copy Curve isClosed Reverse

copy() virtual Geometry * copy ( void  ) const virtual 实现了 Geometry. 被 ArcofCircle, ArcofEllipse, BezierCurve, BSplineCurve, Circle, Ellipse, Hyperbola, Line, LineSegment, NURBSCurve, Parabola , 以及 PolyLine 重载.