Method: the method to morph curve.

Direction: the direction for moving curve .

Constraint: the geometry constraint on the picked curve point .

Position: curve will pass the position of the target point;

Keep original tangent: curve will pass the position of the target point and keep the first derivative of the point on the original curve;

Curvature: display or hide the curvature of the curve .

Curvature on original curve: display or hide the curvature of the original curve.

Copy: copy a new curve in the database .

Annotation: display the annotation of the new point and the moving distance.

Edit: pick a curve and pick a point on the curve for moving.

Undo: undo.

Redo: redo.