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arXiv · 2603.11851

Fast and exact visibility on digitized shapes and application to saliency-aware normal estimation

Romain Negro·Jacques-Olivier Lachaud
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Abstract

Computing visibility on a geometric object requires heavy computations since it requires to identify pairs of points that are visible to each other, i.e. there is a straight segment joining them that stays in the close vicinity of the object boundary. We propose to exploit a specic representation of digital sets based on lists of integral intervals in order to compute eciently the complete visibility graph between lattice points of the digital shape. As a quite direct application, we show then how we can use visibility to estimate the normal vector eld of a digital shape in an accurate and convergent manner while staying aware of the salient and sharp features of the shape.

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Romain Negro, Jacques-Olivier Lachaud. 2026-03-12. Fast and exact visibility on digitized shapes and application to saliency-aware normal estimation. https://arxiv.org/abs/2603.11851

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