/*
* Calculates the total cost of a node. It computes the total cost as the cost determine by
* the heuristic(calcHvalue) and the cost of the current path thus far(calcGvalue)
*/
public int calcFvalue(AstarNode node)
{
int ftemp;
ftemp = calcGvalue(node) + calcHvalue(node);
return(ftemp);
}
public bool findTargetNode(double x, double y)
{
//Generate nodes until we reach target, standard manhattan distance used to find it.
//check if the current generated node is the target node.
//determine quadrant in which the target lies
//generate the next node by using the next quadrant
AstarNode currentNode = startNode;
int direction;
while (true) //loop until we return...
{
if (isNodeTarget(currentNode, x, y))
{
targetNode = currentNode;
#if DEBUG
Globals.l2net_home.Add_Debug("Found Target Node:" + currentNode.xpos + " , " + currentNode.ypos);
#endif
nodelist.Clear();
nodelist.Add(targetNode);
return(true);
}
direction = getTargetDirection(currentNode, x, y);
if (direction < 0)
{
nodelist.Clear();
return(false);
}
currentNode = buildNode(currentNode, direction);
}
}
private bool isNodeIn(ArrayList list, AstarNode node)
{
foreach (AstarNode n in list)
{
if (n.xpos == node.xpos && n.ypos == node.ypos)
{
return(true);
}
}
return(false);
}
private bool checkPathForNode(AstarNode node)
{
for (int i = 0; i < pathNodes.Count; i++)
{
if (((AstarNode)pathNodes[i]).xpos == node.xpos && ((AstarNode)pathNodes[i]).ypos == node.ypos)
{
return(true);
}
}
return(false);
}
private int findMoveDirecton(AstarNode cur, AstarNode next)
{
int direction;
if (cur.xpos > next.xpos)
{
if (cur.ypos > next.ypos)
{
direction = NORTHWEST;
}
else if (cur.ypos < next.ypos)
{
direction = SOUTHWEST;
}
else
{
direction = WEST;
}
}
else if (cur.xpos < next.xpos)
{
if (cur.ypos > next.ypos)
{
direction = NORTHEAST;
}
else if (cur.ypos < next.ypos)
{
direction = SOUTHEAST;
}
else
{
direction = EAST;
}
}
else
{
if (cur.ypos > next.ypos)
{
direction = NORTH;
}
else if (cur.ypos < next.ypos)
{
direction = SOUTH;
}
else
{
direction = -1; //same node?
}
}
return(direction);
}
/* Here we are going to check for walls and see if they intersect any of our
* nodes, if they do we mark that node as unpassable so we can move around it
* We are going to check if either of the endpoints inside the node's box, if so
* then the wall is colliding. Next we are going to check for vertical collision on
* the vertical sides of the box, and horizontal collision on the horizontal sides
* of the box. If they collide then we set the current node to unpassable.
*
* This function returns FALSE if the node is NOT PASSABLE. TRUE if it IS
*
*/
public bool checkNodeWalls(AstarNode node)
{
for (int i = 0; i < Globals.gamedata.Walls.Count; i++)
{
// Globals.l2net_home.Add_Debug("Checking node:" + j);
//west wall
if (isIntersecting(node.x, node.y, node.x, node.y2,
((Wall)Globals.gamedata.Walls[i]).P1.X,
((Wall)Globals.gamedata.Walls[i]).P1.Y,
((Wall)Globals.gamedata.Walls[i]).P2.X,
((Wall)Globals.gamedata.Walls[i]).P2.Y))
{
return(false);
// Globals.l2net_home.Add_Debug("found intersetction west!");
}
//east wall
else if (isIntersecting(node.x2, node.y, node.x2, node.y2,
((Wall)Globals.gamedata.Walls[i]).P1.X,
((Wall)Globals.gamedata.Walls[i]).P1.Y,
((Wall)Globals.gamedata.Walls[i]).P2.X,
((Wall)Globals.gamedata.Walls[i]).P2.Y))
{
return(false);
// Globals.l2net_home.Add_Debug("found intersetction east!");
}
//north wall
else if (isIntersecting(node.x, node.y, node.x2, node.y,
((Wall)Globals.gamedata.Walls[i]).P1.X,
((Wall)Globals.gamedata.Walls[i]).P1.Y,
((Wall)Globals.gamedata.Walls[i]).P2.X,
((Wall)Globals.gamedata.Walls[i]).P2.Y))
{
return(false);
// Globals.l2net_home.Add_Debug("found intersetction! north");
}
//south wall
else if (isIntersecting(node.x, node.y2, node.x2, node.y2,
((Wall)Globals.gamedata.Walls[i]).P1.X,
((Wall)Globals.gamedata.Walls[i]).P1.Y,
((Wall)Globals.gamedata.Walls[i]).P2.X,
((Wall)Globals.gamedata.Walls[i]).P2.Y))
{
return(false);
// Globals.l2net_home.Add_Debug("found intersetction! south");
}
}
return(true);
}
public void expand(AstarNode parent)
{
AstarNode tmpNode;
tmpNode = buildNode(parent, NORTH);
tmpNode.parent = parent;
//parent.adjacentNodes.Add(tmpNode);
insertSorted(parent.adjacentNodes, tmpNode);
tmpNode = buildNode(parent, SOUTH);
tmpNode.parent = parent;
// parent.adjacentNodes.Add(tmpNode);
insertSorted(parent.adjacentNodes, tmpNode);
tmpNode = buildNode(parent, EAST);
tmpNode.parent = parent;
// parent.adjacentNodes.Add(tmpNode);
insertSorted(parent.adjacentNodes, tmpNode);
tmpNode = buildNode(parent, WEST);
tmpNode.parent = parent;
// parent.adjacentNodes.Add(tmpNode);
insertSorted(parent.adjacentNodes, tmpNode);
tmpNode = buildNode(parent, NORTHWEST);
tmpNode.parent = parent;
tmpNode.diagonal = true;
// parent.adjacentNodes.Add(tmpNode);
insertSorted(parent.adjacentNodes, tmpNode);
tmpNode = buildNode(parent, SOUTHWEST);
tmpNode.parent = parent;
tmpNode.diagonal = true;
//parent.adjacentNodes.Add(tmpNode);
insertSorted(parent.adjacentNodes, tmpNode);
tmpNode = buildNode(parent, NORTHEAST);
tmpNode.parent = parent;
tmpNode.diagonal = true;
// parent.adjacentNodes.Add(tmpNode);
insertSorted(parent.adjacentNodes, tmpNode);
tmpNode = buildNode(parent, SOUTHEAST);
tmpNode.parent = parent;
tmpNode.diagonal = true;
// parent.adjacentNodes.Add(tmpNode);
insertSorted(parent.adjacentNodes, tmpNode);
}
/*Iterative Deepining Search A*
* This function performs a basic depth first search with a depth limit provided by the minimum of
* the costs of the potential siblings. Additionally it orders the children it searchs in best first
* order. It has linear space and memory complexity. */
public bool IDAStar(AstarNode node)
{
int bound = 50;
while (bound > 0)
{
#if DEBUG
Globals.l2net_home.Add_Debug("updated bound:" + bound);
#endif
bound = DFS(node, bound);
// if (bound == INFINITY)
// return false;
//DFS(node, bound);
//bound += HorizontalCost;
}
return(true);
}
private bool isNodeTarget(AstarNode node, double targetX, double targetY)
{
if (targetX >= node.x)
{
if (targetX <= node.x2)
{
if (targetY >= node.y)
{
if (targetY <= node.y2)
{
return(true);
}
}
}
}
return(false);
}
private void buildPathFromParents(AstarNode goal)
{
#if DEBUG
Globals.l2net_home.Add_Debug("getting path...");
#endif
AstarNode tempNode = goal;
pathNodes.Clear();
Globals.debugPath = pathNodes;
while (tempNode.parent != null)
{
pathNodes.Add(tempNode);
tempNode = tempNode.parent;
}
pathNodes.Reverse();
return;
}
public AstarNode buildNode(AstarNode parent, int direction)
{
AstarNode tmpNode;
switch (direction)
{
case NORTH:
tmpNode = allocNode(parent.x, parent.y - gridSize, parent.xpos, parent.ypos - 1);
break;
case SOUTH:
tmpNode = allocNode(parent.x, parent.y + gridSize, parent.xpos, parent.ypos + 1);
break;
case EAST:
tmpNode = allocNode(parent.x + gridSize, parent.y, parent.xpos + 1, parent.ypos);
break;
case WEST:
tmpNode = allocNode(parent.x - gridSize, parent.y, parent.xpos - 1, parent.ypos);
break;
case NORTHEAST:
tmpNode = allocNode(parent.x + gridSize, parent.y - gridSize, parent.xpos + 1, parent.ypos - 1);
break;
case NORTHWEST:
tmpNode = allocNode(parent.x - gridSize, parent.y - gridSize, parent.xpos - 1, parent.ypos - 1);
break;
case SOUTHEAST:
tmpNode = allocNode(parent.x + gridSize, parent.y + gridSize, parent.xpos + 1, parent.ypos + 1);
break;
case SOUTHWEST:
tmpNode = allocNode(parent.x - gridSize, parent.y + gridSize, parent.xpos - 1, parent.ypos + 1);
break;
default:
tmpNode = null;
break;
}
return(tmpNode);
}
/*
* H-value stand for heuristic and is a 'guess' to how far away
* we are from the target. It is calculated by counting the number
* of squares we are away from the target in both the X and Y direction
* not counting diagonal directions. Then multiplying by our horizontal
* move cost(in this case its 10)
*/
public int calcHvalue(AstarNode node)
{
int tempX, tempY, tempH, moveCount = 0;
tempX = node.xpos;
while (targetNode.xpos != tempX)
{
if (targetNode.xpos > tempX) //test for right side of target node
{
tempX++;
}
if (targetNode.xpos < tempX) //test for left side of target node
{
tempX--;
}
moveCount++;
}
tempY = node.ypos;
while (targetNode.ypos != tempY)
{
if (targetNode.ypos > tempY)
{
tempY++;
}
if (targetNode.ypos < tempY)
{
tempY--;
}
moveCount++;
}
tempH = moveCount * HorizontalCost;
node.hvalue = tempH;
return(tempH);
}
private int getTargetDirection(AstarNode node, double targetX, double targetY)
{
int direction;
if (targetX >= node.x)
{
if (targetX <= node.x2)
{
//in correct x ... let next section modify direction...
direction = -1;
}
else
{
direction = EAST;
}
}
else
{
direction = WEST;
}
if (targetY >= node.y)
{
if (targetY <= node.y2)
{
//do nothing... we are in correct Y direction
}
else
{
direction = SOUTH;
}
}
else
{
direction = NORTH;
}
//this shouldn't happen
// Globals.l2net_home.Add_Debug("x:"+node.x+" tx:"+targetX+" x2:"+node.x2+" y:"+node.y+" ty:"+targetY+" y2:"+node.y2);
return(direction);
}
/* G-value is the cost of moving from the starting node to its current location
* it includes diagonal and horizontal movement. It is calculated by adding horizontalCost
* or diagonalcost to it's parent's G-value. Each node has a 'parent' node that will
* eventually point back to the starting location */
public int calcGvalue(AstarNode node)
{
if (node.getParent() == null)
{
node.gvalue = 0;
return(0);
}
else
{
if (node.diagonal)
{
node.gvalue = node.getParent().gvalue + DiagonalCost;
}
else
{
node.gvalue = (node.getParent().gvalue + (HorizontalCost));
}
return(node.gvalue);
}
}
private void insertSorted(ArrayList list, AstarNode node)
{
node.fvalue = calcFvalue(node);
// bool inserted = false;
int i = 0;
if (list.Count == 0)
{
list.Add(node);
}
else
{
for (i = 0; i < list.Count; i++)
{
if (node.fvalue > ((AstarNode)list[i]).fvalue)
{
break;
}
}
list.Insert(i, node);
}
}
/*
* Returns true if the supplied node is an adjacent node on the current path list
*/
private bool checkPathAdjacentNode(AstarNode node)
{
for (int i = 0; i < pathNodes.Count - 1; i++)
{
for (int j = 0; j < ((AstarNode)pathNodes[i]).adjacentNodes.Count; j++)
{
if (isNodeTarget((AstarNode)((AstarNode)pathNodes[i]).adjacentNodes[j], targetNode.x, targetNode.y))
{
#if DEBUG
Globals.l2net_home.Add_Debug("Found target node as adjacent to path...");
#endif
return(true);
}
if (((AstarNode)((AstarNode)pathNodes[i]).adjacentNodes[j]).xpos == node.xpos &&
((AstarNode)((AstarNode)pathNodes[i]).adjacentNodes[j]).ypos == node.ypos)
{
return(true);
}
}
}
return(false);
}
public AstarNode Clone()
{
AstarNode tmpNode = new AstarNode();
tmpNode.x = this.x; //upper left corner
tmpNode.y = this.y;
tmpNode.x2 = this.x2;
tmpNode.y2 = this.y2;
tmpNode.cx = this.cx;
tmpNode.cy = this.cy;
tmpNode.xpos = this.xpos;
tmpNode.ypos = this.ypos;
tmpNode.passable = this.passable;
tmpNode.fvalue = this.fvalue;
tmpNode.hvalue = this.hvalue;
tmpNode.gvalue = this.gvalue;
tmpNode.parent = this.parent;
tmpNode.adjacentNodes = (System.Collections.ArrayList) this.adjacentNodes.Clone();
tmpNode.children = (System.Collections.ArrayList) this.children.Clone();
tmpNode.diagonal = this.diagonal;
return(tmpNode);
}
public AstarNode allocNode(double X, double Y, int Xpos, int Ypos)
{
try
{
AstarNode tmpNode = new AstarNode();
tmpNode.x = X;
tmpNode.y = Y;
tmpNode.x2 = X + this.gridSize;
tmpNode.y2 = Y + this.gridSize;
tmpNode.xpos = Xpos;
tmpNode.ypos = Ypos;
tmpNode.passable = checkNodeWalls(tmpNode);
tmpNode.calcMidPoint();
// nodelist.Add(tmpNode); nodelist is now only useful for debugging...
return(tmpNode);
}
catch (Exception e)
{
Globals.l2net_home.Add_Error("ERROR:" + e.Message);
}
return(null);
}
public AstarNode Clone()
{
AstarNode tmpNode = new AstarNode();
tmpNode.x = this.x; //upper left corner
tmpNode.y = this.y;
tmpNode.x2 = this.x2;
tmpNode.y2 = this.y2;
tmpNode.cx = this.cx;
tmpNode.cy = this.cy;
tmpNode.xpos = this.xpos;
tmpNode.ypos = this.ypos;
tmpNode.passable = this.passable;
tmpNode.fvalue = this.fvalue;
tmpNode.hvalue = this.hvalue;
tmpNode.gvalue = this.gvalue;
tmpNode.parent = this.parent;
tmpNode.adjacentNodes = (System.Collections.ArrayList)this.adjacentNodes.Clone();
tmpNode.children = (System.Collections.ArrayList)this.children.Clone();
tmpNode.diagonal = this.diagonal;
return tmpNode;
}
/*
* Returns true if the supplied node is an adjacent node on the current path list
*/
private bool checkPathAdjacentNode(AstarNode node)
{
for(int i = 0; i < pathNodes.Count-1; i++)
{
for(int j = 0; j < ((AstarNode)pathNodes[i]).adjacentNodes.Count; j++)
{
if (isNodeTarget(((AstarNode)((AstarNode)pathNodes[i]).adjacentNodes[j]), targetNode.x, targetNode.y))
{
#if DEBUG
Globals.l2net_home.Add_Debug("Found target node as adjacent to path...");
#endif
return true;
}
if(((AstarNode)((AstarNode)pathNodes[i]).adjacentNodes[j]).xpos == node.xpos &&
((AstarNode)((AstarNode)pathNodes[i]).adjacentNodes[j]).ypos == node.ypos)
return true;
}
}
return false;
}
/* Standard A* */
public bool Astar_start(AstarNode startNode, AstarNode targetNode)
{
ArrayList closedlist = new ArrayList();
ArrayList openlist = new ArrayList();
closedlist.Clear();
openlist.Clear();
startNode.fvalue = calcFvalue(startNode); //this sets g and h
openlist.Add(startNode);
while (openlist.Count > 0)
{
Globals.debugPath = pathNodes;
AstarNode xNode;
openlist.Sort();
xNode = (AstarNode)openlist[0];
if (xNode == targetNode)
{
pathNodes.Add(xNode);
return(true);
}
openlist.Remove(xNode);
closedlist.Add(xNode);
pathNodes.Add(xNode);
findAdjacentNodes(xNode);
foreach (AstarNode yNode in xNode.adjacentNodes)
{
if (closedlist.Contains(yNode))
{
continue;
}
int tempGScore;
bool isBetter = false;
//todo add diagonals.
tempGScore = xNode.gvalue + HorizontalCost;
yNode.fvalue = calcFvalue(yNode);
if (openlist.Contains(yNode))
{
openlist.Add(yNode);
isBetter = true;
}
else if (tempGScore < yNode.gvalue)
{
isBetter = true;
}
else
{
isBetter = false;
}
if (isBetter)
{
yNode.gvalue = tempGScore;
yNode.hvalue = calcHvalue(yNode);
yNode.fvalue = yNode.gvalue + yNode.hvalue;
}
}
}
return(false);
}
public fringePair(int gcost, AstarNode p)
{
this.g = gcost;
this.parent = p;
}
/* G-value is the cost of moving from the starting node to its current location
* it includes diagonal and horizontal movement. It is calculated by adding horizontalCost
* or diagonalcost to it's parent's G-value. Each node has a 'parent' node that will
* eventually point back to the starting location */
public int calcGvalue(AstarNode node)
{
if (node.getParent() == null)
{
node.gvalue = 0;
return 0;
}
else
{
if(node.diagonal)
node.gvalue = node.getParent().gvalue + DiagonalCost;
else
node.gvalue = (node.getParent().gvalue + (HorizontalCost));
return node.gvalue;
}
}
/*
* Calculates the total cost of a node. It computes the total cost as the cost determine by
* the heuristic(calcHvalue) and the cost of the current path thus far(calcGvalue)
*/
public int calcFvalue(AstarNode node)
{
int ftemp;
ftemp = calcGvalue(node) + (calcHvalue(node));
return ftemp;
}
private void insertSorted(System.Collections.ArrayList list, AstarNode node)
{
node.fvalue = calcFvalue(node);
// bool inserted = false;
int i = 0;
if (list.Count == 0)
list.Add(node);
else
{
for (i = 0; i < list.Count; i++)
{
if (node.fvalue > ((AstarNode)list[i]).fvalue)
{
break;
}
}
list.Insert(i, node);
}
}
/* Standard A* */
public bool Astar_start(AstarNode startNode, AstarNode targetNode)
{
System.Collections.ArrayList closedlist = new System.Collections.ArrayList();
System.Collections.ArrayList openlist = new System.Collections.ArrayList();
closedlist.Clear();
openlist.Clear();
startNode.fvalue = calcFvalue(startNode); //this sets g and h
openlist.Add(startNode);
while (openlist.Count > 0)
{
Globals.debugPath = pathNodes;
AstarNode xNode;
openlist.Sort();
xNode = ((AstarNode)openlist[0]);
if (xNode == targetNode)
{
pathNodes.Add(xNode);
return true;
}
openlist.Remove(xNode);
closedlist.Add(xNode);
pathNodes.Add(xNode);
findAdjacentNodes(xNode);
foreach (AstarNode yNode in xNode.adjacentNodes)
{
if (closedlist.Contains(yNode))
continue;
int tempGScore;
bool isBetter = false;
//todo add diagonals.
tempGScore = xNode.gvalue + HorizontalCost;
yNode.fvalue = calcFvalue(yNode);
if (openlist.Contains(yNode))
{
openlist.Add(yNode);
isBetter = true;
}
else if (tempGScore < yNode.gvalue)
isBetter = true;
else
isBetter = false;
if (isBetter)
{
yNode.gvalue = tempGScore;
yNode.hvalue = calcHvalue(yNode);
yNode.fvalue = yNode.gvalue + yNode.hvalue;
}
}
}
return false;
}
public AstarNode buildNode(AstarNode parent, int direction)
{
AstarNode tmpNode;
switch (direction)
{
case NORTH:
tmpNode = allocNode(parent.x, parent.y - gridSize, parent.xpos, parent.ypos - 1);
break;
case SOUTH:
tmpNode = allocNode(parent.x, parent.y + gridSize, parent.xpos, parent.ypos + 1);
break;
case EAST:
tmpNode = allocNode(parent.x + gridSize, parent.y, parent.xpos + 1, parent.ypos);
break;
case WEST:
tmpNode = allocNode(parent.x - gridSize, parent.y, parent.xpos - 1, parent.ypos);
break;
case NORTHEAST:
tmpNode = allocNode(parent.x + gridSize, parent.y - gridSize, parent.xpos + 1, parent.ypos - 1);
break;
case NORTHWEST:
tmpNode = allocNode(parent.x - gridSize, parent.y - gridSize, parent.xpos - 1, parent.ypos - 1);
break;
case SOUTHEAST:
tmpNode = allocNode(parent.x + gridSize, parent.y + gridSize, parent.xpos + 1, parent.ypos + 1);
break;
case SOUTHWEST:
tmpNode = allocNode(parent.x - gridSize, parent.y + gridSize, parent.xpos - 1, parent.ypos + 1);
break;
default:
tmpNode = null;
break;
}
return tmpNode;
}
public AstarNode allocNode(double X, double Y, int Xpos, int Ypos)
{
try
{
AstarNode tmpNode = new AstarNode();
tmpNode.x = X;
tmpNode.y = Y;
tmpNode.x2 = X + this.gridSize;
tmpNode.y2 = Y + this.gridSize;
tmpNode.xpos = Xpos;
tmpNode.ypos = Ypos;
tmpNode.passable = checkNodeWalls(tmpNode);
tmpNode.calcMidPoint();
// nodelist.Add(tmpNode); nodelist is now only useful for debugging...
return tmpNode;
}
catch(Exception e)
{
Globals.l2net_home.Add_Error("ERROR:" + e.Message);
}
return null;
}
public fringePair(int gcost, AstarNode p)
{
this.g = gcost;
this.parent = p;
}
public void findAdjacentNodes(AstarNode node)
{
AstarNode tmpNodePtr;
if (node.adjacentNodes.Count != 0)
{
return; //we already have found our adjacent nodes...
}
//horizontal nodes
//north
tmpNodePtr = getNode(node.xpos, node.ypos - 1);
if (tmpNodePtr == null)
{
tmpNodePtr = buildNode(node, NORTH);
}
else
{
tmpNodePtr.ivalue += 1;
}
tmpNodePtr.parent = node;
node.adjacentNodes.Add(tmpNodePtr);
//south
tmpNodePtr = getNode(node.xpos, node.ypos + 1);
if (tmpNodePtr == null)
{
tmpNodePtr = buildNode(node, SOUTH);
}
else
{
tmpNodePtr.ivalue += 1;
}
tmpNodePtr.parent = node;
node.adjacentNodes.Add(tmpNodePtr);
//east
tmpNodePtr = getNode(node.xpos + 1, node.ypos);
if (tmpNodePtr == null)
{
tmpNodePtr = buildNode(node, EAST);
}
else
{
tmpNodePtr.ivalue += 1;
}
tmpNodePtr.parent = node;
node.adjacentNodes.Add(tmpNodePtr);
//west
tmpNodePtr = getNode(node.xpos - 1, node.ypos);
if (tmpNodePtr == null)
{
tmpNodePtr = buildNode(node, WEST);
}
else
{
tmpNodePtr.ivalue += 1;
}
tmpNodePtr.parent = node;
node.adjacentNodes.Add(tmpNodePtr);
//Diagonal nodes
//nw
tmpNodePtr = getNode(node.xpos - 1, node.ypos - 1);
if (tmpNodePtr == null)
{
tmpNodePtr = buildNode(node, NORTHWEST);
}
else
{
tmpNodePtr.ivalue += 1;
}
tmpNodePtr.parent = node;
tmpNodePtr.diagonal = true;
node.adjacentNodes.Add(tmpNodePtr);
//sw
tmpNodePtr = getNode(node.xpos - 1, node.ypos + 1);
if (tmpNodePtr == null)
{
tmpNodePtr = buildNode(node, SOUTHWEST);
}
else
{
tmpNodePtr.ivalue += 1;
}
tmpNodePtr.diagonal = true;
node.adjacentNodes.Add(tmpNodePtr);
//ne
tmpNodePtr = getNode(node.xpos + 1, node.ypos - 1);
if (tmpNodePtr == null)
{
tmpNodePtr = buildNode(node, NORTHEAST);
}
else
{
tmpNodePtr.ivalue += 1;
}
tmpNodePtr.diagonal = true;
tmpNodePtr.parent = node;
node.adjacentNodes.Add(tmpNodePtr);
//se
tmpNodePtr = getNode(node.xpos + 1, node.ypos + 1);
if (tmpNodePtr == null)
{
tmpNodePtr = buildNode(node, SOUTHEAST);
}
else
{
tmpNodePtr.ivalue += 1;
}
tmpNodePtr.diagonal = true;
tmpNodePtr.parent = node;
node.adjacentNodes.Add(tmpNodePtr);
}
/* Depth First Search Function */
private int DFS(AstarNode node, int bound)
{
node.fvalue = calcFvalue(node);
if (node.fvalue > bound)
{
return(node.fvalue);
}
pathNodes.Add(node);
Globals.debugPath = pathNodes;
if (calcHvalue(node) == 0)
{
return(0); //Goal found?
}
if (isNodeTarget(node, targetNode.x, targetNode.y))
{
return(0); //goal?!
}
//get children
node.adjacentNodes.Clear();
//expand(node);
findAdjacentNodes(node); //we might be able to get away with this instead...
//calc F value for each child
foreach (AstarNode n in node.adjacentNodes)
{
n.fvalue = calcFvalue(n);
}
//sort adjacent nodes so we have a best first search ....
// node.adjacentNodes.Sort();
int min = INFINITY;
// AstarNode minNode;
foreach (AstarNode n in node.adjacentNodes)
{
// ignore child if its a wall
if (n.passable)
{
//also ignore child if it is already on our path, or if its a child of a node on our path.
//note, these functions check xpos and ypos NOT node objects.
if (!checkPathForNode(n) && !checkPathAdjacentNode(n))
// if(!checkPathForNode(n))
{
int temp;
temp = DFS(n, bound);
if (temp == 0)
{
return(0); //we wont get any lower than 0
}
if (temp == INFINITY)
{
//This child has no children worth looking at...
}
if (min > temp)
{
// Globals.debugNode = n;
min = temp;
}
/* if (temp != INFINITY && min == temp)
* {
* Globals.debugNode2 = n;
* Globals.l2net_home.Add_Debug("n1(" + min + "):" + Globals.debugNode + " n2(" + temp + "):" + Globals.debugNode2);
* System.Threading.Thread.Sleep(2000);
* //return 0;
* }
* else
* System.Threading.Thread.Sleep(200);*/
}
}
}
if (min == INFINITY)
{
// Globals.debugNode3 = node;
// System.Threading.Thread.Sleep(1000);
// Globals.l2net_home.Add_Debug("WTF");
}
else if (min >= bound)
{
pathNodes.Remove(node);
return(bound);
}
pathNodes.Remove(node);
return(min);
}
/*Iterative Deepining Search A*
* This function performs a basic depth first search with a depth limit provided by the minimum of
* the costs of the potential siblings. Additionally it orders the children it searchs in best first
* order. It has linear space and memory complexity. */
public bool IDAStar(AstarNode node)
{
int bound = 50;
while (bound > 0)
{
#if DEBUG
Globals.l2net_home.Add_Debug("updated bound:" + bound);
#endif
bound = DFS(node, bound);
// if (bound == INFINITY)
// return false;
//DFS(node, bound);
//bound += HorizontalCost;
}
return true;
}
/* Depth First Search Function */
private int DFS(AstarNode node, int bound)
{
node.fvalue = calcFvalue(node);
if (node.fvalue > bound)
return node.fvalue;
pathNodes.Add(node);
Globals.debugPath = pathNodes;
if (calcHvalue(node) == 0)
return 0; //Goal found?
if (isNodeTarget(node, targetNode.x, targetNode.y))
return 0; //goal?!
//get children
node.adjacentNodes.Clear();
//expand(node);
findAdjacentNodes(node); //we might be able to get away with this instead...
//calc F value for each child
foreach (AstarNode n in node.adjacentNodes)
n.fvalue = calcFvalue(n);
//sort adjacent nodes so we have a best first search ....
// node.adjacentNodes.Sort();
int min = INFINITY;
// AstarNode minNode;
foreach (AstarNode n in node.adjacentNodes)
{
// ignore child if its a wall
if (n.passable)
{
//also ignore child if it is already on our path, or if its a child of a node on our path.
//note, these functions check xpos and ypos NOT node objects.
if (!checkPathForNode(n) && !checkPathAdjacentNode(n))
// if(!checkPathForNode(n))
{
int temp;
temp = DFS(n, bound);
if (temp == 0)
return 0; //we wont get any lower than 0
if (temp == INFINITY)
{
//This child has no children worth looking at...
}
if (min > temp)
{
// Globals.debugNode = n;
min = temp;
}
/* if (temp != INFINITY && min == temp)
{
Globals.debugNode2 = n;
Globals.l2net_home.Add_Debug("n1(" + min + "):" + Globals.debugNode + " n2(" + temp + "):" + Globals.debugNode2);
System.Threading.Thread.Sleep(2000);
//return 0;
}
else
System.Threading.Thread.Sleep(200);*/
}
}
}
if (min == INFINITY)
{
// Globals.debugNode3 = node;
// System.Threading.Thread.Sleep(1000);
// Globals.l2net_home.Add_Debug("WTF");
}
else if (min >= bound)
{
pathNodes.Remove(node);
return bound;
}
pathNodes.Remove(node);
return min;
}
private bool isNodeTarget(AstarNode node, double targetX, double targetY)
{
if (targetX >= node.x)
{
if (targetX <= node.x2)
{
if (targetY >= node.y)
{
if (targetY <= node.y2)
{
return true;
}
}
}
}
return false;
}
private void buildPathFromParents(AstarNode goal)
{
#if DEBUG
Globals.l2net_home.Add_Debug("getting path...");
#endif
AstarNode tempNode = goal;
pathNodes.Clear();
Globals.debugPath = pathNodes;
while (tempNode.parent != null)
{
pathNodes.Add(tempNode);
tempNode = tempNode.parent;
}
pathNodes.Reverse();
return;
}
private int getTargetDirection(AstarNode node, double targetX, double targetY)
{
int direction;
if (targetX >= node.x)
{
if (targetX <= node.x2)
{
//in correct x ... let next section modify direction...
direction = -1;
}
else
{
direction = EAST;
}
}
else
{
direction = WEST;
}
if (targetY >= node.y)
{
if (targetY <= node.y2)
{
//do nothing... we are in correct Y direction
}
else
{
direction = SOUTH;
}
}
else
{
direction = NORTH;
}
//this shouldn't happen
// Globals.l2net_home.Add_Debug("x:"+node.x+" tx:"+targetX+" x2:"+node.x2+" y:"+node.y+" ty:"+targetY+" y2:"+node.y2);
return direction;
}
private bool isNodeIn(System.Collections.ArrayList list, AstarNode node)
{
foreach (AstarNode n in list)
{
if (n.xpos == node.xpos && n.ypos == node.ypos)
return true;
}
return false;
}
public void findAdjacentNodes(AstarNode node)
{
AstarNode tmpNodePtr;
if (node.adjacentNodes.Count != 0)
return; //we already have found our adjacent nodes...
//horizontal nodes
//north
tmpNodePtr = getNode(node.xpos, node.ypos - 1);
if (tmpNodePtr == null)
tmpNodePtr = buildNode(node, NORTH);
else
tmpNodePtr.ivalue += 1;
tmpNodePtr.parent = node;
node.adjacentNodes.Add(tmpNodePtr);
//south
tmpNodePtr = getNode(node.xpos, node.ypos + 1);
if (tmpNodePtr == null)
tmpNodePtr = buildNode(node, SOUTH);
else
tmpNodePtr.ivalue += 1;
tmpNodePtr.parent = node;
node.adjacentNodes.Add(tmpNodePtr);
//east
tmpNodePtr = getNode(node.xpos + 1, node.ypos);
if (tmpNodePtr == null)
tmpNodePtr = buildNode(node, EAST);
else
tmpNodePtr.ivalue += 1;
tmpNodePtr.parent = node;
node.adjacentNodes.Add(tmpNodePtr);
//west
tmpNodePtr = getNode(node.xpos - 1, node.ypos);
if (tmpNodePtr == null)
tmpNodePtr = buildNode(node, WEST);
else
tmpNodePtr.ivalue += 1;
tmpNodePtr.parent = node;
node.adjacentNodes.Add(tmpNodePtr);
//Diagonal nodes
//nw
tmpNodePtr = getNode(node.xpos - 1, node.ypos - 1);
if (tmpNodePtr == null)
tmpNodePtr = buildNode(node, NORTHWEST);
else
tmpNodePtr.ivalue += 1;
tmpNodePtr.parent = node;
tmpNodePtr.diagonal = true;
node.adjacentNodes.Add(tmpNodePtr);
//sw
tmpNodePtr = getNode(node.xpos - 1, node.ypos + 1);
if (tmpNodePtr == null)
tmpNodePtr = buildNode(node, SOUTHWEST);
else
tmpNodePtr.ivalue += 1;
tmpNodePtr.diagonal = true;
node.adjacentNodes.Add(tmpNodePtr);
//ne
tmpNodePtr = getNode(node.xpos + 1, node.ypos - 1);
if (tmpNodePtr == null)
tmpNodePtr = buildNode(node, NORTHEAST);
else
tmpNodePtr.ivalue += 1;
tmpNodePtr.diagonal = true;
tmpNodePtr.parent = node;
node.adjacentNodes.Add(tmpNodePtr);
//se
tmpNodePtr = getNode(node.xpos + 1, node.ypos + 1);
if (tmpNodePtr == null)
tmpNodePtr = buildNode(node, SOUTHEAST);
else
tmpNodePtr.ivalue += 1;
tmpNodePtr.diagonal = true;
tmpNodePtr.parent = node;
node.adjacentNodes.Add(tmpNodePtr);
}
/*
* H-value stand for heuristic and is a 'guess' to how far away
* we are from the target. It is calculated by counting the number
* of squares we are away from the target in both the X and Y direction
* not counting diagonal directions. Then multiplying by our horizontal
* move cost(in this case its 10)
*/
public int calcHvalue(AstarNode node)
{
int tempX, tempY, tempH, moveCount = 0;
tempX = node.xpos;
while (targetNode.xpos != tempX)
{
if (targetNode.xpos > tempX) //test for right side of target node
tempX++;
if (targetNode.xpos < tempX) //test for left side of target node
tempX--;
moveCount++;
}
tempY = node.ypos;
while(targetNode.ypos != tempY)
{
if(targetNode.ypos > tempY)
tempY++;
if(targetNode.ypos < tempY)
tempY--;
moveCount++;
}
tempH = moveCount * HorizontalCost;
node.hvalue = tempH;
return tempH;
}
public void expand(AstarNode parent)
{
AstarNode tmpNode;
tmpNode = buildNode(parent, NORTH);
tmpNode.parent = parent;
//parent.adjacentNodes.Add(tmpNode);
insertSorted(parent.adjacentNodes, tmpNode);
tmpNode = buildNode(parent, SOUTH);
tmpNode.parent = parent;
// parent.adjacentNodes.Add(tmpNode);
insertSorted(parent.adjacentNodes, tmpNode);
tmpNode = buildNode(parent, EAST);
tmpNode.parent = parent;
// parent.adjacentNodes.Add(tmpNode);
insertSorted(parent.adjacentNodes, tmpNode);
tmpNode = buildNode(parent, WEST);
tmpNode.parent = parent;
// parent.adjacentNodes.Add(tmpNode);
insertSorted(parent.adjacentNodes, tmpNode);
tmpNode = buildNode(parent, NORTHWEST);
tmpNode.parent = parent;
tmpNode.diagonal = true;
// parent.adjacentNodes.Add(tmpNode);
insertSorted(parent.adjacentNodes, tmpNode);
tmpNode = buildNode(parent, SOUTHWEST);
tmpNode.parent = parent;
tmpNode.diagonal = true;
//parent.adjacentNodes.Add(tmpNode);
insertSorted(parent.adjacentNodes, tmpNode);
tmpNode = buildNode(parent, NORTHEAST);
tmpNode.parent = parent;
tmpNode.diagonal = true;
// parent.adjacentNodes.Add(tmpNode);
insertSorted(parent.adjacentNodes, tmpNode);
tmpNode = buildNode(parent, SOUTHEAST);
tmpNode.parent = parent;
tmpNode.diagonal = true;
// parent.adjacentNodes.Add(tmpNode);
insertSorted(parent.adjacentNodes, tmpNode);
}
private int findMoveDirecton(AstarNode cur, AstarNode next)
{
int direction;
if (cur.xpos > next.xpos)
{
if (cur.ypos > next.ypos)
direction = NORTHWEST;
else if (cur.ypos < next.ypos)
direction = SOUTHWEST;
else
direction = WEST;
}
else if (cur.xpos < next.xpos)
{
if (cur.ypos > next.ypos)
direction = NORTHEAST;
else if (cur.ypos < next.ypos)
direction = SOUTHEAST;
else
direction = EAST;
}
else
{
if (cur.ypos > next.ypos)
direction = NORTH;
else if (cur.ypos < next.ypos)
direction = SOUTH;
else
direction = -1; //same node?
}
return direction;
}
/* Here we are going to check for walls and see if they intersect any of our
* nodes, if they do we mark that node as unpassable so we can move around it
* We are going to check if either of the endpoints inside the node's box, if so
* then the wall is colliding. Next we are going to check for vertical collision on
* the vertical sides of the box, and horizontal collision on the horizontal sides
* of the box. If they collide then we set the current node to unpassable.
*
* This function returns FALSE if the node is NOT PASSABLE. TRUE if it IS
*
*/
public bool checkNodeWalls(AstarNode node)
{
for (int i = 0; i < Globals.gamedata.Walls.Count; i++)
{
// Globals.l2net_home.Add_Debug("Checking node:" + j);
//west wall
if (isIntersecting(node.x, node.y,node.x, node.y2,
((Wall)Globals.gamedata.Walls[i]).P1.X,
((Wall)Globals.gamedata.Walls[i]).P1.Y,
((Wall)Globals.gamedata.Walls[i]).P2.X,
((Wall)Globals.gamedata.Walls[i]).P2.Y))
{
return false;
// Globals.l2net_home.Add_Debug("found intersetction west!");
}
//east wall
else if (isIntersecting(node.x2, node.y,node.x2, node.y2,
((Wall)Globals.gamedata.Walls[i]).P1.X,
((Wall)Globals.gamedata.Walls[i]).P1.Y,
((Wall)Globals.gamedata.Walls[i]).P2.X,
((Wall)Globals.gamedata.Walls[i]).P2.Y))
{
return false;
// Globals.l2net_home.Add_Debug("found intersetction east!");
}
//north wall
else if (isIntersecting(node.x, node.y,node.x2, node.y,
((Wall)Globals.gamedata.Walls[i]).P1.X,
((Wall)Globals.gamedata.Walls[i]).P1.Y,
((Wall)Globals.gamedata.Walls[i]).P2.X,
((Wall)Globals.gamedata.Walls[i]).P2.Y))
{
return false;
// Globals.l2net_home.Add_Debug("found intersetction! north");
}
//south wall
else if (isIntersecting(node.x, node.y2,node.x2, node.y2,
((Wall)Globals.gamedata.Walls[i]).P1.X,
((Wall)Globals.gamedata.Walls[i]).P1.Y,
((Wall)Globals.gamedata.Walls[i]).P2.X,
((Wall)Globals.gamedata.Walls[i]).P2.Y))
{
return false;
// Globals.l2net_home.Add_Debug("found intersetction! south");
}
}
return true;
}
private bool checkPathForNode(AstarNode node)
{
for (int i = 0; i < pathNodes.Count; i++)
{
if (((AstarNode)pathNodes[i]).xpos == node.xpos && ((AstarNode)pathNodes[i]).ypos == node.ypos)
return true;
}
return false;
}
/* Fringe Search
* Fringe search is a memory enchanced version of IDA* */
public bool fringeSearch()
{
//initialize:
ArrayList nowList = new ArrayList();
ArrayList laterList = new ArrayList();
ArrayList rejectedList = new ArrayList();
int limit = calcHvalue(startNode);
#if DEBUG
Globals.l2net_home.Add_Debug("start limit:" + limit);
#endif
bool found = false;
Globals.debugPath = nowList;
nowList.Add(startNode);
while (!found)
{
// Globals.l2net_home.Add_Debug("big loop...");
int fmin = INFINITY;
while (nowList.Count != 0)
{
AstarNode head = (AstarNode)nowList[0];
head.fvalue = calcFvalue(head);
#region check for goal
if (isNodeTarget(head, targetNode.x, targetNode.y))
{
found = true;
break;
}
#endregion
//check if head is over the limit
if (head.fvalue > limit)
{
//transfer head from nowlist to laterlist.
nowList.Remove(head);
laterList.Add(head);
//find the minimum of the nodes we will look at 'later'
fmin = Util.MIN(fmin, head.fvalue);
}
else
{
#region expand head's children on to now list
expand(head); //nodes are sorted by insert sort in this function
bool addedChildren = false;
foreach (AstarNode child in head.adjacentNodes)
{
//dont allow children already on path or adjacent to path or walls...
if (!isNodeIn(nowList, child) && !isNodeIn(laterList, child) && !isNodeIn(rejectedList, child))
{
if (child.passable == true)
{
//add child of head to front of nowlist
nowList.Insert(0, child);
addedChildren = true;
}
}
}
if (!addedChildren)
{
nowList.Remove(head);
rejectedList.Add(head);
}
#endregion
}
}
if (found == true)
{
break;
}
//set new limit
// Globals.l2net_home.Add_Debug("new limit:" + fmin);
limit = fmin;
//set now list to later list.
nowList = (ArrayList)laterList.Clone();
nowList.Sort();
Globals.debugPath = nowList;
laterList.Clear();
}
if (found == true)
{
#if DEBUG
Globals.l2net_home.Add_Debug("found a path... building...");
#endif
buildPathFromParents((AstarNode)nowList[0]);
return(true);
}
return(false);
}
