National database of 3D buildings

This dataset contains the 3D and 2D buildings on the national territory of the Grand Duchy of Luxembourg in 2020. (NB: to obtain data on the municipal territory of the City of Luxembourg, please contact the topography and geomatics department of the municipal administration of the VDL https://pars.vdl.lu/fr/la-ville/les-services-a-votre-ecoute/service-topographie-et-geomatique) ### 3D buildings (LOD 2.2) **Modeling** The 3D buildings were made on the basis of the aerial shots of summer 2020 (flight period: end of July, early August and mid-September 2020; flight height: ± 3 500 m above ground) by photogrammetric rendering of roofs (EMQ in x, y and z ≤ 20 cm), followed by downward extrusion and texturing of the resulting 3D models of buildings with oblique shooting. Only the roofs of buildings with a footprint greater than 20 m² have been seized, taking into account superstructures (e.g., sitting dogs) with the longest side exceeding 50 cm and which are larger than 1 m³. **Data structure and availability** The 3D buildings correspond to the LOD (Level of Detail) 2.2 classification and are available in CityGML format. The data are grouped in a compressed file (zip) per commune, including the textures of the buildings in jpg and a CityGML file consisting of the objects “building”, “roof(s)”, “wall(s)” and “building, roof, wall, ground surface) of all the buildings of the municipality. Each object has a unique identifier allowing identification with the building to which it belongs. In addition, a geodatabase file database is made available with all 3D models in the form of multipatch entities (grounds, roofs, solids, walls). ### 2D buildings 2D buildings consist of the ground right-of-way of 3D buildings, thus the stretch of their roofs. They are made available in a shapefile or geojson file.本数据集包含2020年卢森堡大公国国土范围内的二维与三维建筑数据。 （注：若需获取卢森堡市市级辖区范围内的数据，请联系卢森堡市市政管理局地形与测绘部门，网址：https://pars.vdl.lu/fr/la-ville/les-services-a-votre-ecoute/service-topographie-et-geomatique） ### 三维建筑（细节层次2.2，LOD 2.2） **建模流程** 本次三维建筑模型基于2020年夏季的航空影像（飞行时段：2020年7月末、8月初及9月中旬；飞行高度：距地面±3500米），通过摄影测量方法对屋顶进行建模（采用EMQ标准，x、y、z三方向测量精度均≤20厘米），随后通过倾斜摄影对生成的建筑三维模型进行向下拉伸与纹理映射。 仅采集占地面积大于20平方米的建筑屋顶，同时纳入最长边超过50厘米、体积大于1立方米的附属构筑物（如屋顶凸起类结构，例如烟囱）。 **数据结构与可获取性** 本次三维建筑数据符合细节层次2.2（Level of Detail，LOD 2.2）分类标准，以CityGML格式提供。数据按市镇打包为压缩文件（ZIP格式），其中包含建筑纹理JPG文件，以及涵盖该市镇所有建筑的"building"、"roof(s)"、"wall(s)"及"building, roof, wall, ground surface"对象的CityGML文件。每个对象均配有唯一标识符，可与其所属建筑建立关联。 此外，还提供了地理数据库文件，其中所有三维模型以多面片实体（地面、屋顶、实体、墙体）的形式存储。 ### 二维建筑 二维建筑对应三维建筑的地面权属范围，即其屋顶覆盖的水平区域。数据以Shapefile或GeoJSON格式提供。