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arXiv · 2604.12631

Topology Understanding of B-Spline Surface/Surface Intersection with Mapper

Chenming Gao·Hongwei Lin·Gengchen Li
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Abstract

In the realm of computer-aided design (CAD) software, the intersection of B-spline surfaces stands as a fundamental operation. Despite the extensive history of surface intersection algorithms, the challenge of handling complex intersection topologies persists. While subdivision algorithms have demonstrated strong robustness in computing surface/surface intersection and are capable of addressing singular cases, determining the topology of the intersection obtained through these methods is a key factor for calculating correct intersection, and remains a difficult issue. To address this challenge, we propose a Mapper-based method for determining the topology of the intersection between two B-spline surfaces. Our algorithm is designed to efficiently handle various common and complex intersection topologies. Experimental results verify the robustness and topological correctness of this method.

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Chenming Gao, Hongwei Lin, Gengchen Li. 2026-04-14. Topology Understanding of B-Spline Surface/Surface Intersection with Mapper. https://arxiv.org/abs/2604.12631

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