Drag onto the page, then drag one line end to ordinate origin and one to the feature. 拖到绘图页上，然后将一个线端拖到坐标原点，一个线端拖到部件。
This point, and the global Cartesian coordinate system origin, define the line along which the object is viewed while looking toward the origin. 这个点，连同全局笛卡尔坐标原点，定义了当我们朝向原点观察时，观察的视线。
