Contains different types of light sources.
Omni-directional, fixed-intensity and fixed-color light source that affects all objects in the scene equally.
The light source that illuminates all objects equally from a given direction, like an area light of infinite size and infinite distance from the scene; there is shading, but cannot be any distance falloff.
Internal data for
Light originates from a single point, and spreads outward in all directions.
Marks light sources and implements their common methods.