LT Unlimited

Create a Viewport with Holes

Now that AutoCAD LT has the ability to create non-rectangular viewports, I thought I'd share a way to create viewports with "holes", or empty spaces.
 
Let's say you want a triangular viewport with a circular hole in the middle.

The first step is to turn the objects into regions with the Region command, available on the Draw panel of the Home tab. Just start the command, and select the two objects. When you're finished, they don't look any different, but when you select them you'll see that the grips have changed, and if you try to grip-edit the shapes they'll move instead of stretch.

To get the hole in the middle, you'll use the Subtract command, to subtract the circular region from the triangular. This command is a little sneaky, since it's only available at the command line. (Of course, you could always put it on a button if you want.) You'll first pick the object to subtract from (the triangle), and then the object to be subtracted (the circle). Again, at first glance, nothing seems to have changed, but when you hover over the region boundary you'll see that it's now one object instead of two.

Now you're ready to turn the region into a viewport. To do this you'll use the "Create from Object" function from the Viewports panel of the View tab. This enables you to convert an existing object -- a closed polyline, an ellipse, a spline, a region (hint, hint), or a circle -- into a viewport. Just start the command, select the region, and there it is.

The region has become a viewport. You can pan, zoom, and set the scale just like you would with any other viewport. The only catch is that you can't edit the boundaries like you would with a polygonal viewport. To change it, you pretty much have to erase it and start over. (Sorry.) It can still be pretty handy, though!

Copy/Paste a Viewport

Today's post highlights one of those feature improvements that isn't big enough to get a lot of mention in the product documentation, but can still have an impact on your day-to-day productivity.

Prior to LT 2009, when you used Ctrl+C to copy a viewport and Ctrl+V to paste it, the new viewport was turned "off", i.e. it didn't display the objects inside it. You had to use the Properties palette (Misc --> On --> Yes) or the right-click menu (Display viewport objects --> Yes) to turn it back on.

Now, though, when you paste a viewport, it's turned on by default. (Hooray!)

I hope that saves somebody a few seconds in their day -- even a few seconds over hundreds of copy-pastes can add up to a lot of time!

Change Viewport Scale

A question came up on the discussion groups today, and I thought it would make a pretty good blog post.

Somebody wanted to know what happened in 2009 to the pull-down that you could use to change the scale of a viewport. It's still on the Viewports toolbar, if you want to turn that on, but at first glance it doesn't appear to be in the new Ribbon-based environment. (Another reason why second glances can sometimes be very helpful.)

It turns out that the viewport scale control is another context-sensitive bit of the user interface, like the mtext and Block Editor Ribbon tabs. When you have a viewport selected, or when you double-click inside it, a control appears on the right-hand side of the status bar.

In the image above, the viewport scale is 1" = 1'-0". If you look for this without having a viewport active, it won't be there, so pay attention!

Also, if you have Quick Properties turned on, one of the default listings for a viewport is its scale -- another quick and easy place to make the change.

Change Size of Quick View Previews

If the size of the Quick View Drawing or Layout previews are too big or too small to efficiently display the drawings you have open, it's really easy to change the size.

All you have to do is hover your cursor over one of the preview images, hold down Ctrl, and roll the mouse wheel up or down.

So the preview images go quickly from the default size...

To smaller previews...

Or larger.

Rotate View

I see a lot of questions out there (in fact, I got one by e-mail just last week) on how to rotate a view now that DVIEW is no longer available. Fortunately, it's still easy to do.

The two commands you'll need are UCS and PLAN. UCS stands for User Coordinate System, and is both a noun (i.e. "the current UCS") and a command name (i.e. "use the UCS command).

The most common scenario I see for this is that "north", which is typically "up" in model space, needs to point in a different direction on a sheet, usually to accommodate the shape of a building or site. In this case, "north" would correspond to the direction of the Y-axis in a 2D coordinate system.

So in order to rotate our view, we need to rotate the X and Y axes to a new direction. The easiest way to do this to rotate the UCS about the Z-axis. The Z-axis is perpendicular to both the X and Y axes, so in a 2D system like LT, that means it points straight out of the screen. (It's the same axis uses by the Rotate command, in case the previous sentence didn't help.)

Conveniently enough, there's a button on the UCS panel of the View tab of the Ribbon that will do exactly that. So if you want "north" to point right instead of up, click the "Z" button (or type UCS-->Z) and enter 90 (remember that positive rotations are counterclockwise). Now we have a rotated coordinate system.

Notice that the little square at the intersection of the axes has disappeared. That's becuase the current UCS no longer corresponds to the World UCS. But you'll also notice that your view hasn't changed. We've only changed the UCS, not the view.

That's where the PLAN command comes in. PLAN aligns the current view to a coordinate system, either the current one, the world one, or a previously-saved named one. It's available from the command line or through the Menu Browser, Tools menu, but not from the Ribbon.

Using it is simple. Just start the command and press enter to align the view to the current UCS. Notice that although the axes are back in their "normal" orientation, the square that indicates World UCS is still missing. This is a helpful visual cue to show you that you're in a different UCS.

If you've run this sequence in a viewport, I highly recommend locking it after you've finished panning and scaling your view. This just helps avoid any unexpected changes.

Also, if you need to continue working in the drawing, you'll probably want to set your UCS back to World (there's a big button on the Ribbon to do this) to put the axes back to normal.

Pan a Specified Distance

You can PAN specific distances with the View-->Pan-->Point command. (Or with "-P (note the dash) at the command line.) This command asks you to pick two points, the first of which must be selected with the mouse. Entering the second point at the command line (either in the "#,#" format or with polar or ortho tracking) moves the drawing by that amount. Selecting a second point with the mouse moves the view from the location of the first point to the location of the second point.

"Smooth" View Transitions

AutoCAD recently (in version 2006) changed the way it zooms, so that view changes that used to be instantaneous are now “smooth”. You can see an example of this if you zoom in to a small area of a drawing and then double-click the mouse wheel to zoom to extents.

Most people probably don’t mind one way or the other, but if you’d like it to go back to the old way, set VTENABLE to 0. (Setting it to 3 will restore the default behavior.)

Locking Viewports

Viewports have a property that allows them to be "locked", so they can't be re-scaled or panned. While this can be a little obnoxious on detail sheets (where things tend to change size a bit more), it's invaluable on plan sheets. Especially if you tend to double-click in viewport to make a small change, then zoom before you remember which space you're in. (It's happened to all of us.) Make your viewport, lock it, and you never have to worry about the scale again.

Switch between viewports

If you are in floating modelspace (i.e. inside a paperspace viewport), CTRL+R cycles through other viewports, making each active in turn. This is useful for activating a viewport that is completely contained inside another.

Panning Tips

Here's a bunch of tips on panning with the middle mouse button:

• You're not restricted to the drawing area while panning -- you can keep moving the view as long as you can physically move your mouse, even if the cursor reaches the edge of the screen.
• Holding CTRL will allow you to pan in any direction, as far as you want, until you release the middle button. The farther you move the mouse from its original position, the faster the view moves.
• Up to AutoCAD 2004, and in all versions of AutoCAD LT, holding SHIFT will constrain the panning to orthogonal directions.
• In AutoCAD 2007+, pressing SHIFT and then the middle button launches 3D orbit. However, if you hold down the button first, then press SHIFT, it will pan orthogonally as in previous versions.
• In AutoCAD 2007 and up, SHIFT+CTRL+middle button launches a 3D free orbit.