
color_grid=220,220,220
step=$[$size/(2*$grid)]

grid_src=
!for i=-$grid to $grid
 !if $i!=0
  grid_src=$grid_src\
	line $border,$[$size/2+$border-($i*$step)],$[$border+$size],$[$size/2+$border-($i*$step)],$color_grid\
	line $[$size/2+$border-($i*$step)],$border,$[$size/2+$border-($i*$step)],$[$border+$size],$color_grid
 !endif
!next i

