• Login
    View Item 
    •   Eurographics DL Home
    • Computer Graphics Forum
    • Volume 33 (2014)
    • 33-Issue 4
    • View Item
    •   Eurographics DL Home
    • Computer Graphics Forum
    • Volume 33 (2014)
    • 33-Issue 4
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Importance Sampling Microfacet-Based BSDFs using the Distribution of Visible Normals

    Thumbnail
    View/Open
    v33i4pp103-112.pdf (2.121Mb)
    supplemental1.pdf (1019.Kb)
    supplemental2.pdf (5.453Mb)
    Date
    2014
    Author
    Heitz, Eric
    d'Eon, Eugene
    Pay-Per-View via TIB Hannover:

    Try if this item/paper is available.

    Metadata
    Show full item record
    Abstract
    We present a new approach to microfacet-based BSDF importance sampling. Previously proposed sampling schemes for popular analytic BSDFs typically begin by choosing a microfacet normal at random in a way that is independent of direction of incident light. To sample the full BSDF using these normals requires arbitrarily large sample weights leading to possible fireflies. Additionally, at grazing angles nearly half of the sampled normals face away from the incident ray and must be rejected, making the sampling scheme inefficient. Instead, we show how to use the distribution of visible normals directly to generate samples, where normals are weighted by their projection factor toward the incident direction. In this way, no backfacing normals are sampled and the sample weights contain only the shadowing factor of outgoing rays (and additionally a Fresnel term for conductors). Arbitrarily large sample weights are avoided and variance is reduced. Since the BSDF depends on the microsurface model, we describe our sampling algorithm for two models: the V-cavity and the Smith models. We demonstrate results for both isotropic and anisotropic rough conductors and dielectrics with Beckmann and GGX distributions.
    BibTeX
    @article {10.1111:cgf.12417,
    journal = {Computer Graphics Forum},
    title = {{Importance Sampling Microfacet-Based BSDFs using the Distribution of Visible Normals}},
    author = {Heitz, Eric and d'Eon, Eugene},
    year = {2014},
    publisher = {The Eurographics Association and John Wiley and Sons Ltd.},
    ISSN = {1467-8659},
    DOI = {10.1111/cgf.12417}
    }
    URI
    http://dx.doi.org/10.1111/cgf.12417
    Collections
    • 33-Issue 4
    • EGSR14: 25th Eurographics Symposium on Rendering

    Eurographics Association copyright © 2013 - 2021 
    Send Feedback | Contact - Imprint | Data Privacy Policy | Disable Google Analytics
    Theme by @mire NV
    System hosted at  Graz University of Technology.
    TUGFhA
     

     

    Browse

    All of Eurographics DLCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

    My Account

    LoginRegister

    BibTeX | TOC

    Create BibTeX Create Table of Contents

    Eurographics Association copyright © 2013 - 2021 
    Send Feedback | Contact - Imprint | Data Privacy Policy | Disable Google Analytics
    Theme by @mire NV
    System hosted at  Graz University of Technology.
    TUGFhA