Exploiting visibility correlation in direct illumination
(2008) In Computer Graphics Forum 27(4). p.1125-1136- Abstract
- The visibility function in direct illumination describes the binary visibility over a light source, e.g., an environment map. Intuitively, the visibility is often strongly correlated between nearby locations in time and space, but exploiting this correlation without introducing noticeable errors is a hard problem. In this paper, we first study the statistical characteristics of the visibility function. Then, we propose a robust and unbiased method for using estimated visibility information to improve the quality of Monte Carlo evaluation of direct illumination. Our method is based on the theory of control variates, and it can be used on top of existing state-of-the-art schemes
for importance sampling. The visibility estimation is... (More) - The visibility function in direct illumination describes the binary visibility over a light source, e.g., an environment map. Intuitively, the visibility is often strongly correlated between nearby locations in time and space, but exploiting this correlation without introducing noticeable errors is a hard problem. In this paper, we first study the statistical characteristics of the visibility function. Then, we propose a robust and unbiased method for using estimated visibility information to improve the quality of Monte Carlo evaluation of direct illumination. Our method is based on the theory of control variates, and it can be used on top of existing state-of-the-art schemes
for importance sampling. The visibility estimation is obtained by sparsely sampling and caching the 4D visibility
field in a compact bitwise representation. In addition to Monte Carlo rendering, the stored visibility information
can be used in a number of other applications, for example, ambient occlusion and lighting design. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1152610
- author
- Clarberg, Petrik LU and Akenine-Möller, Tomas LU
- organization
- publishing date
- 2008
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Visibility, Ray tracing, Photo-realistic rendering, Monte Carlo techniques, Computer graphics, Direct illumination, Control variates
- in
- Computer Graphics Forum
- volume
- 27
- issue
- 4
- pages
- 1125 - 1136
- publisher
- Wiley-Blackwell
- external identifiers
-
- wos:000258223600009
- scopus:51549103078
- ISSN
- 1467-8659
- DOI
- 10.1111/j.1467-8659.2008.01250.x
- language
- English
- LU publication?
- yes
- id
- 49a95691-21a5-4ff4-9044-b1fd4c88cc36 (old id 1152610)
- date added to LUP
- 2016-04-01 12:04:47
- date last changed
- 2022-01-26 22:29:38
@article{49a95691-21a5-4ff4-9044-b1fd4c88cc36, abstract = {{The visibility function in direct illumination describes the binary visibility over a light source, e.g., an environment map. Intuitively, the visibility is often strongly correlated between nearby locations in time and space, but exploiting this correlation without introducing noticeable errors is a hard problem. In this paper, we first study the statistical characteristics of the visibility function. Then, we propose a robust and unbiased method for using estimated visibility information to improve the quality of Monte Carlo evaluation of direct illumination. Our method is based on the theory of control variates, and it can be used on top of existing state-of-the-art schemes <br/><br> for importance sampling. The visibility estimation is obtained by sparsely sampling and caching the 4D visibility <br/><br> field in a compact bitwise representation. In addition to Monte Carlo rendering, the stored visibility information <br/><br> can be used in a number of other applications, for example, ambient occlusion and lighting design.}}, author = {{Clarberg, Petrik and Akenine-Möller, Tomas}}, issn = {{1467-8659}}, keywords = {{Visibility; Ray tracing; Photo-realistic rendering; Monte Carlo techniques; Computer graphics; Direct illumination; Control variates}}, language = {{eng}}, number = {{4}}, pages = {{1125--1136}}, publisher = {{Wiley-Blackwell}}, series = {{Computer Graphics Forum}}, title = {{Exploiting visibility correlation in direct illumination}}, url = {{http://dx.doi.org/10.1111/j.1467-8659.2008.01250.x}}, doi = {{10.1111/j.1467-8659.2008.01250.x}}, volume = {{27}}, year = {{2008}}, }