Fast Approximation of Multiple Scattering in Inhomogeneous Participating Media Szirmay-Kalos László

Fast Approximation of Multiple Scattering in Inhomogeneous Participating Media

• Szirmay-Kalos László

• Liktor Gábor

• Tamás Umenhoffer

• Tóth Balázs

GI in Participating Media

Importance of approximate solutions

• Real-time visualization

• Bootstrap for an “accurate” method

• Monte Carlo (main part separation)
• Iteration (initial state)

Direct term only

• Direct term only

• Homogeneous case, diffusion approx.

Spherical layers: algorithm

• Ray marching for sample directions

• Resampling of the result at voxels

Results: head

Conclusions

• Fast approximation of the global illumination solution

• Assumes spherical symmetry

• Cost is the same as of the direct term

• Computes also the scattered term

• Applications

• Fast visualization
• Initial state for a precise solver