To present a 3D scene of University Park Campus, you need an elevation base for your building footprints and other layers such as roads and trees. In this section, we focus on preparing the Digital Elevation Model (DEM) for University Park Campus. The Digital Elevation Model (DEM) is a bare earth elevation model. It has been extracted from LiDAR data.
In the previous section, you worked with feature data, data displayed as discrete objects, or features. While feature data is great for depicting buildings, roads, or trees, it is not the best way to depict elevation over a continuous surface. To do that, you'll use raster data, which can demonstrate a continuous surface. Raster data is composed of pixels, each with its own value. Although it looks different from feature data, you add it to the map in the same way.
The pop-up shows the Pixel Value, which indicates the actual value of a pixel. In this raster, it shows the elevation. In the above image, the selected pixel has an elevation of about 1159 feet above sea level.
Before exploring the raster data in 3D, we need to smooth the elevation model, so the 3D model of campus fits the elevation model nicely. In order to monitor the level of smoothness of a DEM, creating contours can be helpful. A contour set built based on a raw digital elevation model (DEM) data can show minor variations and irregularities in the data. Creating a smooth contour set for topography is helpful in smoothing the data.
Note: the smooth grid should not be used for any analysis that requires raw DEM. For instance, building height cannot be extracted from a smoothed DEM.
The Focal Statistics tool will resample from the DEM and apply a search distance defined by cells or model distance.
Click the contour layer in the contents pane. Make sure the symbol is highlighted by clicking on it. From the top ribbon, under Feature Layer, click Labeling. Under Label Class group, choose Contour for Field value. For class value click on the SQL button.