insdraw_size=$size,$size
pic_range=$[max($xmax-($xmin),$ymax-($ymin))/2]
draw_range=$[2.4*$pic_range/$zoomfactor]
midx=$[($xmin+($xmax))/2]
midy=$[($ymin+($ymax))/2]
shiftrange=$[$draw_range*0.4]
!if $zoomfactor<=1
 !distribute item $midx,$midy into xshift,yshift
!else
 xshift=$[max(min($xshift,$midx+$pic_range),$midx-$pic_range)]
 yshift=$[max(min($yshift,$midy$pic_range),$midy-$pic_range)]
 !if NaN isin $xshift
  xshift=$midx
 !endif
 !if NaN isin $yshift
  yshift=$midy
 !endif
!endif

stx=$[$xshift-$draw_range/2]
sty=$[$yshift-$draw_range/2]
prop=$[$size/$draw_range]
draw_src=fill 1,1,$color0

