public void checkBorderCollision(){
		for(Character c : characters){
			if(c.getX() > 800-c.getWidth() || c.getX() < 0+c.getWidth()){
				moveBack(c);
			}
			if(c.getY() > 640-c.getHeight() || c.getY() < 0+c.getHeight() ){
				moveBack(c);
			}
		}
	}