public static SearchResult BestFirstSearch(Grid grid, Point startPos, Point endPos)
{
FakePriorityQueue <Point> queue = new FakePriorityQueue <Point>();
Dictionary <Point, float> distanceMap = new Dictionary <Point, float>();
Dictionary <Point, Point> visitedMap = new Dictionary <Point, Point>();
queue.Enqueue(startPos, 0);
distanceMap.Add(startPos, 0);
visitedMap.Add(startPos, null);
while (!queue.Empty)
{
Point current = queue.Dequeue();
if (current.Equals(endPos))
{
return(new SearchResult
{
Path = GeneratePath(visitedMap, current),
Visited = new List <Point>(visitedMap.Keys)
});
}
foreach (Point neighbour in grid.GetAdjacentCells(current))
{
if (!visitedMap.ContainsKey(neighbour))
{
float priority = Heuristic(endPos, neighbour);
queue.Enqueue(neighbour, priority);
visitedMap.Add(neighbour, current);
distanceMap.Add(neighbour, distanceMap[current] + grid.GetCostOfEnteringCell(neighbour));
}
}
}
return(new SearchResult());
}
public static SearchResult DijkstraGeneral(Grid grid, Point startPos)
{
FakePriorityQueue <Point> queue = new FakePriorityQueue <Point>();
Dictionary <Point, float> distanceMap = new Dictionary <Point, float>();
Dictionary <Point, Point> visitedMap = new Dictionary <Point, Point>();
queue.Enqueue(startPos, 0);
distanceMap.Add(startPos, 0);
visitedMap.Add(startPos, null);
while (!queue.Empty)
{
Point current = queue.Dequeue();
foreach (Point adj in grid.GetAdjacentCells(current))
{
float newDist = distanceMap[current] + grid.GetCostOfEnteringCell(adj);
if (!distanceMap.ContainsKey(adj) || newDist < distanceMap[adj])
{
distanceMap[adj] = newDist;
visitedMap[adj] = current;
queue.Enqueue(adj, newDist);
}
}
}
return(new SearchResult()
{
VisitedMap = visitedMap,
DistanceMap = distanceMap
});
}
public static SearchResult AStarSearchWithCost(Grid grid, Point startPos, Point endPos,
Dictionary <Point, float> costMap)
{
FakePriorityQueue <Point> queue = new FakePriorityQueue <Point>();
Dictionary <Point, float> costSoFar = new Dictionary <Point, float>();
Dictionary <Point, Point> cameFrom = new Dictionary <Point, Point>();
queue.Enqueue(startPos, 0);
costSoFar[startPos] = 0;
cameFrom[startPos] = null;
while (!queue.Empty)
{
Point current = queue.Dequeue();
if (current.Equals(endPos))
{
return(new SearchResult
{
Path = GeneratePath(cameFrom, current),
Visited = new List <Point>(cameFrom.Keys)
});
}
foreach (Point neighbour in grid.GetAdjacentCells(current))
{
float cost = costMap.ContainsKey(neighbour) ? costMap[neighbour] : 1;
float newCost = costSoFar[current] + cost;
if (!costSoFar.ContainsKey(neighbour) || newCost < costSoFar[neighbour])
{
costSoFar[neighbour] = newCost;
float priority = newCost + Heuristic(endPos, neighbour);
queue.Enqueue(neighbour, priority);
cameFrom[neighbour] = current;
}
}
}
return(new SearchResult());
}