498 Part V: On a 3D Spree

To return to a single viewport later, simply click the plus (+) sign on the in-canvas viewport control.

The last thing to do is save the configuration you’ve just set up as a template (.dwt) file.

12.Click Save on the Quick Access Toolbar. From the Files Of Type dropdown menu, choose AutoCAD Drawing Template (*.dwt) and enter a filename. Click Save.

AutoCAD saves your new 3D template file in the same place as your other templates so it’s always there for you to select when you want to do some serious 3D modeling.

Seeing the world from new viewpoints

When you choose 3D in the Viewports dialog box’s Setup drop-down list, you direct AutoCAD to change the viewpoint in each viewport. The default viewpoints when you choose a four viewport arrangement are top, front, right, and SE (“southeast”) isometric. These viewpoints work well for viewing and constructing simple models, but eventually, you’ll probably want to specify your own custom viewpoint in a particular viewport.

In both AutoCAD and AutoCAD LT, the best — but not the easiest — way to change viewpoints is to use the drop-down list on the Views panel of the

View tab (shown in Figure 22-5) to switch to one of the standard orthographic 3D views or an isometric view:

The six standard orthographic (straight-on) views are Top, Bottom, Left, Right, Front, Back.

The four standard isometric views are SW (left-front), SE (right-front), NE (right-back), and NW (left-back). An isometric view is one in which you see the object from above, but not too high above — as though you were hovering in a low-flying helicopter.

The easiest — but not the best — way to change viewpoints is to click one of the named faces on the ViewCube (not available in AutoCAD LT). We don’t recommend this because the ViewCube is a viewing aid, and nothing but. You usually change to an orthographic view because you want to do some drawing or modeling there, and for that, your UCS (user coordinate system) ought to orient itself with the view. (See Chapter 21 for the skinny on UCSs.) Clicking Front on the ViewCube shows you a nice front view of your model, but it leaves the UCS unchanged, and that can make drawing anything difficult. Clicking Front on the View tab’s Views panel does change the UCS to Front so it matches the view and lets you draw without difficulty.

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Chapter 22: From Drawings to Models 499

Figure 22-5: The preset views drop-down menu.

These ten views are called “standard” because they’re often used in manual drafting and rendering work. They work well for showing 3D models of common objects such as mechanical components and buildings. You can also change to plan view, which is a top-down view of either the world coordinate system or a user coordinate system. (We describe coordinate systems in Chapter 21.)

The full version of AutoCAD has the ViewCube, the 3DORBIT command, and the Shift+middle button methods of changing 3D viewpoints (all are described in Chapter 21). AutoCAD LT’s options are much more limited. LT users can set nonstandard viewpoints by typing DDVPOINT and pressing Enter. In the Viewpoint Presets dialog box that appears, specify the following settings:

A viewing angle in the X, Y plane: Imagine moving a camera on a dolly around an object, while keeping the camera at the same elevation.

An angle from the X, Y plane: Imagine using a boom to swoop the camera up to a different height so that you’re looking at the object from increasingly steep angles.

AutoCAD users can set viewpoints the same way, but it’s grossly inefficient compared with the other viewing options.

By default, AutoCAD shows 3D models in 2D wireframe mode, even if you’ve created surface or solid objects. If you want to better visualize which objects are in front of which other objects, especially in an isometric or other nonorthogonal view, you have a couple of options:

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