D3 Examples - Identity projection of map in d3.js

xxxxxxxxxx
 
<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8" />
​
    <script src="https://d3js.org/d3.v3.min.js"></script>
  </head>
  <body>
    <div id="vis">
    </div>
​
    <script>
      var height = 400;
      var width  = 400;
​
      var vis = d3.select("#vis").append("svg")
          .attr("width", width).attr("height", height)
​
      d3.json("po_2012_simplified.json", function(json) {
​
          var projection = d3.geo.projection(function(x, y) { return [x, y];})
            .precision(0).scale(1).translate([0, 0]);
​
          var path = d3.geo.path().projection(projection);
​
          var bounds = path.bounds(json),
              scale  = .95 / Math.max((bounds[1][0] - bounds[0][0]) / width, 
                      (bounds[1][1] - bounds[0][1]) / height),
              transl = [(width - scale * (bounds[1][0] + bounds[0][0])) / 2, 
                      (height - scale * (bounds[1][1] + bounds[0][1])) / 2];
​
          projection.scale(scale).translate(transl);
​
          vis.selectAll("path").data(json.features).enter().append("path")
            .attr("d", path)
            .style("fill", "#D0D0D0")
            .style("stroke-width", "0.5px")
            .style("stroke", "black")
        });
​
    </script>
  </body>
</html>
​
    