Constructing Splines

A Spline is a smooth curve that is fit to a set of points. You can create a non-uniform rational B-spline or NURBS curve for any number of fit points. You can also fit the Spline to the specified points within a specified tolerance value.

To construct Splines:

1. Click Draw > Spline (or type Spline).
2. In the graphics area, click to define the:
1. Start point of the Spline or enter a value.
2. Next fit point of the Spline or enter a value.
3. Do one:
• In the graphics area, click to enter successive points to continue the Spline.
• Specify the Fit tolerance option to define a fit tolerance and click or enter other spline points.
4. To conclude the Spline, do one:
• Press Enter and click in the graphics area to define the tangents at the start and end points of the curve.
• Specify the Close option to close the Spline curve and click in the graphics area to define the tangent to the curve at the closing point.

   

  After you specify a fit tolerance, the fit tolerance applies to all fit points until you change it. Setting the fit tolerance to zero forces the Spline to pass through the fit points.

Note: You can use EditPolyLine to convert a PolyLine to a Spline.

Access

Command: Spline

Menu: Draw > Spline