Research On Road Network Semantic Modeling Supporting Dynamic Editing

Virtual traffic has become a new research topic in the field of computer graphics in recent years.In a virtual traffic simulation process,when users intuitively see the simulation process,they usually want to integrate their traffic imaginations: whether it will be better,if widening / closing /deleting a road when there are heavy traffic jams.However,there are tight couplings among road network lanes in existing road network models.Editing and modifying a lane may affect the entire road network.The whole road network semantic data need to be recalculated.So once road network semantic data are determined,existing models do not allow users to edit and modify them.Combined with the theoretical methods in the field of geometric topology,this dissertation proposes a road network semantic method that supports dynamic editing.Firstly,this paper introduces the concept of generalized lanes,and uses the idea of symbol network to semantically model the vector data of road network to reduce the tight coupling relationship between intersection lanes and traditional lanes.Intersection lanes can then be automatically generated according to traditional lanes.In order to save storages,increase computing efficiencies and enhance the dynamic adjustment ability of the topology near intersections,this paper uses the compression point sequence and the offset under the Frenet frame to characterize vector data of generalized lanes.Secondly,this paper presents a hierarchical semantic method for road network topology data based on the vector data mentioned above to reduce the influence of lane-editing on the road network topological structure.Simulation results show that this method can automatically generate intersection lanes.The established road network semantic data is editable,which can satisfy users' various dynamic editing requirements in virtual traffic simulation processes.