The Pedit command’s Spline option (named after the spline tool used in manual drafting) offers you a way to draw smoother and more controllable curves than those produced by the Fit option. A polyline spline does not pass through the vertex points as a fitted curve does. Instead, the vertex points act asweights pulling the curve in their direction. The polyline spline only touches its beginning and end vertices. Figure 13.16 illustrates this concept.
Let’s see how using a Polyline spline curve might influence the way you edit a curve.
1. Undo the width changes you made in the previous exercise.
2. ToChange the contour into a polyline spline curve, choose Modify > Polyline.
3. Then pick the polyline to be curved.
4. At the prompt
Enter an option [Close/Join/Wi,dth/Edit vertex/Fit/Spline/
Decurve/Ltype gen/Undo]: enter 5.J. Your curve ~ to look like Figure 13.17.
5. Press..J to exit Edit Polyline.
The curve takes on a smoother, more graceful appearance. It no longer passes through the points you used to define it. To see where the points ent and to find .”out how spline curves act, do the following:
1 Make sure the NOWl/Verb Selection mode and ~ Grips featwe me tumed on.
2 click the curve. You see the vertices appear as grip
3. (lick the grip that is second from the top of the curve, as shown in the bottom image of Figure 13.18, and move the grip around. Notice how the-curve follows, giving you immediate feedback on how the curve will look.
4. Pick a point as shown in the continued image of Figure 13.18.The curve is fixed”in its new position.