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Next: 18.2.2 Spotlight Effect Up: 18.2 Lighting Equations Previous: 18.2 Lighting Equations

18.2.1 Attenuation Factor

The attenuation factor is defined to be:
displaymath8219
where

d = distance between the light's position and the vertex
tex2html_wrap_inline8223 GL_CONSTANT_ATTENUATION
tex2html_wrap_inline8225 GL_LINEAR_ATTENUATION
tex2html_wrap_inline8227 GL_QUADRATIC_ATTENUATION

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


David Blythe
Thu Jul 17 21:24:28 PDT 1997