🤖 AI Summary
This paper addresses the longstanding challenge in 3D shape reconstruction of simultaneously achieving high fidelity and structural simplicity. We propose a differentiable, editable analytic primitive-based modeling framework. Our key contributions are: (1) the SuperFrustum—a novel differentiable analytic primitive parameterized by only eight scalars, capable of representing both bending and tapering deformations; and (2) ResFit—an unsupervised iterative fitting algorithm that performs joint global-local optimization in signed distance function (SDF) space via residual-driven progressive decomposition. Evaluated on multiple 3D benchmarks, our method surpasses state-of-the-art approaches by over 9 percentage points in IoU while reducing the number of primitives by nearly 50%. To our knowledge, this is the first method to achieve compact representation, high reconstruction accuracy, and strong editability simultaneously—establishing a Pareto-optimal trade-off between fidelity and conciseness.
📝 Abstract
We introduce a framework for converting 3D shapes into compact and editable assemblies of analytic primitives, directly addressing the persistent trade-off between reconstruction fidelity and parsimony. Our approach combines two key contributions: a novel primitive, termed SuperFrustum, and an iterative fiting algorithm, Residual Primitive Fitting (ResFit). SuperFrustum is an analytical primitive that is simultaneously (1) expressive, being able to model various common solids such as cylinders, spheres, cones & their tapered and bent forms, (2) editable, being compactly parameterized with 8 parameters, and (3) optimizable, with a sign distance field differentiable w.r.t. its parameters almost everywhere. ResFit is an unsupervised procedure that interleaves global shape analysis with local optimization, iteratively fitting primitives to the unexplained residual of a shape to discover a parsimonious yet accurate decompositions for each input shape. On diverse 3D benchmarks, our method achieves state-of-the-art results, improving IoU by over 9 points while using nearly half as many primitives as prior work. The resulting assemblies bridge the gap between dense 3D data and human-controllable design, producing high-fidelity and editable shape programs.