Modify Curve Update Parameters

The Update Parameters command enables you to modify the length of a curve by changing the value of the parameter that describes it (every curve is described by a parametric equation as a function of a u parameter whose value ranges from 0 to 1).

First select the curves to be modified (the Curves item in the selection list will turn to green) and then end selection by right-clicking and selecting Continue in the context menu.

Appropriate handles will then show up so as to enable you to change the endpoints either interactively by dragging or by typing in the new values (Start parameter and End parameter).

• If you indicate a range of values smaller than the original one, the curve is "shortened" but its shape left unchanged.
• Instead, when you extend the parameter range by increasing the maximum value (value > 1) or lowering the minimum value (value < 0), or both of these, notice that, although neither the number of arcs nor the number of control points, nor even the original part of the curve is modified, the result is predictable in the case of specialized curves (circular arcs, ellipses, etc.), while large extensions may lead to unexpected results in the case of NURBS.

The Associative Mode check box enables you to create curves which retain a link to the surfaces/curves they derive from.

	When the check box is selected, the resulting curves will be associative. The new curve will retain a link to the entities it derives from. A specific node displaying both the original entities and the resulting associative curve will be added to the Model Structure.
	When the check box is cleared, the resulting curves will not be associative.

Try to ...

• Modify the parameter of a curve