## A unified hierarchical algorithm for global illumination with scattering volumes and object clusters (1995)

Venue: | IEEE Trans. Vis. Comput. Graph |

Citations: | 105 - 22 self |

### BibTeX

@ARTICLE{Sillion95aunified,

author = {François X. Sillion},

title = {A unified hierarchical algorithm for global illumination with scattering volumes and object clusters},

journal = {IEEE Trans. Vis. Comput. Graph},

year = {1995},

pages = {240--254}

}

### Years of Citing Articles

### OpenURL

### Abstract

Abstract — This paper presents a new radiosity algorithm that allows the simultaneous computation of energy exchanges between surface elements, scattering volume distributions, and groups of surfaces, or object clusters. The new technique is based on a hierarchical formulation of the zonal method, and efficiently integrates volumes and surfaces. In particular no initial linking stage is needed, even for inhomogeneous volumes, thanks to the construction of a global spatial hierarchy. An analogy between object clusters and scattering volumes results in a powerful clustering radiosity algorithm, with no initial linking between surfaces and fast computation of average visibility information through a cluster. We show that the accurate distribution of the energy emitted or received at the cluster level can produce even better results than isotropic clustering at a marginal cost. The resulting algorithm is fast and, more importantly, truly progressive as it allows the quick calculation of approximate solutions with a smooth convergence towards very accurate simulations. I.

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