Editing NURBS Curves

Once you've laid out your curve, you may wish to insert points into it or add points to the end of the curve for extra detail.

To add edit points to a curve:

1.	Right-click a curve, and select Curve Point from the marking menu (Figure 7.15). Figure 7.15. The right-click marking menu provides component display options.
2.	Click the curve where you wish to insert a new EP.
3.	Choose Edit Curves > Insert Knot. A new EP is created in the spot you've designated. New CVs are automatically created to adjust this new point (Figure 7.16). Figure 7.16. The original curve with a curve point selected, and the curve after Insert Knot has been performed.

Curve direction

As stated earlier, each curve has a direction, called the U direction. Sometimes you'll want to reverse a curve's direction because you're getting undesirable surfaces from the curves (Figure 7.17).

Figure 7.17. Curve direction can cause unwanted surface problems. It's best to keep all curves of the same surface facing in the same direction.

To reverse a curve's direction:

1.	Select a curve in object mode.
2.	Choose Edit Curves > Reverse Curve Direction (Figure 7.18). Figure 7.18. Select Edit Curves > Reverse Curve Direction to change the direction of a curve.
3.	Press to view the new curve direction in component mode (Figure 7.19). Figure 7.19. The curve on top shows the direction before it was reversed; the curve beneath it shows the direction after the curve has been reversed.