Re: OSM Download als svg?

Inzwischen hab ich selber ein Script dafür geschrieben. Es gibt zwar noch viel zu verbessern, aber zumindest ist mal was da, worauf man aufbauen kann. Da kommt richtig die Lust, einen Renderer drauf aufzusetzen.

#!/usr/bin/perl
#␣(c)␣Friedrich␣Volkmann␣2012

use␣strict;
use␣LWP::Simple;
use␣Math::Trig␣':pi';

sub␣usage␣{
print␣"usage:␣$0:␣left␣right␣bottom␣top␣outfile\n";
exit␣1;
}

my␣$left␣=␣shift␣@ARGV;
usage()␣unless␣$left␣=~␣/^\d+(?:\.\d*)?$/;
my␣$right␣=␣shift␣@ARGV;
usage()␣unless␣$right␣=~␣/^\d+(?:\.\d*)?$/;
my␣$bottom␣=␣shift␣@ARGV;
usage()␣unless␣$bottom␣=~␣/^\d+(?:\.\d*)?$/;
my␣$top␣=␣shift␣@ARGV;
usage()␣unless␣$top␣=~␣/^\d+(?:\.\d*)?$/;
my␣$outfile␣=␣shift␣@ARGV;
usage()␣unless␣$outfile;

my␣$med_y␣=␣($top␣+␣$bottom)␣/␣2;
my␣$ratio␣=␣cos␣($med_y␣*␣pi␣/␣180);
my␣($tot_x,$tot_y);
if␣($right␣-␣$left␣>␣$top␣-␣$bottom)␣{
$tot_x␣=␣1000;
$tot_y␣=␣($top␣-␣$bottom)␣/␣($right␣-␣$left)␣*␣1000;
}␣else␣{
$tot_y␣=␣1000;
$tot_x␣=␣($right␣-␣$left)␣/␣($top␣-␣$bottom)␣*␣1000;
}
sub␣transform_x␣{
my␣$x␣=␣$_[0];
return␣($x␣-␣$left)␣*␣$ratio␣*␣$tot_x␣/␣($right␣-␣$left);
}

sub␣transform_y␣{
my␣$y␣=␣$_[0];
return␣($top␣-␣$y)␣*␣$tot_y␣/␣($top␣-␣$bottom);
}

my␣$osm␣=␣get("http://www.openstreetmap.org/api/0.6/map?bbox=$left,$bottom,$right,$top");
#print␣$osm;

exit␣unless␣$osm;
my␣@lines␣=␣split␣/\n/,␣$osm;
my␣%nodes;
my␣@ways;
for␣(@lines)␣{
if␣(/^\s*<node␣id="(\d+)"␣lat="(\d*(?:\.\d*)?)"␣lon="(\d*(?:\.\d*)?)"/)␣{
$nodes{$1}␣=␣{x␣=>␣$3,␣y␣=>␣$2};
}␣elsif␣(/^\s*<way␣/)␣{
push␣@ways,␣[];
}␣elsif␣(/^\s*<nd␣ref="(\d+)"/)␣{
push␣@{$ways[$#ways]},␣{x␣=>␣$nodes{$1}->{x},␣y␣=>␣$nodes{$1}->{y}};
$nodes{$1}->{in_a_way}␣=␣1;
}
}
open␣SVG,␣">$outfile"␣or␣die␣"could␣not␣open␣$outfile␣for␣writing";
print␣SVG␣"<?xml␣version='1.0'␣standalone='no'?>\n";
print␣SVG␣"<!DOCTYPE␣svg␣PUBLIC␣'-//W3C//DTD␣SVG␣1.1//EN'␣'http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd'>\n";
print␣SVG␣"<svg␣width='$tot_x'␣height='$tot_y'␣xmlns='http://www.w3.org/2000/svg'␣xmlns:xlink='http://www.w3.org/1999/xlink'>\n";
print␣SVG␣"␣␣<title>OSM␣export</title>\n";

for␣(@ways)␣{
print␣SVG␣'<polyline␣fill="none"␣stroke="blue"␣stroke-width=".5"␣points="';
print␣SVG␣transform_x($_->{x})␣.␣",␣"␣.␣transform_y($_->{y})␣.␣"␣"␣for␣@$_;
print␣SVG␣'"/>'␣.␣"\n";
}
for␣(values␣%nodes)␣{
next␣if␣$_->{in_a_way};
print␣SVG␣'<circle␣fill="red"␣cx="'␣.␣transform_x($_->{x})␣.␣'"␣cy="'␣.␣transform_y($_->{y})␣.␣'"␣r=".5"␣/>'␣.␣"\n";
}

print␣SVG␣"</svg>\n";
close␣SVG;