//return 0 if nothing found
//1 if agent/goal found
//2 if node on close list is found
/*
* doSearch method will run the A* search till a goal is found, or a node is in another agent closed list, or the
* nodes expanded is equal to the nodesToExpand variable
* Parameter: (int)nodesToExpand is the number of nodes that the search can expand
* (AIAgentAStarSearchListOp) secondSearchClosedList is the closed list from the other agent
* Return: (int)
* 0 if nothing was found
* 1 if the goal for this search agent was found
* 2 if a node on the second agent's closed list was found
*/
public int doSearch(int nodesToExpand, AIAgentAStarSearchNode[] secondSearchClosedList)
{
int nodesExpandedCount = 0;
while (openList.isEmpty() == false && nodesExpandedCount < nodesToExpand) //goes until nothing is left on the open list meaning a path could not be found
{
currentNode = openList.popNode(); //take the first(Best) polygon off the openList
nodesVisited++;
if (currentNode == null)
{
return(0);
}
closedList[currentNode.getPolygon().getID()] = currentNode;
if (isBackwards == true)
{
if (currentNode.getPolygon().getHasAgent() == true)
{
finalSolutionStart = currentNode;
return(1);
}
}
else
{
if (currentNode.getPolygon().getHasGoal() == true) //checks to see if the currentNode has the goal inside its polygon
{
finalSolutionStart = currentNode;
return(1);
}
}
if (secondSearchClosedList[currentNode.getPolygon().getID()] != null)
{
finalSolutionStart = currentNode;
return(2);
}
for (int count = 0; count < currentNode.getPolygon().getNeighborsHeld(); count++) //adds all the neighbors that are not on the closed list to the open list
{
if (closedList[currentNode.getPolygon().getNeighborAt(count)] == null)
{
gCost = (currentNode.getPolygon().getCenterVector() - polygonArray[currentNode.getPolygon().getNeighborAt(count)].getCenterVector()).magnitude + currentNode.getGFromStartingNode();
if (openList.isNodeOnList(polygonArray[currentNode.getPolygon().getNeighborAt(count)]) == false)
{
openList.addNode(polygonArray[currentNode.getPolygon().getNeighborAt(count)], currentNode, gCost);
}
else if (openList.getNodeOnList(polygonArray[currentNode.getPolygon().getNeighborAt(count)]).compareToG(gCost) > 0f) //updates the a Nodes information if the new GCost (cost from start to node) is less then what was previously in it
{
openList.updateNode(openList.getNodeOnList(polygonArray[currentNode.getPolygon().getNeighborAt(count)]), currentNode, gCost);
}
}
}
if (openList.getSize() > maxQueueSize)
{
maxQueueSize = openList.getSize();
}
nodesExpandedCount++;
}
return(0);
}
/*
* AIBiDirectionalAStartAgentOp's constructor will set up the initial values for instance variables
* Parameters: (Vector3)goalPositionToAdd is the position that the goal this search is looking for is at
* (AIPolygon[])polygonsToAdd is the array of polygons that it will search through
* (bool)isBackwardsToAdd is the bool to tell if this search is going from the goal or from the agent
*/
public AIBiDirectionalAStarAgentOp(Vector3 goalPositionToAdd, AIPolygon[] polygonsToAdd, bool isBackwardsToAdd)
{
polygonArray = polygonsToAdd;
goalPosition = goalPositionToAdd;
isBackwards = isBackwardsToAdd;
polygonFinalCount = 0;
maxQueueSize = 0;
nodesVisited = 0;
openList = new AIAgentAStarSearchListOp(goalPosition, polygonArray.Length);
closedList = new AIAgentAStarSearchNode[polygonArray.Length];
for (int count = 0; count < polygonArray.Length; count++)
{
closedList [count] = null;
}
if (isBackwards == true) //going from the goal
{
for (int count = 0; count < polygonArray.Length; count++) // looks for the polygon with the agent GameObject inside it
{
if (polygonArray [count].getHasGoal() == true)
{
openList.addNode(polygonArray [count], null, 0); //adds the first polygon to the openList
count = polygonArray.Length;
}
}
}
else //going from the agent
{
for (int count = 0; count < polygonArray.Length; count++) // looks for the polygon with the agent GameObject inside it
{
if (polygonArray [count].getHasAgent() == true)
{
openList.addNode(polygonArray [count], null, 0); //adds the first polygon to the openList
count = polygonArray.Length;
}
}
}
gCost = 0f;
}
/*
* searchStart method will begin the search by first setting the first node in the open list, which holds the
* polygon that has the agent GameObject in it, then it will call the functions to do the search, build the
* finalSolution array, and set the wayPoints
* Parameters: none
* Return: none
*/
public void startSearch()
{
openList = new AIAgentAStarSearchListOp(goalPosition, polygonArray.Length);
for (int count = 0; count < polygonArray.Length; count++) // looks for the polygon with the agent GameObject inside it
{
if (polygonArray [count].getHasAgent() == true && polygonArray[count].getAgentID() == 1)
{
openList.addNode(polygonArray [count], null, 0); //adds the first polygon to the openList
count = polygonArray.Length;
}
}
AStarSearch(); //does the AStar search
printFinalSolution(); //prints the finalSolution for debugging
addFinalSolutionPolygons(); //adds the finalsolution to the finalsolution array
}
/*
* AStarSearch method will preform an A* algorithm for searching a space to find a goal. It does this by taking the best
* polygon for the search off the openList, adding its neighbors to the openlist, placing the node on the closed list
* then repeating until it found a polygon that has the goal gameObject inside it
* Parameters: none
* Return: none
*/
void AStarSearch()
{
maxQueueSize = 1;
AIAgentAStarSearchNode currentNode;
float gCost = 0f;
bool[] closedList2 = new bool[polygonArray.Length]; //use to replace the close list to help reduce linear searches
for (int count = 0; count < polygonArray.Length; count++)
{
closedList2 [count] = false;
}
while (openList.isEmpty() == false) //goes until nothing is left on the open list meaning a path could not be found
{
currentNode = openList.popNode(); //take the first(Best) polygon off the openList
nodesVisited++;
if (currentNode == null)
{
return;
}
closedList2[currentNode.getPolygon().getID()] = true; //adds node to the close list
if (currentNode.getPolygon().getHasGoal() == true) //checks to see if the currentNode has the goal inside its polygon
{
finalSolutionStart = currentNode;
return;
}
for (int count = 0; count < currentNode.getPolygon().getNeighborsHeld(); count++) //adds all the neighbors that are not on the closed list to the open list
{
if (closedList2[currentNode.getPolygon().getNeighborAt(count)] == false) //checks to see if a node is logically should be in the closed list
{
gCost = (currentNode.getPolygon().getCenterVector() - polygonArray[currentNode.getPolygon().getNeighborAt(count)].getCenterVector()).magnitude + currentNode.getGFromStartingNode();
if (openList.isNodeOnList(polygonArray[currentNode.getPolygon().getNeighborAt(count)]) == false)
{
openList.addNode(polygonArray[currentNode.getPolygon().getNeighborAt(count)], currentNode, gCost);
}
else if (openList.getNodeOnList(polygonArray[currentNode.getPolygon().getNeighborAt(count)]).compareToG(gCost) > 0f) //updates the a Nodes information if the new GCost (cost from start to node) is less then what was previously in it
{
openList.updateNode(openList.getNodeOnList(polygonArray[currentNode.getPolygon().getNeighborAt(count)]), currentNode, gCost);
}
}
}
if (openList.getSize() > maxQueueSize)
{
maxQueueSize = openList.getSize();
}
}
}