LT Unlimited

Rectangle by Area

Today I'll conclude my 3-post series on drawing rectangles in AutoCAD LT. (Who'd have thought there could be so much to say about rectangles?)

By now you know that you can define the second corner of a rectangle (after you pick the first corner) by specifying a rotation or dimensions. The option that's left is specifying an area.

This time, you start the RECTANG command, pick your first point, and enter A for Area.

Specify other corner point or [Area/Dimensions/Rotation]: A

The next prompt is for total area. Remember to use the current units, i.e. square inches for architectural drawings.

Enter area of rectangle in current units <100.0>: <enter number>

Then you're asked for either the length (aka X direction) or the width (Y direction), to be used in calculating dimensions.

Calculate rectangle dimensions based on [Length/Width] <Length>:

Enter rectangle length <10.0000>: <enter number>

The sign of the number you enter determines which side of the cursor your rectangle ends up on. Positive numbers create rectangles above and to the right (positive X and Y), and negative numbers create rectangles below and to the left (negative X and Y).

You may notice that this finishes the command. So if you want to use the Rotation option too, you'll need to set it first.

Rectangle by Dimensions

In my last post, I showed you how to create a rectangle with a pre-defined rotation. Today, we'll continue working backwards through the Rectangle options and talk about creating a rectangle by defining its dimensions.

Let's say you start the RECTANG command and pick your first point. But instead of picking the other corner right away, you enter D for Dimensions.

Specify other corner point or [Area/Dimensions/Rotation]: D

In that case, you're prompted for length and width numbers.

Specify length for rectangles <10.0000>: (enter a number)

Specify width for rectangles <5.0000>: (enter a number)

Finally, you're prompted for the "other corner point". But because you've already entered the rectangle's size, the only thing left to pick is the orientation. The numbers you entered for length and width were actually absolute values, so you have to pick the quadrant for the rectangle, e.g. positive X, positive Y or negative X, positive Y, and so on.

Try it, and you'll see the rectangle flip about the X and Y axes as you move your mouse around.

If you want to combine the Dimensions and Rotation options, you must remember to enter the Rotation angle first. Otherwise, you'll just end up setting the dimensions again afterwards.

Next up, the Area option.

Rectangle by Rotation

Most of the time, a rectangle's sides are simply horizontal and vertical. (At least, most of my rectangles look that way.)

But sometimes, they're not.

To get a rectangle that looks like this, you have two options. (It's not AutoCAD LT if you don't have options, right?)

Of course, you could just draw the rectangle and then rotate it. But that's two commands. Why use two when you can use just one?

So instead, you can use the Rotation option of the Rectangle command to set the angle and the size at the same time.

After you pick your first point, you can see at the command line that you can either pick a second point, OR use the Area, Dimensions, or Rotation options.

Specify other corner point or [Area/Dimensions/Rotation]:

Enter R for Rotation, and you're able to define a rotation angle, either by typing it in or picking points. The only downside is that you don't get the "rubber band" effect that you usually see, so I'd save this method for when you either know your angle or have another object to snap to.

After you set your angle, you can either pick the other corner point or define the rectangle by its Area or Dimensions. (We'll come back to those options in a future post.)

There are two things to keep in mind when using this method of rotating rectangles.

First, if you choose to type in a coordinate pair for your rectangle size, it will use the current coordinate system to set the corner point, not the size of the rectangle. In other words, if you set your rotation angle to 30 degrees, then type 10,5 this is what you'll get:

Which may or may not be your intended result.

Second, the Rotation angle setting is "sticky." So the next time you use the Rectangle command, you'll have to reset the angle if you want a different rotation (like 0).

Breaklines

I got an e-mail last week asking me about creating break lines in AutoCAD LT. You know, for when you want to show only part of an object and indicate that it continues.

There's no built-in way to do this in AutoCAD LT (AutoCAD has an Express Tool), but it's not hard to make your own.

Here's the dynamic block I built to replace the Express Tool:

Its insertion point is in the center, and it has an independent stretch action for each end. (I use the M2P object snap a lot when placing this breakline. I also threw in a rotation action, but as it acts on the whole block, it's optional. (Without the rotate action, you can accomplish the same thing with grip-rotating or the Rotate command.)

I put the block on a tool palette, and set up its auxiliary scale so that it would insert at the current dimension size. It's worked great ever since.

In the spirit of "teaching to fish", I'm not going to post the block here. It's pretty simple to make -- with just a little knowledge of dynamic blocks you'll be able to create it yourself. But maybe I'll use the rest of this week to walk through the steps...we'll see what other tips I come up with between now and then. :-)

Exploring the Units Dialog

You can use the Units dialog choose the display and input format of length and angle measurements. The command location has moved around a bit in recent years: In LT 2010, it's under the Application Menu-->Drawing Utilities-->Units; in LT 2009, it's on the Tools tab, Drawing Utilities panel; in previous versions look under Format-->Units; and in all versions you can type UNITS.

For length, you have the following options. The numbers in parentheses show how a sample length -- 41.5 units -- would be displayed with each type.

• Architectural (3'-5 1/2")
• Decimal (41.5)
• Engineering (3'-5.5")
• Fractional (41 1/2)
• Scientific (4.15E+01)

You can choose the precision you want to display, from low to high -- this doesn't affect input, just how many decimal places or fraction denominators you'll see when you list something or use a measuring command.

You can also choose the format of your angles. The numbers in parentheses show a sample angle -- 30.5 -- would be displayed for each type.

• Decimal Degrees (30.5)
• Degrees/Minutes/Seconds (30d30'0")
• Grads (33.889g)
• Radians (0.5323r)
• Surveyor's Units (N 59d30'0" E)

You can set the display precision for angles too, and choose to have them go clockwise instead of counterclockwise.

For any of these linear or angular formats, you can only use special characters that correspond to the current type. For instance, entering 4'6 when your type is set to Decimal or 45d10 when your type is set to Grads won't work. But decimal entry always works.

The Insertion Scale option has to do with copying content between files that have different units. It's related to other settings in the Options dialog, so I think I'll say more on that another day.

Finally, down at the bottom, is the Direction Control dialog.

This enables you to set the "zero" angle for your file -- to the right (East), up (North), left (West), down (South), or any direction you choose. (East is the default -- it corresponds to most standard coordinate systems.)

Wipeout!

So I promised you in my last post that I wouldn't get carried away talking about all the fun new stuff in AutoCAD LT 2010, and I'm sticking to that. In fact, today's topic has been around since at least AutoCAD LT 2006. (That's the oldest version I have access to right now. If someone with an earlier version has other information on when it showed up, please let me know.)

Wipeouts do just what you would think -- "wipe out" part of your drawing -- although it's not quite as devastating (or permanent) as it sounds.

A wipeout is simply an object that can cover other objects with a blank area, either to make text more legible or to cover up unwanted portions of a drawing. It doesn't erase anything, just covers it up. You can control exactly what is covered with the Draw Order command.

For example, let's say I needed to cover up part of this line of shrubs/bushes.

I'll start the Wipeout command (either from the ribbon, the Draw menu, or the command line) and choose enough points to define the shape I need. A wipeout is always closed -- the command always draws the last side of the polyline for you. I could also use the Polyline option of the command to choose an existing closed polyline to convert to a wipeout.

The wipeout is automatically created so that it covers up all my existing objects.

If I don't want that, I can use the Draw Order command to bring some of the objects on top of the wipeout.

Finally, if I don't want the frame of the wipeout to print, I can use the Frames option of the wipeout command to turn them all off. This option has two limitiations: You can't select a wipeout if its frame is off, and you can't turn off specific frames individually. It's all or nothing.

Drafting Settings Part 5 -- Quick Properties

All right, we've reached the last tab in the Drafting Settings dialog! Welcome to Quick Properties.

In case you haven't seen Quick Properties palette yet, it's a miniaturized version of the full Properties palette that pops up when you select an object in your drawing. It looks something like this:

Of course, you can customize this palette to best suit the way you work. If you couldn't change some settings, we wouldn't be talking about it, would we? So here are the Quick Properties settings:

Like every other tab we've seen, this one has an on/off checkbox right at the top. Right below it, though, is an interesting setting specifying precisely when it comes on. You can choose to have Quick Properties displayed for every object, or only for "defined" objects. A "defined" object is one that has some of its object-specific properties chosen for use as quick properties. Object types that are not "defined" would show only color, layer, and linetype.

Where you do you define these objects? Take a look back at the shot of the Quick Properties palette, and look for the icon in the upper-right corner, next to the object type name. That's the Customize button, and it takes you directly to the part of the CUI editor where you can select which objects have Quick Properties at all, and what those properties are. It looks like this:

 

So here, a selected circle will display its radius and area, but not its diameter, in the Quick Properties palette. To add one more level of customization to this, you can choose which object types appear in the left-hand list using the button at the top of the image above. You can probably identify which properties are most important to you in a short swing through this dialog.

Under "Location Modes", you can choose where on your screen you want the palette to appear. "Float" means that it will appear in the same place every time, just like a regular palette. "Cursor" means that it will pop up next to your crosshairs, whereever they are on the screen. If you choose Cursor, you can also further specify the position by quadrant (top-right, top-left, bottom-right, bottom-left) and by the distance (in pixels) that the palette will stay away from the cursor.

Finally, you can control the size of the palette with the Auto-Collapse option. If you turn on Auto-Collapse, you only see a few rows of the palette -- you can choose how many -- until you hover your cursor over it. If Auto-Collapse is off, you see all available quick properties immediately. If you are more likely to use Quick Properties to view object information, you might find Auto-Collapse helpful, but if you are more likely to use it to make changes to object properties, you may find that Auto-Collapse is more cumbersome (because you have to wait for it to unroll before you can make your changes). In the end, it's up to you.

Well, I think that's the end of what I have to say about the Drafting Settings dialog. Thanks for hanging in for the full tour. I hope you learned a few new things (I did!), and that you'll be able to use a few of them to be more productive.

Drafting Settings Part 4B -- Dynamic Input, Cont.

Last time on LT Unlimited, I continued the tour of the Drafting Settings dialog with the first half of the Dynamic Input settings. And now, the conclusion. (Of Part 4, that is. There's still Part 5.)

I'll pick up again with the "Settings" button for Pointer Input.

There are two pairs of options regarding the format of input for "second or next points", such as when you begin the Move command, pick your first point, and are asked for the second. You can choose between Polar (distance,angle) or Cartesian (x,y) input. The default is Polar, but personally, I'm more likely to know the X and Y values of my distance rather than the distance and angle, so I switched it. Your method may vary. You can also choose here whether you want AutoCAD LT to assume the numbers you're giving it are relative coordinate, or absolute. It defaults to relative, so if you want to move something to (0,0) or another actual coordinate point, you need to preface the input with the pound sign (#). Now you see why you don't have to type @ any more to force relative coordinates!

The second category is about when the input tooltip is visible. The default is that it will show up whenever you're asked for a point, but you can also choose to delay its appearance until you start typing, or force it to display all the time.

The final dialog in the Dynamic Input tab is the Settings dialog for Dimension Input.

Here, you can choose how many input fields you want to see at a time. There are five possible input fields: Resulting Dimension, Length Change, Absolute Angle, Angle Change, and Arc Radius. The default is to see 2 fields at once, but you can also show only one, or any combination of the five.

No matter which visibility setting you choose, you can cycle through all available fields by pressing TAB. Remember than not every field applies in every command or for every object. For example, Arc Radius doesn't apply to lines.

All right, that's it for Dynamic Input! Next up, last but not least...Quick Properties.

Drafting Settings Part 4A -- Dynamic Input

I realized, looking at the Dynamic Input tab of the Drafting Settings dialog box, that it's the most complicated of all the tabs. Not because the topic itself is particularly confusing, but because there are three sub-dialogs in addition to the main window. So this tab will be split up over two posts, in order to minimize information overload.

Dynamic Input was introduced in AutoCAD LT 2006 as a way of moving important command information up into the drawing area, so that you don't have to look down at the command line all the time. It puts floating boxes with command options, prompts, and coordinate information right next to the cursor where it's easily seen.

The main Dynamic Input tab has three areas:

Everything in this main tab has to do with turning Dynamic Input features on or off. First, in the upper left-hand corner, is "Enable Pointer Input". When it's on, you get boxes next to the cursor where you can type in coordinate values.

Next is "Enable Dimension Input". When this is on, and you're creating or grip-editing geometry, the boxes you get are for geometric properties of the object, like length or angle. Dimension Input isn't always available for every command, though, which is why it's often used in combination with Pointer Input.

Both of these options have their own dialog of special settings, but I'll save the details for the next post. (See, now you have to keep reading!)

Last up is "Command prompting and command input". This turns on the tooltips for command-specific prompts and options, such as "Specify next point." When this is on, you can also use the down arrow to see all the available command options on the screen, instead of at the command line. Note: You must have either Pointer Input or Dynamic Input (or both) turned on in order to see the command prompts. It doesn't work all by itself.

The one extra settings dialog I will get into today is the Drafting Tooltip Appearance dialog.

At the top, you can see a preview of what your tooltips will look like -- this applies to all the prompts (Pointer, Dimension, and Command). The "Colors" button launches the same Drawing Window dialog that you can get from the Options dialog, just with the tooltip settings already highlighted. There, you can pick whatever colors you like best for the text and background of the tooltip.

Next are two sliders for size and transparency. The default for both is 0, which means a normal size and an opaque background.

The last setting here asks whether you want all your tooltips to look the same, or whether you want some of them to take their properties from your Windows settings. If you choose "use settings only for Dynamic Input", then your Polar and Object Snap Tracking tooltips will take their colors based on other Windows tooltips, instead of the colors you've set yourself. Like all the settings we've talked about, this is purely a matter of personal preference.

See you next time for more on the options for Pointer and Dimension Input!

Drafting Settings Part 3 -- Object Snaps

Part 3 in our tour of the Drafting Settings dialog box is all about Object Snaps, or "osnaps" for short.

Just like the other two tabs we've seen already, the Object Snap tab has on/off toggles at the top for both the snaps themselves and tracking.

Object Snaps enable you to precisely grab a point on an object, such as an endpoint of a line or the center of a circle, to make sure that geometry that you create or modify ends up exactly where you want it to be. Nothing's more frustrating than receiving a drawing, opening it up, and realizing it that whoever created it didn't use any object snaps. It can mean that "intersecting" lines don't actually touch, or that lines that are supposed to be precisely 6" apart are some fractional amount off from that. That can create some real headaches. (If you've ever seen a drawing like this, you'll know what I'm talking about. If not, be grateful.)

Osnaps can be activated as a one-time snap, or set to be on all the time. The checkboxes in this tab are for the "all the time" osnaps, or running osnaps. The screenshot above shows my personal preference for running osnaps. One osnap that I never set as running is Nearest. There are times when it's an appropriate snap to use, but mostly I'm concerned that instead of grabbing an endpoint or midpoint as I want, I'd end up with a "nearest" point instead. I'm not trying to say that Nearest should never be used as a running osnap, just...be careful.

If you only need a particular object snap once in a while, there are two ways you can get it without turning it on permanently. First, you can type its command line shortcut, usually the first three letters of the snap name (END, MID, CEN, etc.). Or you can hold down SHIFT and right-click, and pick your osnap from the shortcut menu that pops up.

The icon next to each osnap name is the shape you will see when that particular snap is active. The example below shows the endpoint and midpoint icons. To cycle between nearby locations for running osnaps, press the TAB key until you see the icon you want.

Now, when you hover over an osnap location long enough for its tooltip to appear (as I did in the above image), something special happens. That point has now been "acquired", and you can track from it to find another point in the drawing aligned with that one. It's called Object Snap Tracking (or otrack for short), and it's very similar to Polar Tracking -- see Part 2 for more on tracking angles.

To see how this works, imagine that you wanted to draw a line that started at the center of a rectangle. Instead of drawing a construction line from corner to corner, snapping to its midpoint, drawing the line, and then erasing the construction line, let's use Object Snap Tracking instead.

First, I'll hover over the middle of one side of the rectangle until the midpoint icon appears. Then I'll move the cursor up until a dotted line appears, telling me that otrack is active.

Next, I have to go get the other side. Notice that there's still a small "+" at the location of the first midpoint, identifying it as a tracking point.

Finally, when I move my mouse close to the intersection of these two dotted lines, they BOTH appear. I can then left-click to begin drawing my line.

That may seem like a complicated explanation, but I promise you it takes 10 times longer to explain it than it does to use it.

Well, that's enough about Object Snaps and Object Snap Tracking for today. Next up: Dynamic Input!