/**
* A* implementation over Tile graph
*
* @param start : coordinates of start
* @param fin : coordinates of end
* @return LinkedList<Tile> representing path
*/
private static LinkedList<? extends Node> getPath(
Node[][] board, Vec2i start, Vec2i fin, Master m, Iterable<? extends Sprite> spriteSet) {
LinkedList<Node> path = new LinkedList<Node>();
PriorityQueue<Node> open = new PriorityQueue<Node>();
open.add(board[start.x][start.y]);
HashSet<Node> done = new HashSet<Node>();
if (board[fin.x][fin.y].impassible()) {
return null;
}
for (Sprite s : spriteSet) {
if (s.getPlayer() == m.whoseTurn() && s.getLocation().equals(new Vec2i(fin.y, fin.x))) {
return null;
}
}
board[start.x][start.y].setDistance(0);
while (!open.isEmpty()) {
Node curr = open.poll();
if (fin.x == curr.getCoords().x && fin.y == curr.getCoords().y) {
Node t = curr;
while (t.getPrev() != null) {
path.addFirst(t);
t = t.getPrev();
}
return path;
}
done.add(curr);
for (Node neigh : Pathfinding.passableNeighbors(board, curr, m, spriteSet)) {
if (done.contains(neigh)) {
continue;
}
if (neigh.getDistance() > curr.getDistance() + 1) {
neigh.setDistance(curr.getDistance() + 1);
neigh.setPrev(curr);
neigh.setEstimate(board[fin.x][fin.y]);
}
open.add(neigh);
}
}
return null;
}
