is the normalized direction of the
16 -- symmetry axis of the parabola, Ydir is the normalized direction of
17 -- the directrix and F is the focal length.
19 -- Convert, Parabola, BSplineCurve, 2D .
26 Create (Prb : Parab2d; U1, U2 : Real) returns ParabolaToBSplineCurve;
28 -- The parabola Prb is limited between the parametric values U1, U2
29 -- and the equivalent B-spline curve as the same orientation as the
33 end ParabolaToBSplineCurve;