Analyze viewshed (geoprocessing)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 // Copyright 2016 Esri. // // Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. // You may obtain a copy of the License at: http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific // language governing permissions and limitations under the License.  using Esri.ArcGISRuntime.Data; using Esri.ArcGISRuntime.Geometry; using Esri.ArcGISRuntime.Mapping; using Esri.ArcGISRuntime.Symbology; using Esri.ArcGISRuntime.Tasks; using Esri.ArcGISRuntime.Tasks.Geoprocessing; using Esri.ArcGISRuntime.UI; using Esri.ArcGISRuntime.UI.Controls; using System; using System.Collections.Generic; using System.Drawing; using System.Threading.Tasks; using System.Windows;  namespace ArcGIS.WPF.Samples.AnalyzeViewshed {  [ArcGIS.Samples.Shared.Attributes.Sample(  name: "Analyze viewshed (geoprocessing)",  category: "Geoprocessing",  description: "Calculate a viewshed using a geoprocessing service, in this case showing what parts of a landscape are visible from points on mountainous terrain.",  instructions: "Click the map to see all areas visible from that point within a 15km radius. Clicking on an elevated area will highlight a larger part of the surrounding landscape. It may take a few seconds for the task to run and send back the results.",  tags: new[] { "geoprocessing", "heat map", "heatmap", "viewshed" })]  public partial class AnalyzeViewshed  {  // Url for the geoprocessing service.  private const string _viewshedUrl =  "https://sampleserver6.arcgisonline.com/arcgis/rest/services/Elevation/ESRI_Elevation_World/GPServer/Viewshed";   // Used to store state of the geoprocessing task.  private bool _isExecutingGeoprocessing;   // The graphics overlay to show where the user clicked in the map.  private GraphicsOverlay _inputOverlay;   // The graphics overlay to display the result of the viewshed analysis.  private GraphicsOverlay _resultOverlay;   public AnalyzeViewshed()  {  InitializeComponent();   // Create the UI, setup the control references and execute initialization.  Initialize();  }   private void Initialize()  {  // Create a map with topographic basemap and an initial location.  Map myMap = new Map(BasemapStyle.ArcGISTopographic);  myMap.InitialViewpoint = new Viewpoint(45.3790902612337, 6.84905317262762, 70000);   // Hook into the tapped event.  MyMapView.GeoViewTapped += OnMapViewTapped;   // Create empty overlays for the user clicked location and the results of the viewshed analysis.  CreateOverlays();   // Assign the map to the MapView.  MyMapView.Map = myMap;  }   private async void OnMapViewTapped(object sender, GeoViewInputEventArgs e)  {  // The geoprocessing task is still executing, don't do anything else (i.e. respond to  // more user taps) until the processing is complete.  if (_isExecutingGeoprocessing)  {  return;  }   // Indicate that the geoprocessing is running.  SetBusy();   // Clear previous user click location and the viewshed geoprocessing task results.  _inputOverlay.Graphics.Clear();  _resultOverlay.Graphics.Clear();   // Get the tapped point.  MapPoint geometry = e.Location;   // Create a marker graphic where the user clicked on the map and add it to the existing graphics overlay.  Graphic myInputGraphic = new Graphic(geometry);  _inputOverlay.Graphics.Add(myInputGraphic);   // Normalize the geometry if wrap-around is enabled.  // This is necessary because of how wrapped-around map coordinates are handled by Runtime.  // Without this step, the task may fail because wrapped-around coordinates are out of bounds.  if (MyMapView.IsWrapAroundEnabled) { geometry = (MapPoint)geometry.NormalizeCentralMeridian(); }   try  {  // Execute the geoprocessing task using the user click location.  await CalculateViewshed(geometry);  }  catch (Exception ex)  {  MessageBox.Show(ex.ToString(), "Error");  }  }   private async Task CalculateViewshed(MapPoint location)  {  // This function will define a new geoprocessing task that performs a custom viewshed analysis based upon a  // user click on the map and then display the results back as a polygon fill graphics overlay. If there  // is a problem with the execution of the geoprocessing task an error message will be displayed.   // Create new geoprocessing task using the url defined in the member variables section.  GeoprocessingTask myViewshedTask = await GeoprocessingTask.CreateAsync(new Uri(_viewshedUrl));   // Create a new feature collection table based upon point geometries using the current map view spatial reference.  FeatureCollectionTable myInputFeatures = new FeatureCollectionTable(new List<Field>(), GeometryType.Point, MyMapView.SpatialReference);   // Create a new feature from the feature collection table. It will not have a coordinate location (x,y) yet.  Feature myInputFeature = myInputFeatures.CreateFeature();   // Assign a physical location to the new point feature based upon where the user clicked in the map view.  myInputFeature.Geometry = location;   // Add the new feature with (x,y) location to the feature collection table.  await myInputFeatures.AddFeatureAsync(myInputFeature);   // Create the parameters that are passed to the used geoprocessing task.  // Since the service used is only configured for the execute endpoint, construct the parameters using GeoprocessingExecutionType.SynchronousExecute.  GeoprocessingParameters myViewshedParameters =  new GeoprocessingParameters(GeoprocessingExecutionType.SynchronousExecute)  {  // Request the output features to use the same SpatialReference as the map view.  OutputSpatialReference = MyMapView.SpatialReference  };   // Add an input location to the geoprocessing parameters.  myViewshedParameters.Inputs.Add("Input_Observation_Point", new GeoprocessingFeatures(myInputFeatures));   // Create the job that handles the communication between the application and the geoprocessing task.  GeoprocessingJob myViewshedJob = myViewshedTask.CreateJob(myViewshedParameters);   try  {  // Execute analysis and wait for the results.  GeoprocessingResult myAnalysisResult = await myViewshedJob.GetResultAsync();   // Get the results from the outputs.  GeoprocessingFeatures myViewshedResultFeatures = (GeoprocessingFeatures)myAnalysisResult.Outputs["Viewshed_Result"];   // Add all the results as a graphics to the map.  IFeatureSet myViewshedAreas = myViewshedResultFeatures.Features;  foreach (Feature myFeature in myViewshedAreas)  {  _resultOverlay.Graphics.Add(new Graphic(myFeature.Geometry));  }  }  catch (Exception ex)  {  // Display an error message if there is a problem.  if (myViewshedJob.Status == JobStatus.Failed && myViewshedJob.Error != null)  MessageBox.Show("Executing geoprocessing failed. " + myViewshedJob.Error.Message, "Geoprocessing error");  else  MessageBox.Show("An error occurred. " + ex.ToString(), "Sample error");  }  finally  {  // Indicate that the geoprocessing is not running.  SetBusy(false);  }  }   private void CreateOverlays()  {  // This function will create the overlays that show the user clicked location and the results of the  // viewshed analysis. Note: the overlays will not be populated with any graphics at this point.   // Create renderer for input graphic. Set the size and color properties for the simple renderer.  SimpleRenderer myInputRenderer = new SimpleRenderer()  {  Symbol = new SimpleMarkerSymbol()  {  Size = 15,  Color = Color.Red  }  };   // Create overlay to where input graphic is shown.  _inputOverlay = new GraphicsOverlay()  {  Renderer = myInputRenderer  };   // Create fill renderer for output of the viewshed analysis. Set the color property of the simple renderer.  SimpleRenderer myResultRenderer = new SimpleRenderer()  {  Symbol = new SimpleFillSymbol()  {  Color = Color.FromArgb(100, 226, 119, 40)  }  };   // Create overlay to where viewshed analysis graphic is shown.  _resultOverlay = new GraphicsOverlay()  {  Renderer = myResultRenderer  };   // Add the created overlays to the MapView.  MyMapView.GraphicsOverlays.Add(_inputOverlay);  MyMapView.GraphicsOverlays.Add(_resultOverlay);  }   private void SetBusy(bool isBusy = true)  {  // This function toggles the visibility of the 'BusyOverlay' Grid control defined in xaml,  // sets the 'progress' control feedback status and updates the _isExecutingGeoprocessing  // boolean to denote if the viewshed analysis is executing as a result of the user click  // on the map.   if (isBusy)  {  // Change UI to indicate that the geoprocessing is running.  _isExecutingGeoprocessing = true;  BusyOverlay.Visibility = Visibility.Visible;  Progress.IsIndeterminate = true;  }  else  {  // Change UI to indicate that the geoprocessing is not running.  _isExecutingGeoprocessing = false;  BusyOverlay.Visibility = Visibility.Collapsed;  Progress.IsIndeterminate = false;  }  }  } }