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Next: 20.2.2 Spotlight Effect Up: 20.2 Lighting Equations Previous: 20.2 Lighting Equations

20.2.1 Attenuation Factor

The attenuation factor is defined to be:
displaymath11526
where

d = distance between the light's position and the vertex
tex2html_wrap_inline11530 GL_CONSTANT_ATTENUATION
tex2html_wrap_inline11532 GL_LINEAR_ATTENUATION
tex2html_wrap_inline11534 GL_QUADRATIC_ATTENUATION

If the light is directional, the attenuation factor is 1.