private void calculateDoorPaths() {
		doorPaths = new Path[doorGraph.length][doorGraph.length];
		for (int i = 0; i < doorPaths.length; i++) {
			for (int j = 0; j < i; j++) {
				if (i == j || doorGraph[i][j] <= 0) {
					// Doors are equal or not adjacent
					doorPaths[i][j] = null;
					continue;
				}
				Door from = WorldFactory.findDoorForIdentifier(i);
				Door to = WorldFactory.findDoorForIdentifier(j);
				if (from != null && to != null) {
					doorPaths[i][j] = PathFactory.findPath(from, to);
				} else {
					doorPaths[i][j] = null;
				}
			}
		}
	}