Apple Motion 3 - Manual (Page 1021)

Chapter 12 Using Shapes and Masks 1021
 Control-click the edge, then choose Add Point from the shortcut menu.
Adding more control points does not immediately change a Bezier shape, unless you
drag Bezier curve points as you create them.
Adding more control points to a B-Spline shape, on the other hand, nearly always
changes its shape.
To add control points to the end of an open shape:
1 Select an open shape with the Adjust Control Points tool.
2 Option-click anywhere outside of the shape to add new control points to the end of
the shape.
3 Option-click the first point in the shape to close it (or press C).
The closed shape is not filled.
If a shape has more control points than are necessary, you can delete points from it to
make it easier to edit. This can be helpful if you animate the shape later on.
To close an open shape, do one of the following:
m Option-click the first point in the shape to close it (or press C).
The closed shape is not filled.
m Control-click a control point, then choose Close Curve from the shortcut menu.
Before adding Bezier point After adding Bezier point
Before adding B-Spline point After adding B-Spline point