Experimental Analysis of BSDF Models

Abstract

The Bidirectional Scattering Distribution Function (BSDF) describes the appearance of an optically thin, translucent material by its interaction with light at a surface point. Various BSDF models have been proposed to represent BSDFs. In this paper, we experimentally analyze a few of BSDF models in terms of their accuracy to represent measured BSDFs, their required storage sizes and computation times. To make a fair comparison of BSDF models, we measured three samples of optically thin, translucent materials (hunter douglas, orange glass, structured glass) by using pgII gonio-photometer. Based on rendered images, required storage sizes and computation times, we compare the performance of the BSDF models. We show that datadriven BSDF models give a more accurate representation of measured BSDFs, while data-driven BSDF models require much more storage sizes and computation times.We also show that BSDF measurements from highly anisotropic translucent materials can not be expressed by an analytical BSDF model visually correctly.