protected function Bar($value, &$bar)
{
$x0 = $this->pad_left + $this->x0;
$l1 = $this->ClampHorizontal($x0);
$l2 = $this->ClampHorizontal($x0 + $value * $this->bar_unit_width);
$bar['x'] = min($l1, $l2);
$bar['width'] = abs($l1 - $l2);
}