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I'm trying to convert official boundaries of administrative regions of Poland from official governmental site (codgik.gov.pl). I want to use those data because they are official ones, and set contains additional levels of borders of that I cannot find in other data sets (such as Natural Earth).

I use approach similar to How to create a GeoJSON that works with D3?. However when I'm trying to use conversion ogr2ogr and plot the results using d3.js I fail. Data seems to be incorrectly translated giving essentially gibberish.

The same approach worked just fine w Natural Earth shapefiles.

By playing around with SVG (deleting paths) I can see that path overlaps and hugely and result in just black square.

Java GeoTools [quickstart tutorial] shows this shapefile without any problem, so I'm guessing mine conversions are off.

Shapefile set is available here (5.5MB)

JavaScript code:

d3.json("wojeowdztwa.json", function(error, map) {
  if (error) return console.error(error);

var projection = d3.geo.mercator()
//    .center([171677, 133223])
//    .scale(69)
    .translate([width / 2, height / 2]);

  var path = d3.geo.path()
    .projection(projection);

svg.append("g").attr("id", "polska")
    .selectAll("path")
      .data(map.features)
      .enter()
        .append("path")
        .attr("id", function(d) { return d.id; })
          .attr("d", path)
          .attr("class", "wojewodztwo");

Content of .PRJ file:

PROJCS["ETRS89 / Poland CS92", 
  GEOGCS["ETRS89", 
    DATUM["European Terrestrial Reference System 1989", 
      SPHEROID["GRS 1980", 6378137.0, 298.257222101], 
      TOWGS84[0,0,0]
    ], 
    PRIMEM["Greenwich", 0.0], 
    UNIT["Decimal Degree", 0.017453292519943295]
  ], 
  PROJECTION["Transverse_Mercator"], 
  PARAMETER["latitude_of_origin", 0.0], 
  PARAMETER["central_meridian", 18.999999999999982], 
  PARAMETER["scale_factor", 0.9993], 
  PARAMETER["false_easting", 500000.0], 
  PARAMETER["false_northing", -5300000.0], 
  UNIT["Meter", 1.0], 
  AUTHORITY["EPSG", 2180]
]

I'm very new to cartography.

  • 2
    Did you use ogr2ogr as ogr2ogr -f GeoJSON -s_srs epsg:2180 -t_srs epsg:4326 output.json input.shp ? – user30184 Aug 18 '15 at 4:54
  • Welcome to GIS SE! As a new user be sure to take the Tour – TsvGis Aug 18 '15 at 5:36
  • Thank you this finally did the trick, I've tried different combination of source and target srs but not this one. – czyzu Aug 19 '15 at 17:57
1

As @user30184 suggests, convert your shapefile to json and at the same time reproject it to WGS84 with:

ogr2ogr -f GeoJSON -s_srs epsg:2180 -t_srs epsg:4326 wojeowdztwa.json wojewodztwa.shp 

Then, define the projection in your script like this:

var projection = d3.geo.mercator()
    .center([21, 52])
    .scale(2000)
    .translate([width / 2, height / 2]);

You then should see this:

enter image description here

Complete script:

var width = 600,
    height = 600;

var svg = d3.select("body").append("svg")
    .attr("width", width)
    .attr("height", height);

d3.json("wojeowdztwa.json", function(error, map) {
  if (error) return console.error(error);

var projection = d3.geo.mercator()
    .center([21, 52])
    .scale(2000)
    .translate([width / 2, height / 2]);

var path = d3.geo.path()
    .projection(projection);

svg.append("g").attr("id", "polska")
    .selectAll("path")
      .data(map.features)
      .enter()
        .append("path")
        .attr("id", function(d) { return d.id; })
        .attr("d", path)
        .attr("class", "wojewodztwo");
});

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