The point can be either on the curve or off the curve. If it is on the curve, the U Position is the only control of its location. The U Position specifies a location along the curve (based on the curve's local U axis). There are three ways to displace the point's location relative to the U position.
To create a dependent curve point:
While a curve point sub-object is selected, the Curve Point rollout appears.
Specifies the point's location on the curve or relative to the curve.
When on, the point lies on the curve at the U Position.
Moves the point according to a relative (object space) X,Y,Z location.
This is relative to the U Position.
Specify the object space location of the offset curve point.
Moves the point along the direction of the curve's normal at the U Position.
Specifies the distance along the curve's normal. Negative values move the point opposite to the normal.
Moves the point along the tangent at the U Position.
Specifies the distance from the curve along the tangent.
Offset, normal, and tangent displacement of a curve point
Controls in this group let you trim the parent curve.
When on, trims the parent curve against the curve point's U position. When off (the default), the parent isn't trimmed.
When on, trims in the opposite direction.
(Only at modification time.) Lets you replace the parent curve. Click the button, then click the new curve on which to base the curve point.