my $dir0='h:/active/tiger_data';
  my $sfips='42'; # pa 


# make $base->{$blockid10}{color} via 
# zipbyline reads a zip member sequentially 
#   as in http://search.cpan.org/~phred/Archive-Zip-1.59/lib/Archive/Zip.pm#Low-level_member_data_reading 
#  my $sn=$fips2state->{$sfips}.'2010.sf1'; 
#  my $zf=$dir0.'/sf1/'.$sn.'.zip';
#  my $mf=$fips2state->{$fips}.'geo2010.sf1'; ; 
#  my $member=zipbyline_start($zf,$mf); 
#  while (my $line=zipbyline_read($member)){ 
#    ... pull out datums AREALAND AREAWATR POP100, create density 
#    } # line   
#  zipbyline_close($member); 
# sort by density, total POP100, 
#   break into deciles, 
#   assign a decile color to each $base->{$blockid10}{color}

  my $dir=$dir0.'/shapes';
  my $state='tabblock2010_'.$sfips.'_pophu';
  my $shapefn=$dir.'/'.$state.'/'.$state;
  my $imgfn=$dir0.'/gifs/'.$state.'.gif'; 

  # this points to the unzipped dir now,
  # be nice to just point to $dir.'/'.$state.'.zip' instead 
  my $sf = Geo::ShapeFile->new ($shapefn); 
  $sf->caching(shp                => 0); 
  $sf->caching(dbf                => 0); 
  $sf->caching(shx                => 0); 
  $sf->caching(shapes_in_area     => 0); 

  my $x_min=$sf->x_min(); 
  my $x_max=$sf->x_max(); 
  my $y_max=90-$sf->y_min(); # need to invert 90 is top 0 is bot 
  my $y_min=90-$sf->y_max(); 
  my $totalblocks = $sf->shapes();
#   $totalblocks=5000; 


  my $xsize=$x_max-$x_min; 
  my $ysize=$y_max-$y_min; 

  my $imgy=5000; 
  my $yscale=$imgy/$ysize; 


  my $pfx=-0.00923452628555483*($sf->y_min)+ 1.15467278754118; # projection factor 


  my $imgx=$yscale*$xsize*$pfx;
  my $xscale=$imgx/($xsize); 

  sub xproj { return (($_[0])-($x_min))*$xscale; } 
  sub yproj { return ((90-$_[0])-$y_min)*$yscale; } 

  # create a new image
  my $im = new GD::Image($imgx+1,$imgy+1);

  for my $si (1 .. $totalblocks) {
    my %attr = $sf->get_dbf_record($si);
    my $blockid10 = $attr{BLOCKID10};
    my $color=$base->{$blockid10}{color}; 
    unless ($color) {$color=$yellow;}
    my $polygon = $sf->get_shp_record($si);
     for my $pi (1 .. $polygon->num_parts) {
        my $part = $polygon->get_part($pi);
        my $poly = new GD::Polygon;
        for my $hash (@$part){ 
          $poly->addPt(xproj($hash->{X}),yproj($hash->{Y}));
          } 
        my $first=$part->[0]; 
        my $last =$part->[-1]; 
        if ($first->{X} ne $last->{X} || $first->{Y} ne $last->{Y} ) { 
          $poly->addPt(xproj($first->{X}),yproj($first->{Y}));
          } 
        $im->filledPolygon($poly,$color);
        } # pi
    }  # si

  outlines (); 

  open (my $img,'>',$imgfn); binmode $img;print $img $im->gif;close $img;
  exit; 

sub outlines { 
  my $state='tl_2010_'.$sfips.'_county10';
  my $shapefn=$dir.'/'.$state.'/'.$state;
# this too points at an unzipped dir, 
# be nice to point at $dir.'/'.$state.'.zip' instead 
  my $sf = Geo::ShapeFile->new ($shapefn); 
  $sf->caching(shp                => 0); 
  $sf->caching(dbf                => 0); 
  $sf->caching(shx                => 0); 
  $sf->caching(shapes_in_area     => 0); 
  my $totalblocks = $sf->shapes();
  for my $si (1 .. $totalblocks) {
    my $polygon = $sf->get_shp_record($si);
    for my $pi (1 .. $polygon->num_parts) {
        my $part = $polygon->get_part($pi);
        my $poly = new GD::Polygon;
        for my $hash (@$part){ 
          $poly->addPt(xproj($hash->{X}),yproj($hash->{Y}));
          } 
        my $first=$part->[0]; 
        my $last =$part->[-1]; 
        if ($first->{X} ne $last->{X} || $first->{Y} ne $last->{Y} ) { 
          $poly->addPt(xproj($first->{X}),yproj($first->{Y}));
          } 
        $im->openPolygon($poly,$black);
        } # pi
    }  # si 

  }