예제 #1
0
        public static List<Point> PathToPill(Maze maze, Point start, Point destination)
        {
            var list = new List<Point>();
            var closedSet = new List<PathNode>();
            var hScore = Math.Abs(start.X - destination.X) + Math.Abs(start.Y - destination.Y);

            var openSet = new List<PathNode>
            {
                new PathNode
                {
                    Position = start,
                    GScore = 0,
                    HScore = hScore,
                    FScore = hScore
                }

            };

            while (openSet.Count != 0)
            {
                var current = BestNode(openSet);
                if (current.Position.Equals(destination))
                {
                    list.Add(new Point { X = current.GScore });
                    list.Add(ReconstructPath(start, current).Position);
                    return list;
                }
                openSet.Remove(current);
                closedSet.Add(current);

                var childpoints = GenerateMoves(maze, current.Position);

                foreach (var childpoint in childpoints)
                {
                    var gScore = current.GScore + 1;
                    hScore = Math.Abs(childpoint.X - destination.X) + Math.Abs(childpoint.Y - destination.Y);
                    var newChild = new PathNode
                    {
                        Position = childpoint,
                        GScore = gScore,
                        HScore = hScore,
                        FScore = gScore + hScore
                    };

                    if (closedSet.Contains(newChild))
                        continue;
                    var _newChild = FindChild(newChild, openSet);
                    if (_newChild != null
                        && gScore < _newChild.GScore)
                    {
                        openSet.Remove(_newChild);
                        current.InsertChild(newChild);
                        openSet.Add(newChild);
                    }
                    else if (_newChild == null)
                    {
                        current.InsertChild(newChild);
                        openSet.Add(newChild);
                    }
                }
            }
            return list;
        }
예제 #2
0
 private static PathNode ReconstructPath(Point start, PathNode current)
 {
     while (current.Parent.Position != start)
         current = current.Parent;
     return current;
 }
예제 #3
0
 private static bool isChildExplored(PathNode root, Point childPoint)
 {
     while (root != null)
     {
         if (root.Position == childPoint)
             return true;
         root = root.Parent;
     }
     return false;
 }
예제 #4
0
 private static PathNode FindChild(PathNode newChild, List<PathNode> openSet)
 {
     foreach (var node in openSet)
         if (node.Position == newChild.Position)
             return node;
     return null;
 }
예제 #5
0
        public static Point SelectPath(Maze maze, Point start, int depth)
        {
            var openSet = new List<PathNode>
            {
                new PathNode{Position = start}
            };
            var closedSet = new List<PathNode>();
            var _depth = 0;

            while (openSet.Count != 0 && _depth < depth)
            {
                var root = openSet.First();
                openSet.Remove(root);

                var childPoints = GenerateMoves(maze, root.Position);

                foreach (var childPoint in childPoints)
                {
                    if (!isChildExplored(root, childPoint))
                    {
                        var _case = maze.GetSymbol(childPoint);
                        switch (_case)
                        {
                            case '.':
                                var newChild = new PathNode
                                {
                                    Position = childPoint,
                                    Score = root.Score + 1
                                };
                                root.InsertChild(newChild);
                                openSet.Add(newChild);
                                break;
                            case '*':
                                newChild = new PathNode
                                {
                                    Position = childPoint,
                                    Score = root.Score + 10
                                };
                                root.InsertChild(newChild);
                                openSet.Add(newChild);
                                break;
                            default:
                                break;
                        }
                    }
                }
                closedSet.Add(root);
                _depth++;
            }

            var current = new PathNode();
            if (openSet.Count != 0)
            {
                current = closedSet.OrderByDescending(pathNode => pathNode.Score).First();
                return ReconstructPath(start, current).Position;
            }

            current = closedSet.OrderByDescending(pathNode => pathNode.Score).First();
            var longestStreaks = closedSet.Where(pathNode => pathNode.Score == current.Score).ToList();
            if (longestStreaks.Count == 1)
                return ReconstructPath(start, current).Position;
            var random = new Random();
            var longestStreakIndex = random.Next(0, longestStreaks.Count);
            return ReconstructPath(start, longestStreaks[longestStreakIndex]).Position;
        }
예제 #6
0
 public void InsertChild(PathNode newChild)
 {
     newChild.parent = this;
 }