Autodesk 057B1-41A111-1001 - AutoCAD LT 2010, User Manual

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Draw Splines
A spline is a smooth curve that passes through or near a set of points that
influence the shape of the curve.
SPLINE and BLEND create curves called nonuniform rational B-splines (NURBS),
referred to as splines for simplicity.
By default, a spline is a series of blended curve segments of degree 3 (also
called cubic) polynomials. Cubic splines are the most common, and mimic
the splines that are created manually using flexible strips that are shaped by
weights at data points.
In the following example, SPLINE was used to create the highlighted boundary
of the concrete walkway.
BLEND was used to create splines between lines and arcs for a golf course
design. The resulting splines are tangent to the selected lines and curves
without changing the lengths of the selected objects.
Understand Control Vertices and Fit Points
You can create or edit splines using either control vertices, or fit points. The
spline on the left displays control vertices along a control polygon, and the
spline on the right displays fit points.
186 | Chapter 6 Create and Modify Objects