MAM2014: Eurographics Workshop on Material Appearance Modeling: Issues and Acquisition

Permanent URI for this collection

https://diglib.eg.org/handle/10.2312/7759

Browse

Browsing MAM2014: Eurographics Workshop on Material Appearance Modeling: Issues and Acquisition by Subject "Three Dimensional Graphics and Realism"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Linear Transport Theory and Applications to Rendering
    (The Eurographics Association, 2014) Jakob, Wenzel; Reinhard Klein and Holly Rushmeier
    In this talk, I will give an overview of one-dimensional Linear Transport Theory, which concerns itself with the study of random scattering and absorption processes and the inference of large-scale behavior from simple local scattering models. Research over the last 75 years has led to a rich toolbox of solution techniques for these types of problems, including Monte Carlo, Diffusion Theory, H-functions, Discrete Ordinates, and the Adding-Doubling method. I will give an intuitive overview of each of these techniques and discuss advantages and disadvantages. Following this, I will discuss how this problem is relevant to rendering, where it leads to a flexible and efficient method for rendering general layered materials.
  • Thumbnail Image
    Item
    Reducing Anisotropic BSDF Measurement to Common Practice
    (The Eurographics Association, 2014) Ward, Greg; Kurt, Murat; Bonneel, Nicolas; Reinhard Klein and Holly Rushmeier
    We address the problem of measuring and representing reflection and transmission for anisotropic materials without relying on mathematical models or a large sample database. By eliminating assumptions of material behavior, we arrive at a general method that works for any surface class, from metals to fabrics, fritted glazing, and prismatic films. To make data gathering practical, we introduce a robust analysis method that interpolates a sparse set of incident angle measurements to obtain a continuous function over the full 4-D domain. We then convert this interpolant to a standard representation tailored for efficient rendering and supported by a common library that facilitates data sharing. We conclude with some remaining challenges to making anisotropic BSDF measurements truly practical for rendering
  • Thumbnail Image
    Item
    Statistical Characterization of Surface Reflectance
    (The Eurographics Association, 2014) Havran, Vlastimil; Sbert, Mateu; Reinhard Klein and Holly Rushmeier
    The classification of surface reflectance functions as diffuse, specular, and glossy has been introduced by Heckbert more than two decades ago. Many rendering algorithms are dependent on such a classification, as different kinds of light transport will be handled by specialized methods, for example caustics require specular bounce or refraction. Due to the increasing wealth of surface reflectance models including those based on measured data, it has not been possible to keep such a characterization simple. Each surface reflectance model is mostly handled separately, or alternatively, the rendering algorithm restricts itself to the use of some subset of reflectance models. We suggest a characterization for arbitrary surface reflectance representation by standard statistical tools, namely normalized variance known as Squared-Coefficient-of-Variation (SCV).We show by videos that there is even a weak perceptual correspondence with the proposed reflectance characterization, when we use monochromatic surface reflectance and the images are normalized so they have the unit albedo.