private boolean isSafeToDrag(GraphNode node, double posX, double posY) {
		if(posX - node.RADIUS < 0 || posX + node.RADIUS > getWidth())
			return false;
		if(posY - node.RADIUS < 0 || posY + node.RADIUS > getHeight())
			return false;

		if(graph.size() == 1) // if there's only one node it is safe to drag
			return true;

		for(GraphNode cursor : graph.getNodes()) {
			if(cursor != node) // not to compare with the same node to drag
				if(computeRealDistance(cursor, posX, posY) < 12.5)
					return false;
		}
		return true;
	}