public static List <SokobanPosition> GetFullPath(SokobanPosition[] path)
{
List <SokobanPosition> result = new List <SokobanPosition>();
for (int i = 0; i < path.Length - 1; i++)
{
var start = path[i];
var stop = path[i + 1];
result.Add(start);
bool[,] visited = new bool[start.Width, start.Height];
visited[start.Player.X, start.Player.Y] = true;
Array.Clear(visited, 0, visited.Length);
PointXY[] stack = new PointXY[start.Width * start.Height];
PointXY[,] track = new PointXY[start.Width, start.Height];
track[start.Player.X, start.Player.Y].X = 0;
track[start.Player.X, start.Player.Y].Y = 0;
int stackTop = 0;
stack[0] = start.Player;
PointXY p;
SokobanPosition found = null;
while (stackTop >= 0)
{
p = stack[stackTop];
stackTop--;
//try push left
if ((start.Map[p.X - 1, p.Y] == Constants.STONE || start.Map[p.X - 1, p.Y] == Constants.GOALSTONE) && (start.Map[p.X - 2, p.Y] == Constants.EMPTY || start.Map[p.X - 2, p.Y] == Constants.GOAL))
{
var next = start.ClonePush(p, Direction.Left);
if (next.GetUniqueId() == stop.GetUniqueId())
{
found = next;
track[p.X - 1, p.Y] = p;
break;
}
}
//try push right
if ((start.Map[p.X + 1, p.Y] == Constants.STONE || start.Map[p.X + 1, p.Y] == Constants.GOALSTONE) && (start.Map[p.X + 2, p.Y] == Constants.EMPTY || start.Map[p.X + 2, p.Y] == Constants.GOAL))
{
var next = start.ClonePush(p, Direction.Right);
if (next.GetUniqueId() == stop.GetUniqueId())
{
found = next;
track[p.X + 1, p.Y] = p;
break;
}
}
//try push up
if ((start.Map[p.X, p.Y - 1] == Constants.STONE || start.Map[p.X, p.Y - 1] == Constants.GOALSTONE) && (start.Map[p.X, p.Y - 2] == Constants.EMPTY || start.Map[p.X, p.Y - 2] == Constants.GOAL))
{
var next = start.ClonePush(p, Direction.Up);
if (next.GetUniqueId() == stop.GetUniqueId())
{
found = next;
track[p.X, p.Y - 1] = p;
break;
}
}
//try push down
if ((start.Map[p.X, p.Y + 1] == Constants.STONE || start.Map[p.X, p.Y + 1] == Constants.GOALSTONE) && (start.Map[p.X, p.Y + 2] == Constants.EMPTY || start.Map[p.X, p.Y + 2] == Constants.GOAL))
{
var next = start.ClonePush(p, Direction.Down);
if (next.GetUniqueId() == stop.GetUniqueId())
{
found = next;
track[p.X, p.Y + 1] = p;
break;
}
}
//try walk left
if (!visited[p.X - 1, p.Y] && (start.Map[p.X - 1, p.Y] == Constants.EMPTY || start.Map[p.X - 1, p.Y] == Constants.GOAL))
{
stackTop++;
stack[stackTop].X = p.X - 1;
stack[stackTop].Y = p.Y;
visited[p.X - 1, p.Y] = true;
track[p.X - 1, p.Y] = p;
}
//try walk right
if (!visited[p.X + 1, p.Y] && (start.Map[p.X + 1, p.Y] == Constants.EMPTY || start.Map[p.X + 1, p.Y] == Constants.GOAL))
{
stackTop++;
stack[stackTop].X = p.X + 1;
stack[stackTop].Y = p.Y;
visited[p.X + 1, p.Y] = true;
track[p.X + 1, p.Y] = p;
}
//try walk up
if (!visited[p.X, p.Y - 1] && (start.Map[p.X, p.Y - 1] == Constants.EMPTY || start.Map[p.X, p.Y - 1] == Constants.GOAL))
{
stackTop++;
stack[stackTop].X = p.X;
stack[stackTop].Y = p.Y - 1;
visited[p.X, p.Y - 1] = true;
track[p.X, p.Y - 1] = p;
}
//try walk down
if (!visited[p.X, p.Y + 1] && (start.Map[p.X, p.Y + 1] == Constants.EMPTY || start.Map[p.X, p.Y + 1] == Constants.GOAL))
{
stackTop++;
stack[stackTop].X = p.X;
stack[stackTop].Y = p.Y + 1;
visited[p.X, p.Y + 1] = true;
track[p.X, p.Y + 1] = p;
}
}
if (found != null)
{
var t = stop.Player;
List <SokobanPosition> intermediate = new List <SokobanPosition>();
while (!(t.X == start.Player.X && t.Y == start.Player.Y))
{
SokobanPosition pos = start.Clone();
pos.Player.X = t.X;
pos.Player.Y = t.Y;
if (!(t.X == stop.Player.X && t.Y == stop.Player.Y))
{
intermediate.Add(pos);
}
t = track[t.X, t.Y];
}
intermediate.Reverse();
result.AddRange(intermediate);
}
}
result.Add(path[path.Length - 1]);
return(result);
}
private void CreateDeadlockMap()
{
this.DeadlockMap = new bool[this.Width, this.Height];
bool[,] visited = new bool[this.Width, this.Height];
PointXY[] stack = new PointXY[this.Width * this.Height];
int stackTop = 0;
PointXY p;
var empty = new SokobanPosition()
{
Width = this.Width, Height = this.Height
};
empty.Map = new byte[this.Width, this.Height];
empty.Stones = new PointXY[0];
empty.Goals = new PointXY[0];
empty.StonesMap = new byte[this.Width, this.Height];
empty.Player = this.Player;
// create list of goals
var goals = new List <PointXY>();
for (int x = 0; x < this.Width; x++)
{
for (int y = 0; y < this.Height; y++)
{
if (this.Map[x, y] == Constants.GOAL || this.Map[x, y] == Constants.GOALSTONE)
{
PointXY g;
g.X = x;
g.Y = y;
goals.Add(g);
}
this.DeadlockMap[x, y] = true;
if (this.Map[x, y] == Constants.WALL)
{
empty.Map[x, y] = Constants.WALL;
}
else
{
empty.Map[x, y] = Constants.EMPTY;
}
}
}
foreach (var checkGoal in goals)
{
//prepare map with one stone
var start = new SokobanPosition()
{
Width = this.Width, Height = this.Height
};
start.Map = new byte[this.Width, this.Height];
start.StonesMap = new byte[this.Width, this.Height];
start.Stones = new PointXY[1];
start.Goals = new PointXY[1];
start.Goals[0] = checkGoal;
start.Stones[0] = checkGoal;
start.StonesMap[checkGoal.X, checkGoal.Y] = 1;
start.Player = this.Player;
for (int x = 0; x < this.Width; x++)
{
for (int y = 0; y < this.Height; y++)
{
start.Map[x, y] = this.Map[x, y];
if (start.Map[x, y] == Constants.STONE || start.Map[x, y] == Constants.GOAL || start.Map[x, y] == Constants.GOALSTONE)
{
start.Map[x, y] = Constants.EMPTY;
}
if (x == checkGoal.X && y == checkGoal.Y)
{
start.Map[x, y] = Constants.STONE;
DeadlockMap[x, y] = false;
}
}
}
//search pull posibilities
List <SokobanPosition> nodesToCheck = new List <SokobanPosition>();
nodesToCheck.Add(start);
HashSet <string> visitedNodes = new HashSet <string>();
while (nodesToCheck.Count > 0)
{
var node = nodesToCheck.ElementAt(0);
nodesToCheck.RemoveAt(0);
visitedNodes.Add(node.GetUniqueId());
// add pulls for any reachable player position
Array.Clear(visited, 0, visited.Length);
stack[0] = node.Player;
visited[node.Player.X, node.Player.Y] = true;
stackTop = 0;
while (stackTop >= 0)
{
p = stack[stackTop];
stackTop--;
//try pull right
if ((node.Map[p.X - 1, p.Y] == Constants.STONE) && (node.Map[p.X + 1, p.Y] == Constants.EMPTY))
{
var next = node.ClonePull(p, Direction.Right);
if (!visitedNodes.Contains(next.GetUniqueId()) && !nodesToCheck.Any(n => n.GetUniqueId() == next.GetUniqueId()))
{
nodesToCheck.Add(next);
this.DeadlockMap[p.X, p.Y] = false;
}
}
//try pull left
if ((node.Map[p.X + 1, p.Y] == Constants.STONE) && (node.Map[p.X - 1, p.Y] == Constants.EMPTY))
{
var next = node.ClonePull(p, Direction.Left);
if (!visitedNodes.Contains(next.GetUniqueId()) && !nodesToCheck.Any(n => n.GetUniqueId() == next.GetUniqueId()))
{
nodesToCheck.Add(next);
this.DeadlockMap[p.X, p.Y] = false;
}
}
//try pull down
if ((node.Map[p.X, p.Y - 1] == Constants.STONE) && (node.Map[p.X, p.Y + 1] == Constants.EMPTY))
{
var next = node.ClonePull(p, Direction.Down);
if (!visitedNodes.Contains(next.GetUniqueId()) && !nodesToCheck.Any(n => n.GetUniqueId() == next.GetUniqueId()))
{
nodesToCheck.Add(next);
this.DeadlockMap[p.X, p.Y] = false;
}
}
//try pull up
if ((node.Map[p.X, p.Y + 1] == Constants.STONE) && (node.Map[p.X, p.Y - 1] == Constants.EMPTY))
{
var next = node.ClonePull(p, Direction.Up);
if (!visitedNodes.Contains(next.GetUniqueId()) && !nodesToCheck.Any(n => n.GetUniqueId() == next.GetUniqueId()))
{
nodesToCheck.Add(next);
this.DeadlockMap[p.X, p.Y] = false;
}
}
//try walk left
if (!visited[p.X - 1, p.Y] && (node.Map[p.X - 1, p.Y] == Constants.EMPTY || node.Map[p.X - 1, p.Y] == Constants.GOAL))
{
stackTop++;
stack[stackTop].X = p.X - 1;
stack[stackTop].Y = p.Y;
visited[p.X - 1, p.Y] = true;
}
//try walk right
if (!visited[p.X + 1, p.Y] && (node.Map[p.X + 1, p.Y] == Constants.EMPTY || node.Map[p.X + 1, p.Y] == Constants.GOAL))
{
stackTop++;
stack[stackTop].X = p.X + 1;
stack[stackTop].Y = p.Y;
visited[p.X + 1, p.Y] = true;
}
//try walk up
if (!visited[p.X, p.Y - 1] && (node.Map[p.X, p.Y - 1] == Constants.EMPTY || node.Map[p.X, p.Y - 1] == Constants.GOAL))
{
stackTop++;
stack[stackTop].X = p.X;
stack[stackTop].Y = p.Y - 1;
visited[p.X, p.Y - 1] = true;
}
//try walk down
if (!visited[p.X, p.Y + 1] && (node.Map[p.X, p.Y + 1] == Constants.EMPTY || node.Map[p.X, p.Y + 1] == Constants.GOAL))
{
stackTop++;
stack[stackTop].X = p.X;
stack[stackTop].Y = p.Y + 1;
visited[p.X, p.Y + 1] = true;
}
}
}
}
// remove deadlocks outside reachable area
Array.Clear(visited, 0, visited.Length);
stack[0] = empty.Player;
visited[empty.Player.X, empty.Player.Y] = true;
stackTop = 0;
while (stackTop >= 0)
{
p = stack[stackTop];
stackTop--;
//try walk left
if (!visited[p.X - 1, p.Y] && (empty.Map[p.X - 1, p.Y] == Constants.EMPTY || empty.Map[p.X - 1, p.Y] == Constants.GOAL))
{
stackTop++;
stack[stackTop].X = p.X - 1;
stack[stackTop].Y = p.Y;
visited[p.X - 1, p.Y] = true;
}
//try walk right
if (!visited[p.X + 1, p.Y] && (empty.Map[p.X + 1, p.Y] == Constants.EMPTY || empty.Map[p.X + 1, p.Y] == Constants.GOAL))
{
stackTop++;
stack[stackTop].X = p.X + 1;
stack[stackTop].Y = p.Y;
visited[p.X + 1, p.Y] = true;
}
//try walk up
if (!visited[p.X, p.Y - 1] && (empty.Map[p.X, p.Y - 1] == Constants.EMPTY || empty.Map[p.X, p.Y - 1] == Constants.GOAL))
{
stackTop++;
stack[stackTop].X = p.X;
stack[stackTop].Y = p.Y - 1;
visited[p.X, p.Y - 1] = true;
}
//try walk down
if (!visited[p.X, p.Y + 1] && (empty.Map[p.X, p.Y + 1] == Constants.EMPTY || empty.Map[p.X, p.Y + 1] == Constants.GOAL))
{
stackTop++;
stack[stackTop].X = p.X;
stack[stackTop].Y = p.Y + 1;
visited[p.X, p.Y + 1] = true;
}
}
for (int x = 0; x < this.Width; x++)
{
for (int y = 0; y < this.Height; y++)
{
if (!visited[x, y])
{
this.DeadlockMap[x, y] = false;
}
}
}
}
public SokobanPosition ClonePull(PointXY p, Direction direction)
{
var clone = this.Clone();
switch (direction)
{
case Direction.Left:
clone.Player.X = p.X - 1;
clone.Player.Y = p.Y;
clone.Map[p.X + 1, p.Y] = this.Map[p.X + 1, p.Y] == Constants.STONE ? Constants.EMPTY : Constants.GOAL;
clone.Map[p.X, p.Y] = this.Map[p.X, p.Y] == Constants.EMPTY ? Constants.STONE : Constants.GOALSTONE;
clone.stoneMovedFrom.X = p.X + 1;
clone.stoneMovedFrom.Y = p.Y;
clone.stoneMovedTo.X = p.X;
clone.stoneMovedTo.Y = p.Y;
break;
case Direction.Right:
clone.Player.X = p.X + 1;
clone.Player.Y = p.Y;
clone.Map[p.X - 1, p.Y] = this.Map[p.X - 1, p.Y] == Constants.STONE ? Constants.EMPTY : Constants.GOAL;
clone.Map[p.X, p.Y] = this.Map[p.X, p.Y] == Constants.EMPTY ? Constants.STONE : Constants.GOALSTONE;
clone.stoneMovedFrom.X = p.X - 1;
clone.stoneMovedFrom.Y = p.Y;
clone.stoneMovedTo.X = p.X;
clone.stoneMovedTo.Y = p.Y;
break;
case Direction.Up:
clone.Player.X = p.X;
clone.Player.Y = p.Y - 1;
clone.Map[p.X, p.Y + 1] = this.Map[p.X, p.Y + 1] == Constants.STONE ? Constants.EMPTY : Constants.GOAL;
clone.Map[p.X, p.Y] = this.Map[p.X, p.Y] == Constants.EMPTY ? Constants.STONE : Constants.GOALSTONE;
clone.stoneMovedFrom.X = p.X;
clone.stoneMovedFrom.Y = p.Y + 1;
clone.stoneMovedTo.X = p.X;
clone.stoneMovedTo.Y = p.Y;
break;
case Direction.Down:
clone.Player.X = p.X;
clone.Player.Y = p.Y + 1;
clone.Map[p.X, p.Y - 1] = this.Map[p.X, p.Y - 1] == Constants.STONE ? Constants.EMPTY : Constants.GOAL;
clone.Map[p.X, p.Y] = this.Map[p.X, p.Y] == Constants.EMPTY ? Constants.STONE : Constants.GOALSTONE;
clone.stoneMovedFrom.X = p.X;
clone.stoneMovedFrom.Y = p.Y - 1;
clone.stoneMovedTo.X = p.X;
clone.stoneMovedTo.Y = p.Y;
break;
}
int stoneIdx = clone.StonesMap[clone.stoneMovedFrom.X, clone.stoneMovedFrom.Y];
clone.StonesMap[clone.stoneMovedTo.X, clone.stoneMovedTo.Y] = (byte)stoneIdx;
clone.StonesMap[clone.stoneMovedFrom.X, clone.stoneMovedFrom.Y] = 0;
clone.Stones[stoneIdx - 1] = clone.stoneMovedTo;
clone.NormalizedPlayer.X = 0;
clone.NormalizedPlayer.Y = 0;
if (this.Binary != null)
{
//clone.Binary[2 + py * this.Width + px] = 0;
switch (direction)
{
case Direction.Left:
//clone.Binary[2 + py * this.Width + px - 1] = 1;
clone.SetBinaryBit(p.X + 1, p.Y, 0);
clone.SetBinaryBit(p.X, p.Y, 1);
break;
case Direction.Right:
//clone.Binary[2 + py * this.Width + px + 1] = 1;
clone.SetBinaryBit(p.X - 1, p.Y, 0);
clone.SetBinaryBit(p.X, p.Y, 1);
break;
case Direction.Up:
//clone.Binary[2 + (py - 1) * this.Width + px] = 1;
clone.SetBinaryBit(p.X, p.Y + 1, 0);
clone.SetBinaryBit(p.X, p.Y, 1);
break;
case Direction.Down:
//clone.Binary[2 + (py + 1) * this.Width + px] = 1;
clone.SetBinaryBit(p.X, p.Y - 1, 0);
clone.SetBinaryBit(p.X, p.Y, 1);
break;
}
}
return(clone);
}
public string GetUniqueId()
{
bool changed = false;
if (this.Binary == null)
{
this.Binary = new byte[2 + this.Width * this.Height / 8 + 1];
for (int x = 0; x < this.Width; x++)
{
for (int y = 0; y < this.Height; y++)
{
this.SetBinaryBit(x, y, (byte)((this.Map[x, y] == Constants.STONE || this.Map[x, y] == Constants.GOALSTONE) ? 1 : 0));
}
}
changed = true;
}
if (this.NormalizedPlayer.X == 0 || this.NormalizedPlayer.Y == 0)
{
Array.Clear(VisitedMap, 0, VisitedMap.Length);
Stack[0] = this.Player;
VisitedMap[this.Player.X, this.Player.Y] = true;
int stackTop = 0;
PointXY p;
this.NormalizedPlayer.X = this.Width;
this.NormalizedPlayer.Y = this.Height;
while (stackTop >= 0)
{
p = Stack[stackTop];
stackTop--;
if (p.Y < this.NormalizedPlayer.Y)
{
this.NormalizedPlayer = p;
}
if (p.Y == this.NormalizedPlayer.Y && p.X < this.NormalizedPlayer.X)
{
this.NormalizedPlayer = p;
}
//try walk left
if (!VisitedMap[p.X - 1, p.Y] && (this.Map[p.X - 1, p.Y] == Constants.EMPTY || this.Map[p.X - 1, p.Y] == Constants.GOAL))
{
stackTop++;
Stack[stackTop].X = p.X - 1;
Stack[stackTop].Y = p.Y;
VisitedMap[p.X - 1, p.Y] = true;
}
//try walk right
if (!VisitedMap[p.X + 1, p.Y] && (this.Map[p.X + 1, p.Y] == Constants.EMPTY || this.Map[p.X + 1, p.Y] == Constants.GOAL))
{
stackTop++;
Stack[stackTop].X = p.X + 1;
Stack[stackTop].Y = p.Y;
VisitedMap[p.X + 1, p.Y] = true;
}
//try walk up
if (!VisitedMap[p.X, p.Y - 1] && (this.Map[p.X, p.Y - 1] == Constants.EMPTY || this.Map[p.X, p.Y - 1] == Constants.GOAL))
{
stackTop++;
Stack[stackTop].X = p.X;
Stack[stackTop].Y = p.Y - 1;
VisitedMap[p.X, p.Y - 1] = true;
}
//try walk down
if (!VisitedMap[p.X, p.Y + 1] && (this.Map[p.X, p.Y + 1] == Constants.EMPTY || this.Map[p.X, p.Y + 1] == Constants.GOAL))
{
stackTop++;
Stack[stackTop].X = p.X;
Stack[stackTop].Y = p.Y + 1;
VisitedMap[p.X, p.Y + 1] = true;
}
}
this.Binary[0] = (byte)this.NormalizedPlayer.X;
this.Binary[1] = (byte)this.NormalizedPlayer.Y;
changed = true;
}
if (string.IsNullOrWhiteSpace(this.CachedUniqueId) || changed)
{
this.CachedUniqueId = Convert.ToBase64String(this.Binary);
//this.CachedUniqueId = Encoding.Unicode.GetString(this.Binary);
//this.CachedUniqueId = BitConverter.ToString(this.Binary).Replace("-", string.Empty);
}
return(CachedUniqueId);
}