mthh/.block

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

## README.md

      
    Raw
  

              README.md
            
          
    Hatano Asymmetrical Equal Area projection (rotated by 10.2°).

  
## hatano.js
var NITER = 20,
    EPS = 1e-7,
    ONETOL = 1.000001,
    CN = 2.67595,
    CS = 2.43763,
    RCN = 0.37369906014686373063,
    RCS = 0.41023453108141924738,
    FYCN = 1.75859,
    FYCS = 1.93052,
    RYCN = 0.56863737426006061674,
    RYCS = 0.51799515156538134803,
    FXC = 0.85,
    RXC = 1.17647058823529411764,
    M_HALFPI = Math.PI / 2,
    sin = Math.sin,
    asin = Math.asin,
    abs = Math.abs,
    cos = Math.cos;

function hatanoRaw(lambda, phi) {
  var th1, c, i;
  c = sin(phi) * (phi < 0 ? CS : CN);
  for(i = NITER; i; --i){
      phi -= th1 = (phi + sin(phi) - c) / (1 + cos(phi));
      if(abs(th1) < EPS) break;
  }
  return [
    FXC * lambda * cos(phi *= 0.5),
    sin(phi) * (phi < 0 ? FYCS : FYCN)
  ];
}

hatanoRaw.invert = function(x, y) {
  var th = y * (y < 0 ? RYCS : RYCN);
  if(abs(th) > 1){
      if(abs(th) > ONETOL){
          // return;
          console.log('Error?');
      } else {
        th = th > 0 ? M_HALFPI : -M_HALFPI;
      }
  } else {
      th = asin(th);
  }
  x = RXC * x / cos(th);
  th += th;
  y = (th + sin(th)) * (y < 0 ? RCS : RCN);
  if(abs(y) > 1){
      if(abs(y) > ONETOL){
          console.log('Error?');
          // return;
      } else {
          y = y > 0 ? M_HALFPI : -M_HALFPI;
      }
  } else {
      y = asin(y);
  }
  return [x,  y];
};

## 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.v1.min.js"></script>
<script src="hatano.js"></script>
<script>
var svg = d3.select("svg"),
    width = +svg.attr("width"),
    height = +svg.attr("height"),
    g = svg.append("g");

var projection = d3.geoProjection(hatanoRaw)
    .scale(160)
    .rotate([-10.2, 0, 0])
    .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
            
          
## world-50m.json

      
Display the source blob

    
Display the rendered blob

    
    Raw
  

              world-50m.json
            
          
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	var NITER = 20,
	EPS = 1e-7,
	ONETOL = 1.000001,
	CN = 2.67595,
	CS = 2.43763,
	RCN = 0.37369906014686373063,
	RCS = 0.41023453108141924738,
	FYCN = 1.75859,
	FYCS = 1.93052,
	RYCN = 0.56863737426006061674,
	RYCS = 0.51799515156538134803,
	FXC = 0.85,
	RXC = 1.17647058823529411764,
	M_HALFPI = Math.PI / 2,
	sin = Math.sin,
	asin = Math.asin,
	abs = Math.abs,
	cos = Math.cos;

	function hatanoRaw(lambda, phi) {
	var th1, c, i;
	c = sin(phi) * (phi < 0 ? CS : CN);
	for(i = NITER; i; --i){
	phi -= th1 = (phi + sin(phi) - c) / (1 + cos(phi));
	if(abs(th1) < EPS) break;
	}
	return [
	FXC * lambda * cos(phi *= 0.5),
	sin(phi) * (phi < 0 ? FYCS : FYCN)
	];
	}

	hatanoRaw.invert = function(x, y) {
	var th = y * (y < 0 ? RYCS : RYCN);
	if(abs(th) > 1){
	if(abs(th) > ONETOL){
	// return;
	console.log('Error?');
	} else {
	th = th > 0 ? M_HALFPI : -M_HALFPI;
	}
	} else {
	th = asin(th);
	}
	x = RXC * x / cos(th);
	th += th;
	y = (th + sin(th)) * (y < 0 ? RCS : RCN);
	if(abs(y) > 1){
	if(abs(y) > ONETOL){
	console.log('Error?');
	// return;
	} else {
	y = y > 0 ? M_HALFPI : -M_HALFPI;
	}
	} else {
	y = asin(y);
	}
	return [x, y];
	};
	<!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.v1.min.js"></script>
	<script src="hatano.js"></script>
	<script>
	var svg = d3.select("svg"),
	width = +svg.attr("width"),
	height = +svg.attr("height"),
	g = svg.append("g");

	var projection = d3.geoProjection(hatanoRaw)
	.scale(160)
	.rotate([-10.2, 0, 0])
	.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>