void MoveBlock(Block blockToMove, float duration)
{
if ((blockToMove.coord - emptyBlock.coord).sqrMagnitude == 1)
{
if (!blockIsMoving && !state.Equals(PuzzleState.Shuffling))
{
source.clip = slide;
source.Play();
}
blocks[blockToMove.coord.x, blockToMove.coord.y] = emptyBlock;
blocks[emptyBlock.coord.x, emptyBlock.coord.y] = blockToMove;
Vector2Int targetCoord = emptyBlock.coord;
emptyBlock.coord = blockToMove.coord;
blockToMove.coord = targetCoord;
Vector2 targetPosition = emptyBlock.transform.position;
emptyBlock.transform.position = blockToMove.transform.position;
blockToMove.MoveToPosition(targetPosition, duration);
blockIsMoving = true;
}
}
public PuzzleResults ApplyAStar(Heuristic heuristic)
{
PriorityQueue <PuzzleState> fringe = new PriorityQueue <PuzzleState>();
// Closed set
HashSet <PuzzleState> visited = new HashSet <PuzzleState>();
// We start with only the initial state generated.
int numGenerated = 1;
int numExpanded = 0;
PuzzleState pathEnd = null;
fringe.Enqueue(InitState, 0);
while (!fringe.IsEmpty())
{
PuzzleState current = fringe.Dequeue();
visited.Add(current);
numExpanded++;
// Goal check.
if (current.Equals(GoalState))
{
pathEnd = current;
break;
}
List <PuzzleState> successors = current.GetSuccessors();
foreach (PuzzleState s in successors)
{
if (!visited.Contains(s))
{
// Compute heuristic value and add to total cost to get priority.
int hValue = Int32.MaxValue;
if (heuristic == Heuristic.MisplacedTiles)
{
hValue = s.ComputeMisplacedTileDistance(GoalState);
}
else if (heuristic == Heuristic.ManhattanDistance)
{
hValue = s.ComputeManhattanDistance(GoalState);
}
else if (heuristic == Heuristic.None)
{
hValue = 0;
}
else
{
throw new ArgumentException("Expected MisplacedTiles or ManhattanDistance heuristic.");
}
int priority = s.Depth + hValue;
bool alreadyExisted = fringe.Enqueue(s, priority);
if (!alreadyExisted)
{
numGenerated++;
}
}
}
}
// Build path into list.
List <PuzzleState> path = new List <PuzzleState>();
PuzzleState currPathNode = pathEnd;
path.Add(currPathNode);
while (currPathNode.Prev != null)
{
path.Add(currPathNode.Prev);
currPathNode = currPathNode.Prev;
}
path.Reverse();
PuzzleResults results = new PuzzleResults(numGenerated, numExpanded, path);
return(results);
}
