Chapter 21: Specifying 3D Coordinates

In This Chapter

Understanding 3D drawings

Working with 3D coordinates

Working with elevation and thickness

Creating a custom UCS for 3D drawings

The topics in the previous chapters have worked with X and Y axes. In this chapter, I add the Z axis. When you have a drawing with 3D objects, you can view it from any angle. The view that you've been using in 2D drawings is like looking at a house from the top, which you could call a plan view or a floor plan. From this view, even a 3D drawing looks two-dimensional. But when you look at a 3D drawing from an angle, you can see that there's more to it. Figure 21.1 shows the plan view of an office building on the left. On the right, you see the same drawing viewed in a perspective view from the front.