As discussed in previous issues, a polygon model consists of vertices, edges, and faces, but there’s more. Hidden within the model are UVs and Vertex Colour Data, which we will discuss in future instalments. In addition, you have Surface Normals.
A model’s normals dictate how light will travel across its surface, effectively softening or hardening its appearance. Changing the angle of the normals can make a flat, polygon plane look almost rounded, and it’s because of this that you usually can’t see the individual polygons that make up a mesh, giving it the appearance of being more complicated than it is. Understanding this is essential whether you’re using the best 3D modelling software or learning on entry-level tools.
