mthh/.block

## .block
license: gpl-3.0
border: no

## README.md

      
    Raw
  

              README.md
            
          
    Winkel 1

The Winkel I projection, with a "latitude of truescale" defined at 45°.

  
## index.html
<!DOCTYPE html>
<meta charset="utf-8">
<style>

.graticule {
  fill: none;
  stroke: #777;
  stroke-width: 0.5px;
  stroke-opacity: 0.5;
}

.land {
  fill: #222;
}

.boundary {
  fill: none;
  stroke: #fff;
  stroke-width: 0.5px;
}

</style>
<svg width="960" height="500"></svg>
<script src="//d3js.org/d3.v4.min.js"></script>
<script src="//d3js.org/topojson.v2.min.js"></script>
<script src="winkel1.js"></script>
<script>
var svg = d3.select("svg"),
    width = +svg.attr("width"),
    height = +svg.attr("height"),
    g = svg.append("g");

var projection = d3.geoProjection(winkel1Raw(45))
    .scale(140)
    .translate([width / 2, height / 2])
    .precision(0.1);

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

var graticule = d3.geoGraticule();

g.append("path")
    .datum(graticule)
    .attr("class", "graticule")
    .attr("d", path);

g.append("path")
    .datum({type: "Sphere"})
    .attr("class", "sphere")
    .attr("d", path)
    .attr("fill", "none")
    .attr("stroke", "black");

d3.json("world-50m.json", function(error, world) {
  if (error) throw error;

  g.insert("path", ".graticule")
      .datum(topojson.feature(world, world.objects.land))
      .attr("class", "land")
      .attr("d", path);

  g.insert("path", ".graticule")
      .datum(topojson.mesh(world, world.objects.countries, function(a, b) { return a !== b; }))
      .attr("class", "boundary")
      .attr("d", path);
});
</script>

## thumbnail.png

      
    Raw
  

              thumbnail.png
            
          
## winkel1.js
var cos = Math.cos;

function winkel1Raw(lat_truescale) {
  var cosphi1 = lat_truescale ? cos(lat_truescale) : 0;

  function forward(lambda, phi) {
    var x = lambda, y = phi;
    return [0.5 * x * (cosphi1 + cos(phi)), y];
  }

  forward.invert = function(x, y) {
    var lambda = x, phi = y;
    return [2 * lambda / (cosphi1 + cos(phi)), phi];
  };

  return forward;
}

## world-50m.json

      
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              world-50m.json
            
          
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	<!DOCTYPE html>
	<meta charset="utf-8">
	<style>

	.graticule {
	fill: none;
	stroke: #777;
	stroke-width: 0.5px;
	stroke-opacity: 0.5;
	}

	.land {
	fill: #222;
	}

	.boundary {
	fill: none;
	stroke: #fff;
	stroke-width: 0.5px;
	}

	</style>
	<svg width="960" height="500"></svg>
	<script src="//d3js.org/d3.v4.min.js"></script>
	<script src="//d3js.org/topojson.v2.min.js"></script>
	<script src="winkel1.js"></script>
	<script>
	var svg = d3.select("svg"),
	width = +svg.attr("width"),
	height = +svg.attr("height"),
	g = svg.append("g");

	var projection = d3.geoProjection(winkel1Raw(45))
	.scale(140)
	.translate([width / 2, height / 2])
	.precision(0.1);

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

	var graticule = d3.geoGraticule();

	g.append("path")
	.datum(graticule)
	.attr("class", "graticule")
	.attr("d", path);

	g.append("path")
	.datum({type: "Sphere"})
	.attr("class", "sphere")
	.attr("d", path)
	.attr("fill", "none")
	.attr("stroke", "black");

	d3.json("world-50m.json", function(error, world) {
	if (error) throw error;

	g.insert("path", ".graticule")
	.datum(topojson.feature(world, world.objects.land))
	.attr("class", "land")
	.attr("d", path);

	g.insert("path", ".graticule")
	.datum(topojson.mesh(world, world.objects.countries, function(a, b) { return a !== b; }))
	.attr("class", "boundary")
	.attr("d", path);
	});
	</script>
	var cos = Math.cos;

	function winkel1Raw(lat_truescale) {
	var cosphi1 = lat_truescale ? cos(lat_truescale) : 0;

	function forward(lambda, phi) {
	var x = lambda, y = phi;
	return [0.5 * x * (cosphi1 + cos(phi)), y];
	}

	forward.invert = function(x, y) {
	var lambda = x, phi = y;
	return [2 * lambda / (cosphi1 + cos(phi)), phi];
	};

	return forward;
	}