Starting out with 3D #1 (A - E)

With each technological advancement a few new words are invented. For example a Hard drive, an Operating System, Application software, PDF, etc.  All those were words that you wouldn’t find anywhere a hundred years ago. 3D is no exception. There are hundreds of new words and terms you should learn before you can think of going into 3D.

First off, you should know that 3D is a space that has height, width and depth. 2D only has height and width.

Note: Not only should you know 3D terms before you can tackle 3D, make sure you know your 2D terms to! Such as channel, animation, co-ordinate system etc.

Due to the massive amount of words that was invented for 3D, this topic was split into several parts, I also only included the important ones, things you will be using a lot, or things I think will be much more popular in the future. At the end of the series, you can find a downloadable PDF file with all the words neatly summed up.

#1 (A – E)
#2 (F – L)
#3 (M – P)
#4 (Q – T)
#5 (U – Z)

Much like a human bone organ, a bone in a 3D scene is placed “inside” of the skeleton of the model. When the bone in the skeleton is moved, it reacts on the mesh, making the mesh move, thus deforming the model to fit into the skeleton.

In 3D, a Boolean is an object that is created by merging two new objects via mathematical operators. The two objects may be subtracted, merged or intersected to form a new object. See screenshot below of me using the Boolean technique on two cubes.

Bounding Box
The smallest possible regular shaped block that encloses an object.

Why would this be useful? This really does speed up a lot of maths, for example with collision detection. Instead of checking collision with hundreds of points on the model, a simple box is created.

This is also a rendering technique (See DirectX article), in which programmers check if the bounding box has any effect on the final image. If not, the object is not rendered. This saves your computer a lot of trouble and speeds up gameplay.

Bump Map
Bump mapping is a technique used to modify a 3D object based on a 2D, black and white image. When projected on the surface of a model, parts of the surface which has lighter, or white colors are raised, darker colors are lowered. This is simply a rendering effect and can make a big difference on the end effect. The actual model is not actually edited. (See Displacement map).

A clean sphere on the left, with a bump map in the middle, placed over the sphere will generate the result on the right.

A virtual viewpoint in 3D space. A camera represents the viewers eye. Everything you see on the screen of a game, is making use of a camera. A camera can move, rotate, zoom, etc. Whatever to suit the programmers need.

Camera Mapping

A technique by which geometry matching the size and perspective of objects shown within a still image is constructed, and the original image mapped back onto those objects. This permits limited camera movement around the picture, giving the illusion of a 3D environment from a 2D image.

Camera Path
The given path in 3D space in which the camera will move in a 3D scene. For example, when starting a game, some games give you a quick preview of the level. That preview you see is the image from a camera which is moving in a path.

Camera Tracking
A visual-effects technique that allows the insertion of computer graphics into other footage with correct position, scale, orientation, and motion relative to the photographed objects in the shot.

A piece of intense illumination caused by the refraction of light through a transparent object or the
reflection of light from a reflective surface. This is not easy to achieve, in mathematics, this effect would have a formula similar to this:
Luckily none of us have to worry about that. The 3D package worries about that. It does all you need. Only recently have computers be able to create this effect in a 3D environment. A common example is that reflective shine on a swimming pool on a hot sunny day.

CGI stands for computer generated imagery. This is really simple. An image created or manipulated with the help of a computer. This is used in a lot of forms, but mostly in 3D. Probably because 3D is created from scratch and not like photographs being manipulated.

Character Animation
A sub section of animation that deals with the simulation of movements of living creatures. Usually before this can be done the model has to be rigged. (See part 4).

CV stands for control vertex(See part 5). Which is a control point used to manipulate a NURBS(See part 3) curve.

Displacement Map
Similar to a Bump map, but a Displacement map modifies the actual underlining geometry and is not just a rendering effect.

Stands for Depth of Field. The depth of field of a specific lens is the range of acceptable focus in front of and behind the primary focus setting. It is a function not only of the specific lens used but
also of the distance from the lens to the primary focal plane, and of the chosen aperture. Larger apertures will narrow the depth of field, smaller apertures will increase it.

A modeling technique in which a 2D outline is duplicated outwards along a linear path. Example of extruding a flat plane.

This concludes the first section of our 3D terminology. Stay tuned, number 2 is coming soon!

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