Research On 3D Scene Modeling Method Of Residential Area Based On Construction Or As-built Data

Digital City plays an increasingly important role in integrating various urban geographic information resources and intelligently serving the city's management and decision-making,many cities in China have started the construction of digital cities gradually.With the proposal of "Real-scene 3D China Construction",Digital City and Smart City put forward higher requirements for modeling efficiency,quality of models and expression of indoor and outdoor integration of 3D city model.Residential area is basic space unit of the city,therefore building the three-dimensional scene model of which is a good support for the development of digital city.In the current modeling methods of three-dimensional residential area,modern mapping technology such as photogrammetry and laser scanning has high modeling efficiency,but the modelling result lacks the information support such as various entity objects' semantics and attributes;the artificial interaction modeling has high cost and long period;Modeling based on construction or as-built data affects modeling efficiency due to complex information.However,construction or as-built data with rich semantics,geometry,attributes and other information are not available in other modeling methods,How to effectively organize rich information in construction or as-built data and improve the efficiency of 3D modeling is the key.This paper setting out from the perspective of Geographic Scenario and taking construction or as-built data as the data source,attempts to propose a method that can builds three-dimensional scene model of residential area quickly and minimizes human operation.The main research contents and achievements include:(1)From the perspective of Geographic Scenario,this paper analyzed the organizational form of design elements in construction or as-built data by means of geographical information expression elements,including entity geometry,auxiliary design and description,extracted the scene element such as characters,things and time form the design elements,and established a cognitive framework from 2D drawings to 3D scenes.(2)Aiming at the existing errors about topology geometry including intersecting and non-closing between the entity geometry,this paper proposed an inspection and correction method to automatically solve the problem,ensuring that parcel polygons extracted have no gaps or overlapping between each other.Simultaneously,this paper organized relevant knowledge rules by sorting out relevant national standards and industry norms to assist in the automatic identification of different types of land use.(3)Based on a small number of terrain design elements in the drawings,the automatic elevation data extraction method and micro terrain modeling method were proposed by this paper.The modeling results are based on different types of land use,and the terrain can be well integrated into the scene.(4)According to the CGA(Computer Generated Architecture)rules,this paper combined entities based on the results of micro terrain modeling in residential area with the component grade building monomer and building pipe network,realizing the 3D scene model of indoor and outdoor integration.Finally,the modeling results are published as a 3D scene service,which if effectively combined with the 2D map.Through the experiment and the combination with the actual project,the results show that the method proposed by this paper about building 3D scene model based on construction and as-built data can effectively organize the rich information effectively to improve the automation degree of some modelling links,and the mothed has certain superiority in efficiency.At the same time,the modeling results,that is the combination of topographic elements and component grade building monomer and building pipe network,can meet the needs of a variety of application analysis,which is a good supplement to the development of digital city.