Paper: An Area Preserving Parametrization for Spherical Rectangles

Article Info

Title	An Area Preserving Parametrization for Spherical Rectangles
Authors	Carlos Ureña, Marcos Fajardo, Alan King
Published in	Eurographics Symposium on Rendering 2013. Nicolas Holzschuch and Szymon Rusinkiewicz (Guest Editors). Computer Graphics Forum, Volume 32 (2013), Number 4, pp. 59-66. Ed. Wiley, 2013.
doi	10.1111/cgf.12151
paper page	at Computer Graphics Forum web site at Eurographics Digital Library web site

Abstract

We present an area-preserving parametrization for spherical rectangles which is an analytical function with domainin the unit rectangle [0,1]² and range in a region included in the unit-radius sphere. The parametrization preserves areas up to a constant factor and is thus very useful in the context of rendering as it allows to map random sample point sets in [0,1]² onto the spherical rectangle. This allows for easily incorporating stratified, quasi-Monte Carlo or other sampling strategies in algorithms that compute scattering from planar rectangular emitters.

Categories and Subject Descriptors (according to ACM CCS) :

I.3.7 [Computer Graphics]: Three-Dimensional Graphics and Realism — Color, shading, shadowing, and texture

Documents

• paper in pdf (10 MB)
• EGSR 2013 presentation slides in pdf (8,5 MB)

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