Splines

Command: SPLINE

A spline is an open or closed smooth curve defined by a set of points. You can use splines to draw curved shapes, which cannot be drawn as a polyline.

Drawing splines

Do one of the following
Click the Spline tool button () on the Draw toolbar.
Choose Spline in the Draw menu.
Type spline in the command bar, then press Enter.

The command bar reads: First point of spline:

Specify the first point of the spline.
Define the second point of the spline.
The command bar reads: Close/Fit Tolerance/<next point>:
A prompt menu displays.
(option) Repeat step 3 to define more points.
Right click to stop adding more points.
The command bar reads: Select starting tangent point:
A line that is tangent to the spline displays dynamically from the start point of the spline.
Click to define the curve of the spline.
The command bar reads: Select ending tangent point:
A line that is tangent to the spline displays dynamically from the start end of the spline.
Click to conclude the spline command.
(option) Right click to restart.

NOTES

The red dashed lines in the above images represent the polyline through the control points of the spline.
The SPLFRAME (Spline Frame) settings variable defines whether the control polygon displays for splines and spline-fit polylines.