Inheritance: extends ThreeDGraph
 /**
  * Overridden to prevent drawing behind higher bars
  * $offset_y should be true for inner bars
  */
 protected function BarLabel($value, &$bar, $offset_y = null)
 {
     $font_size = $this->bar_label_font_size;
     $space = $this->bar_label_space;
     if ($offset_y) {
         // bar too small, would be above
         if ($bar['height'] < $font_size + 2 * $space) {
             return parent::BarLabel($value, $bar, ($bar['height'] + $font_size) / 2);
         }
         // option set to above
         if ($this->bar_label_position == 'above') {
             $this->bar_label_position = 'top';
             $label = parent::BarLabel($value, $bar);
             $this->bar_label_position = 'above';
             return $label;
         }
     }
     return parent::BarLabel($value, $bar);
 }
 /**
  * Override AdjustAxes to change depth
  */
 protected function AdjustAxes(&$x_len, &$y_len)
 {
     /**
      * The depth is roughly 1/$num - but it must also take into account the
      * bar and group spacing, which is where things get messy
      */
     $ends = $this->GetAxisEnds();
     $num = $ends['k_max'][0] - $ends['k_min'][0] + 1;
     $block = $x_len / $num;
     $group = count($this->values);
     $a = $this->bar_space;
     $b = $this->group_space;
     $c = ($block - $a - ($group - 1) * $b) / $group;
     $d = ($a + $c) / $block;
     $this->depth = $d;
     return parent::AdjustAxes($x_len, $y_len);
 }
 /**
  * construct multigraph
  */
 public function Values($values)
 {
     parent::Values($values);
     if (!$this->values->error) {
         $this->multi_graph = new MultiGraph($this->values, $this->force_assoc, $this->datetime_keys, $this->require_integer_keys);
     }
 }