GIS 5100 - Visibility Analysis

For module 3 we continued learning about LiDAR data and analysis with the introduction of visibility analysis. The visibility analysis introduced included Line of Sight (LOS) analysis and View Shed analysis. The lab assignment supplemented the lectures by requiring the completion of four exercises. The following are the exercises and a bit of information about each: 

Exercise 1: Introduction to 3D Visualization

As the title suggests, this exercise introduced students to 3D visualizations. It began highlighting how 3D can be used and quickly moved into providing hands on experience in displaying and navigating 3D data in ArcGIS Pro, displaying 2D layers as 3D by extruding the 2D feature, and applying effects to the 3D data such as various types of illumination. 

Exercise 2: Performing Line of Sight Analysis

According to ESRI, line of sight analysis determines if two points in space are intervisible. Intervisibility can be impacted by and obstruction, such as a building, which inhibits the line of sight at the point of obstruction. Exercise 2 allowed us to learn how to determine intervisibility using geoprocessing tools to, first, construct sight lines followed by using the line of sight tool. This then opened up further analysis capabilities, such as calculating view distance and determining visibility distance. 

Exercise 3: Performing Viewshed Analysis in ArcGIS Pro

While line of sight analysis considers only a line or group of lines, view shed analysis considers the visibility of an area. This exercise used surface elevation (raster/DEM/DSM etc) to determine which areas are visible from a view point or multiple view points by using the viewshed geoprocessing tool. We also used raster functions to assist in determining coverage. 

Exercise 4: Sharing 3D Content Using Scene Layer Packages

As with most geospatial data, it is important to have the ability to share 3D content. This type of data can be large in size and require a great amount of processing. As such, learning to share it using Scene Layer Packages is not only useful but quite easy. Once a 3D scene is authored it can be saved as a scene layer package and added online for viewing  by uploading the scene layer package and publishing it. The uploading and publishing process is user friendly, as is the viewing for the end user. I've included a couple images from the scene viewer below. It is important to note, however, that being able to upload and publish data requires access to an organizational account and publishing rights/capabilities. 

Overview of the Area of Interest in Scene Viewer

A view from the water's edge of the Area of Interest in Scene Viewer



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