/// <summary>
/// Calculate the visual magintude from a viewpoint.
/// </summary>
/// <param name="viewpoint">Viewpoint</param>
/// <param name="losMap">LOS map</param>
private void CalculateVisualMagnitude(SpatialUtils.ViewpointProps viewpoint, GeoMap losMap)
{
double visualMagnitude;
spatialUtils.Viewpoint = viewpoint;
viewpoint.Elevation = elevationMap[viewpoint.Y, viewpoint.X] + viewpoint.ElevationOffset;
losMap[viewpoint.Y, viewpoint.X] = GeoMap.UndefinedValue; //initialize LOS of the viewpoint
//find out the maximum distance to the edge of map
int maxDistance = GetMaximumDistance(viewpoint);
for (int i = 1 + omittedRings; i < maxDistance; i++)
{
GeoMap.Ring ring = elevationMap.GetRing(viewpoint.Y, viewpoint.X, i);
foreach (int[] item in ring)
{
if (spatialUtils.IsCellVisible(losMap, item[0], item[1]))
{
visualMagnitude = spatialUtils.GetVisualMagnitude(item[0], item[1]);
if (visualMagnitude > 0)
{
sumator.AddResult(new Sumator.VisualMagnitudeResult()
{
Y = item[0],
X = item[1],
VisualMagnitude = visualMagnitude,
Weight = viewpoint.Weight
});
}
}
}
}
}
/// <summary>
/// Contructor to initialize the worker.
/// </summary>
/// <param name="workQueue">Work queue share amon workers.</param>
/// <param name="elevationMap">Elevation map</param>
/// <param name="sumator">Sumator instance</param>
/// <param name="parent">Work manager</param>
public VisualMagnitudeWorker(ref ConcurrentQueue <SpatialUtils.ViewpointProps> workQueue, ref GeoMap elevationMap, ref Sumator sumator, WorkManager parent)
{
spatialUtils = new SpatialUtils(ref elevationMap);
this.workQueue = workQueue;
this.elevationMap = elevationMap;
this.sumator = sumator;
this.parent = parent;
}
/// <summary>
/// Start processing the work queue.
/// </summary>
public void Start()
{
GeoMap losMap = new GeoMap(elevationMap.GetLength(0), elevationMap.GetLength(1));
while (workQueue.TryDequeue(out SpatialUtils.ViewpointProps viewpoint))
{
System.Diagnostics.Debug.WriteLine(workQueue.Count + " left");
CalculateVisualMagnitude(viewpoint, losMap);
}
System.Diagnostics.Debug.WriteLine("ThreadDone");
parent.ThreadFinished();
}
/// <summary>
/// Create a mock map for testing purposes.
/// </summary>
/// <param name="dimensionY">Y length</param>
/// <param name="dimensionX">X length</param>
/// <returns>Mocked GeoMap</returns>
public static GeoMap CreateMock(int dimensionY, int dimensionX)
{
GeoMap map = new GeoMap(dimensionY, dimensionX);
Random rnd = new Random();
for (int y = 0; y < dimensionY; y++)
{
for (int x = 0; x < dimensionX; x++)
{
map[y, x] = y;
}
}
return(map);
}
/// <summary>
/// Start calculationg the visual magnitude.
/// </summary>
/// <param name="elevationMap">Elevation map</param>
public void StartWorking(ref GeoMap elevationMap)
{
sumator = new Sumator(elevationMap.GetLength(0), elevationMap.GetLength(1));
sumator.Start();
startingQueueSize = workQueue.Count;
runningThreads = threadCount;
for (int i = 0; i < threadCount; i++)
{
VisualMagnitudeWorker worker = new VisualMagnitudeWorker(ref workQueue, ref elevationMap, ref sumator, this);
Thread thread = new Thread(worker.Start);
threads[i] = thread;
thread.Start();
}
}
/// <summary>
/// Convert the DEM raster to internal elevation map.
/// </summary>
/// <param name="raster">DEM raster</param>
/// <returns>Elevation map</returns>
private GeoMap CreateElevationMap(Raster raster)
{
PixelBlock currentPixelBlock = raster.CreatePixelBlock(raster.GetWidth(), raster.GetHeight());
raster.Read(0, 0, currentPixelBlock);
Array pixels = currentPixelBlock.GetPixelData(0, false);
GeoMap elevationMap = new GeoMap(raster.GetHeight(), raster.GetWidth());
Tuple <double, double> cellSize = raster.GetMeanCellSize();
/*if (Math.Abs(cellSize.Item1-cellSize.Item2) < cellSize.Item1*0.05) {
* MessageBox.Show("Cells are not squares. Using X size of cells.", "Rectuangular cells", System.Windows.MessageBoxButton.OK, System.Windows.MessageBoxImage.Information);
* }*/
elevationMap.CellSize = cellSize.Item1;
elevationMap.ImportData(pixels);
return(elevationMap);
}
/// <summary>
/// Determine if the cell is visible from the viewpoint. All cells in LOS cell-viewpoint have to be previously calculated and present in LOS map.
/// </summary>
/// <param name="losMap">Map which contains LOS values of the cells</param>
/// <param name="cellY">Y coordinate of the cell</param>
/// <param name="cellX">X coordinate of the cell</param>
/// <returns></returns>
public bool IsCellVisible(GeoMap losMap, int cellY, int cellX)
{
Orientation cellOrientation = GetCellOrientation(cellY, cellX);
GetNeighborCells(cellY, cellX, cellOrientation, out int adjacentY, out int adjacentX, out int offsetY, out int offsetX);
double adjacentWeight = InterpolateWeight(cellY, cellX, cellOrientation);
double viewingLos = GetViewingSlope(cellY, cellX);
double cellLos = losMap[adjacentY, adjacentX] * adjacentWeight + losMap[offsetY, offsetX] * (1 - adjacentWeight);
if (viewingLos > cellLos)
{
losMap[cellY, cellX] = cellLos;
return(false);
}
else
{
losMap[cellY, cellX] = viewingLos;
return(true);
}
}
/// <summary>
/// Constructor. Initialize the class with an elevation map.
/// </summary>
/// <param name="elevationMap">Elevtion map</param>
public SpatialUtils(ref GeoMap elevationMap)
{
cellResolution = elevationMap.CellSize;
ElevationMap = elevationMap;
}
/// <summary>
/// Asynchrnously start the visual magnitude analysis.
/// </summary>
public async void StartAnalysis()
{
if (!ValidateInputLayers())
{
return;
}
outputFolder = CreateOutputDirectory(outputFolderName);
if (File.Exists(outputFolder + "/" + SettingsManager.Instance.CurrentSettings.OutputFilename))
{
System.Windows.MessageBoxResult messageResult = MessageBox.Show("The output file already exists and will be overwritten. Continue?", "File exists!", System.Windows.MessageBoxButton.OKCancel, System.Windows.MessageBoxImage.Warning);
if (messageResult == System.Windows.MessageBoxResult.OK)
{
GarbageHelper.Instance.AddGarbage(outputFolder + "/" + SettingsManager.Instance.CurrentSettings.OutputFilename);
GarbageHelper.Instance.CleanUp();
}
else
{
return;
}
}
if (File.Exists(outputFolder + "/" + tmpRasterName))
{
GarbageHelper.Instance.AddGarbage(outputFolder + "/" + tmpRasterName);
GarbageHelper.Instance.CleanUp();
}
///most tasks have to run on MCT thread
await QueuedTask.Run(async() => {
outputFolder = CreateOutputDirectory(outputFolderName);
FileSystemDatastore outputDataStore = CreateNewDatastore();
//get viewpoints
Raster raster = SettingsManager.Instance.SelectedDemLayer.GetRaster();
Projection projection = new Projection(raster, outputFolder); //make the detection automatic
try {
if (await projection.CalculateViewpoints(SettingsManager.Instance.SelectedViewpointLayer) == false)
{
MessageBox.Show("Invalid viewpoint layer type.\nOnly points, lines and polylines are supported.", "Error", System.Windows.MessageBoxButton.OK, System.Windows.MessageBoxImage.Error);
return;
}
} catch (Exception) {
if (!SettingsManager.Instance.CurrentSettings.OffsetGlobal)
{
MessageBox.Show("Invalid viewpoint data. Do the viewpoints have OFFSET column specified?", "Error", System.Windows.MessageBoxButton.OK, System.Windows.MessageBoxImage.Error);
}
else if (SettingsManager.Instance.CurrentSettings.WeightedViewpoints)
{
MessageBox.Show("Invalid viewpoint data. Do the viewpoints have WEIGHT column specified?", "Error", System.Windows.MessageBoxButton.OK, System.Windows.MessageBoxImage.Error);
}
else
{
MessageBox.Show("Invalid viewpoint data.", "Error", System.Windows.MessageBoxButton.OK, System.Windows.MessageBoxImage.Error);
}
return;
}
GeoMap elevationMap = CreateElevationMap(raster);
//initialize work manager
WorkManager workManager = new WorkManager(SettingsManager.Instance.CurrentSettings.WorkerThreads);
int invalidViewpointsCount = 0;
foreach (SpatialUtils.ViewpointProps viewpoint in projection)
{
if (viewpoint.Y < 0 || viewpoint.X < 0)
{
invalidViewpointsCount++;
}
else
{
if (SettingsManager.Instance.CurrentSettings.OffsetGlobal)
{
viewpoint.ElevationOffset = SettingsManager.Instance.CurrentSettings.AltOffset;
}
workManager.AddWork(viewpoint);
}
}
if (invalidViewpointsCount > 0)
{
string message = invalidViewpointsCount.ToString()
+ (invalidViewpointsCount == 1
? " viewpoint was invalid or failed to process."
: " viewpoints were invalid or failed to process.");
MessageBox.Show(message, "Ignored viewpoints", System.Windows.MessageBoxButton.OK, System.Windows.MessageBoxImage.Warning);
}
//wait for the calculation of the visual magnitude for all viewpoints to finish
var watch = System.Diagnostics.Stopwatch.StartNew();
workManager.StartWorking(ref elevationMap);
WorkManager.AutoEvent.WaitOne();
GeoMap result = workManager.GetResult();
MessageBox.Show("Computation finished\n------------\nTime: " + watch.ElapsedMilliseconds / 1000 + " seconds\nViewpoints: " + projection.GetViewpointsCount(), "Finished", System.Windows.MessageBoxButton.OK, System.Windows.MessageBoxImage.Information);
//save and display the result
try {
WriteToRaster(raster, outputDataStore, result);
} catch (Exception) {
MessageBox.Show("Cannot write data to raster.", "Error", System.Windows.MessageBoxButton.OK, System.Windows.MessageBoxImage.Error);
}
LayerFactory.Instance.CreateLayer(new Uri(Path.Combine(outputFolder, SettingsManager.Instance.CurrentSettings.OutputFilename)),
MapView.Active.Map);
//clean up temporary files
GarbageHelper.Instance.CleanUp();
});
}
/// <summary>
/// Write results to a rester.
/// </summary>
/// <param name="raster">DEM raster</param>
/// <param name="outputDataStore">Output datastore</param>
/// <param name="result">Elevation map with resuluts</param>
private void WriteToRaster(Raster raster, FileSystemDatastore outputDataStore, GeoMap result)
{
raster.SetNoDataValue(0);
raster.SetPixelType(RasterPixelType.DOUBLE);
RasterDataset resultRasterDataset = raster.SaveAs(tmpRasterName, outputDataStore, rasterFormat);
GarbageHelper.Instance.AddGarbage(Path.Combine(outputFolder, tmpRasterName));
Raster resultRaster = resultRasterDataset.CreateRaster(new int[1] {
0
});
resultRaster.Refresh();
if (!resultRaster.CanEdit())
{
MessageBox.Show("Cannot write to raster", "Error", System.Windows.MessageBoxButton.OK, System.Windows.MessageBoxImage.Error);
return;
}
PixelBlock pixelBlock = resultRaster.CreatePixelBlock(resultRaster.GetWidth(), resultRaster.GetHeight());
resultRaster.Read(0, 0, pixelBlock);
pixelBlock.Clear(0);
Array pixel = new double[resultRaster.GetWidth(), resultRaster.GetHeight()];
pixelBlock.SetPixelData(0, result.Transpose());
resultRaster.Write(0, 0, pixelBlock);
resultRaster.Refresh();
resultRaster.SaveAs(SettingsManager.Instance.CurrentSettings.OutputFilename, outputDataStore, rasterFormat);
}
/// <summary>
/// Constructor.
/// </summary>
/// <param name="dimensionY">Y size of the map</param>
/// <param name="dimensionX">X size of the map</param>
public Sumator(int dimensionY, int dimensionX)
{
VisualMagnitudeMap = new GeoMap(dimensionY, dimensionX);
VisualMagnitudeMap.Initialize();
}