copy Curve2D getCenterPoint getLength isClosed

getLength() virtual double getLength ( ) const virtual 获取长度 获取二维曲线长度 被 ArcofCircle2D, BezierCurve2D, BSplineCurve2D, Circle2D, Hyperbola2D, LineSegment2D, NURBSCurve2D , 以及 Parabola2D 重载.