FlexPart puts point, box and mask prompts into one 3D part-generation model, cutting Part CD 16.6% against a two-stage pipeline
AspireAI community · arXiv (Tongji University and Chongqing Afari)
FlexPart, accepted at NeurIPS 2026, is a single diffusion-transformer model that turns one image into separate, assemblable 3D parts and accepts sparse point, bounding-box or segmentation-mask prompts at inference without retraining, using gated adaptive modulation and asymmetric geometric guidance to move information from stronger masks and boxes into weaker point prompts. Under mask conditioning on PartVerseXL the paper reports a 16.6% reduction in Part CD relative to TripoSG plus SAM3D and 10.5% relative to OmniPart, while keeping competitive whole-mesh quality. The MIT-licensed repository ships training and inference code, the transformer checkpoint and a local Gradio demo; the setup targets Linux, Python 3.11 and PyTorch 2.5.1 with CUDA 12.4, and the paper puts peak VRAM at roughly 6-8 GB. The limits the authors flag: occlusion stays hard from single-view 2D conditions, and the higher-resolution approach needs more compute than two-stage alternatives.
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