public override void IterateOpenSet()
{
OpenSetIterations++;
//Path doesnt exist if the openset runs out
if (OpenSet.Count <= 0)
{
Log.Print("no path found");
GridManager.Instance.HideAllParentIndicators();
FindingPathway = false;
return;
}
//Take the front node from the open set
Node Current = OpenSet[0];
OpenSet.Remove(Current);
Current.Closed = true;
//Pathway is completed once the end node has been reached
if (Current == PathEnd)
{
Log.Print("Pathway found after " + OpenSetIterations + " iterations.");
FindingPathway = false;
GridManager.Instance.HideAllParentIndicators();
foreach (Node Step in GridManager.Instance.GetCompletedPathway(PathStart, PathEnd))
{
Step.SetType(NodeType.Pathway);
}
return;
}
//Process all the nodes neighbours
foreach (Node Neighbour in GridManager.Instance.GetTraversableNeighbours(Current))
{
//Skip neighbours already searched
if (Neighbour.Closed || Neighbour.Opened)
{
continue;
}
//Move this neighbour onto the open list, open it and update its parent
OpenSet.Add(Neighbour);
Neighbour.Opened = true;
Neighbour.Parent = Current;
Neighbour.ToggleParentIndicator(true);
Neighbour.PointIndicator(Neighbour.GetDirection(Current));
}
}
public override void IterateOpenSet()
{
//Track how many iterations have taken place to find this pathway so far
OpenSetIterations++;
//If the open set is empty, then no pathway was able to be found
if (OpenSet.Count <= 0)
{
//Print a failure message and reset the grid
Log.Print("Unable to find a valid pathway using A* algorithm.");
FindingPathway = false;
GridManager.Instance.HideAllParentIndicators();
return;
}
//Get the cheapest node currently being stored in the open set
Node Current = GridManager.Instance.FindCheapestNode(OpenSet);
OpenSet.Remove(Current);
//When Current matches the end node, the pathway is ready to be reconstructed
if (Current == PathEnd)
{
//Announce the pathway has been found and how long it took to find
Log.Print("A* pathfinding completed after " + OpenSetIterations + " iterations.");
//Hide all parent indicators
GridManager.Instance.HideAllParentIndicators();
//Grab and display the final pathway
List <Node> Pathway = GridManager.Instance.GetCompletedPathway(PathStart, PathEnd);
foreach (Node PathStep in Pathway)
{
PathStep.SetType(NodeType.Pathway);
}
//Finalize the process
FindingPathway = false;
return;
}
//Remove the current node from the open set, then iterate over its neighbours
OpenSet.Remove(Current);
foreach (Node Neighbour in GridManager.Instance.GetTraversableNeighbours(Current))
{
if (Current.GScore < Neighbour.GScore)
{
//Update this as the preferred way to travel
Neighbour.Parent = Current;
Neighbour.ToggleParentIndicator(true);
Neighbour.PointIndicator(Neighbour.GetDirection(Current));
//Update neighbours score values
Neighbour.GScore = Current.GScore;
Neighbour.FScore = Neighbour.GScore + GridManager.FindHeuristic(Neighbour, PathEnd);
//Add neighbour to open set if its not there already
if (!OpenSet.Contains(Neighbour))
{
OpenSet.Add(Neighbour);
}
}
}
}
public override void IterateOpenSet()
{
//Track how many iterations have taken place to find this pathway
OpenSetIterations++;
//Once the openset has been exhausted its time to complete the pathway
if (OpenSet.Count <= 0)
{
//Get the completed pathway
List <Node> Pathway = GridManager.Instance.GetCompletedPathway(PathStart, PathEnd);
//If the path is empty, then no pathway was able to be found between the target nodes
if (Pathway == null)
{
//Print a failure message and reset the grid
Log.Print("Unable to find a valid pathway using Dijkstras algorithm.");
FindingPathway = false;
GridManager.Instance.HideAllParentIndicators();
return;
}
//Announce the pathway has been found
Log.Print("Dijkstras pathfinding completed after " + OpenSetIterations + " iterations.");
//Hide all the neighbour indicators
GridManager.Instance.HideAllParentIndicators();
//Change the type of all nodes in the pathway to display it in the game
foreach (Node PathStep in Pathway)
{
PathStep.SetType(NodeType.Pathway);
}
//Complete the process
FindingPathway = false;
return;
}
//Find the new current node, then iterate through all its neighbours
Node Current = GridManager.Instance.FindCheapestNode(OpenSet);
OpenSet.Remove(Current);
foreach (Node Neighbour in GridManager.Instance.GetTraversableNeighbours(Current))
{
//Ignore nodes not listed in the open set
if (!OpenSet.Contains(Neighbour))
{
continue;
}
//check if its cheaper to travel over this neighbour
float NeighbourCost = Current.FScore + GridManager.FindHeuristic(Current, Neighbour);
if (NeighbourCost < Neighbour.FScore)
{
//update this neighbour as the best way to travel
Neighbour.FScore = NeighbourCost;
Neighbour.Parent = Current;
Neighbour.ToggleParentIndicator(true);
Neighbour.PointIndicator(Neighbour.GetDirection(Current));
}
}
}