# To Object

[Origin on Object] command moves CPlane's origin to a point on an object. Optionally, cplane rotaion is provided to allign to the object's normal or tangent

WhileSpecify the object to move the CPlane' origin on prompt is displayed, select an object desired(point, curve, or surface).

When the object selected is a point, the origin of CPlane is moved to the point. The direction of CPlane stays unchanged.

When the object is a curve or a surface, cplane rotation is optional. the option of "move only" and "rotation too" is toggle, and changed by typing the key M. The rotaiton is executed as:

- When the object is a curve, the Frenet frame(Tangent, Normal, Binormal of the curve at the specified point) defines the cplane's direction. Only the normal of the cplane can be designated by KB key T,N,or B. The orizontal and vertical direction is defined from the order of (T,N,B), e.g. typing B is (T,N) is (horizontal, verticla).

- When the object is a surface, the parameter line directions and the normal defines the CPlane direction. Let (Tu, Tv, N) be (tangent along u-parameter line, tangent along v-parameter line, normal), then according to the KB key of

- T: Tu is normal and (Tv,N) is (horizontal, vertical).

- N: N is normal and (Tu,Tv) is (horizontal, vertical).

- B: Tv is normal and (N, Tu) is (horizontal, vertical).