Light Source
Light Source | Light SourceAn element of the scene, which creates the light. Light sources can be of different types and have different characteristics. The analogues of lighting devices in the real world, which offer additional features, inaccessible real sources.
Typically, there are three main types of light sources:
Point Light (point) is the source of light which shines equally in all directions from one point (for example, the light in the room). Also there is the omni designation (omnidirectional) light.
Spot Light (spot) - a light source shining in all directions, and within some of the cone. Highlights the only objects that fall into this cone. A simple example is the flashlight.
Parallel Light (parallel light) - simulates the remote light sources, such as the sun. The light is emitted in the direction of the only one axis, from the source, of the infinitely great distance from the viewer, and all light rays are parallel. The synonyms of the term: distant light, directional light.
Point and directed light sources are the parameters affecting the lighting, for example, attenuation (attenuation). This setting affects the decrease of light intensity with distance. In the quadratic equation that determines the intensity of the light, composed of three parameters, called constant, linear and quadratic components (constant, linear, quadratic). By default, they are assigned a value of 1, 0 and 0 respectively - the intensity of the light from the source does not decrease with distance.
The equation is as follows:
Where a is the value of the attenuation; - constant component; l is a linear component; d is the distance from the light source, a q - quadratic component.