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4.3.3 Multiple Scattering

We use the same parameterization for the multiple scattering lookup table as for

the single scattering. To precompute multiple scattering, we process scattering

orders one by one, and for every order we perform three steps:

1. compute the J

(n)

term using the previous order L

(n−1)

for all parameter

values according to Equation (4.5);

2. compute the current order L

(n)

according to Equation (4.4);

3. accumulate the current scattering order.

Implementation details are given in Section 4.5.1.

After each scattering order is processed, we retain only the light field on the

surface, discarding the rest of the data. It must ...