Research on the Construction of Large-Scale 3D Real Scene Coordinate System and Model Tile Division: A Case Study of Hunan Province, China

3D real scene is characterized by three-dimensional visualization, semantic enrichment, structural organization, full-space coverage, and human-machine compatible understanding, providing a unified spatial positioning framework and analytical foundation for Digital China. With the continuous advancement of 3D real scene construction, the volume of 3D models has grown exponentially. However, during the current process of data acquisition and production of 3D real scene, the coordinate systems used for model tiles lack unified construction criteria, and the division and numbering of tiles lack standardized rules. This significantly increases the difficulty of managing, retrieving, and updating massive 3D real scene data. To address these issues, this paper proposes a method for constructing a large-scale 3D real scene coordinate system and dividing model tiles, taking into account cross-projection zones. Using Hunan Province as an example, the proposed method was tested with its specific 3D real scene data characteristics. The results show that this method achieved unified coordinate benchmarks for 3D real scene tiles across Hunan Province, enabling standardized tile division and numbering for the entire province. Consequently, it greatly reduced the difficulty of managing, retrieving, and updating massive 3D real scene data. This method has been implemented province-wide in Hunan as the standard for constructing model coordinate systems and dividing model tiles in 3D real scene construction.