Drawing polylines

A polyline is an open or closed sequence of connected line and/or arc segments, which are treated as a single entity. Each segment of a polyline can have a width that is either constant or tapers over the length of the segment.

The PLINE command interactively creates open and closed polylines entering points.

The BOUNDARY and -BOUNDARY commands create closed polylines from an enclosed area, defined by other entities.

The JOIN command creates polylines from a series of connected lines, polylines and arcs.

The Polyline tool is available on:

  • The Draw menu.
  • The Draw toolbar.
  • The Draw ribbon panel.
  • The Draw tab of the No Selection Quad.

The Thickness property specifies the height of a polyline. If Thickness = 0 (zero) there is no visual difference between polylines and a series of lines and/or arcs.

The default thickness is saved through the THICKNESS system variable.

The Elevation property specifies the distance between the plane of the polyline and the XY-plane of the WCS (World coordinate system).

THICKNESS = 0 (left), THICKNESS = 50 (middle), ELEVATION = 50 (right)

When a polyline is edited, you can modify the entire polyline or change individual segments and you can add or remove vertices.

Zero width polyline Constant width polyline Tapered width polyline
  • When FILLMODE = 0, only the outline of all filled entities, such as wide polylines and planes, displays.
  • Depending on the value of the GRIPS system variable polylines have grips on their endpoints and vertices (GRIPS = 1) or endpoints, vertices and vertex midpoints (GRIPS=2)
  • Polylines have a direction, which can be modified by the Reverse Direction option of the PEDIT (polyline edit) command.

General procedure

  1. Launch the PLINE command.

    Prompts you: Select start of polyline or [Follow] <Last point>:

  2. Specify a point.

    Prompts you: Set next point or [draw Arcs/Distance/Follow/Halfwidth/Width]:

  3. Specify a point.

    Prompts you: Set next point or [draw Arcs/Distance/Follow/Halfwidth/Width/Undo]:

  4. Specify a point.

    Prompts you:

    Set next point or [draw Arcs/Close/Distance/Follow/Halfwidth/Width/Undo]:

  5. Keep specifying points.

  6. Do one of the following:

    • Choose the Close option to connect to the start point and create a closed polyline.
    • Choose the Undo option to remove the previous vertex.
    • Right click or press Enter to stop.

Creating boundary polylines

  1. Launch the BOUNDARY command.

    The Boundary dialog box displays.

  2. Click the Pick points in boundaries button.

    The dialog box closes.

  3. Click in the area where you want to create the boundary polyline.

    The boundary polyline highlights.

  4. (option) Keep picking points to create more boundary polylines.

  5. Right click to accept the polyline(s).

    The Boundary dialog box opens again.

  6. Click the OK button.

    The polyline(s) is (are) created.