Sketching with AutoCAD

No discussion of polylines would be complete without mentioning the Sketch command. Though AutoCAD isn't a sketch program, you can draw "freehand" by using the Sketch command. With Sketch, you can rough in ideas in a free-form way and later overlay a more formal drawing using the usual lines, arcs, and circles. You can use Sketch with a mouse, but it makes more sense to use this command with a digitizing tablet that has a stylus. The stylus affords a more natural way of sketching.

Here's a step-by-step description of how to use Sketch:

1. Make sure the Ortho and Snap modes are turned off. Then type Skpoly 1 . This sets the Sketch command to draw using polylines.

2. Type Sketch at the command prompt.

3. At the Record increment <0.1000>: prompt, enter a value that represents the smallest line segment you will want Sketch to draw. This command approximates a sketch line by drawing a series of short line segments. So the value you enter here determines the length of those line segments.

4. At the Sketch . Pen eXit Quit Record Erase Connect: prompt, click the Pick button and then start your sketch line. Notice that the message <Pen down> appears, telling you that AutoCAD is recording your cursor's motion.

   Tip  

   You can also start and stop the sketch line by pressing the P key.

5. Click the Pick button to stop drawing. The message <Pen up> tells you that AutoCAD has stopped recording your cursor motion. As you draw, notice that the line is green. This indicates that you have drawn a temporary sketch line and have not committed the line to the drawing.

6. A line drawn with Sketch is temporary until you use Record to save it, so turn the sketch line into a polyline now by typing R .

7. Type X to exit the Sketch command.

Here are some of the other Sketch options:

Connect     Enables you to continue a line from the end of the last temporary line drawn. Type C and then move the cursor to the endpoint of the temporary line. AutoCAD automatically starts the line, and you just continue to draw. This works only in the <Pen up> mode.

Period (.)     Enables you to draw a single straight-line segment by moving the cursor to the desired position and then pressing the period key. This works only in the <Pen up> mode.

Record, Erase, Quit, and Exit     Control the recording of lines and exiting from the Sketch command. Record is used to save a temporary sketched line; after a line has been recorded, you must edit it as you would any other line. With Erase, you can erase temporary lines before you record them. Quit ends the Sketch command without saving unrecorded lines. On the other hand, the Exit option on the Sketch menu automatically saves all lines you have drawn and then exits the Sketch command.