![]() The 16-step workflow is organized into four sections: zip file on įigure 2 (left): Add the polygon feature created in ArcMap to Overpass.3dd.įigure 3 (right): By default, the polygon will drape over the globe surface like a blanket. Google SketchUp 8 (free version available at /download/).ArcGIS 10 with the 3D Analyst and Spatial Analyst extensions.To complete this exercise, the following software and data are required Some familiarity with Google SketchUp may also be helpful. It's assumed that the reader is familiar with ArcGIS Desktop applications and the ArcGIS 3D Analyst extension, including ArcGlobe. The workflow outlined will familiarize the reader with tools in ArcGIS 10 for importing, exporting, and placing different types of 3D features. It uses a geometrically simple urban feature-a freeway overpass in downtown Philadelphia-and starts with a polygon and some high-resolution aerial imagery. This exercise walks the reader through the process of creating and adding texture to a 3D multipatch feature. ArcGIS 10 introduces a host of new 3D data management and analysis capabilities that enhance 3D analysis. The multipatch, Esri's native 3D feature type, is a key element whether working in ArcGlobe or ArcScene. The 3D virtual city is emerging as an essential GIS tool for visualization and analysis in the urban environment-from placing a proposed building construction in the context of its surroundings to conducting analyses in three dimensions such as line-of-sight or 3D volumetric shadows. To use fewer cores, use the Parallel Processing Factor environment setting.Figure 1: This exercise shows how to correct this sampling error, commonly seen in high-resolution DEMs in urban environments. The maximum number of cores that can be used is four. For example, you can run the Viewshed tool to calculate the visibility, or use the solar radiation tools to calculate the rooftop solar energy potential for the buildings in an urban environment.īy default, this tool will take advantage of multicore processors. With the resulting elevation raster, you can run other tools that operate on raster data to solve analysis problems in an urban space. Then use the Mosaic tool to mosaic the buildings raster with the DEM raster. To accomplish this, first use this tool to convert the multipatch features to a raster. This tool allows you to use 3D building features (as multipatches) in an urban space to build a digital elevation model (DEM). If the spatial reference of the dataset is different, it will be projected based on the selected Cell Size Projection Method. The cell size of that raster dataset will be used directly in the analysis, provided the spatial reference of the dataset is the same as the output spatial reference. If the cell size has been specified using a raster dataset, the parameter will show the path of the raster dataset instead of the cell size value. If the cell size has been specified using a numeric value, the tool will use it directly for the output raster. If nothing has been specified, the cell size is calculated from the shorter of the width or height of the extent divided by 250, where the extent is in the Output Coordinate System specified in the environment. If neither the parameter cell size nor the environment cell size has been specified, but the environment Snap Raster has been set, the cell size of the snap raster is used. If the cell size hasn’t been explicitly specified as the parameter value, it is derived from the environment Cell Size, if it has been specified. The Output cell size can be defined by a numeric value or obtained from an existing raster dataset. Vertical triangles-essentially vertical walls without a roof-are excluded from the rasterization and will not be represented in the output raster. An output cell will receive a value if the cell center falls within the footprint of one or more input multipatch features otherwise, it will be assigned NoData. The maximum or minimum z-value from the points of intersection is assigned to the output raster. To determine the z-value for each cell, a vertical line is extended from the cell center location to intersect the input multipatch features. The output raster stores the z-values of the input multipatch features at each cell center location.
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