View in EDS PDF Full Text

Bidirectional Importance Sampling for Unstructured Direct Illumination.

Saved in:
Bibliographic Details
Title: Bidirectional Importance Sampling for Unstructured Direct Illumination.
Authors: Wang, Rui1, Åkerlund, Oskar2
Source: Computer Graphics Forum. Apr2009, Vol. 28 Issue 2, p269-278. 10p. 5 Color Photographs, 2 Diagrams, 1 Chart.
Subjects: Lighting software, Computer graphics software, Ray tracing algorithms, Computer graphics research, Three-dimensional imaging, Photorealism, Statistical sampling software, Computer software
Abstract: Recent research in bidirectional importance sampling has focused primarily on structured illumination sources such as distant environment maps, while unstructured illumination has received little attention. In this paper, we present a method for bidirectional importance sampling of unstructured illumination, allowing us to use the same method for sampling both distant as well as local/indirect sources. Building upon recent work in [ WFA*05 ], we model complex illumination as a large set of point lights. The subsequent sampling process draws samples only from this point set. We start by constructing a piecewise constant approximation for the lighting using an illumination cut [ CPWAP08 ]. We show that this cut can be used directly for illumination importance sampling. We then use BRDF importance sampling followed by sample counting to update the cut, resulting in a bidirectional distribution that closely approximates the product of the illumination and BRDF. Drawing visibility samples from this new distribution significantly reduces the sampling variance. As a main advance over previous work, our method allows for unstructured sources, including arbitrary local direct lighting and one-bounce of indirect lighting. [ABSTRACT FROM AUTHOR]
Copyright of Computer Graphics Forum is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Engineering Source
FullText Links:
  – Type: pdflink
Text:
  Availability: 0
Header DbId: egs
DbLabel: Engineering Source
An: 37138292
AccessLevel: 6
PubType: Academic Journal
PubTypeId: academicJournal
PreciseRelevancyScore: 0
IllustrationInfo
Items – Name: Title
  Label: Title
  Group: Ti
  Data: Bidirectional Importance Sampling for Unstructured Direct Illumination.
– Name: Author
  Label: Authors
  Group: Au
  Data: <searchLink fieldCode="AR" term="%22Wang%2C+Rui%22">Wang, Rui</searchLink><relatesTo>1</relatesTo><br /><searchLink fieldCode="AR" term="%22Åkerlund%2C+Oskar%22">Åkerlund, Oskar</searchLink><relatesTo>2</relatesTo>
– Name: TitleSource
  Label: Source
  Group: Src
  Data: <searchLink fieldCode="JN" term="%22Computer+Graphics+Forum%22">Computer Graphics Forum</searchLink>. Apr2009, Vol. 28 Issue 2, p269-278. 10p. 5 Color Photographs, 2 Diagrams, 1 Chart.
– Name: Subject
  Label: Subjects
  Group: Su
  Data: <searchLink fieldCode="DE" term="%22Lighting+software%22">Lighting software</searchLink><br /><searchLink fieldCode="DE" term="%22Computer+graphics+software%22">Computer graphics software</searchLink><br /><searchLink fieldCode="DE" term="%22Ray+tracing+algorithms%22">Ray tracing algorithms</searchLink><br /><searchLink fieldCode="DE" term="%22Computer+graphics+research%22">Computer graphics research</searchLink><br /><searchLink fieldCode="DE" term="%22Three-dimensional+imaging%22">Three-dimensional imaging</searchLink><br /><searchLink fieldCode="DE" term="%22Photorealism%22">Photorealism</searchLink><br /><searchLink fieldCode="DE" term="%22Statistical+sampling+software%22">Statistical sampling software</searchLink><br /><searchLink fieldCode="DE" term="%22Computer+software%22">Computer software</searchLink>
– Name: Abstract
  Label: Abstract
  Group: Ab
  Data: Recent research in bidirectional importance sampling has focused primarily on structured illumination sources such as distant environment maps, while unstructured illumination has received little attention. In this paper, we present a method for bidirectional importance sampling of unstructured illumination, allowing us to use the same method for sampling both distant as well as local/indirect sources. Building upon recent work in [ WFA*05 ], we model complex illumination as a large set of point lights. The subsequent sampling process draws samples only from this point set. We start by constructing a piecewise constant approximation for the lighting using an illumination cut [ CPWAP08 ]. We show that this cut can be used directly for illumination importance sampling. We then use BRDF importance sampling followed by sample counting to update the cut, resulting in a bidirectional distribution that closely approximates the product of the illumination and BRDF. Drawing visibility samples from this new distribution significantly reduces the sampling variance. As a main advance over previous work, our method allows for unstructured sources, including arbitrary local direct lighting and one-bounce of indirect lighting. [ABSTRACT FROM AUTHOR]
– Name: AbstractSuppliedCopyright
  Label:
  Group: Ab
  Data: <i>Copyright of Computer Graphics Forum is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract.</i> (Copyright applies to all Abstracts.)
PLink https://search.ebscohost.com/login.aspx?direct=true&site=eds-live&db=egs&AN=37138292
RecordInfo BibRecord:
  BibEntity:
    Identifiers:
      – Type: doi
        Value: 10.1111/j.1467-8659.2009.01366.x
    Languages:
      – Code: eng
        Text: English
    PhysicalDescription:
      Pagination:
        PageCount: 10
        StartPage: 269
    Subjects:
      – SubjectFull: Lighting software
        Type: general
      – SubjectFull: Computer graphics software
        Type: general
      – SubjectFull: Ray tracing algorithms
        Type: general
      – SubjectFull: Computer graphics research
        Type: general
      – SubjectFull: Three-dimensional imaging
        Type: general
      – SubjectFull: Photorealism
        Type: general
      – SubjectFull: Statistical sampling software
        Type: general
      – SubjectFull: Computer software
        Type: general
    Titles:
      – TitleFull: Bidirectional Importance Sampling for Unstructured Direct Illumination.
        Type: main
  BibRelationships:
    HasContributorRelationships:
      – PersonEntity:
          Name:
            NameFull: Wang, Rui
      – PersonEntity:
          Name:
            NameFull: Åkerlund, Oskar
    IsPartOfRelationships:
      – BibEntity:
          Dates:
            – D: 01
              M: 04
              Text: Apr2009
              Type: published
              Y: 2009
          Identifiers:
            – Type: issn-print
              Value: 01677055
          Numbering:
            – Type: volume
              Value: 28
            – Type: issue
              Value: 2
          Titles:
            – TitleFull: Computer Graphics Forum
              Type: main
ResultId 1