private Node GetNode(int x, int y, int z)
{
Node n = null;
lock (gridBase)
{
n = gridBase.GetNode(x, y, z);
}
return(n);
}
private Node GetNode(int x, int y, int z)
{
Node n = null;
//When there are multiple threads, there can be conflicts, this helps prevent that from happening.
lock (gridBase)
{
n = gridBase.GetNode(x, y, z);
}
return(n);
}
private Node GetNode(int x, int y, int z)
{
Node n = null;
// this ensures that one thread is executing a piece of code at one time.
// keep in mind,
// one thread does not enter a critical section of code while another thread is in that critical section.
lock (gridBase)
{
n = gridBase.GetNode(x, y, z);
}
return(n);
}
private Node GetNeighborNode(Node adjPos, bool searchTopDown, Node currentNodePos)
{
//This is the meat. We can add all of the checks we need to tweak the alg.
//First, the usual A* stuff.
Node retVal = null;
//Let's take the node from the adjacent positions we passed
Node node = GetNode(adjPos.x, adjPos.y, adjPos.z);
//if it's not null and we can walk on it...
if (node != null && node.isWalkable)
{
//We can use this node.
retVal = node;
}//Otherwise...
else if (searchTopDown) //and we want 3d A*
{
//Then look at what the node has under it
adjPos.y -= 1;
Node bottomBlock = gridBase.GetNode(adjPos.x, adjPos.y, adjPos.z);
//If there is a bottom block and we can walk on it
if (bottomBlock != null && bottomBlock.isWalkable)
{
//We can return that.
retVal = bottomBlock;
}
else
{
//Otherwise, let's look up instead.
adjPos.y += 2;
Node topBlock = gridBase.GetNode(adjPos.x, adjPos.y, adjPos.z);
//Same as above.
if (topBlock != null && topBlock.isWalkable)
{
retVal = topBlock;
}
}
}
//If the node is diagonal to the current node then we check it's neighbors.
//To move diagonally, we need all 4 nodes walkable.
int originalX = adjPos.x - currentNodePos.x;
int originalZ = adjPos.z - currentNodePos.z;
if (Mathf.Abs(originalX) == 1 && Mathf.Abs(originalZ) == 1)
{
//The first block is originalX, 0 and the second to check is 0, originalZ.
//Both need to be walkable.
Node neighbor1 = gridBase.GetNode(currentNodePos.x + originalX, currentNodePos.y, currentNodePos.z + originalZ);
if (neighbor1 == null || !neighbor1.isWalkable)
{
retVal = null;
}
Node neighbor2 = gridBase.GetNode(currentNodePos.x, currentNodePos.y, currentNodePos.z + originalZ);
if (neighbor2 == null || !neighbor2.isWalkable)
{
retVal = null;
}
}
//Here we can add additional checks.
if (retVal != null)
{
//EX. Do not approach any nodes from the left
/*if(node.x < currentNodePos.x)
* {
* node = null;
* }*/
}
return(retVal);
}
