/// <summary>
/// Updates all Dijkstra Routes
/// </summary>
public void UpdateAllStarts()
{
startingPoints = new List <DijkstraStart>();
foreach (Location l in reachableLocations)
{
DijkstraStart temp = createDijkstraStart(l, false);
startingPoints.Add(temp);
}
}
/// <summary>
/// Update all Dijkstra routes that have startLocation as starting point
/// </summary>
/// <param name="startLocation"></param>
public void UpdateSingleStart(Location startLocation)
{
DijkstraStart result = null;
if (reachableLocations.Contains(startLocation))
{
foreach (DijkstraStart ds in startingPoints)
{
if (ds.StartPoint == startLocation)
{
result = ds;
}
}
if (result != null)
{
startingPoints.Remove(result);
}
DijkstraStart temp = createDijkstraStart(startLocation, false);
startingPoints.Add(temp);
}
}
private DijkstraStart createDijkstraStart(Location startLocation, bool animate) //main methods for creating shortest routes accros the map
{
if (!reachableLocations.Contains(startLocation))
{
throw new Exception("Unknown location detected");
}
List <Road> currentRoads = new List <Road>(); //considered roads at the moment
List <int> currentRoadsLenghts = new List <int>(); //road lenghts
DijkstraStart dijkstraStart = new DijkstraStart(startLocation);
currentRoads = getRoadsConnectedToLocation(startLocation);
foreach (Road r in currentRoads)
{
currentRoadsLenghts.Add(r.InitialCost);
}
int lowestIndex;
Road currentRoad;
int currentRoadLenght;
Location prevLocation = null;
Location newLocation = null;
//ANIMATION
if (animate)
{
// resets all roads to black color
foreach (Road r in allRoads)
{
r.ResetDrawFields();
}
}
while (currentRoads.Count != 0)
{
//get next shortest route
lowestIndex = findLowestIndex(currentRoadsLenghts);
currentRoad = currentRoads[lowestIndex];
currentRoadLenght = currentRoadsLenghts[lowestIndex];
//ANIMATION
if (animate)
{
// colors the potential roads with yellow
foreach (Road r in currentRoads)
{
r.LineColor = Color.Yellow;
}
Map.RedrawMapNow();
// makes the system wait 2 seconds
System.Threading.Thread.Sleep(1000);
// after it colors all potential yellow it colors the best green.
currentRoad.LineColor = Color.Green;
}
//claim new shortest route
if (dijkstraStart.isConnectedToLocation(currentRoad.Vertex1))
{
prevLocation = currentRoad.Vertex1;
}
else
{
newLocation = currentRoad.Vertex1;
}
if (dijkstraStart.isConnectedToLocation(currentRoad.Vertex2))
{
prevLocation = currentRoad.Vertex2;
}
else
{
newLocation = currentRoad.Vertex2;
}
if (prevLocation == null)
{
throw new NullReferenceException();
}
if (newLocation == null)
{
throw new NullReferenceException();
}
DijkstraRoute previousDijkstraRoute = dijkstraStart.GetRouteTo(prevLocation);
List <Road> newRoute;
//makes a copy of the current route and adds the current road
if (previousDijkstraRoute != null)
{
newRoute = previousDijkstraRoute.CopyRoute();
newRoute.Add(currentRoad);
}
else
{
// makes a new route and adds the road to it
newRoute = new List <Road>();
newRoute.Add(currentRoad);
}
DijkstraRoute newDijkstraRoute = new DijkstraRoute(newRoute, newLocation);
dijkstraStart.AddNewRoute(newDijkstraRoute);
//Determine new roads and remove currentRoad/exsiting roads
currentRoads.RemoveAt(lowestIndex);
currentRoadsLenghts.RemoveAt(lowestIndex);
List <Road> newAddingRoads = getRoadsConnectedToLocation(newLocation);
newAddingRoads.Remove(currentRoad);
//filter out already existing roads in currentRoads
for (int i = 0; i < newAddingRoads.Count; i++)
{
if (dijkstraStart.isConnectedToLocation(newAddingRoads[i].Vertex1) &&
dijkstraStart.isConnectedToLocation(newAddingRoads[i].Vertex2))
{
if (currentRoads.Contains(newAddingRoads[i]))
{
int index = currentRoads.IndexOf(newAddingRoads[i]);
currentRoads.RemoveAt(index);
currentRoadsLenghts.RemoveAt(index);
}
newAddingRoads.RemoveAt(i);
i--;
}
}
//Adding new roads and calculating new roads lenghts
foreach (Road r in newAddingRoads)
{
int roadLenght = r.InitialCost + currentRoadLenght;
currentRoads.Add(r);
currentRoadsLenghts.Add(roadLenght);
}
//reseting values
currentRoad = null;
prevLocation = null;
newLocation = null;
currentRoadLenght = -1;
lowestIndex = -1;
}
if (!animate)
{
return(dijkstraStart);
}
else
{
Map.RedrawMap();
}
return(null);
}
