In order to use the methods in this book, you must understand the concepts, tools, and commands presented in this chapter. Any additional knowledge you have is a plus. However, don’t underestimate the usefulness of this chapter, even if you already consider yourself a SketchUp expert. It has plenty of tips, tricks, and helpful theories that will come up again later.
Five Core Concepts
Before you even open SketchUp, you need to understand the core concepts that make it unique. First, SketchUp is a surface modeler that is unlike most 3D modeling programs. Everything in SketchUp is composed of edges and surfaces, the basic building blocks used in SketchUp. A surface cannot exist without a closed loop of coplanar edges, and the simplest surface possible is a triangle (Figure 4-1).
Second, because it is a surface modeler, there are no true, perfect vector curves, arcs, or circles in SketchUp. However, you can still represent circles and curves with a series of small edges (Figure 4-2).