Datasheet

UNDERSTANDING HOW COMMAND OPTIONS WORK

When you see a set of options in the Command window, note their capitalization. If you

choose to respond to prompts using the keyboard, these capitalized letters are all you need

to enter to select that option. In some cases, the first two letters are capitalized to differentiate

two options that begin with the same letter, such as LAyer and LType.

3. Now select a point for the center of the arc as shown in Figure 1.11. The prompt Specify

start point of arc: appears. You also see a rubber-banding line from the center point you

just selected to your cursor.

If you point directly to the right, you see that the rubber-banding line snaps to an exact hor-

izontal orientation, and you see a tool tip appear at the cursor. This is a feature called Polar

Tracking vector, and it helps you to draw in exact horizontal and vertical directions much like

a T square and a triangle. The tool tip shows your cursor’s location relative to the center

point you just selected. It displays this information in what is known as a polar coordinate.

You can learn more about polar coordinates in Chapter 2.

4. With the rubber-banding line pointing to the right, click the left mouse button to select a

point, as shown in Figure 1.11. The prompt Specify end point of arc or [Angle/chord

Length]: appears.

5. Move the mouse, and a temporary arc appears, originating from the start point of the arc that

you just selected and rotating about the center of the arc.

As the prompt indicates, you now have three options. You can enter an angle, a chord

length, or the endpoint of the arc. The prompt default, to specify the endpoint of the arc, lets

you select the arc’s endpoint. Again, the cursor is in Point Selection mode, telling you it is

waiting for point input. To select this default option, you need only select a point on the

screen indicating where you want the endpoint.

Figure 1.11

Using the Arc

command

Finally, click here for the endpoint.

Click here for the arc center.

Then click here for

the start point.

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