//populate the cached path of the given AI with the path from startPoint to endPoint
private void GeneratePath(int aiAgentIndex, NodeIndex startPoint, NodeIndex endPoint, Node topLevelNode)
{
bool destinationWithinCurrentNode = startPoint.EqualAtDepth(endPoint, index.GetMaxDepth());
Node start = internalNodes[startPoint.GetIndexAtDepth(index.GetMaxDepth() + 1)];
Node end;
if (!destinationWithinCurrentNode)
{
end = topLevelNode.GetNode(endPoint);
}
else
{
end = internalNodes[endPoint.GetIndexAtDepth(index.GetMaxDepth() + 1)];
}
//If pathfinding in the lowest layer use the cheaper pathfinding method, else use A*
if (startPoint.GetMaxDepth() == index.GetMaxDepth() + 1)
{
lastPaths[aiAgentIndex] = Pathfinder.GetNextDestNode(start, end, internalNodes, topLevelNode);
}
else
{
lastPaths[aiAgentIndex] = Pathfinder.AstarPathfind(start, end, internalNodes);
}
}
//obtain the next node that the specified AI should move to
public Node GetNextDestination(int aiAgentIndex, Node currentPosition)
{
if (paths == null || paths.Count <= aiAgentIndex)
{
return(null);
}
if (paths[aiAgentIndex] == null || paths[aiAgentIndex].Count == 0)
{
return(null);
}
//if the current position is null, then the AI is not on any node. Return the start of the path.
if (currentPosition == null)
{
return(topLevelNode.GetNode(paths[aiAgentIndex][0]));
}
//if the AI is currently on a node, return the last node of the current rigidbody, or the first node of the next rigidbody
NodeIndex finalNodeOnCurrentRB = null;
for (int i = 0; i < paths[aiAgentIndex].Count; ++i)
{
if (finalNodeOnCurrentRB == null)
{
finalNodeOnCurrentRB = paths[aiAgentIndex][i];
}
else if (finalNodeOnCurrentRB.EqualAtDepth(paths[aiAgentIndex][i], finalNodeOnCurrentRB.GetMaxDepth() - 1))
{
finalNodeOnCurrentRB = paths[aiAgentIndex][i];
}
}
return(topLevelNode.GetNode(finalNodeOnCurrentRB));
}
//return the path from the start point to the destination point
public List <NodeIndex> GetPath(int aiAgentIndex, NodeIndex startPoint, NodeIndex endPoint, Node topLevelNode)
{
if (lastPaths == null || lastPaths.Count <= aiAgentIndex)
{
return(null);
}
if (startPoint == endPoint)
{
return(null);
}
//if the start and end point are both in the same child node, delegate to that child
int nextDepth = index.GetMaxDepth() + 1;
if (startPoint.EqualAtDepth(endPoint, nextDepth))
{
if (startPoint.GetIndexAtDepth(nextDepth) >= internalNodes.Count)
{
return(null);
}
if (startPoint.GetIndexAtDepth(nextDepth) < 0)
{
return(null);
}
return(internalNodes[startPoint.GetIndexAtDepth(nextDepth)].GetPath(aiAgentIndex, startPoint, endPoint, topLevelNode));
}
//if there is no cached path for the specified AI
if (lastPaths[aiAgentIndex] == null || lastPaths[aiAgentIndex].Count < 1 || lastDestinations[aiAgentIndex] != endPoint || lastOrigins[aiAgentIndex] != startPoint)
{
bool present = false;
//check the cached paths of the other AI's to see if any of them would be suitable
for (int i = 0; i < lastOrigins.Count; ++i)
{
if (i != aiAgentIndex && (lastOrigins[i] == startPoint) && (lastDestinations[i] == endPoint))
{
lastPaths[aiAgentIndex] = new List <NodeIndex>(lastPaths[i]);
lastOrigins[aiAgentIndex] = startPoint;
lastDestinations[aiAgentIndex] = endPoint;
i = lastOrigins.Count;
present = true;
}
}
//if not then generate the path
if (!present)
{
GeneratePath(aiAgentIndex, startPoint, endPoint, topLevelNode);
if (lastPaths[aiAgentIndex] == null || lastPaths[aiAgentIndex].Count < 1)
{
return(null);
}
lastDestinations[aiAgentIndex] = endPoint;
lastOrigins[aiAgentIndex] = startPoint;
}
}
//if the next level is the deepest level then return this level's path
if (startPoint.GetMaxDepth() == nextDepth)
{
return(lastPaths[aiAgentIndex]);
}
//If there is only one node in the path then something is wrong, because by this point the start and endpoint should be in different nodes
if (lastPaths[aiAgentIndex].Count < 2)
{
return(null);
}
int localStart = lastPaths[aiAgentIndex][0].GetIndexAtDepth(nextDepth);
NodeIndex localDest = lastPaths[aiAgentIndex][1];
//find the path within the first node of the current level path and return that
//Once the path has been found, pathfind within it's first node to determine how to get to the second node of the path
return(internalNodes[localStart].GetPath(aiAgentIndex, startPoint, localDest, topLevelNode));
}