public void paintPoints(Graphics2D g2d) { // this paints the points
        for(FunctionSubpanel sub : Client.equationPanel.functionList){
            g2d.setColor(sub.graphColor);
            for(int i = 0; i < sub.getPointsList().size(); i++){
                g2d.fillOval(sub.getPointsList().get(i).getX() + (int)(this.getPreferredSize().width/2) - this.pointSize/2,
                             -sub.getPointsList().get(i).getY() + (int)(this.getPreferredSize().height/2) - this.pointSize/2,
                             this.pointSize,
                             this.pointSize);
            }
        }
    }