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arXiv · 2403.19679

Geometric Illumination of Implicit Surfaces

Michal Zamboj·Jakub Řada
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Abstract

Illumination of scenes is usually generated in computer graphics using polygonal meshes. In this paper, we present a geometric method using projections. Starting from an implicit polynomial equation of a surface in 3-D or a curve in 2-D, we provide a semi-algebraic representation of each part of the construction. To solve polynomial condition systems and find constrained regions, we apply algebraic computational algorithms for computing the Gr{\" o}bner basis and cylindrical algebraic decomposition. The final selection of illuminated and self-shaded components for polynomial surfaces of a degree higher than three is discussed. The text is accompanied by visualizations of illumination of surfaces up to degree eight.

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Michal Zamboj, Jakub Řada. 2024-02-22. Geometric Illumination of Implicit Surfaces. https://doi.org/10.1007/978-3-031-71225-8_7

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