Move a point on a curve to touch another curve

1. Use Pick > Edit Point to select the edit point you want to move.
2. Click Transform > Move .
3. Hold and (Windows) or and (Mac) to turn on curve snapping.
4. Click the curve you want to move the point onto. You can drag the point along the curve.

Stretch a curve so it touches another curve

1. Choose Curve Edit > Modify > Stretch .
2. Select the curve you want to stretch

   Two control handles appear at the ends of the curve.

   

3. Click on the handle you want to touch to the other curve.

   The handle turns white.

4. Hold and (Windows) or and (Mac) to turn on curve snapping.
5. Click on the other curve to snap the handle to it.
6. Drag the handle along the curve.

How do I use the curve stretch handles?

• To change the number of handles, press the - Handles or + Handles buttons. The minimum number of handles is 2. The maximum number is equal to the curve’s degree + 1. For example, a degree 3 curve cannot have more than 4 handles.
• To change a handle’s location along the curve, click and drag the purple triangle attached to it.

How do I use the tangent manipulator?

• Press the Tangent On button to bring up the manipulator on the active handle.
• Use the manipulator’s arrow head to modify the position of the curve at that point by sliding it along the tangent.
• Use the manipulator’s square to scale the tangent.
• Use the manipulator’s dotted arcs to rotate the tangent around the X, Y or Z axes.
• Use the manipulator’s axes lines to orient the tangent along the X, Y or Z axes.
• Press the Tangent Off button to remove the manipulator.

  

What if...?

I can’t see edit points on the curves?

• You may have turned off the display of edit points, either for this object or the entire scene.
• The curve may have only one span.

Transform a curve so it intersects two other curves

The Curve Edit > Modify > Transform Curve tool provides a direct way of positioning or transforming a curve so that it intersects two rail curves.

Positioning and intersecting a curve can be done in two ways:

• By moving the curve so that it intersects the first rail, then “rocking” (rotating) it so that it intersects the second rail.
• By “dilating” (scaling) the curve, while preserving its shape characteristics, so that it intersects both rails. This is different from the Curve Edit > Modify > Stretch tool, which changes the curvature characteristics of the curve as it stretches it.

How do I use the rotation manipulator?

The rotation manipulator appears when you are in Rotate mode (Rotate button depressed). It has three axes (X, Y and Z), and a circle along which the selected handle on the curve rotates. By default, this circle is drawn in the plane of the curve.

• Click on one of the three axes to change the plane of rotation to the plane perpendicular to that axis.

  The circle is redrawn in that plane.

  NoteCurrently, the only way to go back to using the plane of the curve as plane of rotation is to re-enter the tool, click the curve and then click the Rotate button again.