Bounded Clustering - Finding Good Bounds on Clustered Light Transport


Clustering is a very effcient technique to apply
finite element methods to the computation of radiosity
solutions of complex scenes. Both computation time
and memory consumption can be reduced dramatically
by grouping the primitives of the input scene into a
hierarchy of clusters and allowing for light exchange
between all levels of this hierarchy. However, problems
can arise due to clustering, when gross approximations
about a cluster's content result in unsatisfactory solutions or unnecessary computations.
In the clustering approach for diffuse global illumina-
tion described in this paper, light exchange between two
objects - patches or clusters - is bounded by using
geometrical and shading information provided by every
object through a uniform interface. With this uniform
view of various kinds of objects, comparable and reliable
error bounds on the light exchange can be computed,
which then guide a standard hierarchical radiosity al-