This paper presents a systematic GIS-based methodology to obtain the shadow cast profile of a group of buildings on arbitrarily orientated and tilted surfaces. The model is integrated in the widely-employed 2D-GIS environment. Given its scalability, the methodology can be easily applied from a local level up to a district, city or even regional level. This work is of interest for a wide range of applications such as for instance in Solar Resource Assessments (SRA) in urban environments.

The starting point is to use cadastral cartography and LiDAR altimetric data to obtain a 3D vector-based model of the buildings using high robust mode estimators. Once the geometry of the buildings is defined, analytical models are applied to calculate the shadow cast profile on any arbitrarily orientated and tilted surface of the surroundings.

The model has been implemented in the R programming language. An extensive validation has been carried out for several buildings of Valencia (Spain) using CAD elevation views of the buildings and the SketchUp’s shadow tool. The error of the vector-based city model is lower than 1% in all LiDAR datasets. The maximum error of the overall methodology, including both height and shadow models, is lower than 2%.

本文提出了一种基于GIS的系统方法，以获取任意定向和倾斜表面上的一组建筑物的阴影投射轮廓。该模型已集成到广泛使用的2D-GIS环境中。鉴于其可扩展性，该方法可以轻松地从本地级别到地区，城市甚至地区级别应用。这项工作对于广泛的应用是有意义的，例如在城市环境中的太阳能资源评估（SRA）中。

起点是使用地籍制图法和LiDAR测高数据，以使用高鲁棒性模式估计器获得基于3D矢量的建筑物模型。定义建筑物的几何形状后，将应用分析模型来计算在环境中任意定向和倾斜的表面上的阴影投射轮廓。

该模型已用R编程语言实现。使用建筑物的CAD高程图和SketchUp的阴影工具，对瓦伦西亚（西班牙）的几座建筑物进行了广泛的验证。在所有LiDAR数据集中，基于矢量的城市模型的误差均低于1％。包括高度和阴影模型在内的整个方法的最大误差均低于2％。