A polyline is a series of line and/or arc segments joined together in one entity or object. In addition to the regular AutoCAD Draw Polyline command (PL), there is this Carlson command that has several key features and options. This command allows you to draw a polyline entity in a variety of ways, including: Continue, Extend, Follow, Arc, Direction, Close, Pick point or point numbers. This dialog shown below automatically appears when you run the command.
The Show Options on Startup dialog
will appear every time the command is run, unless this is turned
off. If you do not want it to come up, then toggle it off. In this
dialog you can set the elevation of the polyline, as well as the layer
it will appear on.
Offset from centerline allows
you to make another choice. First, a unique command line appears.
[Continue/Extend/Follow/Offset/Options/<Pick
point or point numbers>]:
Auto-Zoom mode
regenerates the screen as you draw your polyline, to give you
the best
view as you are working. Always
means it will always regenerate the screen. Proximity regenerates the screen
according to the Proximity Zoom
Level % value. Never toggles
off this feature. The Elevation
of the polyline can be set
here. The default is 0. If it is off, then the last settings will
apply. To get the box
back, choose O for Options on the command line.
If Use Current Drawing Layer is on, the layer of the new polyline will be the current layer. If the current layer is not used, the Layer option allows you to Select from a list or Pick from the screen.
There
are three options under Auto-Zoom Mode.
Never will not zoom to the
last point picked.
Proximity will zoom to the
percent proximity set below. Always will
always zoom center on every point.
If
the Proximity Auto-Zoom mode
is checked, the percent of the proximity
is set in the box on the right.
Annotate closed pads, when
checked, will make available the Settings button on the right side.
When Settings is chosen, the Annotate pad dialog appears. Here is where
you can enter in values that will result in annotation for the closed
polyline.
With regards the options available on the command line, they are
explained as follows:
Continue allows you to run Arc, Direction, Close, Extend, or Follow for an existing polyline.
Extend allows you to extend an existing polyline by picking or entering in a distance.
Follow allows you to match the path of your polyline with an existing polyline. You are prompted to select the point in which your polyline first intersects with the existing polyline and the point in which it exits. If the existing polyline is a closed polyline than you will be prompted to approve the direction in which your polyline follows the existing closed polyline.
Options brings up the Polyline 2D Options dialog that appears when you first run the command, unless Offset from centerline is checked, in which case the letter indicates this feature, and a centerline will be requested.
Pick point allows you to pick a point on the screen to start your polyline.
Point numbers allows you to enter in coordinates to start your polyline.
Arc allows you to draw an arc by Arc length/Chord/Radius/Second point in your polyline. The + or - activates an additional prompt option that allows you to plot line segments at a 90 degree deflection angle from the last line. This is useful for plotting buildings.
Distance for an angle code, a backsight point, an angle (dd.mmss), and a distance to draw your polyline.
Close will connect the ends of your polyine making it a closed polyline.
[Continue/Extend/Follow/Options/<Pick point or point
numbers>]: pick a point
Segment length: 0.00, Total length: 0.00
[Arc/Close/Direction/Extend/Follow/Line/Undo/<Pick
point or point numbers>]: pick
a point
Segment length: 3.83, Total length: 3.83
[Arc/Close/Direction/Extend/Follow/Line/Undo/<Pick
point or point numbers>]: pick a point
Segment length: 2.94, Total length: 6.77 press Enter to end
Pulldown Menu Location: Draw
Keyboard Command: 2DP
Prerequisite: None
File Names: \lsp\poly3d.arx