Physically based rendering-enhanced real-scene 3D modeling framework for complex curved urban buildings

This paper presents a physically based rendering–enhanced 3D modeling framework for the reconstruction of complex, curved-surface buildings. The framework integrates unmanned aerial vehicle oblique imagery with high-definition ground-level photographs and adopts a multi-software workflow involving 3ds Max for topology simplification and Substance Painter for texture coordinate correction. The proposed approach focuses on component-level modeling of irregular building structures and the correction of texture mapping errors caused by occlusions and imaging blind spots. A case study conducted in Qingdao is used to illustrate the workflow and data processing procedures, including model generation, topology optimization, and texture refinement. The framework is intended for real-scene 3D modeling applications that require detailed geometric representation and coordinated use of photogrammetric and modeling software.