private void InitializeSearchNodes(Map map)
{
searchNodes = new SearchNode[levelWidth, levelHeight];
for (int x = 0; x < levelWidth; ++x)
{
for (int y = 0; y < levelHeight; ++y)
{
SearchNode node = new SearchNode();
node.Position = new Point(x, y);
node.Walkable = map.map[x, y].walkable;
if (node.Walkable)
{
node.Neighbors = new SearchNode[8];
searchNodes[x, y] = node;
}
}
}
for (int x = 0; x < levelWidth; x++)
{
for (int y = 0; y < levelHeight; y++)
{
SearchNode node = searchNodes[x, y];
if (node == null || node.Walkable == false)
{
continue;
}
Point[] neighbors = new Point[]
{
new Point (x, y - 1),
new Point (x, y + 1),
new Point (x - 1, y),
new Point (x + 1, y)
};
for (int i = 0; i < neighbors.Length; i++)
{
Point position = neighbors[i];
if (position.X < 0 || position.X > levelWidth - 1 || position.Y < 0 || position.Y > levelHeight - 1)
continue;
SearchNode neighbor = searchNodes[position.X, position.Y];
if (neighbor == null || neighbor.Walkable == false)
continue;
node.Neighbors[i] = neighbor;
}
}
}
}
/// <summary>
/// Use the parent field of the search nodes to trace
/// a path from the end node to the start node.
/// </summary>
private List<Vector2> FindFinalPath(SearchNode startNode, SearchNode endNode)
{
closedList.Add(endNode);
SearchNode parentTile = endNode.Parent;
// Trace back through the nodes using the parent fields
// to find the best path.
while (parentTile != startNode)
{
closedList.Add(parentTile);
parentTile = parentTile.Parent;
}
List<Vector2> finalPath = new List<Vector2>();
// Reverse the path and transform into world space.
for (int i = closedList.Count - 1; i >= 0; i--)
{
finalPath.Add(new Vector2(closedList[i].Position.X * 48.0f + Map.X_OFFSET, closedList[i].Position.Y * 48.0f + Map.Y_OFFSET));
}
return finalPath;
}
