private void keyActions() {
        if (keys.size()>0) {
            for (int i=0; i <= keys.size()-1; i++) {
                int k = keys.get(i);
                if (k == KeyEvent.VK_UP) {
                    cam.moveForward();
                }
                if (k == KeyEvent.VK_DOWN) {
                    cam.moveBackward();
                }
                if (k == KeyEvent.VK_LEFT) {
                    cam.turnLeft();
                }
                if (k == KeyEvent.VK_RIGHT) {
                    cam.turnRight();
                }
            }
        }
    }