IN THIS CHAPTER

Setting up paper space layouts

Looking into viewports

Examining details at other scales

Working in paper space

Most of this book revolves around setting up and using the model space environment that is an infinitely large (or at least 10⁹⁹ units across), three-dimensional realm in which you create your gleaming towers, tomorrow’s wondrous electronic gadgetry — or everyday garden sheds, angle brackets, and doorknobs. You may, however, have picked up a hint here and there that AutoCAD has a whole different parallel universe available to you, known as paper space.

The final product of all this setup, remember, is a printed drawing on a piece of paper. In most industries, paper drawings are legal contract documents, so they need to be easy to read and understand. In the first part of this documentation process, you configure the layout of the sheet in paper space, which I explain in this chapter. For the actual process of outputting either model space or paper space layouts to printer or plotter, see Chapter 16.

Chapter 2 introduces you to the two parallel universes of model space and paper space, and Chapter 4 explains how to configure model space for efficient drawing. This chapter explains how to set up layouts in paper space for efficient plotting.

Model space is the drawing environment that’s current when the Model tab (not the Model button on the status bar) is active. In model space, you create the “real” objects you’re drawing, so these objects are referred to as model geometry whether they’re 2D or 3D entities. When the Model tab is active, you see only objects in model space. Anything in paper space is invisible.

Imagine that your screen is displaying your drawing in model space. Now place a sheet of paper in front of your monitor and cut a square hole in it so you can look through it to see all or part of model space. This is like a one-way mirror; you can look through this paper space viewport to see model space, but model space can’t look back at you through the hole. You must have at least one paper space viewport in each layout to display anything in model space.

To see what I mean, try this:

1. Start a new, blank drawing.

   By default, it starts in model space.

2. Draw several random lines.

3. Click the Layout1 tab in the lower-left corner of the screen.

   AutoCAD switches to the default layout, which has one viewport into model space. All the lines you just drew fit into the central, rectangular viewport.

4. Draw a circle within the central, rectangular viewport.

5. Click the Model tab in the lower-left corner of the screen.

   Hey, where did the circle go?

6. While you're here, draw an ellipse within the general area of the lines.

7. Click the Layout1 tab.

   Like magic, the ellipse appears and the circle reappears.

That’s the basic principle of paper space layouts. Everything you draw in model space can be seen from paper space layouts, but nothing you draw in paper space layouts can be seen when you are in model space. This feature is particularly useful for drawing the borders and title blocks that you need when you plot a drawing but only get in the way in model space.

Figure 12-1 shows the arrangement of a default layout tab. It contains the following items:

• The white rectangular area represents a sheet of paper.
• The dotted rectangle shows the boundary of the actual area in which the current printer can print. Anything drawn outside this boundary (the margin) won’t print.
• The inner rectangle shows the viewport through to model space.

I turned on the grid when I did the screen capture to emphasize the fact that this is model space. As explained in Chapter 3, the grid can be turned on or off, and is never printed.

An AutoCAD drawing file always contains one and only one model space, but paper space can include more than one layout. For example, a complex drawing might have one layout for a general overview and several other layouts for larger-scale detail views. Each layout can then be plotted to its own sheet of paper. If the model space drawing is edited, all layouts automatically show the latest version.

Best practice these days is to draw the real stuff, such as the building, the machine, or the doorknob, in model space and the paper stuff, such as the border, the title block, the view labels, and general notes, in a paper space layout.

As I point out in a number of places in this book, the sacred mantra is “always draw everything full size.” The use of paper space layouts greatly simplifies this process. As discussed a little later in this chapter, you can define the scale factor for each viewport, as well as the size of the physical sheet of paper that your printer or plotter produces. Now you can simply plot every paper-space layout as full size and everything will fit.

In AutoCAD, you can ignore paper space layouts entirely and do all your drawing and plotting in model space. Originally, AutoCAD only had model space. Paper space wasn’t added to AutoCAD until 1990. But you owe it to yourself to give layouts a try. You’ll find that they make plotting more consistent and predictable and they give you more plotting flexibility. You’ll certainly encounter drawings that use paper space exclusively, so you should understand both systems.

Setting Up a Layout in Paper Space

Aside from arranging drawing sheets, layouts store plot information. AutoCAD can save several separate plot settings with each layout, as well as for model space, so that you can produce different types of plot for each one. For example, with one layout you can do quick check plots to a letter-size laser printer; with a second layout, you can do full-size final plots to a large-format plotter. In practice, you’ll probably use only one paper space layout tab most of the time, especially when you’re getting started with AutoCAD.

Put it on my tabs

The Autodesk documentation sometimes refers to the Model tab or to layout tabs, as I sometimes do. Out of the box, AutoCAD displays selectable tabs at the lower-left edge of the drawing window, clearly labeled Model, Layout1, and Layout2. Hovering your cursor over a tab pops up a preview of its contents. You can jump to a desired view just by clicking its preview image.

AutoCAD 2014 added file tabs at the top left of the graphic screen for each open drawing. Hovering the cursor over a file tab also produces quick views of model space and all layouts in the drawing. Figure 12-2 shows a typical arrangement in which AutoCAD has several drawings open. I added the orange rectangle to Figure 12-2 to emphasize the quick view. If you are hovering the cursor over the current file tab, a blue border indicates the currently active view. You can jump from view to view within a drawing or directly to a desired view in a different drawing just by clicking its preview image.

You can rename a layout tab (but not the Model tab) by double-clicking the layout name and typing a new one.

Any Old Viewport in a Layout

The viewports I talk about in this chapter are paper space viewports. You can also create viewports in model space, but they’re completely different animals. Model space viewports are also known as tiled viewports because (like bathroom tiles) they can’t have any spaces between them. You can use tiled viewports to look closely at widely separated areas of the screen or different viewports of a 3D model. I cover tiled model space viewports in Chapter 22 when I discuss 3D modeling. The potentially confusing aspect is that AutoCAD uses the same command name, and even the same dialog box, for creating the two different types of viewports. In this chapter, ensure that you’re in paper space when you create viewports.

Up and down the detail viewport scales

Paper space viewports are assigned drawing scales, and you can have multiple viewports, each with a different scale, all in the same layout. For example, one viewport can show the layout of a machine at 1:20, and another viewport can show an enlarged view of a small detail at 1:2. Because the individual viewports are scaled, the entire layout can be plotted at 1:1. Try the following steps:

1. On the Ribbon, click the Layout tab; then in the Layout Viewports panel, choose Rectangular.

   If the Rectangular button is grayed out (I know, they’re all rectangular — it’s the one that is labeled Rectangular), you’re still in model space. Switch to paper space.

   AutoCAD prompts you to pick the first corner of the new viewport.

2. Pick a point somewhere on the layout page to locate the first corner of the new viewport.

   AutoCAD prompts you to pick the second corner.

3. Pick another point to place the second corner of the new viewport.

   AutoCAD draws the viewport, and the model space geometry appears inside it.

   Unlike tiled model space viewports, paper space layouts can overlap each other or have spaces between them.

4. Zoom and pan until the new viewport shows the desired region of model space.

   If you zoom and pan in paper space, you simply zoom and pan the entire layout. If you zoom and pan in model space, it has no effect on the paper space viewport.

   Okay, here’s the clever part. While you’re in paper space, double-click inside the viewport. You have now reached through the hole in the time-space continuum and are working in model space. Any panning and zooming you do here does affect what’s visible in the layout viewport. When things are to your liking, return to the current layout by double-clicking anywhere in paper space outside the viewport.

5. Click the viewport boundary to which you want to apply a scale.

   The Viewport Scale button appears toward the right end of the status bar.

6. Find the scale that you want to apply to the active viewport, and then select it from the list.

   The display zooms in or out automatically to adjust to the chosen viewport scale.

7. Lock the viewport when the scale is correct.

   Click the padlock icon, which appears to the left of the Viewport Scale button near the left end of the status bar, to toggle viewport scale locking on or off.

Okay, here’s the warning I warned you about earlier in the chapter. If you don’t lock the viewport scale, someone (not you, of course) can mess up the viewport scale factor in all innocence, thinking he or she is just zooming in for a closer look.

You can zoom directly to an exact scale factor while reaching into model space through a viewport. Start the Zoom command, and then enter the desired scale factor immediately followed by the letters XP (“times paper,” not case sensitive). For example, Z 2XP will zoom in 2:1, and Z .5XP will zoom out 1:2. Now return to paper space and lock the viewport.

When a viewport is locked, you can still double-click in it to enter model space and create or edit objects that are visible in the viewport. Panning and zooming do not affect what appears in the viewport but do affect the entire layout, as though you had momentarily slipped back into paper space.

Viewport boundaries have most of the properties and capabilities of other drawing objects. You can still stretch, move, copy, delete, and so on, even when the viewport is locked. Grip editing, described in Chapter 11, can be particularly useful.

Earlier in this chapter, I say that viewport boundaries should normally be placed on their own non-plotting layer. That is generally true for the main viewport that shows all or most of the objects in model space. Standard practice, however, is for details at different scales to display their viewport boundaries, as shown in Figure 12-3. The solution is to create two layers for viewports, one that plots and one that doesn’t.

Practice Makes Perfect

Best practice when creating new drawings is to use paper space layouts with viewports. This greatly simplifies the drawing scale problem and related plotting issues. In particular, note the following:

• Model space
  • Always draw everything full size.
  • Use self-scaling notes (Chapter 13), dimensions (Chapter 14), crosshatching (Chapter 15), and non-continuous line types (Chapter 9).
• Paper space:
  • Everything “non-model” goes here, including the drawing border, the title block, and any generic notes.
  • Configure layouts with appropriate plotter, printer, and sheet size specifications.
  • Create appropriately scaled viewports.
  • Plot full size (1:1).

Clever Paper Space Tricks

The following list shows a few useful tips and tricks that will help you become a paper space guru:

• Create additional layouts as necessary. You can do this in several ways, including using the New button in the Layout tab of the Ribbon menu or simply clicking the + (plus) sign to the right of the rightmost layout tab.
• Delete unused layouts. Simply right-click the undesired layout tab, and then click Delete in the context menu that appears.

• Viewports don’t have to be rectangular. The Ribbon’s Layout tab includes three options in the Layout Viewports tab, but two will be hidden under the last one used. The options are Rectangular, Polygon (you pick a series of points that lasso the desired region), and Object, which lets you choose any existing closed shape and convert it to a viewport. That’s how I created the elliptical detail in Figure 12-3.

• Freeze layers in individual viewports. You don’t always want to show everything in every viewport. If you enter model space by double-clicking inside a viewport, the Layer Properties Manager (see Chapter 9) lets you freeze selected layers in the current viewport. Conversely, the drop-down list below the Layers panel of the Home tab includes a command to freeze the layer of the selected object in all other viewports except the current one.
• Snap into model space. Even when you are in paper space, it’s still possible to snap onto objects in model space that are visible in a viewport. This technique was used mostly before self-scaling annotations came along. Dimensions could be applied from paper space without having to worry about scaling them. The problem is that it’s usually more helpful to have the dimensions in model space when you are working there.

• Use templates. Ah, now here’s the biggie. I refer to template files in several chapters, but a quick refresher wouldn’t hurt. A template file serves as the starting point for a new drawing and can contain anything that a normal drawing file can contain. This includes everything discussed in this chapter: layouts, viewports, plotting configurations, borders, title blocks, and so on. John Walker, one of the founders of Autodesk, is rumored to have once said that an AutoCAD user should never have to do anything twice. I don’t think he said it again.

  But wait! There’s more! A bit of exploring will reveal that the commands for creating and configuring layouts and viewports all have a From Template option. You can browse through the current drawing and through any existing drawing or template file anywhere to inhale the complete layout setup specifications. Complete means everything; for example, if you are setting up a layout from a template and the source includes viewports, a border, and a title block, it all comes over to the new layout, including the creation of any new layer, text, and dimension specifications and block definitions required.

  If the current drawing contains any specifications with the same names as the source, the host drawing wins and the incoming specifications are ignored. The existing specifications will be applied to the incoming objects.