Adaptive Mesh-Free Numerical Integration on Algebraic Surfaces Using Local Polynomial Reconstruction
This paper presents AMNI-AS, a compact method and Python package for surface integration on non-parametrized geometries known only through point-cloud samples. The method extends a corrected minterpy_levelsets [9] workflow: first, a global polynomial level-set function ϕ_h reconstructs the surface as Γ_h={x∈R^3:ϕ_h (x)=0}; [6] second, nodal values of the integrand are extended by regression; third, a closest-point projection and a regularized coarea formula [4], [5], produce a mesh-free quadrature rule. The theoretical core is the identity ∫_(Γ_h)▒ fdS=∫_Ω▒ f(x)δ(ϕ_h (x))‖∇ϕ_h (x)‖dx, implemented with a compact smooth delta and data-driven evaluation f ˜_h (Π_h (x)). The prototype package AMNI-AS, contains adapters to minterpy_levelsets, an SVD fallback level-set fit, RBF/nearest integrand regression [3], [15], [16], [17], projection, and quadrature routines. Numerical checks on the unit sphere show relative errors near 〖10〗^(-5) for area and polynomial integrands on a moderate grid. The method is intended as a short, reproducible bridge from global polynomial level-set reconstruction to integration tasks on data-defined surfaces.