3D Graphics Programming with QuickDraw 3D 1.5.4
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Light Attenuation Values
Most types of lights have an attenuation value that determines how quickly, if at all, the intensity of a light changes as a function of the distance of the illuminated object from the light source. You can use these constants to specify an attenuation value:
typedef enum TQ3AttenuationType {
kQ3AttenuationTypeNone,
kQ3AttenuationTypeInverseDistance,
kQ3AttenuationTypeInverseDistanceSquared
} TQ3AttenuationType;
Constant descriptions
- kQ3AttenuationTypeNone
- The intensity of the light is not affected by the distance from the illuminated object.
- kQ3AttenuationTypeInverseDistance
- The intensity of the light is inversely proportional to the distance from the illuminated object.
- kQ3AttenuationTypeInverseDistanceSquared
- The intensity of the light is inversely proportional to the square of the distance from the illuminated object.
© 1997 Apple Computer, Inc.
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