I would like to inform developers about a problem I encountered when trying to use imagefilledrectangle.

I noted that the order in which the start and end y coordinates are listed is extremely important.
as in the statements below.
if($this->d_values[$i]['unit_value'] < 0)
imagefilledrectangle($this->img,$position_x, $start_y , $end_x, $end_y ,$d_color);            
else                
imagefilledrectangle($this->img, $position_x,$ end_y , $end_x, $start_y,$d_colour);            
            

Thanks