SymPoint Revolutionized: Boosting Panoptic Symbol Spotting with Layer Feature Enhancement
Wenlong Liu, Tianyu Yang, Qizhi Yu, Lei Zhang
TL;DR
SymPoint-V2 tackles panoptic symbol spotting in CAD drawings by addressing two key drawbacks of the prior approach: neglect of graphical layer information and slow early-stage convergence. It introduces a Layer Feature-Enhanced (LFE) module to fuse layer context into primitive features, and a Position-Guided Training (PGT) strategy that uses center queries to stabilize and accelerate learning in the transformer decoder. On FloorPlanCAD, SPv2 achieves state-of-the-art performance, notably a panoptic quality (PQ) of 90.1 and substantial gains in semantic and instance spotting over SPv1, while maintaining reasonable training and inference efficiency. The work advances CAD parsing for BIM and engineering workflows by delivering more accurate, layer-aware symbol spotting with improved training dynamics and practical deployment potential.
Abstract
SymPoint is an initial attempt that utilizes point set representation to solve the panoptic symbol spotting task on CAD drawing. Despite its considerable success, it overlooks graphical layer information and suffers from prohibitively slow training convergence. To tackle this issue, we introduce SymPoint-V2, a robust and efficient solution featuring novel, streamlined designs that overcome these limitations. In particular, we first propose a Layer Feature-Enhanced module (LFE) to encode the graphical layer information into the primitive feature, which significantly boosts the performance. We also design a Position-Guided Training (PGT) method to make it easier to learn, which accelerates the convergence of the model in the early stages and further promotes performance. Extensive experiments show that our model achieves better performance and faster convergence than its predecessor SymPoint on the public benchmark. Our code and trained models are available at https://github.com/nicehuster/SymPointV2.
