2010

Table Of Contents
Lesson 4: Global Illumination
Introduction
The mental ray
®
for Maya
®
renderer can render using a feature called Global
Illumination. Global Illumination simulates the effect of all lighting and
inter-reflection in the scene, whether the items are lit directly by a light source
or indirectly illuminated by other objects (and diffuse sources of illumination
in the scene).
For example, when a photographer lights an object in a studio, some of the
lighting for the object in the final image comes directly from the lights that
are used, while additional illumination comes from objects that are placed
near the subject to act as light reflectors. These are referred to as fill cards.
Light bounces off the fill cards, indirectly lighting nearby objects with a
secondary source of diffuse light. The color of the fill card colors the light that
gets reflected onto the object. The final illumination of the object comes from
this combination of multiple sources (direct light, specular reflections, and
diffuse light).
Lesson 4: Global Illumination | 501