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.

翻译：在几何对象上计算可见性需要大量计算，因为它需要识别相互可见的点对，即存在一条连接它们的直线段，且该线段保持在对象边界附近。我们提出利用基于整数区间列表的数字集合特定表示，以高效计算数字形状格点之间的完整可见性图。作为一个相当直接的应用，我们随后展示了如何利用可见性以精确且收敛的方式估计数字形状的法向量场，同时保持对形状显著和尖锐特征的感知。