What Is Computer Animation?

What is computer animation, in one paragraph?

Computer animation is any moving image a computer generated rather than recorded. A camera captures light that already existed. An animator on paper draws each frame by hand. In computer animation the frames are calculated: you describe what exists, how it moves and how it is lit, and software produces the pictures.

That description covers two quite different crafts. 2D computer animation moves and deforms flat artwork in a plane, so a new viewing angle means new artwork. 3D computer animation builds objects in a virtual space that has depth, assigns them materials, lights the scene and points a virtual camera at it, so a new angle is a camera move. Every practical difference between the two comes out of that one distinction, and it is unpacked properly in 2D vs 3D animation.

Encyclopedias will tell you this much and then stop. The rest of this page is the part a lexicon does not have: what the process looks like when someone is paying for it.

How does computer animation actually get made?

Not by pressing animate. The pipeline is a sequence of stages, and the reason it is a sequence is money: each stage bakes in the decisions of the one before it, so a note that arrives late costs far more than the same note arriving early.

Stage	What happens	What a late change here costs
Concept and previz	A rough animatic with camera, timing and staging	Almost nothing, which is the point of doing it
Modelling or artwork	Geometry is built, or CAD is cleaned up, or artwork is drawn	Moderate, but it invalidates everything downstream
Rigging	Controls are built so a model can be posed and moved	High, because animation sits on top of it
Look development	Materials, surfaces, lighting, tested on still frames	Moderate, and it is where realism is actually won
Animation	Movement, timing, weight, camera	Moderate, creative hours
Simulation	Cloth, fluid, particles, destruction are computed	High, everything has to be recomputed
Rendering	The machine calculates the final images	Machine time, not creative time
Compositing and grade	Layers are assembled, colour is set, elements are added	Low, this is where changes are cheapest again

The shape of that table is the single most useful thing to know before commissioning anything. Feedback is cheap at the top, expensive in the middle, cheap again at the bottom. Almost every troubled animation project is a project where notes about the middle arrived at the end.

What are the different types of computer animation?

Type	How the motion is created	Typically used for
2D frame and vector animation	Artwork is drawn or deformed over time	Explainers, illustrated brand films, titles
Motion graphics	Type, shapes and layout animated in a plane	Broadcast packaging, UI, information layers
3D keyframe animation	Objects and cameras posed at key points, interpolated between	Product films, characters, commercials
Motion capture	A performance is recorded and mapped onto a digital character	Games, feature film characters, realistic human motion
Procedural and simulation	Rules and physics compute the motion: cloth, fluid, particles, destruction, growth	FX shots, material behaviour, anything too complex to hand animate
Real time and game engine	Frames are generated as they are viewed, not pre-rendered	Games, live stage visuals, interactive configurators

Finished work is rarely one row. The adidas ZK 2K Boost films are 3D keyframe animation carried by physics driven motion. The Trainline Tap That App hands are hyperreal 3D character work with simulation on top and 2D graphic layers composited over. Categories are a way of talking about the work, not a way of scoping it.

Why is 3D computer animation used for advertising?

Because advertising needs the same idea in many versions, and because the objects in it frequently do not exist yet.

A product can be animated from CAD months before the first physical sample. A colourway that has not been manufactured can be shown. A shot that would be unsafe, impossible or absurdly expensive to film costs the same as any other shot. And once the scene exists, a vertical cut, a square cut, a fifteen second edit and a set of print stills all come out of the same build rather than out of a second shoot.

That last point is the commercial argument, and it is why almost every product film you scroll past is computer animation now. The decision against a shoot is compared directly in CGI vs live action product commercials.

Where else is computer animation used?

• Film and television, both for creatures and environments and for the invisible work that nobody registers as animation.
• Games, where animation has to run in real time and respond to a player rather than play back.
• Music videos and artist work, where the freedom to break physics is the reason for choosing it. My music video collection covers releases through Universal Music, Sony Music and Gorillaz.
• Product design and engineering, where the same model that will be manufactured gets reviewed and presented in motion.
• Science, medicine and materials, showing behaviour that cannot be filmed at all. BASF Design Fabrics is that case: simulating how materials behave rather than photographing how they look.
• Live shows and stage screens, which is mixed reality production.
• Interfaces, every transition and micro-animation on the device you are reading this on.

Does computer animation have to look photoreal?

No, and treating photorealism as the quality bar is the most expensive misunderstanding in the field.

Photorealism is a target like any other. Chasing it means accurate materials, accurate light, subtle imperfection and far more render time, and it is worth paying for when the viewer has to believe a real object exists, as with a product close-up or the hyperreal hands in the Trainline work. The same technique also produces deliberately stylised imagery: Starfish and Coffee is 3D throughout and reads as illustration by choice.

The useful question is not how real it should look, it is how real it needs to be for the viewer to accept it. Those are different numbers, and the gap between them is often the largest single cost driver in a project. The rest of the drivers are in what drives the cost of a CGI commercial.

What software do computer animators use?

3D work happens in Houdini, Blender, Cinema 4D or Maya, with a renderer such as Redshift, Cycles or Arnold attached. 2D work happens in After Effects, Toon Boom, Moho or Animate. Compositing, where every layer is finally assembled, happens in Nuke or After Effects. Game and real time work happens in Unreal or Unity.

I work in Houdini with Redshift and composite in Nuke. The reason is procedural: in Houdini a scene is a network of operations rather than a stack of manual edits, so a changed input recomputes the result instead of forcing a rebuild. That is worth very little on a single static shot and worth a great deal on a campaign where the product spec is still moving. The full argument, including where Blender is the better answer, is in Houdini vs Blender for commercial VFX.

Software is the least interesting variable, though. No tool makes a shot read correctly. Timing, weight, staging and light do, and those transfer between every package on that list.

Is computer animation a good career?

It is a real one, with an honest caveat. The craft rewards people who like solving problems as much as making pictures, because most days in 3D are technical: geometry that will not behave, a simulation that will not settle, a render that is too slow. The people who last are the ones who find that part interesting rather than the ones who only enjoy the finished frame.

The other honest note is that the field keeps splitting into specialisms. Generalists exist, particularly in advertising where projects are small enough for one person to carry, but most studio roles are narrow: modelling, rigging, lighting, FX, compositing. Deciding which of those you actually enjoy matters more than which software you learn first.

How do you commission computer animation?

Answer three questions and the technique mostly picks itself.

1. Is the thing on screen a physical object or an idea? Object points to 3D, idea points to 2D or motion graphics.
2. How many versions do you need, counting formats, lengths and languages? One points to 2D, several points to 3D.
3. How stable is the brief after sign off? If the product or the copy is still moving, a procedural 3D setup absorbs that better than redrawn artwork.

Then write the brief around what the film has to do rather than around how it should be made. The full range of what that turns into is on 3D animation services, and if you already know you need a person rather than a process, hiring a freelance 3D artist covers what I need from you to start.

Got a project? Describe it in a few lines with the goal, the formats and whether a physical product is involved, and you will get a straight answer back, including when the answer is that animation is not what you need.

Written by Marco Mori, 3D artist and creative director in Lindau at Lake Constance, Germany, working with brands and agencies worldwide.