The Straight and Narrow: Lines, Polylines, and Polygons

As I harp on a bunch of times elsewhere in this book, CAD programs are for precision drawing, so you'll spend a lot of your AutoCAD time drawing objects composed of straight-line segments. This rest of the chapter covers these commands:

  • LINE (L): Draws a series of straight line segments; each segment is a separate object.
  • PLINE (PL): Draws a polyline — a series of straight and/or curved line segments. (Yes, I'm cheating a bit here — curvy things are covered in Chapter 9 — but I didn't want you to have to read about one command in two different places!) All the segments remain connected to each other as a single object.
  • RECTANG (REC): Draws a polyline in the shape of a rectangle.
  • POLYGON (POL): Draws a polyline in the shape of a regular polygon (that is, a closed shape with all sides equal and all angles equal).

The following additional straight-line drawing commands are also available in AutoCAD:

  • RAY: Draws a line that starts at a point and just keeps on going; a ray therefore is a line that extends infinitely in one direction.
  • XLINE (XL): Draws a line that passes through a point and extends infinitely in both directions.

image The RAY and XLINE commands are used to draw construction lines that guide the construction of additional geometry. Drawing construction lines is less common in AutoCAD than in some other CAD programs. ...

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