1. Introduction to Polylines
Engineering Design Technology
Sacramento City College
Introduction to Polylines

2. Introduction to Polylines

3. Introduction to Polylines
The term polyline is composed of the words "poly" and "line."
Poly means many.
Introduction to Polylines

4. Introduction to Polylines
A polyline is
A single object that can be
Made up of one or more varied-width line segments.
Introduction to Polylines

5. Introduction to Polylines
The PLINE Command
Introduction to Polylines

6. Introduction to Polylines
Polylines are drawn with the PLINE command.
The TRACE command, is similar to the PLINE command.
Both commands can be used to draw thick lines.
PLINE has numerous advantages over TRACE
Introduction to Polylines

7. Introduction to Polylines
Polylines advantages over normal lines:
1. Polylines can be drawn as thick or tapered lines.
2. Polylines are more flexible than lines drawn with the TRACE command.
3. Polylines can be any linetype.
Introduction to Polylines

8. Introduction to Polylines
4. Polylines can be edited.
5. Closed polygons can be drawn.
6. The area or perimeter of a polyline object can be determined easily.
7. Arcs and straight lines of varying thickness can be joined as single objects.
Introduction to Polylines

9. Introduction to Polylines
The PLINE command is similar to the LINE command.
But
All segments of a polyline are treated as a single object.
Lines drawn with the LINE command, are individual segments.
Introduction to Polylines

10. Introduction to Polylines
To draw a polyline,
Pick the Polyline button from the Draw toolbar OR
Pick Polyline from the Draw pull-down menu
Type PL or PLINE at the Command: prompt:
Introduction to Polylines

11. Introduction to Polylines
Command: PL or PLINE
Specify start point: (select a point)
Current line-width is
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]: (select the next point)
Press [Enter] to end the PLINE command and return to the Command: prompt.
Introduction to Polylines

12. Introduction to Polylines
A line width of produces a line of minimum width.
Introduction to Polylines

13. Setting the Polyline Width
To adjust the Width of a PLINE
Use the Width option after you enter the PLINE command to change the line width, and
have selected the first point of the PLINE.
Introduction to Polylines

14. Introduction to Polylines
Polyline Options
Introduction to Polylines

15. Introduction to Polylines
Polyline Options
Polyline Options
Width
Halfwidth
Length
Undo
Introduction to Polylines

16. Setting the Polyline Width
Width option
Specify the starting and ending widths of the line.
The starting width value that you specify becomes the default setting for the ending width.
To keep the line the same width, press [Enter] at the second prompt.
Introduction to Polylines

17. Setting the Polyline Width
If a tapered line is desired, enter different values for the starting and ending widths.
Starting Width =
Ending Width =
Introduction to Polylines

18. Introduction to Polylines
Halfwidth Option
Halfwidth option
Allows you to specify the width of the polyline from the center to one side.
Introduction to Polylines

19. Introduction to Polylines
Length Option
Length option
Not intuitive
Allows you to draw another polyline having the same angle as the previous polyline.
To use: After drawing a polyline:
Reissue the PLINE command
Pick a starting point.
Enter the Length option
Give the desired length.
The 2nd PLINE will be parallel to the first PLINE.
Introduction to Polylines

20. Undoing Previously Drawn Polylines
Undo option
Use while inside the PLINE command
Erases the last polyline segment drawn.
Enter U at the prompt line and then press [Enter]
Each time you use the Undo option, another polyline segment is erased.
Introduction to Polylines

21. Undoing Previously Drawn Polylines
The cursor remains attached to the end of the polyline segment that was drawn before the undone segment.
You can now continue to draw additional polyline segments OR
Type U and press [Enter] again to undo another segment.
Introduction to Polylines

22. Undoing Previously Drawn Polylines
Undo Option
You can use the Undo option to remove all of the polyline segments up to the first point of the polyline.
The segments are removed in reverse order (from the order in which they were drawn).
Introduction to Polylines

23. Introduction to Polylines
The U Command
Introduction to Polylines

24. Introduction to Polylines
The U Command
The U command works in much the same way.
The U Command is not the Undo option of the PLINE command.
The U command can be used to undo any previous commands.
Introduction to Polylines

25. Introduction to Polylines
The U Command
To execute the U command:
Pick the Undo button from the Standard toolbar OR
Pick Undo from the Edit pull-down menu
Pressing the [Ctrl]+[Z] key combination
Enter U at the Command: prompt.
Introduction to Polylines

26. Introduction to Polylines
The U Command
The U command can also be activated by:
Right-clicking in the drawing area.
Selecting Undo from the shortcut menu.
AutoCAD gives you a message indicating which command was undone:
Command: U
PLINE
Command:
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27. Introduction to Polylines
The U Command
You can only undo one command at a time.
Repeated UNDO’s can be executed.
The UNDO command,
Has more options than the U command
Is more versatile than the U command.
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28. Introduction to Polylines
The REDO Command
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29. Introduction to Polylines
The REDO Command
The REDO command
is used to bring back objects that were erased with the UNDO and U commands.
Introduction to Polylines

30. Introduction to Polylines
The REDO Command
Enter REDO at the Command: prompt OR
Pick Redo from the Edit pull-down menu
Press the [Ctrl]+[Y] key combination
Pick the Redo button from the Standard toolbar to activate the command.
Introduction to Polylines

31. Introduction to Polylines
The UNDO Mark
The REDO command works only immediately after undoing something.
REDO does not bring back polyline segments that were removed using the Undo option of the PLINE command.
Introduction to Polylines

32. Filling Polylines and Traces The FILL Command
Introduction to Polylines

33. Introduction to Polylines
The FILL Command
Traces and polylines can be
Filled in, or
Shown as an outline.
These functions are controlled by the FILL command.
The FILL command has two modes, ON and OFF.
Introduction to Polylines

34. Introduction to Polylines
The FILL Command
Command: FILL
Enter mode [ON/OFF] <current>:
When the FILL is on, traces and polylines appear filled after they are drawn.
When FILL is off, traces and polylines appear as outlines, and the corners are mitered.
Introduction to Polylines

35. Introduction to Polylines
The FILL Command
After turning FILL off, REGEN to have the fill removed.
Introduction to Polylines

36. Introduction to Polylines
The FILL Command
FILL on
May slow down your computer.
If you have many wide polylines or traces in a drawing, keep FILL mode turned off.
This saves time when redrawing, regenerating, or plotting a check copy of the drawing.
Introduction to Polylines

37. Introduction to Polylines
The UNDO Command
Introduction to Polylines

38. Introduction to Polylines
The UNDO Command
The UNDO command is different from the U command.
The UNDO command offers several options that allow you to undo a single command or a number of commands at once.
Introduction to Polylines

39. Introduction to Polylines
The UNDO Command
The command sequence is as follows:
Command: UNDO
Enter the number of operations to undo or [Auto/Control/BEgin/End/Mark/Back]:
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40. Introduction to Polylines
The UNDO Command
The default option allows you to designate the number of previous command sequences you wish to remove.
If you enter 1, the previous command sequence is removed.
If you enter 2, the previous two command sequences are removed.
AutoCAD tells you which commands were undone with a message after you press [Enter].
Introduction to Polylines

41. Introduction to Polylines
The UNDO Command
Command: UNDO
Enter the number of operations to undo or [Auto/Control/BEgin/End/Mark/Back]: 2
PLINE LINE
Command:
Introduction to Polylines

42. Introduction to Polylines
The UNDO Command
There are several other types of undo operations that can be performed with the UNDO command.
Introduction to Polylines

43. The UNDO Command - Auto Option
The Auto option can be turned on or off.
When Auto option is on, any commands that are part of a group and used to perform a single operation are removed together.
When a command contains other commands, all of the commands in that group are removed as one single command.
The Auto option is on by default.
Introduction to Polylines

44. The UNDO Command - Auto Option
If Auto is turned off, each command in a group of commands is treated individually.
Introduction to Polylines

45. The UNDO Command - Control Option
The Control option allows you to specify how many of the UNDO command options you want active.
You can even disable the UNDO command altogether.
Introduction to Polylines

46. The UNDO Command - Control Option
To use the Control option:
Enter C after issuing the UNDO command:
Enter the number of operations to undo or [Auto/Control/BEgin/End/Mark/Back]: C
Enter an UNDO control option [All/None/One] <All>: (enter a control option and press [Enter])
Introduction to Polylines

47. The UNDO Command - All Option
The All suboption keeps the full range of UNDO command options active.
All is the default setting.
Introduction to Polylines

48. The UNDO Command - None Option
The None suboption disables the U and UNDO commands.
When disabled, and the U command is entered, the following prompt appears:
Command: U
U command disabled. Use UNDO command to turn it on
This prompt indicates how to reactivate the U and UNDO commands.
Introduction to Polylines

49. The UNDO Command - Auto Option
If you type UNDO at the Command: prompt, the following appears:
Command: UNDO
Enter an UNDO control option [All/None/One] <All>:
To activate the UNDO options, press [Enter] for All.
Introduction to Polylines

50. The UNDO Command - One Option
Enter 0 for the One suboption.
This setting limits UNDO to one operation only.
Command: UNDO
Control/<l>: -i
LINE
Everything has been undone Command:
Introduction to Polylines

51. Introduction to Polylines
The Auto Option
Type C at the Control/<l>: prompt to redisplay the Control suboptions.
Introduction to Polylines

52. The Begin and End Options
The BEgin and End options of the UNDO command are used together to perform several undo operations at once.
They allow you to group a series of commands and treat the entire group as a single command.
Once the group is defined, the U command is then used to remove the commands that follow the BEgin option but precede the End option.
Introduction to Polylines

53. The Begin and End Options
These options are useful if you can anticipate the possible removal of several commands that are entered consecutively.
Introduction to Polylines

54. The Begin and End Options
For example, to undo the next three commands:
Command: UNDO
Enter the number of operations to undo or [Auto/Control/BEgin/End/Mark/Back]: BE
Command: L or LINE
Command: PL or PLINEJ
Command: L or LINE-I
Command: UNDO
Enter the number of operations to undo or [Auto/Control/BEgin/End/Mark/Back]: EJ
Command: U
Introduction to Polylines

55. The Begin and End Options
The U command undoes the three commands that were executed in the previous sequence.
The BEgin option must precede the command sequence
The End option must immediately follow the last command to be undone.
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56. Introduction to Polylines
The UNDO Mark
The UNDO Mark option allows you to insert a "marker" in the undo file.
The UNDO Back option then enables you to delete commands "back" to the marker.
Introduction to Polylines

57. Introduction to Polylines
The UNDO Mark
If you do not want certain work to be undone by the Back option, enter the Mark option after completing the work:
Command: UNDO
Enter the number of operations to undo or [Auto/Control/BEgin/End/Mark/Back]: Mj
Command:
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58. Introduction to Polylines
The UNDO Mark
If you decide to remove any work, reissue the UNDO command and enter the Back option.
This will undo everything back to the marker:
Command: UNDO
Enter the number of operations to undo or (Auto/Control/BEgin/End/Mark/Back]: B
Introduction to Polylines

59. Introduction to Polylines
The UNDO Mark
If no marks have been entered, this undoes everything in the entire drawing!
AutoCAD questions your choice with the following message:
This will undo everything. OK? <Y>:
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60. Introduction to Polylines
The UNDO Mark
If you want everything that you have drawn and edited to be undone, press [Enter].
If not, enter N or NO and press [Enter], or press the [Esc] key.
Introduction to Polylines

61. Introduction to Polylines
The UNDO Mark
CAUTION Be very careful when using the UNDO Back option.
Entering this option undoes everything in the entire drawing.
You can bring back what you have undone if you
type REDO at the Command: prompt and
press [Enter] immediately after using the UNDO Back option.
Introduction to Polylines

62. Introduction to Polylines
The UNDO Mark
If you use any other command, even REDRAW, after using UNDO Back, the drawing is lost forever !
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63. Introduction to Polylines
The UNDO Mark
The REDO command can be used to restore commands removed with UNDO.
Introduction to Polylines

64. Introduction to Polylines
The UNDO Mark
The UNDO Mark option can be used to assist in the design process.
If you are working on a project and have completed a portion of the design, mark that spot with the Mark option and then begin work on the next design phase.
If anything goes wrong with this part of the design, use the UNDO Back option to remove everything back to the mark.
Introduction to Polylines