Part 5: Meet the Family - Complex 2D Objects


Polygons are closed polylines comprised of a minimum of 3 and a maximum of 1,024 equal-length sides.

Two ways to draw: Inscribed in and circumscribed about a circle.

Drawing Polygons

A polyline is a connected series of arcs and lines that is treated as a single object, See figure at right.

Drawing Spline Curves

A Spline is a smooth curve that passes through or near a set of points that influence the shape of the curve. See figure at right.

Drawing Donuts

Donuts are rings or solid, filled circles that are created as closed, wide polylines. See figure below.

Creating Filled Areas

Filled areas are objects such as a rectangle, triangular, or quadrilateral areas filled with any solid color, textured pattern or image. See following examples.


CAD allows the user to create complex objects which are composed of multiple objects and all are treated as a single object.

For example, in drawing a “Rectangle” each side is regarded as a single object, but selecting any one side of the rectangle for editing causes the entire rectangle to be selected.

For more information, along with illustrations/animations/short quiz, please Click Here.

Part 5: Meet the Family - Complex 2D Objects