Abstract

Light-driven global illumination is intermediate between local and global illumination. Representing light with wavelet basis functions, we are able to treat both the interaction between two surfaces and the interaction of a surface with a radiation field in a source-to-destination model that applies to whole surfaces, not just small elements.

We have found this ``wavelet radiative transfer'' to be a valid way to generate and store complex global light field data as four-dimensional textures for incorporation in local illumination solutions. Wavelets can considerably reduce the otherwise substantial storage and reconstruction problems associated with doing this. We include several examples of this.

We also discuss plausible illumination models, which are required to make light-driven global illumination work theoretically. Like wavelet radiative transfer, these models have application in other areas of rendering besides global illumination.

Finally, we develop the theory behind light-driven global illumination and apply it successfully to some simple examples. While we find the algorithm to be quite slow compared to other well-known rendering algorithms, we analyze what is needed to make it competitive.

In conclusion, we find that representing light with wavelets has a set of advantages that are independent of the comparative inefficiency of the light-driven algorithm.

@PhdThesis{Lewis1998,
	author = {Robert R. Lewis, Ph.D},
	title = {Light-Driven Global Illumination with a Wavelet Representation of Light Transport},
	school = {UBC},
	year = {1998},
	supervisor = {Alain Fournier},
}