Understanding UV mapping

UV mapping is the process of applying textures to 3D models by unwrapping them into two-dimensional maps known as UV maps. To understand how UV mapping works, we need to visualize a simple example. Figure 7.1 illustrates how a cube can be unwrapped into a 2D map.

Figure 7.1 – A UV-unwrapped cube

A cube will typically produce a UV map shaped like the surface shown in Figure 7.2. As you can see, some of the cube’s edges were cut to allow for unwrapping, but some of the edges stayed connected. We will learn which edges to cut shortly.

Figure 7.2 – The UV map of a cube

When placed over an image texture, the UV map covers a certain area, as shown in Figure 7.3. This covered area is then projected on the surface of the 3D object, as we saw previously in Figure 7.1.

Figure 7.3 – A UV map placed over a texture

Similarly, a cylinder can be UV-unwrapped...