This sample demonstrates how to create a location viewshed from a camera.
How it works
The viewshed analysis object is created using the initializer of the AGSLocationViewshed called init(camera:minDistance:maxDistance).
The sample starts with a viewshed created from the initial camera location. The output is displayed in an overlay representing the visible areas in green color and non-visible areas in red color. This is achieved by creating an AGSAnalysisOverlay for the viewshed and adding that overlay to a collection of analysis overlays in AGSSceneView.
When user clicks the button called Update from camera, the viewshed is updated with the current camera by calling the update(from:) method on AGSLocationViewshed. The current camera position is retrieved from the currentViewpointCamera() method on AGSSceneView.