The key to working with AutoCAD successfully is understanding the way it interacts with you, This section will help you become familiar with some of the ways AutoCAD prompts you for input. Understanding the format of the messages in the Command window and recognizing of other events on the screen will help you learn the program more easily.
As the Command window aids you with messages. the cursor also gives you clues about what to do. It illustrates the various modes of the cursor and gives a brief description of the role of each mode, Take a moment to study this figure.
The Standard cursor tells you that AutoCAD is waiting for instructions. You can also edit objects using grips when you see this cursor. The Point Selection cursor appears whenever AutoCAD expect point input. It can also appear in conjunction with a rubber-banding line. You can either click a point or enter a coordinate through the keyboard. The Object Selection cursor tells you that you must select objects either by clicking them or by using any of the object selection options available, The Osnap marker appears along with the Point Selection cursor when you invoke an Osnap. Osnaps let you accurately select specific points on an object, such as endpoints or midpoints. The tracking vector appears when you use the Polar Tracking or Object Snap Tracking feature. Polar Tracking aids you in drawing orthogonal lines while Object Snap Tracking helps’ you align point in space relative to the geometry of existing objects. Object Snap Tracking works in conjunction with Osnap. You’ll learn more about the tracking vector.
Choosing Command Options
Many commands in AutoCAD offer several options, which are often presented to you in the Command window in the form of a prompt. This section uses the Arc command to illustrate the format of AutoCAD’s prompts.
Usually, in a floor-plan drawing in the U.S; an arc is drawn to indicate the direction of a door swing. It shows some of the other standard symbols used in architectural style drawings. This is a small sampling of the symbols available on the CD-ROM included with this book. See Appendix C for more information.
Next, you’ll draw the arc for the door you started in the previous exercise.
1_ Click the Arc tool in the Draw toolbar. The prompt Specify start point of arc or [C Enter]: appears, and the cursor changes to point selection mode.
Let’s examine this Specify start point of arc or [C Enter]: prompt. The start point contains two options. The default option is the one stated in the main part of the prompt. In this case, the default option is to specify the start point of the arc. If other options are available, they will appear within brackets.
In the Arc command, you see the word C Enter within brackets telling you that if you prefer, you can also start your arc by selecting a center point instead of a start point. If multiple options are available, they appear within the brackets and are separated by slashes (/). The default is the option AutoCAD assumes you intend to use unless you tell it otherwise.
2. Type CE↵ to select the Center option. The prompt Specify center point of arc: appears. Notice that you only had to type in the CE and not the entire word Center.
3. Now pick a point representing the center of the arc near the upper-left comer of the door. The prompt Specify start point of arc: appears.
4. Type @3<O.Metric users should type @9<O.The prompt Specify end point of arc or [Angle/chord Length]: appears.
5. Move the mouse and a temporary arc appears, originating from a point 3 units to the right of the center point you selected and rotating about that center, as in the top continued image. (Metric users will see the temporary arc originating 9 units to the right of the center point.)
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 are, picks the arc’s endpoint. Again, the cursor is in a point selection mode, telling you it is waiting for point input. To select this default option, you only need to pick a point on the screen indicating where you want the endpoint.
6. Move the cursor so that it points in a vertical direction from the center of the arc. You’ll see the Polar Tracking vector snap to a vertical position.
7. Click any location with the Polar Tracking vector in the vertical position. The arc is now fixed in place, as in the bottom continued image.
This exercise has given you some practice working with AutoCAD’s Command window prompts and entering keyboard commands skills you will need when you start to use some of the more advanced AutoCAD functions.
As you can see, AutoCAD has a distinct structure in its prompt messages. You first issue a command, which in turn offers options in the form of a prompt. Depending on the option you select, you gel another set of options or you are prompted to take some action, such as picking a point, selecting objects, or entering a,value.
the sequence is something like a tree. As you work through the exercises, you will become intimately familiar with this routine. Once
you understand the workings of the toolbars, the Command window prompts, and the dialog boxes, you can almost teach yourself the rest of the program !
Selecting Options from a Popup Menu
New you know that you can select command options by typing them in. You can also right-click at any time during a command to open a popup menu containing those same options. For example, in step 2 in the previous exercise, you typed C↵ to tell AutoCAD that you wanted to select the center of the arc. Instead of typing, you can also right-click the mouse to open a popup menu of options applicable to the Arc command at that time.
Notice that in addition to the options shown in the command prompt, the popup menu also shows you a few more options, namely Enter, Cancel, Pan, and Zoom. The Enter option is the ‘same as pressing ↵ Cancel cancels the current command. pan and Zoom allow you to make adjustments to your view as you are working through the current command.
As you work with AutoCAD, you’ll find that you can right-click at any time to get a list of options. This list is context sensitive, so you’ll only see options that pertain to the command or activity that is currently in progress. Also, when AutoCAD is expecting a point, an object selection, or a numeric value, you do not get a popup menu with a right-click. Instead, AutoCAD will treat a right-click as a ↵.
Be aware that the location of your cursor when you right-click determines the contents of the popup list. You’ve already seen that you can right-click a toolbar to get a list of other toolbars. A right-click in the Command window displays a list of operations you can apply to the command line, such as repeating one of the last five commands you’ve used, or copying the most recent history of command activity to the clip board.
A right-click in the drawing area when no command is active gives you a set of basic options for editing your file, like Cut,Paste, Undo, Repeat the last command, Pan, and Zoom, to name a few.
If you’re ever in doubt over what to do in AutoCAD, you can right-click any time to see a list of options. You’ll learn more about these options later in this book. For new, let’s move on to the topic of selecting objects.