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C..2.1 Attenuation Factor

The attenuation factor is defined to be:

\begin{displaymath}\hbox{attenuation factor} \; = {1 \over {{k_{c}} + {k_{l}d} + {k_{q}d^2}}}\end{displaymath}

where
$d =$ distance between the light's position and the vertex
$k_{c} =$ GL_ CONSTANT_ATTENUATION
$k_{l} =$ GL_ LINEAR_ATTENUATION
$k_{q} =$ GL_ QUADRATIC_ATTENUATION
If the light is directional, the attenuation factor is 1.


2001-01-10