The Definition of Topology and Its Purpose in 3D Animation

As you learn to make 2D representations of 3D objects on the screen, think of 3D topology as the wireframe of an object. The wireframe, which is referred to in 3D software as the "mesh," is made up of hundreds or thousands of simple geometric shapes. The term "topology" refers to the geometric surface characteristics of the mesh. Each geometric surface on the mesh is a "face." The wireframe is the foundation of 3D modeling, which eventually results in three-dimensional digital animation.

A wireframe contains many polygons, vertices (the point at which three or more edges meet), edges that are lines made up of two vertices, arcs, curves, and circles, all of which form faces in the wireframe design. In computer-generated 3D topology, the goal is to have sufficient detail in the wireframe while keeping the number of faces to the minimum necessary to accomplish the job. In areas where the 3D model is destined to bend or move, the number of polygons is usually increased to allow for movement without distortion. Elsewhere, fewer polygons are needed. This is an important concept when modeling for 3D animation. The increased polygonal faces in areas of a 3D model that will undergo the most deformation during animation such as joints, facial features, and moving parts are important for realistic motion.

3D modelers strive for clean topology, typically illustrated by a 3D mesh with efficient polygon distribution, proper placement of edge loops, and clean, precise creases that minimize stretching and distortion.

Topology is a big topic, but beginning 3D modelers can benefit from a few tips:

• Use four-sided polygons freely, but avoid N-gons that have five or more sides.
• Use triangles sparingly unless the software you are using welcomes triangle meshes (some do).
• Avoid using elongated polygons. Your four-sided polygons should be relatively square.
• Keep it simple in the beginning. Model a square or a sphere. Then, move on to modeling a snowman, which is mostly spheres, a square, and a triangle. Don't start with an ambitious project until you are comfortable with your software.
• When you are ready, try some simple online 3D modeling tutorials.
• Even if you can afford the top-of-the-line 3D modeling software (lucky you), start out with one of the free 3D modeling programs for beginners.
• 3D modeling is difficult to learn. Be patient.

A surprising number of free 3D software programs are available. Any of these provide a good place for a beginning modeler to start.

• Daz Studio
• Hexagon
• Wings 3D
• Blender
• Sculptris

Most 3D modeling software sites provide tutorial videos to help beginners master the concepts behind 3D modeling. 

Professional-level 3D modeling programs can be intimidating and expensive. However, if you plan to be active in 3D animation — whether for creating video games, computer graphics, or films — you'll eventually end up needing to master one of them. Advanced-level 3D modeling software programs include:

• Autodesk Maya
• Modo by Foundry
• Adobe Fuse CC
• NewTek LightWave 3D
• Poser from SmithMicro
• Maxon Cinema 4D
• Autodesk 3ds Max Design