Urban design computer vision simulation needs to solve several problems. First, the digital elevation model is processed, and the three-dimensional terrain is generated and modified, and the slope, the aspect, the elevation, the filling and digging, the flooding, and the visual field of view are analyzed. Second, the building density, floor area ratio, accessibility, buffering, and site selection feasibility analysis are used to evaluate the socio-economic and environmental effects. The above two are typical functions of GIS. Third, rapid three-dimensional modeling of large-area multi-units, including buildings, structures, urban furniture, billboards, trees, vehicles, people, etc. General GIS only has a two-dimensional stretching function, called 2.5-dimensional, not true three-dimensional. The popular 3Dmax 3D modeling is not capable of a large number of object modeling and real-time browsing tasks. Fourth, real-time virtual. To be able to quickly repaint the surface, including changes to the scene object, skylight background, animation path, viewpoint perspective, etc., can respond immediately. In theory, the above four problems can be solved in a GIS platform or a unified VR system, but at present the platform is still in development, but we can solve the problem by integrating GIS and VR.
2 A GIS-based and VR-based urban design technical solution 2.1 virtual reality system integration. Whether it is GIS or VR, there are a variety of commercial software available at home and abroad. ESRI's ArcGIS is the world's most advanced geographic information system, but its 3D modeling capabilities are not strong and there is no real-time virtual animation. Multigen-Vega of Multigen-Paradigm is the current flagship software of virtual reality. Its powerful 3D modeling tool Creator and virtual simulation engine Vega can meet the virtual city real-time animation requirements well, but it does not have spatial analysis. Features. The same is true for other GIS and VR software. Fortunately, we have a solution that combines the advantages of both sides to solve urban design technical problems. This is why ESRI commissioned Multigen-Paradigm to develop an ArcGIS extension, SiteBiulder, which enables ArcGIS to have real-time animation capabilities and accept Multigen's 3D models. So we have a virtual reality system based on GIS and VR applied to urban design.
2.2 System application steps. The complete application of the system includes the planning and design of the scene, the single architectural design, three-dimensional modeling and mapping, real-time virtual animation, part of the content 2.2.1 urban planning and design. Whether it is the development of a new urban area or the reconstruction of an old city, it is necessary to first determine the planning and design goals, and put forward social, economic and environmental requirements. According to the requirements, a series of basic analysis such as natural conditions and construction conditions are carried out. On the basis of analysis, the planning and design plans for land use, road traffic, building layout, vertical planning, and engineering facilities will be completed. It is worth noting that the previous planning and design only used CAD for auxiliary design. This system emphasizes the application of ArcGIS technology to assist in planning and design for two reasons. First, CAD does not have the required spatial analysis capabilities; second, only ArcGIS themes and features (objects) in the theme can be introduced into SiteBiulder for real-time animation. Figure 5 shows the topographic map of the new campus of Hunan City College, which is produced by ArcGIS. Figure 6 shows a planning model of the new campus.
2.2.2 Architectural design. Based on the planning layout, the architectural design plan is carried out. The design results of each monomer are still based on flat, vertical and sectional drawings. In order to cooperate with the next stage of Creator 3D modeling and texture mapping, the single facade renderings drawn by the architect are useful. The entire shaded color elevation map can replace the cumbersome texture of multiple pieces, and has a considerable three-dimensional effect in the three-dimensional scene. If necessary, some of the individual units can be designed for use in virtual alternatives.
2.2.3 Organize ArcGIS topics. In the SiteBiulder 3D scene, each virtual object is organized and introduced as an ArcGIS theme. The three-dimensional scenes are mainly three-dimensional terrain, roads, buildings, trees, paving and grass. The features in the theme do not represent the specific geometry of the object, but only the specific location of each object. For example, a point theme is used to represent the layout of the building. Each building requires only one point to represent. The model of the building represented by each point is stored in the database. The same building, such as a house, only needs to save one instance. As long as the association between the starting point object and the building instance is established, different building models are introduced into the scene.
2.2.4 Create a 3D model. This virtual system uses MultiGen's Creator as a 3D scene modeling tool, and its Open-Flight uses a tree hierarchy to organize and manage scene data. The models in the site involved in urban design include sky, ground, single buildings, structures, trees, street furnishings, billboards, etc., and the modeling workload is huge. Therefore, before establishing the model, the hierarchical attribution of all the individual models in the virtual scene should be determined according to the geometric spatial position of each entity in the scene and the relationship between the model and the model, so as to facilitate the modification and invocation of the model. The 3D model is not as fine as possible. We need to achieve some kind of coordination between geometric reality and texture reality. Properly dividing the geometric faces and preparing the appropriate resolution of the picture is the key to architectural virtuality.
Previous page next page
Stainless Steel Rod Bar,Stainless Steel Round Rod,201 Stainless Steel Bar,202 Stainless Steel Bar
Shandong Xinsuju Steel Co.,Ltd. , https://www.sawlpipe.com