关键词: 道路工程, 网络三维可视化, 顾及约束, 道路整体建模, 三维模型简化, 误差度量

Abstract: In order to realize the Web 3D visualization of road engineering, the key technologies such as the road integrated 3D model construction and simplification methods concerning constraints were studied. Based on the theory of constrained Delaunay triangulation, the road 3D model with integrated appearance and inner topological relationship was created. A half-edge collapse error metric concerning road constrained edges was proposed. Based on it, original road model was integrated and simplified by half-edge collapse and operating hierarchical tree was built to store operation records on the server. The view-dependent strategy was put forward, in which the constrained edges were refined preferentially and simplified afterwards. Combined with the view-dependent reconstruction criterions, the transmission data for 3D visualization was substantially reduced and fast view-dependent reconstruction of the road 3D model was realized on the client. Given the benefits from above methods, a relevant system was developed out and applied to many highways Web-based construction management successfully.

Key words: road engineering, Web 3D visualization, considering constraint, road integrated model construction, 3D model simplification, error metric