public int AStarBinarySearch(List<AStarTile> openList, AStarTile tileToInsert)
{
// List<AStarTile> list = openList; //The AStarTile list to consider
// AStarTile tile = tileToInsert; //The tile to insert
// bool done = false; //Loop condition
// int min = 0; //The minimum index number to look at
// int max = list.Count - 1; //The maximum index number to look at
// int range = max - min; //The range between max and min
//
// int f = tile.f; //The f cost to insert and compare with
// //bool totalIsEven; //Whether the number of insert points is even or odd
// //if ((range + 1) % 2 == 0) //If insert points is even
// //{
// // totalIsEven = true;
// //}
// //else //If odd
// //{
// // totalIsEven = false;
// //}
//
// while (!done) //Loop until done with the search
// {
// if (list.Count == 0) //If nothing's there, then obviously the new Tile will have the lowest f cost
// {
// done = true; //Nothing's there already, so we're done
// }
//
// if (list.Count == 1)
// {
// if (f < list[0].f)
// {
// indexToInsertAt = 0;
// }
// else if (f > list[0].f)
// {
// indexToInsertAt = 1;
// }
// else
// {
// indexToInsertAt = random.Next(0, 1);
// }
// }
//
// if (list.Count == 2)
// {
//
// }
// }
return -1; //Error if it gets here
}
public Stack<byte> AStarPathfind(Creature creature, Vector2 pointA, Vector2 pointB)
{
Stack<byte> path = new Stack<byte>();
if (ConvertAbsolutePosToRelative(pointA, pointB) > 0)
{
path.Push((byte)ConvertAbsolutePosToRelative(pointA, pointB));
return path;
}
if (pointA.X == pointB.X && pointA.Y == pointB.Y)
{
path.Push(5);
return path;
}
#region Variables
//int g = 0;
//int h = (int)(Math.Abs(pointB.X - pointA.X) + (int)Math.Abs(pointB.Y - pointA.Y));
bool done = false;
AStarTile currentTile = new AStarTile(pointA, new Vector2(-1, -1), 0,
100 * ((int)(Math.Abs(pointB.X - pointA.X) + (int)Math.Abs(pointB.Y - pointA.Y))));
List<AStarTile> openList = new List<AStarTile>();
List<AStarTile> closedList = new List<AStarTile>();
#endregion
openList.Add(currentTile); //Add the current tile
while (!done)
{
#region Find new current tile
currentTile = openList[0]; //The lowest F cost tile is the current tile
openList.RemoveAt(0); //Removed from the open list
closedList.Add(currentTile); //And placed in the closed list
#endregion
if (currentTile.pos == pointB) //If target has been just added to closed list
{
done = true;
}
#region Define adjacent vectors
Vector2[] adjacent = new Vector2[8];
adjacent[0] = new Vector2(currentTile.pos.X - 1, currentTile.pos.Y + 1); //Adjacent tile at position 1
adjacent[1] = new Vector2(currentTile.pos.X, currentTile.pos.Y + 1); //Adjacent tile at position 2
adjacent[2] = new Vector2(currentTile.pos.X + 1, currentTile.pos.Y + 1); //Adjacent tile at position 3
adjacent[3] = new Vector2(currentTile.pos.X - 1, currentTile.pos.Y); //Adjacent tile at position 4
adjacent[4] = new Vector2(currentTile.pos.X + 1, currentTile.pos.Y); //Adjacent tile at position 6
adjacent[5] = new Vector2(currentTile.pos.X - 1, currentTile.pos.Y - 1); //Adjacent tile at position 7
adjacent[6] = new Vector2(currentTile.pos.X, currentTile.pos.Y - 1); //Adjacent tile at position 8
adjacent[7] = new Vector2(currentTile.pos.X + 1, currentTile.pos.Y - 1); //Adjacent tile at position 9
#endregion
#region Process adjacent tiles to Current Tile
for (int i = 0; i <= 7; i++) // the adjacent tiles 0-7, all 8
{
if (adjacent[i].X < 0 || adjacent[i].X > GRIDW-1 || adjacent[i].Y < 0 || adjacent[i].Y > GRIDH-1)
{
i++;
break;
}
bool shouldBeOpen = true;
bool isAlreadyOpen = false;
bool closedDoor = false; //Whether this tile has a door in it.
int indexOnOpen = -1;
//if (tileArray[(int)adjacent[i].X, (int)adjacent[i].Y].fixtureLibrary.Count > 0)
//{
// foreach (Fixture fixture in tileArray[(int)adjacent[i].X, (int)adjacent[i].Y].fixtureLibrary)
// {
// if (fixture is Door) //If it's a door
// {
// Door door = (Door)fixture;
// if (!door.isOpen) //If the door is closed
// closedDoor = true;
// }
// }
//}
if (tileArray[(int)adjacent[i].X, (int)adjacent[i].Y] == null)
{
shouldBeOpen = false;
}
else if (this.tileArray[(int)adjacent[i].X, (int)adjacent[i].Y].isPassable == false &&
!(closedDoor && creature.isDextrous)) //If not passable
{
shouldBeOpen = false; //It's not a candidate if not blocked by door
}
else //If passable
{
foreach (AStarTile j in closedList) //For each closedList item
{
if (j.pos == adjacent[i]) //If a closedList item is the same as the potential tile
{
shouldBeOpen = false; //Not a candidate
}
}
foreach (Creature c in creatures)
if (c.pos == adjacent[i] && adjacent[i] != pointB) //If a creature is in the way
shouldBeOpen = false;
int openListCount = openList.Count;
for (int j = 0; j < openListCount; j++)
{
if (openList[j].pos == adjacent[i]) //If an openList item is the same as the potential tile
{
isAlreadyOpen = true; //Mark it as already on the open list
indexOnOpen = j;
}
}
}
if (shouldBeOpen) //If it should go on the open list
{
int g = 100; //Weight of tile ***IMPROVE THIS LATER***
int h = 100 * ((int)(Math.Abs(pointB.X - adjacent[i].X) + (int)Math.Abs(pointB.Y - adjacent[i].Y))); //Heuristic guess
//int f = g + h; //Definition of f cost
AStarTile newTile = new AStarTile(adjacent[i], currentTile.pos, currentTile.g + g, h, g); //Make an official tile for it
if (isAlreadyOpen) //If already on the open list
{
if (newTile.g < openList[indexOnOpen].g) //If this path to the tile is cheaper than its previous g
{
openList[indexOnOpen] = newTile; //Overwrite its old info with this cheaper info
}
}
else
{
openList.Insert(AStarSequentialSearch(openList, newTile), newTile); //Insert in openList a sequential search according to f cost
//Calculate where this new tile should go with a binary search. ***UNFINISHED***
//AStarBinarySearch(openList, newTile);
}
}
}
if (openList.Count == 0) //If no more tiles to look at, there's no path
{
path.Push(0);
return path;
}
#endregion
}
#region Trace back to starting tile
int oldIndex = -1;
int index = 0;
while (currentTile.parentpos != new Vector2(-1, -1)) //Until parent is starting tile
{
int closedListCount = closedList.Count;
for (int j = 0; j < closedListCount; j++)
{
if (closedList[j].pos == currentTile.parentpos)
{
oldIndex = index;
index = j;
path.Push((byte)ConvertAbsolutePosToRelative(closedList[index].pos, currentTile.pos));
break;
}
}
currentTile = closedList[index];
}
#endregion
currentTile = closedList[oldIndex];
openList.Clear();
closedList.Clear();
return path;
}
public static int AStarSequentialSearch(List<AStarTile> openList, AStarTile tileToInsert)
{
int max = openList.Count - 1;
if (openList.Count == 0) //If the list is empty
{
return 0; //Insert at zero, since nothing's there to mess up
}
if (openList.Count == 1)
{
if (tileToInsert.f < openList[0].f)
{
return 0;
}
else
{
return 1;
}
}
for (int i = 0; i <= max; i++)
{
if (i == max) //If at the far right of the list
{
if (tileToInsert.f >= openList[i].f) //newtile.f > farrightnumber.f
{
return i + 1; //Insert it just to the right of the max number, bumping nothing
}
else
{
return i;
}
}
else if (i == 0) //If at the far left of the list
{
if (tileToInsert.f <= openList[i].f) //newtile.f < farleftnumber.f
{
return 0; //Insert it at index zero, bumping everything to the right one
}
else
{
return 1;
}
}
else
{
if (openList[i - 1].f < tileToInsert.f && tileToInsert.f <= openList[i].f) //If between two
{
return i; //Bump everything it's less than to the right.
}
}
}
return -1; //Error if it makes it here
}
