Hanxiao Wang

Generating high-quality triangle meshes is essential for film, gaming, and interactive 3D applications. Mainstream methods rely on mesh serialization and autoregressive processes, which stuggles in effective inference and is sensitive to error accumulation. In this paper, we present Nexus , a diffusion method that achieves holistic mesh generation via decoupled vertex and topology generation. First, we view mesh vertices as sparse voxels organized as an octree and adopt a diffusion model to generate the vertices in a coarse-to-fine manner. Second, for topology modeling, we propose Space-time Interval , as an extension of Spacetime Distance to encode arbitrary edge and face topology into continuous per-vertex embeddings. It allows for a global and efficient recovery of complex topology. We then employ a diffusion model to generate the continuous embeddings on the generated vertices. Extensive experiments on the Objaverse and Toys4K datasets and in-the-wild images demonstrate that our method outperforms state-of-the-art autoregressive and two-stage baselines, effectively circumventing the inherent limitations of sequential mesh modeling. A blind user study from 3D practitioners confirms strong perceptual preference for our results.

Point cloud normal estimation is a fundamental task in 3D geometry processing, playing a crucial role in applications such as 3D reconstruction, object recognition, and surface analysis. While recent learning-based methods achieve notable advancements in normal prediction, they often overlook the critical aspect of equivariance. This oversight leads to inefficient learning of symmetric patterns inherent in geometric data. To address this issue, we propose E$^{3}$-Net, an innovative neural network architecture designed to inherently achieve equivariance for normal estimation. We introduce an efficient random frame method, which significantly reduces the training resources required for this task to just 1/8 of previous work, while simultaneously enhancing prediction accuracy. Furthermore, we design a Gaussian-weighted loss function and a receptive-aware inference strategy that effectively leverage the local properties of point clouds, ensuring more precise and reliable normal estimation. Our method demonstrates superior performance across both synthetic and real-world datasets, consistently outperforming current state-of-the-art techniques by a substantial margin. Specifically, we achieve a 4% improvement in RMSE on the PCPNet dataset, 2.67% on the SceneNN dataset, and 2.44% on the FamousShape dataset, highlighting the robustness and scalability of E$^{3}$-Net in diverse environments.

Filleting is a fundamental operation in CAD systems, akin to a ball rolling between two adjacent surface patches, resulting in a seamless connection. The reverse process, which we refer to as DeFillet in this paper, is crucial for CAE analysis and secondary design phases. However, it presents significant challenges, particularly when the input data originates from surface reconstruction or discretization processes. Our DeFillet algorithm is inspired by the observation that the rolling-ball center defines an osculating sphere, while the Voronoi diagram of surface samples provides sufficiently many rolling-ball center candidates. By leveraging this insight, we compute a transformation between the Voronoi vertices and the surface samples, enabling the efficient identification of fillet regions. Subsequently, we formulate the reconstruction of sharp features as a quadratic optimization problem. Our method's effectiveness has been validated through extensive testing using self-constructed models and 100 filleted models selected from the Fusion 360 Gallery dataset. The code for this paper is publicly available at https://github.com/xiaowuga/DeFillet.