Graphics Programs Reference
In-Depth Information
2.
Click the line you just created—the one that crosses through the ellipse—and press ↵ to
finish your selection.
3.
At the Select object to trim or shift-select to extend or [Fence/Crossing/
Project/Edge/eRase/Undo]: prompt, pick the topmost portion of the ellipse above the
line. This trims the ellipse back to the line.
4.
Press ↵ to exit the Trim command.
In step 1 of the preceding exercise, the Trim command produces two messages in the prompt.
The first message, Select cutting edges..., tells you that you must first select objects to define
the edge to which you want to trim an object
. In step 3, you're again prompted to select objects, this
time to select the
object to trim
. Trim is one of a handful of AutoCAD commands that asks you to
select two sets of objects: The first set defines a boundary, and the second is the set of objects you
want to edit. The two sets of objects aren't mutually exclusive. You can, for example, select the
cutting-edge objects as objects to trim. The next exercise shows how this works.
First, you'll undo the trim you just did. Then, you'll use the Trim command again in a
slightly different way to finish the toilet:
1.
Press F-Z or type
U
↵ to undo the last action. The top of the ellipse reappears.
2.
Start the Trim tool again by clicking it in the Tool Sets palette.
3.
At the Select objects or <select all>: prompt, click the ellipse and the line cross-
ing through the ellipse. (See the first image in Figure 3.6.)
4.
Press ↵ to finish your selection.
5.
At the Select object to trim or shift-select to extend or [Fence/Crossing/
Project/Edge/eRase/Undo]: prompt, click the top portion of the ellipse, as you did in
the previous exercise. The ellipse trims back.
6.
Click a point near the left end of the trim line, outside the ellipse. The line trims back to
the ellipse.
7.
Click the other end of the line. The right side of the line trims back to meet the ellipse.
Your drawing should look like the second image in Figure 3.6.
8.
Press ↵ to exit the Trim command.
9.
Choose File
Save from the menu bar to save the file in its current state, but don't exit the
file. You may want to get in the habit of doing this every 20 minutes.
Here you saw how the ellipse and the line are both used as trim objects as well as the objects
to be trimmed. The Trim options you've seen so far—Fence, Crossing, Project, Edge, eRase, and
Undo—are described in the next section in this chapter. Also note that by holding down A in
step 4, you can change from trimming an object to extending an object.
