article

Area-Preserving Parameterizations for Spherical Ellipses

Authors:

Ibón Guillén,

Marcos Fajardo,

Iliyan Georgiev,

Jorge López-Moreno,

Adrian JaraboAuthors Info & Claims

Computer Graphics Forum, Volume 36, Issue 4

Pages 179 - 187

https://doi.org/10.1111/cgf.13234

Published: 01 July 2017 Publication History

Abstract

We present new methods for uniformly sampling the solid angle subtended by a disk. To achieve this, we devise two novel area-preserving mappings from the unit square [0,1]2 to a spherical ellipse i.e. the projection of the disk onto the unit sphere. These mappings allow for low-variance stratified sampling of direct illumination from disk-shaped light sources. We discuss how to efficiently incorporate our methods into a production renderer and demonstrate the quality of our maps, showing significantly lower variance than previous work.

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Cited By

Peters C(2021)BRDF importance sampling for polygonal lightsACM Transactions on Graphics10.1145/3450626.345967240:4(1-14)Online publication date: 19-Jul-2021
https://dl.acm.org/doi/10.1145/3450626.3459672
Peters CDachsbacher C(2019)Sampling Projected Spherical Caps in Real TimeProceedings of the ACM on Computer Graphics and Interactive Techniques10.1145/33202822:1(1-16)Online publication date: 3-Jun-2019
https://dl.acm.org/doi/10.1145/3320282
Georgiev IIze TFarnsworth MMontoya-Vozmediano RKing ALommel BJimenez AAnson OOgaki SJohnston EHerubel ARussell DServant FFajardo M(2018)ArnoldACM Transactions on Graphics10.1145/318216037:3(1-12)Online publication date: 1-Aug-2018
https://dl.acm.org/doi/10.1145/3182160
Show More Cited By

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Information & Contributors

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Published In

cover image Computer Graphics Forum

Computer Graphics Forum Volume 36, Issue 4

July 2017

181 pages

ISSN:0167-7055

EISSN:1467-8659

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Publisher

The Eurographs Association & John Wiley & Sons, Ltd.

Chichester, United Kingdom

Publication History

Published: 01 July 2017

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Cited By

Peters C(2021)BRDF importance sampling for polygonal lightsACM Transactions on Graphics10.1145/3450626.345967240:4(1-14)Online publication date: 19-Jul-2021
https://dl.acm.org/doi/10.1145/3450626.3459672
Peters CDachsbacher C(2019)Sampling Projected Spherical Caps in Real TimeProceedings of the ACM on Computer Graphics and Interactive Techniques10.1145/33202822:1(1-16)Online publication date: 3-Jun-2019
https://dl.acm.org/doi/10.1145/3320282
Georgiev IIze TFarnsworth MMontoya-Vozmediano RKing ALommel BJimenez AAnson OOgaki SJohnston EHerubel ARussell DServant FFajardo M(2018)ArnoldACM Transactions on Graphics10.1145/318216037:3(1-12)Online publication date: 1-Aug-2018
https://dl.acm.org/doi/10.1145/3182160
Fascione LHanika JFajardo MChristensen PBurley BGreen B(2017)Path tracing in production - part 1ACM SIGGRAPH 2017 Courses10.1145/3084873.3084904(1-39)Online publication date: 30-Jul-2017
https://dl.acm.org/doi/10.1145/3084873.3084904

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