Terminology!

This part of the site is more for you non-animators who have no idea of what I'm talking about when I discuss the more technical aspects of 3D animation... here are a few definitions and explanations that may help out...

DISCLAIMER: I don't always know what I'm talking about (in fact, I have been known to talk out of my arse) and I also intentionally lie, so don't quote me on any of the information within this page.

Short for Non Uniform Rational Bastard Splines. Nurbs are a kind of 3D surface. Basically they're bendy squares. It's as simple as that. They have their disadvantages and advantages...

Advantages: nurbs curvature is defined as a mathematical equation, so theoretically you can move as close as you want to nurbs surface and it will always be smooth. In practice, however, a nurbs surface tends to be tessellated before being rendered (though this depends on the renderer...).

But also they tend to deform a lot nicer (the reason I picked them for Dreg) seeing as when they bend, they actually are bending... I'm not sure even I know what I'm talking about...

Disadvantages: nurbs are a bitch to model with. Seeing as they are just squares, they don't approve of things like holes. This can seriously limit what kind of models you can make with them. You often have to resort to patches...

Also, nurbs tend to be more computationally expensive, and slow things down...

See also:

- polygons

- subdivs

- patches

POLYGONS:

Polygons, like nurbs, are a kind of 3D surface. Polygons aren't like nurbs. They're not bendy, and they prefer to be triangles. You can make them other shapes, but they will sneakilly get rendered as triangles posing as other shapes. They also have advantages and disadvantages...

Advantages: Dead easy to model with. And you can model them in any shape or form...

Disadvantages: Very hard to texture (you typically have to spend a month in a Tibetan temple sorting out the vertices onto a flat "uv texture map").

Polygons aren't curvy, so you need a dense polygon mesh to get the impression of smoothness. To properly skin a dense polygon mesh would be very slow, so you tend to skin a lower poly version of the model... but I find polygon deformations less pleasant than NURBS deformations...

See also:

- nurbs

- subdivs

- low poly

SUBDIVIDED SURFACES:

I don't really know much about subdivs, so I'll make something up.

Subdivs model like polygons, are smooth like nurbs, are a real bitch to texture, are computationally expensive, and one day might help solve world hunger. Also, some cultures believe that subdivs are a major aphrodisiac, as well as a cure for the common cold and soul rot.

See also:

- nurbs

- polygons

Low poly modeling is the process of modeling in polygons while doing the roly poly on the floor (the lower, the better). As a result, low poly models don't tend to be very detailed. This technique is often used for computer games (the code requires that you role about on the floor) and blocktests (it's fun).

See also:

- polygons

PATCHES:

One Patch is a nurbs surface. You often need several patches for certain kinds of models (for instance, Dreg's head...)

The problem arises when you want to deform the model; you want the patches to stay together. For this, you need to "stitch" the patches together (see why they call them patches now?). This tends to be computationally expensive and can slow things down a bit. It certainly does for Dreg's model anyway...

See also:

- nurbs

BLOCKTEST:

A blocktest is a very simple version of the final animation that helps you decide on the camera angles and timing of the film. The level of detail varies, but I think that for the blocktest to be really useful, it's worthwhile making it pretty detailed. I took my cue from the pre-viz tests from Lord of the Rings, which struck me as a really good way to work...

See also:

- my block test

RIGGING:

Rigging a character is very similar to rigging a ship, only without the ropes, sails, planks, stores, cannons, sailors, or anything else to do with ships. I hope that's cleared a few things up for you.

See also:

- skeletons

- skinning

- IK

SKELETONS:

You can create a skeleton for your character so as to decide how he/she/it deforms. It really works just like real life skeletons, with joints and tendons and cartilage and bone marrow. Well, not the tendons and cartilage and marrow but it's practically the same thing.

Skeletons have been a technique in computer animation for a long time, even during the early stages when they were trying to do computer animation in 2D. In fact, fossilized bones have been found in the prehistoric layers of certain operating systems, giving rise to theories of an entire kingdom of computer animation models that have been lost in the midst of time. Unfortunately, such occurrences are rare and very little is known of this former era.

See also:

- skinning

- IK

IK

IK stands for Inverse Kinematics. It's a process where you can control a series of bones by deciding where the final bone in the series ends up... a good example is an arm; I could position it by rotating first the upper arm, then the forearm (forward kinematics), or by deciding where the wrist will end up, and letting the computer figure out the rotations. As you can imagine, this often screws up and looks horrible, and you need to worry about things like pole vectors (something to do with hitting things with large, metal cylinders) and RPsolvers and SCsolvers (used for cleaning television screens).

See also

- skeletons

SKINNING:

Have you ever heard the phrase, "There's more than one way to skin a computer animation model"? Well this is where that saying comes from.

Skinning is the process of binding the character surface you have modelled to the skeleton you have made for him/her/it. This means that if you bend a joint in the skeleton, the surface should bend with it. Unfortunately, this very rarely works out and results in terrifying results that will haunt me to my grave. You can see what I mean in my making Dreg page...

There are different ways of editing skinning. One is "painting weights" where you can see all the parts of the surface which are being effected by a particular bone. Parts of the body which are fully effected will show up white, parts which aren't at all effected will be black, then there's all that grey area in between... You can edit this by painting this information directly onto the skin (thereby telling the surface which parts of it are effected by each bone...)

Another is to use influence objects... and there are other techniques, each as painful and difficult as the next...

See also:

- skeletons

- influence objects

INFLUENCE OBJECTS:

Influence objects are objects that you use to modify the skin of a character. Fundamentally they function just like bones, but aren't necessarily part of the skeleton hieararchy. They are often used to simulate muscle deformations and the like. They are used a lot in my model of Dreg...

See also:

- skinning

- skeletons

BLENDSHAPES:

Blendshapes help you mix lots of ingredients like eggs to make cakes. Only if you want you can use different facial expressions instead of eggs and what you'll get is a bunch of sliders to control your character's expressions - easy facial animation... or muscle animation... or clothing animation... or... muffins.

See also:

- rigging

PLAY BLAST

You know that saying "All work and no play blasting makes Jack screw up his timing"? Well here's the reason for that. A play blast is used when your scene is too complicated for you to play the animation within the application, so you "play blast" it, that is let the application take the time it needs over each frame, temporarily saving it into a film, which you can then view at real time to see how the animation is going. In fact, the blocktest (which you can view in the films section) is a play blast.

Adam Cubitt

Adam is my housemate and fellow member of this course. He likes to wear spandex and hurl rocks at squirrels. He comes from Luxembourg, a city of about 34 000 inhabitants that refuse to belong to any country. It is a cesspit of anarchy and sexual promiscuity- Adam's natural element. He speaks fluent Spanish but refuses to admit it to anyone. He will single-handedly revolutionise the computer game industry, but will probably kill himself doing it.

Miles:

Miles used to be a demonstrator on the course. He was a godlike being who lived on rock on a hill stroking his luscious, long beard. He would occasionally bless us with nuggets of valuable knowledge, and I think he sometimes played football.

Nowadays Miles farms chickens somewhere in the Caucuses.

Adam Vanner:

Adam is a lecturer on our course. He spends his time under an ancient, blessed tree seaking enlightenment and ignoring e-mails. He will impart knowledge if confronted, though, and his teachings proved invaluable to me when it came to modelling Dreg...