WWSD #6: d3.js projections

Working with spatial data

Example #6

Working with d3.js projections for mapping geospatial data

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forked from enjalot's block: WWSD #6: d3.js projections

<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.5.5/d3.min.js"></script>
  <style>
    body { margin:0;position:fixed;top:0;right:0;bottom:0;left:0; }
    svg { 
      width:100%; 
      height: 100%;
    }
    .graticule {
      fill: none;
      stroke: #777;
      stroke-width: .5px;
      stroke-opacity: .5;
		}
    
    .fill {
      fill: red;
    }
  </style>
</head>

<body>
  <script src="//d3js.org/d3.geo.projection.v0.min.js"></script>
  <script>
    var width = 960;
    var height = 500;
    
    var svg = d3.select("body").append("svg")
    
    var projection = d3.geo.mercator()
      .scale(width / 2 / Math.PI)
      .scale(100)
      .translate([width / 2, height / 2]);
    
		//https://gist.github.com/mbostock/a7ae83252305ed4d54d4
    var projectionWerner = d3.geo.bonne()
    .center([0, 27])
    .scale(120)
    .translate([width / 2, height / 2])
    .parallel(90)
    .precision(0.2);

var path = d3.geo.path()
      .projection(projectionWerner);
    
    var graticule = d3.geo.graticule();
    
    svg.append("defs").append("path")
    .datum({type: "Sphere"})
    .attr("id", "sphere")
    .attr("d", path);
    
    svg.append("use")
    .attr("class", "fill")
    .attr("xlink:href", "#sphere");
    
    svg.append("path")
    .datum(graticule)
    .attr("class", "graticule")
    .attr("d", path);
    
    var url = "https://enjalot.github.io/wwsd/data/world/world-110m.geojson";
    
    var sf = projectionWerner([-122.41, 37.77]);

d3.json(url, function(err, geojson) {
      svg.append("path")
        .attr("d", path(geojson))
      
      svg.append("circle")
      	.attr({
        	cx: sf[0],
        	cy: sf[1],
        	r: 5,
        	fill: "cornflowerblue"
      });
    })
    
  </script>
</body>

https://cdnjs.cloudflare.com/ajax/libs/d3/3.5.5/d3.min.js

https://d3js.org/d3.geo.projection.v0.min.js