A node class for doing path finding on a 2-dimensional map Christy Lock Note: Astar.cs, Heap.cs and Main.cs were originally written by Sune Trundslev 4 Jan 2004 I has made small modifications to Astar.cs and Main.cs to handle the 3d Metaverse Specifically to return waypoints in generic string Lists broken into slope changes. These are returned to BotMe.cs. You can find the original code at http://www.codeproject.com/KB/recipes/csharppathfind.aspx Note that there is no specific license in the code download and the author states " With this class, you should be able to implement your own A* path finding to your own c# projects."
Inheritance: AStarNode
 /// <summary>
 ///     Prints the solution
 /// </summary>
 /// <param name="ASolution">The list that holds the solution</param>
 public static void PrintSolution(ArrayList ASolution)
 {
     for (int j = 0; j < 10; j++)
     {
         for (int i = 0; i < 10; i++)
         {
             bool solution = false;
             foreach (AStarNode2D n in ASolution)
             {
                 AStarNode2D tmp = new AStarNode2D(null, null, 0, i, j);
                 solution = n.IsSameState(tmp);
                 if (solution)
                 {
                     break;
                 }
             }
             if (solution)
             {
                 Console.Write("S ");
             }
             else if (GetMap(i, j) == -1)
             {
                 Console.Write("X ");
             }
             else
             {
                 Console.Write(". ");
             }
         }
         Console.WriteLine("");
     }
 }
        /// <summary>
        ///     Adds a successor to a list if it is not impassible or the parent node
        /// </summary>
        /// <param name="ASuccessors">List of successors</param>
        /// <param name="AX">X-coordinate</param>
        /// <param name="AY">Y-coordinate</param>
        void AddSuccessor(ArrayList ASuccessors, int AX, int AY)
        {
            int CurrentCost = StartPath.GetMap(AX, AY);

            if (CurrentCost == -1)
            {
                return;
            }
            AStarNode2D NewNode = new AStarNode2D(this, GoalNode, Cost + CurrentCost, AX, AY);

            if (NewNode.IsSameState(Parent))
            {
                return;
            }
            ASuccessors.Add(NewNode);
        }
        static void Main(string[] args)
        {
            Console.WriteLine("Starting...");

            AStar astar = new AStar();

            AStarNode2D GoalNode  = new AStarNode2D(null, null, 0, 9, 9);
            AStarNode2D StartNode = new AStarNode2D(null, GoalNode, 0, 0, 0)
            {
                GoalNode = GoalNode
            };

            astar.FindPath(StartNode, GoalNode);

            PrintSolution(astar.Solution);
            Console.ReadLine();
        }
Exemplo n.º 4
0
        public static List<string> Path(int startx, int starty, int endx, int endy, int endz, int csx, int csy)
        {
            // Here is where we come in from BotMe with our start and end points from the world
            AStar astar = new AStar();

            AStarNode2D GoalNode = new AStarNode2D(null, null, 0, endx, endy);
            AStarNode2D StartNode = new AStarNode2D(null, GoalNode, 0, startx, starty) {GoalNode = GoalNode};

            // Prepare the final List that will become the waypoints for him to leaf through
            List<string> botPoint = new List<string>();

            // Go get the solution
            astar.FindPath(StartNode, GoalNode);

            // First check if the path was possible
            bool pathDone = astar.PathPossible;
            if (!pathDone)
            {
                //Use botPoint List as a flag to break out of this. Return to Botme
                botPoint.Add("no_path");
                return botPoint;
            }

            // Slope calculation data
            int slope = 99; // Use 99 here to mean the slope has never been calculated yet
            int lastSlope = 99;
            int X1 = startx; //startx
            int Y1 = starty; //starty
            int Z = endz;
            //startz - we need this to make a vector but will override with current z in Botme enabling him to walk up hills

            int xtemp = 0;
            int ytemp = 0;

            // This gets the solution from Astar.cs and runs it through PrintInfo which has the xyz of each path node - our Node solution
            ArrayList Nodes = new ArrayList(astar.Solution);
            foreach (AStarNode nn in Nodes)
            {
                AStarNode2D n = (AStarNode2D) nn;
                // Return x and y from printinfo
                int[] XYreturn = new int[2];
                XYreturn = n.PrintNodeInfo();
                int X2 = XYreturn[0];
                int Y2 = XYreturn[1];

                // Here I calculate point only where the line changes direction
                // In this way the bot doesn't start and stop each step
                // Since it has been determined that the path is clear between these points this will work
                // You can see the trouble with moving objects here though - he will have to constantly check on the way to these points
                // To detect scene changes.
                slope = CalcSlope(Y2, Y1, X2, X1);

                if (lastSlope != slope)
                {
                    // Build the list of waypoints only where changes of slope occur
                    xtemp = X1 + csx; //conerStone x and y from our map to get these into sim coordinates
                    ytemp = Y1 + csy;
                    string temp = xtemp + "," + ytemp + "," + Z;
                    botPoint.Add(temp);
                }
                X1 = X2;
                Y1 = Y2;
                lastSlope = slope;
            }
            // This adds the last point to the step
            xtemp = X1 + csx;
            ytemp = Y1 + csy;
            string temp2 = xtemp + "," + ytemp + "," + Z;
            botPoint.Add(temp2);
            // This removes the first point of the steps so they turn and go right to the first bend point(slope)
            botPoint.RemoveRange(0, 1);
            // Let em have it - return to Botme path with slopes only no start point but with end point always
            return botPoint;
        }
Exemplo n.º 5
0
 /// <summary>
 ///     Adds a successor to a list if it is not impassible or the parent node
 /// </summary>
 /// <param name="aSuccessors">List of successors</param>
 /// <param name="aX">X-coordinate</param>
 /// <param name="aY">Y-coordinate</param>
 void AddSuccessor(ArrayList aSuccessors, int aX, int aY)
 {
     int CurrentCost = StartPath.GetMap(aX, aY);
     if (CurrentCost == -1)
     {
         return;
     }
     AStarNode2D NewNode = new AStarNode2D(this, GoalNode, Cost + CurrentCost, aX, aY);
     if (NewNode.IsSameState(Parent))
     {
         return;
     }
     aSuccessors.Add(NewNode);
 }
 /// <summary>
 ///     Prints the solution
 /// </summary>
 /// <param name="ASolution">The list that holds the solution</param>
 public static void PrintSolution(ArrayList ASolution)
 {
     for (int j = 0; j < 10; j++)
     {
         for (int i = 0; i < 10; i++)
         {
             bool solution = false;
             foreach (AStarNode2D n in ASolution)
             {
                 AStarNode2D tmp = new AStarNode2D(null, null, 0, i, j);
                 solution = n.IsSameState(tmp);
                 if (solution)
                     break;
             }
             if (solution)
                 Console.Write("S ");
             else if (GetMap(i, j) == -1)
                 Console.Write("X ");
             else
                 Console.Write(". ");
         }
         Console.WriteLine("");
     }
 }
        static void Main(string[] args)
        {
            Console.WriteLine("Starting...");

            AStar astar = new AStar();

            AStarNode2D GoalNode = new AStarNode2D(null, null, 0, 9, 9);
            AStarNode2D StartNode = new AStarNode2D(null, GoalNode, 0, 0, 0) {GoalNode = GoalNode};
            astar.FindPath(StartNode, GoalNode);

            PrintSolution(astar.Solution);
            Console.ReadLine();
        }
        public static List <string> Path(int startx, int starty, int endx, int endy, int endz, int csx, int csy)
        {
            // Here is where we come in from BotMe with our start and end points from the world
            AStar astar = new AStar();

            AStarNode2D GoalNode  = new AStarNode2D(null, null, 0, endx, endy);
            AStarNode2D StartNode = new AStarNode2D(null, GoalNode, 0, startx, starty)
            {
                GoalNode = GoalNode
            };

            // Prepare the final List that will become the waypoints for him to leaf through
            List <string> botPoint = new List <string>();


            // Go get the solution
            astar.FindPath(StartNode, GoalNode);

            // First check if the path was possible
            bool pathDone = astar.pathPossible;

            if (pathDone == false)
            {
                //Use botPoint List as a flag to break out of this. Return to Botme
                botPoint.Add("no_path");
                return(botPoint);
            }

            // Slope calculation data
            int slope     = 99;     // Use 99 here to mean the slope has never been calculated yet
            int lastSlope = 99;
            int X1        = startx; //startx
            int Y1        = starty; //starty
            int Z         = endz;
            //startz - we need this to make a vector but will override with current z in Botme enabling him to walk up hills

            int xtemp = 0;
            int ytemp = 0;


            // This gets the solution from Astar.cs and runs it through PrintInfo which has the xyz of each path node - our Node solution
            ArrayList Nodes = new ArrayList(astar.Solution);

            foreach (AStarNode nn in Nodes)
            {
                AStarNode2D n = (AStarNode2D)nn;
                // Return x and y from printinfo
                int[] XYreturn = new int[2];
                XYreturn = n.PrintNodeInfo();
                int X2 = XYreturn[0];
                int Y2 = XYreturn[1];

                // Here I calculate point only where the line changes direction
                // In this way the bot doesn't start and stop each step
                // Since it has been determined that the path is clear between these points this will work
                // You can see the trouble with moving objects here though - he will have to constantly check on the way to these points
                // To detect scene changes.
                slope = calcSlope(Y2, Y1, X2, X1);

                if (lastSlope != slope)
                {
                    // Build the list of waypoints only where changes of slope occur
                    xtemp = X1 + csx; //conerStone x and y from our map to get these into sim coordinates
                    ytemp = Y1 + csy;
                    string temp = xtemp.ToString() + "," + ytemp.ToString() + "," + Z.ToString();
                    botPoint.Add(temp);
                }
                X1        = X2;
                Y1        = Y2;
                lastSlope = slope;
            }
            // This adds the last point to the step
            xtemp = X1 + csx;
            ytemp = Y1 + csy;
            string temp2 = xtemp.ToString() + "," + ytemp.ToString() + "," + Z.ToString();

            botPoint.Add(temp2);
            // This removes the first point of the steps so they turn and go right to the first bend point(slope)
            botPoint.RemoveRange(0, 1);
            // Let em have it - return to Botme path with slopes only no start point but with end point always
            return(botPoint);
        }