public bool containsTile(Tile inputTile)
{
bool containsTileReturn = false;
int index = this.AllMoveableTiles.FindIndex(tile => (tile.xPos == inputTile.xPos && tile.yPos == inputTile.yPos));
if (index != -1)
containsTileReturn = true;
return containsTileReturn;
}
public const int baseCost = 1; //the cost of moving to any node. Set to 1 to make this simple for now.
#endregion Fields
#region Constructors
public Node(Tile tile)
{
nodeTile = tile;
}
private static List<Node> getAdjacentNodes(Tile startingTile, Map map, List<Node> closedList, Node destinationNode)
{
List<Node> adjacentNodes = new List<Node>();
List<Tile> tilesToCheck = new List<Tile>();
Node startingNode = new Node(startingTile);
int startingX = startingTile.xPos;
int startingY = startingTile.yPos;
if (map.coordinatesOnMap(startingX, startingY + 1))
tilesToCheck.Add(map.tiles[startingX, startingY + 1]);
if (map.coordinatesOnMap(startingX, startingY - 1))
tilesToCheck.Add(map.tiles[startingX, startingY - 1]);
if (map.coordinatesOnMap(startingX + 1, startingY))
tilesToCheck.Add(map.tiles[startingX + 1, startingY]);
if (map.coordinatesOnMap(startingX - 1, startingY))
tilesToCheck.Add(map.tiles[startingX - 1, startingY]);
foreach (Tile tile in tilesToCheck)
{
//make sure the tile isnt occupied and isnt in the checked list.
if (!tile.isOccupied && !(closedList.FindIndex(node => node.nodeTile == tile) >= 0))
{
Node newNode = new Node(tile);
newNode.FValue = calculateFValue(newNode, destinationNode);
newNode.parentNode = startingNode;
adjacentNodes.Add(newNode);
}
}
return adjacentNodes;
}
public static List<Tile> shortestPath(Map map, Tile startingTile, Tile destinationTile)
{
List<Tile> path = new List<Tile>();
List<Node> openNodes = new List<Node>();
List<Node> closedNodes = new List<Node>();
List<Node> adjacentNodes = new List<Node>();
bool reachedDestination = false;
//initialize. Set starting tile to be the first open node.
Node startingNode = new Node(startingTile);
Node destinationNode = new Node(destinationTile);
startingNode.FValue = calculateFValue(startingNode, destinationNode);
openNodes.Add(startingNode);
Node nodeToEval = startingNode;
while (openNodes.Count > 0) // while nodeToEval != destinationNode ?
{
//get adjacent nodes and add them to openNodes
adjacentNodes = getAdjacentNodes(nodeToEval.nodeTile, map, closedNodes, destinationNode);
openNodes.AddRange(adjacentNodes);
openNodes.Remove(nodeToEval);
closedNodes.Add(nodeToEval);
//remove nodeToEval from open list, add to closed list
if (nodeToEval.nodeTile.xPos == destinationNode.nodeTile.xPos && nodeToEval.nodeTile.yPos == destinationNode.nodeTile.yPos)
{
reachedDestination = true;
break;
}
//Now we find the NEXT node to evaluate
//We search for the lowest F value in the whole open list after adding the ajacent nodes above
int lowestFValue = openNodes.Min(node => node.FValue);
//Now get the node with that lowest value - thats our next node to examine.
Node nextNodeToEval = openNodes.Find(node => node.FValue == lowestFValue);
nodeToEval = nextNodeToEval;
}
if (reachedDestination == true)
{
//done! collect the destination and all parent nodes in a list
path.Add(nodeToEval.nodeTile);
Node nextParentNode = nodeToEval.parentNode;
while (nextParentNode != null)
{
path.Add(nextParentNode.nodeTile);
//find parent node in the closed list
Node currentParentNode = closedNodes.Find(node => node.nodeTile.xPos == nextParentNode.nodeTile.xPos && node.nodeTile.yPos == nextParentNode.nodeTile.yPos);
nextParentNode = currentParentNode.parentNode;
}
}
// find adjacent available nodes and add nodeToEval to the closed list afterwards.
//adjacentNodes = getAdjacentNodes(nodeToEval.nodeTile, map, closedNodes, destinationNode);
//openNodes.Remove(nodeToEval);
// openNodes.AddRange(adjacentNodes);
return path;
}
public static List<Tile> getAdjacentUncheckedTiles(Tile StartingTile, Map map, List<Tile> checkedTiles)
{
List<Tile> AdjacentTiles = new List<Tile>();
List<Tile> TilesToCheck = new List<Tile>();
int startingTileX = StartingTile.xPos;
int startingTileY = StartingTile.yPos;
//check if the tiles passed in here resolve to null
if (map.coordinatesOnMap(startingTileX, startingTileY + 1) )
TilesToCheck.Add(map.tiles[startingTileX, startingTileY + 1]);
if (map.coordinatesOnMap(startingTileX, startingTileY - 1))
TilesToCheck.Add(map.tiles[startingTileX, startingTileY - 1]);
if (map.coordinatesOnMap(startingTileX + 1, startingTileY))
TilesToCheck.Add(map.tiles[startingTileX + 1, startingTileY]);
if (map.coordinatesOnMap(startingTileX - 1, startingTileY))
TilesToCheck.Add(map.tiles[startingTileX - 1, startingTileY]);
if (TilesToCheck.Count > 0)
{
foreach (Tile currentTile in TilesToCheck)
{
if (!currentTile.Equals(null)) // if the current tile is off the map, ie (1,0), the current tile will be null.
{
if (!currentTile.isOccupied && !checkedTiles.Contains(currentTile))
{
AdjacentTiles.Add(currentTile);
}
}
}
}
return AdjacentTiles;
}
public static List<Tile> shortestPath(Map map, Tile startingTile, Tile destinationTile)
{
List<Tile> path = new List<Tile>();
List<Node> openNodes = new List<Node>();
List<Node> closedNodes = new List<Node>();
List<Node> adjacentNodes = new List<Node>();
bool reachedDestination = false;
//initialize. Set starting tile to be the first open node.
Node startingNode = new Node(startingTile);
Node destinationNode = new Node(destinationTile);
startingNode.FValue = calculateFValue(startingNode, destinationNode);
openNodes.Add(startingNode);
Node nodeToEval = startingNode;
while (openNodes.Count > 0) // while nodeToEval != destinationNode ?
{
//get adjacent nodes and add them to openNodes
adjacentNodes = getAdjacentNodes(nodeToEval.nodeTile, map, closedNodes, destinationNode);
openNodes.AddRange(adjacentNodes);
openNodes.Remove(nodeToEval);
closedNodes.Add(nodeToEval);
//remove nodeToEval from open list, add to closed list
if (nodeToEval.nodeTile.xPos == destinationNode.nodeTile.xPos && nodeToEval.nodeTile.yPos == destinationNode.nodeTile.yPos)
{
reachedDestination = true;
break;
}
//Now we find the NEXT node to evaluate
//We search for the lowest F value in the whole open list after adding the ajacent nodes above
int lowestFValue = openNodes.Min(node => node.FValue);
//Now get the node with that lowest value - thats our next node to examine.
Node nextNodeToEval = openNodes.Find(node => node.FValue == lowestFValue);
//this method will give us boring L-shaped paths if two adjacent nodes have the same F value.
//lets try forcing the game to prioritize the one that indicates a change in direction!
if((openNodes.FindAll(node => node.FValue == lowestFValue).Count > 1))
{
List<Node> potentialNextNodesToEval = openNodes.FindAll(node => node.FValue == lowestFValue);
foreach(Node node in potentialNextNodesToEval)
{
if (nodeToEval.parentNode != null){
if (nodeToEval.parentNode.nodeTile.xPos == nodeToEval.nodeTile.xPos && nodeToEval.nodeTile.xPos != node.nodeTile.xPos)
{
//change of direction in x, prioritize this node and exit
nextNodeToEval = node;
break;
}
else if (nodeToEval.parentNode.nodeTile.yPos == nodeToEval.nodeTile.yPos && nodeToEval.nodeTile.yPos != node.nodeTile.yPos)
{
//change of direction in y, prioritize this node and exit
nextNodeToEval = node;
break;
}
}
}
}
nodeToEval = nextNodeToEval;
}
if (reachedDestination == true)
{
//done! collect the destination and all parent nodes in a list
path.Add(nodeToEval.nodeTile);
Node nextParentNode = nodeToEval.parentNode;
while (nextParentNode != null)
{
path.Add(nextParentNode.nodeTile);
//find parent node in the closed list
Node currentParentNode = closedNodes.Find(node => node.nodeTile.xPos == nextParentNode.nodeTile.xPos && node.nodeTile.yPos == nextParentNode.nodeTile.yPos);
nextParentNode = currentParentNode.parentNode;
}
}
// find adjacent available nodes and add nodeToEval to the closed list afterwards.
//adjacentNodes = getAdjacentNodes(nodeToEval.nodeTile, map, closedNodes, destinationNode);
//openNodes.Remove(nodeToEval);
// openNodes.AddRange(adjacentNodes);
return path;
}
public static Tile getCursorCurrentTile(Tile tile, Map map, Point cursorPoint, Rectangle tileRect)
{
//when the cursor is over a tile's rectangle, We need to find the space we're actually selecting. The rectangular sprite just containst the diamond
//So the tile you pass in, is not necessarily the tile youre hovering over - it may be the edge, and therefore, in another tile.
//We want to keep this general in case we chnge tile/asset sizes later. We can use the symmetry in iso art to our advantage.
//Whatever the tile size, the angles will be the same, so the math will scale.
//We have to go through each of the 5 possible areas designated by the given area. The center diamond, and the four sorrounding triangles. We'll do the center diamond first
//if the point isnt in the center diamond, we can use a quick+dirty method of figuring out which triangle its in, and therefore which tile to return.
//first get an array of points that make up the inner diamond
Point[] polygon = new Point[4];
polygon[0] = new Point(tileRect.X + Tile.width / 2, tileRect.Y);
polygon[1] = new Point(tileRect.X, tileRect.Y + Tile.height / 2);
polygon[2] = new Point(tileRect.X + Tile.width / 2, tileRect.Y + Tile.height);
polygon[3] = new Point(tileRect.X + Tile.width, tileRect.Y + Tile.height / 2);
bool insideDiamond = false;
for (int i = 0, j = polygon.Length - 1; i < polygon.Length; j = i++)
{
if ((polygon[i].Y > cursorPoint.Y) != (polygon[j].Y > cursorPoint.Y) &&
cursorPoint.X < (polygon[j].X - polygon[i].X) * (cursorPoint.Y - polygon[i].Y) / (polygon[j].Y - polygon[i].Y) + polygon[i].X)
{
insideDiamond = !insideDiamond;
}
}
if (insideDiamond == true)
{
return tile;
}
else
{
//Ok, point is not in the diamond, so let's see which triangle it's in. Keep in mind that a tile adjacent to the given tile may be off the map.
//Lets create bounding rectangles that contain the triangles in the corner, Then test if the point is in those rectangles. Since its not in the center diamond,
//a hit here means the point is int the correponding triangle.
Rectangle upperLeft = new Rectangle(tileRect.X, tileRect.Y, Tile.width/2, Tile.height/2);
Rectangle upperRight = new Rectangle(tileRect.X + Tile.width / 2, tileRect.Y, Tile.width / 2, Tile.height / 2);
Rectangle lowerLeft = new Rectangle(tileRect.X, tileRect.Y + Tile.height / 2, Tile.width / 2, Tile.height / 2);
Rectangle lowerRight = new Rectangle(tileRect.X + Tile.width / 2, tileRect.Y + Tile.height / 2, Tile.width / 2, Tile.height / 2);
if (upperLeft.Contains(cursorPoint))
{
if (map.coordinatesOnMap(tile.xPos, tile.yPos - 1))
return map.tiles[tile.xPos, tile.yPos - 1];
}
else if (upperRight.Contains(cursorPoint))
{
if (map.coordinatesOnMap(tile.xPos + 1, tile.yPos))
return map.tiles[tile.xPos + 1, tile.yPos];
}
else if (lowerLeft.Contains(cursorPoint))
{
if (map.coordinatesOnMap(tile.xPos - 1, tile.yPos))
return map.tiles[tile.xPos - 1, tile.yPos];
}
else
{
//only one left is bottom right:
if (map.coordinatesOnMap(tile.xPos, tile.yPos + 1))
return map.tiles[tile.xPos, tile.yPos + 1];
}
}
return null;
}