Graph::DrawGraph PHP Method

    public function DrawGraph()
    {
        $canvas_id = $this->NewID();
        $contents = $this->Canvas($canvas_id);
        $contents .= $this->DrawTitle();
        $contents .= $this->Draw();
        $contents .= $this->DrawLegend();
        // rounded rects need a clip path
        if ($this->back_round) {
            $group = array('clip-path' => "url(#{$canvas_id})");
            $body = $this->Element('g', $group, NULL, $contents);
        } else {
            $body = $contents;
        }
        return $body;
    }