Polyline

AutoCAD PLINE Command

How to Draw a Polyline in AutoCAD

All segments of a Polyline are connected to create one drawing object.

If all segments of a polyline are lines, drawing a polyline is done exactly the same as drawing a line, and all segments of the polyline are connected to create one drawing object. Arcs can also be included as part of a polyline. To include an arc as a segment of the polyline, after completing one segment of the polyline and while the command is still active, enter ARC (A) at the command line. To draw line segments, enter LINE (L) at the command line if the prompt is expecting an arc to be drawn.

All Segments of a Polyline Act Together

When a polyline is selected, all snap boxes for every segment of the polyline are shown. If you want to copy, move, or change any property of the polyline, when one of the elements of the polyline is selected, the entire polyline is selected. All segments will be copied, moved, or have their properties changed because all segments of the polyline collectively make one object.

Polylines can be nearly any shape, and all segments are connected together to make one object. This can be used to your advantage when both creating and modifying a polyline. For example, in the image below, the OFFSET command is used. The original polyline is the outer object, and the new polyline is the inner object. Notice how all segments of the polyline offset together, including the vertices of each intersection of two line segments.

Open and Closed Polylines

Polylines can either be open or closed. An open polyline is simply a series of lines and arcs connected together to form the polyline with the first and last vertex being in different locations. A closed polyline differs from an open polyline because the first and last vertex are in the same location. Shown below are two polylines, one is closed and one is open. The closed polyline has a straight line segment connecting the first vertex to the last vertex, while that line segment does not exist in the open polyline.