What are the mainstream methods for 3D modeling of digital cities? Which domestic companies are doing better? How long does it usually take for 50km2? how much is it?

Regarding 3D modeling at the city level, the cost varies greatly according to different technical paths and usage intentions. For example, if it is simply to present the face of the city, to show the layout of the city with high fidelity, and to pay attention to the effect, it is more to use game engines to optimize materials and so on; If related urban research is carried out based on a certain business line, such as point cloud adaptation construction progress in construction, oblique shooting to restore the panoramic view of the city, etc., UAV aerial photography and data cleaning have different quotations according to different accuracy. Generally, the current oblique photography has the highest accuracy (including data cleaning) and the highest cost is 70,000-80,000 RMB/km2; If you use the whole city-level building data, that is, the component particle data such as BIM are all carried on the platform, the price may be the most expensive of all 3D modeling, including not only the BIM professional model of new buildings, but also the past buildings of the whole city. At the same time, municipal infrastructure and other aspects need to be fully reflected, and its cost and data volume are unimaginable, which must be supported by a 3D data engine supported by cloud computing.

The cost difference of the above different routes also represents a situation in the real market. In the modeling and reconstruction of massive data such as city level, many teams will say that their products and platforms can carry super-large models, but may ignore their specific technical paths, such as using game engines to present full-name high-fidelity scenes, but often do not mention the buildings on their platforms unless the project requires that data may be attached. Most models only have Mesh grids, and do not contain BIM component-level data, which is the latter. Therefore, for 3D reconstruction modeling, we need to know the scene and purpose of modeling, choose the corresponding technical route, and then consider the cost.

In addition, the above only corresponds to the cost of direct modeling, and the invisible cost also needs to be considered. For example, after the three-dimensional model is established, take the BIM professional model as an example, and its application needs the support of professional software or PaaS independent three-dimensional data engine, so as to provide the corresponding API interface to the specific digital system integration development team for visual display and development of specific business functions. And whether the three-dimensional data engine can adapt to the super-massive model supported by cloud computing, such as the triangular patch with the BIM model of a single building reaching more than 65.438+0.5 billion, and whether the standard API interface can be provided for development will directly affect the quantitative problems such as hardware procurement and development cost, which are often the parts that have a greater impact on the final budget investment of the project.