# Glossary

## Numerics

3D texture An image defined for every point of the 3D space and thus, seeming to be sculpted in a material block

## A

accuracy A parameter enabling to define the degree of precision of the rendering quality
area light source A source of light similar to ordinary light sources and designed to create a soft, and thus more realistic, lighting. Compare light source
attenuation The action of lessening illumination

## B

bump mapping A technique based on a texture and introducing apparent surface deviations from its original shape (such as waves of the sea or pleated leather)

## C

camera A rectangular-shaped element with a lens used to specify the chosen viewpoint to take the image
caustics Light patterns formed on other objects by the reflection or transmission of light striking a reflective or refractive surface

## D

depth of field A visual effect making objects that are not in focus appear blurry, thus giving a sense of depth to the image.
diffuse lighting The intensity of light diffused by the object when lit by light sources
directional light A light coming from a given direction (like the sun, for instance) generating constant intensity parallel lighting

## E

environment A geometrical element, either rectangular, cylindrical or spherical, used to simulate interior as well as exterior scenes

## F

Final Gathering A method used to compute light energy on any surfaces surrounding an object in the scene. Synonym: "indirect illumination"

## G

global illumination A simulation of indirect illumination of objects by diffuse interreflection of light coming from diffuse surfaces
glow A visual effect generating a halo around bright pixels of the rendered image.

## L

light source A source of light illuminating the object to be rendered

## M

mapping A method used to apply an image onto an object in order this object acquires a surface texture
material An object that can be mapped onto a geometry to simulate visually and physically the components an object is made of (e.g. wood, stone, etc.)

## P

photon An energy particle emitted in the scene by a light source
point light A punctual illumination (like a bulb, for instance) emitting light isotropically, i.e. in all directions

## R

raytracing A rendering technique producing photo-realistic images resulting from the calculation of the path of light reaching the product from various angles. Each pixel is created by calculating the behavior of a number of rays from these different points over the area covered by that pixel
reflection A light wave returned from a surface
reflectivity The ability to reflect light
refraction The degree of light passing obliquely through an object
rendering A photo-realistic drawing of three-dimensional objects

## S

scene A reusable configuration enabling to put models on stage using cameras, light sources, environments, turntables
shooting A set of parameters used to define a rendering
specular lighting The dullness of an object
spot light A light source emitting the light isotropically inside a cone of influence determined by the privileged direction of illumination (forming the axis of revolution) and the angle that the edge of the cone forms with this axis.

## T

texture An image that can be mapped onto a geometry
transparency The degree of transparency of an object. The object transparency defines its property of transmitting light so that elements lying beyond are seen