public PathFindTile(Point location, int g, int h, PathFindTile parent)
{
_location = location;
_g = g;
_h = h;
_parent = parent;
}
public List <PathFindTile> GetNeighbours(Point location)
{
List <PathFindTile> neighboursList = new List <PathFindTile>();
int c = location.X;
int r = location.Y;
//up
int upR = r - 1;
int upC = c;
if (upR > 0 && upC > 0 &&
_gameField[upC, upR] == (int)PathFindObject.Path)
{
PathFindTile pft = new PathFindTile(new Point(upC, upR), 0, 0, null);
neighboursList.Add(pft);
}
//down
int downR = r + 1;
int downC = c;
if (downR > 0 && downC > 0 &&
_gameField[downC, downR] == (int)PathFindObject.Path)
{
PathFindTile pft = new PathFindTile(new Point(downC, downR), 0, 0, null);
neighboursList.Add(pft);
}
//left
int leftR = r;
int leftC = c - 1;
if (leftR > 0 && leftC > 0 &&
_gameField[leftC, leftR] == (int)PathFindObject.Path)
{
PathFindTile pft = new PathFindTile(new Point(leftC, leftR), 0, 0, null);
neighboursList.Add(pft);
}
//right
int rightR = r;
int rightC = c + 1;
if (rightR > 0 && rightC > 0 &&
_gameField[rightC, rightR] == (int)PathFindObject.Path)
{
PathFindTile pft = new PathFindTile(new Point(rightC, rightR), 0, 0, null);
neighboursList.Add(pft);
}
return(neighboursList);
}
public Stack <Point> PathFind(Point startTile, Point endTile)
{
Stack <Point> result = new Stack <Point>();
Stack <Point> resultPath = new Stack <Point>();
List <PathFindTile> openList = new List <PathFindTile>();
List <PathFindTile> closedList = new List <PathFindTile>();
//push start node on open list
openList.Add(new PathFindTile(startTile, 0, 0, null));
//while open list is not empty
while (openList.Count > 0)
{
//currentNode = find lowest f in openList
int lowInd = 0;
for (int i = 0; i < openList.Count; i++)
{
if (openList[i].F < openList[lowInd].F)
{
lowInd = i;
}
}
PathFindTile currentNode = openList[lowInd];
//if currentNode is final, return the successful path
if (currentNode.Location == endTile)
{
PathFindTile curr = currentNode;
while (curr.Parent != null)
{
resultPath.Push(curr.Location);
curr = curr.Parent;
}
return(resultPath);
}//if
//push currentNode onto closedList and remove from openList
closedList.Add(currentNode);
openList.Remove(currentNode);
//foreach neighbor of currentNode
List <PathFindTile> neighbours = new List <PathFindTile>();
neighbours = GetNeighbours(currentNode.Location);
for (int i = 0; i < neighbours.Count; i++)
{
//if neighbor is not in openList
// save g, h, and f then save the current parent
// add neighbor to openList
PathFindTile neighbour = neighbours[i];
bool isInOpenList = false;
for (int j = 0; j < openList.Count; j++)
{
if (openList[j].Location == neighbour.Location)
{
isInOpenList = true;
break;
}
}
int gScore = currentNode.G + 1;
bool gScoreIsBest = false;
if (isInOpenList == false)
{
PathFindTile n = new PathFindTile(neighbours[i].Location, gScore, CalculateDistance(currentNode.Location, endTile), currentNode);
openList.Add(n);
}
else if (gScore < neighbour.G)
{
gScoreIsBest = true;
}
if (gScoreIsBest)
{
neighbour.Parent = currentNode;
neighbour.G = gScore;
neighbour.H = CalculateDistance(neighbour.Location, endTile);
}
} //for
} //while
return(result);
}
