The user can rotate the entire motion path about the starting point, knot A. Knot A defines the parameter space of the curve. At the default position (no rotation angles), the curve space is the world coordinate system. The path starts at the origin and moves to the right (along the x-axis). To define the path, you rotate the curve if necessary and enter the (xyz) coordinates of the knots A, B, and C. All dials are on "BODY". The knot-coordinates are distances relative to the previous knot. For example, coordinate "B_x" defines the x-distance between knot A and B. Coordinate "C_z" defines the z-distance between knot B and C. Each knot has one associated control point "aa", "bb", "cc". To define the CP's, you enter the (xyz) coordinates of the CP. Note that the CP coordinates are distances relative to the associated knot. For example, to create a nice curved path in the xy-plane between knots B and C, you choose a positive "bb_x" coordinate and a negative "cc_x" coordinate as shown in the center of the above picture. The CP coordinates define the position of the CP, i.e. the distance from the knot *and* the rotation angle (direction) of the curve tangent in the knot region. Some models have additional dials "aa_scale", "bb_scale", "cc_scale". The CP scale dials can be used to adjust the distance between the CP and the knot, and preserve the direction of the tangent.