dump.pl

The boundary.tar.gz file referenced below is a test file to run the example. It has not been uploaded to wiki, because I can't do that. -sw ​http://www.highwayengineer.co.medina.oh.us/boundary.tar.gz

#!/usr/bin/perl -w
#
# Given a shapefile name this routine will dump out the shapefile type,
#   members, & applicable coordinate information.
#
# Required modules are mapscript (installed as part of make install)
#    & Getopt (normally included with Perl).
#   Please download boundary.tar.gz also, and:
#     tar -xf boundary.tar.gz --ungzip
#
# Suggested run method = ./dump.pl -file=boundary > /tmp/boundary.dump
use mapscript;
use Getopt::Long;
#
# Declare a hash for easy access to the shape types.
%types = ( '1' => 'point',
           '3' => 'arc',
           '5' => 'polygon',
           '8' => 'multipoint'
         );
#
# Declare an initial value for the shapefile extents.
my $shapeminx = 0,
my $shapeminy = 0;
my $shapemaxx = 1;
my $shapemaxy = 1;
#
# Check input for a specified file name.
&GetOptions("file=s", \$file);
if(!$file) {
  print "Syntax: dump.pl -file=[filename]\n";
  exit 0;
}
#
# Open the specified shapefile.
$shapefile = new shapefileObj($file, -1) or die "Unable to open shapefile $file";
#
# Print shapefile type & number of shapes.
print "Shapefile opened (type=". $types{$shapefile->{type}} .") with ".
$shapefile->{numshapes} ." shape(s)\n";
#
# Open a shape object for pulling the shapefile shapes into.
$shape = new shapeObj(-1);
#
# Loop through each shape in the shapefile.
for($i=0; $i<$shapefile->{numshapes}; $i++) {
    #
    # Pull the nth shape into the shape object for analysis.
    $shapefile->get($i, $shape);
    #
    # Print the shapes number of lines.
    print "Shape $i has ". $shape->{numlines} ." part(s) - ";
    #
    # Get the bounds.
    my $minx = $shape->{bounds}->{minx};
    my $miny = $shape->{bounds}->{miny};
    my $maxx = $shape->{bounds}->{maxx};
    my $maxy = $shape->{bounds}->{maxy};    
    #
    # Print the bounds for the shape.
    printf "bounds (%f,%f) (%f,%f)\n", $minx, $miny, $maxx, $maxy;
    #
    # Is this the first shape.
    if ( $i == 0 ) {
      #
      # Set the initial bounds to an actual shape.
      $shapeminx = $minx;
      $shapeminy = $miny;
      $shapemaxx = $maxx;
      $shapemaxy = $maxy;
    }
     else {
      #
      # Create compounded shapefile extent.
      #   Note: This is just an example, there is a better way to do this.
      #         See shpinfo.pl .
      if ($minx < $shapeminx) {
        $shapeminx = $minx;
      }
      if ($miny < $shapeminy) {
        $shapeminy = $miny;
      }
      if ($maxx > $shapemaxx) {
        $shapemaxx = $maxx;
      }
      if ($maxy > $shapemaxy) {
        $shapemaxy = $maxy;
      }
     }
    #
    # Loop through each line in the shape.
    for($j=0; $j<$shape->{numlines}; $j++) {
        #
        # Create the line object.
        $part = $shape->get($j);
        #
        # Print the number of points in the line.
        print "Part $j has ". $part->{numpoints} ." point(s)\n";
        #
        # Loop through each point.
        for($k=0; $k<$part->{numpoints}; $k++) {
            #
            # Create the point object.
            $point = $part->get($k);
            #
            # Print the x & y coordinate for the point.
            print "$k: ". $point->{x} .", ". $point->{y} ."\n";
        }
    }
}
#
# Print the shapefiles bounding rectangle.
print "$file\'s Bounding Rectangle is $shapeminx, $shapeminy, $shapemaxx, $shapemaxy\n";

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