Using the Modified Phong brdf for Physically Based Rendering
Eric P. Lafortune and
Yves D. Willems
Report CW197, Department of Computer Science, K.U.Leuven (November 1994).
This text discusses a few aspects of reflectance models in physically based
- The first section presents the definition of the bidirectional
reflection distribution function (brdf) of a surface and
its physical properties.
- On a more practical level, the next section discusses models to
represent brdfs and their desired properties in general for
Monte Carlo algorithms.
- The third section goes into details about a specific reflectance
model, the modified Phong brdf, with its definition, its
properties and its use. We show how this model can be correctly
integrated in importance sampling schemes for physically based Monte
Carlo rendering algorithms.
- The fourth section is devoted to alternative parameter spaces in which
reflectance models can be sampled, either deterministically or stochastically.
- The last section discusses an important implementational issue, more
specifically the problem of verifying the implementation of a reflectance
This Technical Report is available on-line as a
gzip'ed Postscript file
(19 pages, 117 KBytes, expands to 725 KBytes).
Copyright © 1996-2016 Eric Lafortune.