public void highlightVisibleFrames(Agent agent) {
    	for (int x = -agent.getFieldOfView(); x <= agent.getFieldOfView(); x++ ) {
    		for (int y = -agent.getFieldOfView(); y <= agent.getFieldOfView(); y++) {
    			int yAfter = agent.getMapFrame().getY() + y;
    			int xAfter = agent.getMapFrame().getX() + x;
    			if (yAfter < this.backgroundTileGrid.size() && yAfter >= 0 
    					&& xAfter < this.backgroundTileGrid.get(0).size() && xAfter >=0) {
    				this.backgroundTileGrid.get(yAfter).get(xAfter).setBorder(new LineBorder(new Color(185, 226, 18), 3, true));
    			}
    		}
    	}
    }