absoluteValue angle calFixedAngleAndDistanceAndOnLinePoint calFootOfPerpendicular Cross DistanceToLine DistanceToLineSegment DistanceToPlane Dot epsilon findPointOnLine GetAngle getDotProduct IsEqual IsNull IsOnLineSegment IsOnLineSide isParallelX isParallelY isParallelZ Length magnitude2D maximum minimum Move moveAlongLinePt MoveX MoveY MoveZ Normalize num_type operator!= operator% operator& operator* operator* operator*= operator+ operator+= operator- operator- operator-= operator/ operator/= operator< operator= operator= operator== operator[] operator[] Perpendicular ProjectToLine ProjectToPlane ProjectToPlane RotateX RotateY RotateZ Scale ScaleX ScaleY ScaleZ Set SetX SetY SetZ Sqr traits_type TransformToCoordinateSystem Vector3 Vector3 Vector3 x y z ~Vector3

IsNull() template<class _Precision > bool IsNull ( ) const 检查向量是否为零向量 检查向量是否为零向量。 返回 如果所有分量都等于 0.0，则返回 true，否则返回 false