X-Part: High Fidelity And Structure Coherent Shape Decomposition

Xinhao Yan1,2,*, Jiachen Xu2,*, Yang Li2,†, Changfeng Ma3,2,
Yunhan Yang4,2, Chunshi Wang5,2, Zibo Zhao2, Zeqiang Lai6,2 Yunfei Zhao2 Zhuo Chen2 Chunchao Guo2,✉
1ShanghaiTech    2Tencent Hunyuan    3NJU    4HKU    5ZJU    6CUHK
*Equal Contribution    Project Leader    Corresponding Authors

Decompose a 3D shape into complete, semantically meaningful parts.

Abstract

Generating 3D shapes at part level is pivotal for downstream applications such as mesh retopology, UV mapping, and 3D printing. However, existing part-based generation methods often lack sufficient controllability and suffer from poor semantically meaningful decomposition. To this end, we introduce $\mathcal{X}$-Part, a controllable generative model designed to decompose a holistic 3D object into semantically meaningful and structurally coherent parts with high geometric fidelity. $\mathcal{X}$-Part exploits the bounding box as prompts for the part generation and injects point-wise semantic features for meaningful decomposition. Furthermore, we design an editable pipeline for interactive part generation. Extensive experimental results show that $\mathcal{X}$-Part achieves state-of-the-art performance in part-level shape generation. This work establishes a new paradigm for creating production-ready, editable, and structurally sound 3D assets. Codes will be released for public research.

Interactive Results

Method Overview



Given input point cloud, per-point feature and part bounding boxes are extracted from P3SAM. Global and part conditions are obtained by stacking geometry token with interpolated semantic features. They are injected to multi-part diffusion process to guide shape decomposition.

Applications


3D part amodal segmentation is capable of numerous downstream applications, such as Part Editing, UV Unwrapping.

application

BibTeX

@article{yan2025x,
            title={X-Part: high fidelity and structure coherent shape decomposition},
            author={Yan, Xinhao and Xu, Jiachen and Li, Yang and Ma, Changfeng and Yang, Yunhan and Wang, Chunshi and Zhao, Zibo and
            Lai, Zeqiang and Zhao, Yunfei and Chen, Zhuo and others},
            journal={arXiv preprint arXiv:2509.08643},
            year={2025}
            }