3D animation: definition, stages, the 3D animator's job and training

Animated films, series, adverts, video games, product visualisations: 3D animation is everywhere. Behind every shot, a chain of jobs and stages turns an idea into images. This guide explains what 3D animation is, how a film is made, what a 3D animator does and how to train, starting from the essentials.

What is 3D animation?

In 2D animation, every frame is drawn. In 3D animation, the characters and sets are built once in a three-dimensional space, then moved over time. The camera is virtual, and so are the lights, and software calculates each final frame. The advantage: the same character can be filmed from every angle, and a change carries through the whole film. The trade-off: every frame has to be calculated, sometimes for a very long time.

The first feature-length animated film made entirely with computer-generated imagery is Toy Story, released in 1995. Since then, 3D has become the dominant technique in animated cinema, and it has spread to series, video games and advertising.

The stages of a 3D animation production

1. Writing and storyboard: the story is broken down into drawn shots, then edited with a temporary soundtrack (animatic) to approve the pacing.
2. Modelling: characters, sets and props are created in 3D. The 3D modelling guide presents the methods.
3. Textures and materials: the colour, roughness and relief of each surface.
4. Rigging: each character gets a skeleton and controls, as explained in the Blender rigging guide.
5. Layout: placing the cameras and setting up each shot.
6. Animation: the animators set the keyframes and refine the movement.
7. Effects: simulations of fluids, smoke, cloth and hair.
8. Lighting and rendering: the lights are set, then each frame is calculated.
9. Compositing: the rendered layers are assembled, graded and finished.

In a studio, each stage has its own specialists. A freelancer or a small team often chains them together in a single application, which Blender makes possible.

Animation techniques

• Keyframe animation: the animator sets the important poses, the software calculates the in-between frames, and the animator refines the curves. It is the basis of character animation. The Blender animation guide puts it into practice step by step.
• Motion capture: an actor's movements are recorded, then applied to the character's skeleton before being reworked.
• Simulation: physics calculates the movement of fluids, cloth and destruction.
• Procedural animation: rules generate the movement, such as a crowd or a field of grass in the wind.

The classic principles of animation apply in 3D as they do in 2D: timing, anticipation, squash and stretch, arcs, exaggeration. The walk cycle guide and the smear frames guide show two applications.

The 3D animator's job

The 3D animator brings characters and objects to life: they act out the scene through them, setting the weight, the rhythm and the expression. They work from the storyboard and from video references, often filming themselves. Around them are other 3D jobs: modeller, rigger, texture artist, visual effects artist, lighter, compositor, and the generalist who does a bit of everything in small companies.

The openings are in feature film and series studios, video games, advertising, architectural and product visualisation, and motion design. Many animators work freelance, from one project to the next.

Training in 3D animation

Several paths lead to the job:

• Specialised schools, public or private, offer courses lasting several years, often with admission based on a portfolio and an entrance exam. Compare the students' graduation films, which show the real level reached, as well as the admission and funding conditions.
• University and vocational courses in digital arts and computer graphics.
• Teaching yourself, with free resources: the guide to learning Blender offers a path in seven steps.

Whatever the path, what counts when you are hired is the showreel: a minute or two of your best shots, from the strongest to the weakest. Three short, perfectly animated shots are better than one long, uneven film.

3D animation software

Large studios often use Maya for character animation, Houdini for effects, and dedicated render engines. Blender, free and open source, covers the whole pipeline and has established itself among freelancers, small studios and in education. For learning, it has the advantage of bringing everything together: modelling, rigging, animation, simulation, rendering and compositing.

Rendering: the stage that takes time

One second of animation has 24 or 25 frames, often more. If each frame takes two minutes to render, one minute of film already represents nearly two days on a single machine. That is why studios split rendering across many machines, and why freelancers turn to a render farm. To estimate the duration of an animation before starting it, the render time calculator works from the time of one frame.