LayoutBridge: Anisotropic Brownian Bridges for Public Indoor Floorplan Generation

Compared with residential layouts, public indoor floorplans present more substantial challenges with open corridors, complex room relations, and non-Manhattan geometries, which do not conform to conventional residential-layout assumptions. Consequently, existing methods are prone to boundary discontinuities, leading to fragmented corridors and irregular wall structures. To address the above issues, we propose \textit{LayoutBridge}, a structure-conditioned generative framework for floorplan production. By moving beyond the Manhattan-geometry assumptions commonly adopted in residential scenarios, LayoutBridge reformulates the task as a latent-space Brownian-bridge diffusion process from structural constraints to target layouts. We have constructed our PISF dataset with 3,517 representative floorplans in public indoor spaces, and LayoutBridge reduces FID by 132.35 and improves BIoU by 15.52\% over the latest image-to-image baselines. Regarding the residential benchmarks MSD and RPLAN, it also reduces FID by at least 2.53 compared with state-of-the-art. These results demonstrate its potential for scalable automated architectural design. Code implementing the proposed method is publicly available at \href{http://github.com/lalalalaxxx/LayoutBridge}{http://github.com/lalalalaxxx/LayoutBridge}.