ryaninvents/.block

## .block
license: gpl-3.0

## readme-blue-marble.jpg

      
    Raw
  

              readme-blue-marble.jpg
            
          
## README.md

      
    Raw
  

              README.md
            
          
    The NASA Blue Marble is reprojected using a Florida-centric azimuthal projection. Based on View of the World from 9th Avenue

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

body {
  background: #222;
}

</style>
<body>
<script src="//d3js.org/d3.v3.min.js"></script>
<script src="//d3js.org/d3.geo.projection.v0.min.js"></script>
<script>


function azimuthalRaw(scale) {
  return function(x, y) {
    var cx = Math.cos(x),
        cy = Math.cos(y),
        k = scale(cx * cy);
    return [
      k * cy * Math.sin(x),
      k * Math.sin(y)
    ];
  }
}

function azimuthalInvert(angle) {
  return function(x, y) {
    var z = Math.sqrt(x * x + y * y),
        c = angle(z),
        sc = Math.sin(c),
        cc = Math.cos(c);
    return [
      Math.atan2(x * sc, z * cc),
      Math.asin(z && y * sc / z)
    ];
  }
}

const POWER = 3;
const POSITION = [30.4300065,-84.2842401];

var azimuthalExpmtlRaw = azimuthalRaw(function(z) {
  const c = Math.acos(z);
  if (!c) return c;
  return Math.pow(c, 1 / POWER) / Math.sin(c);
});

azimuthalExpmtlRaw.invert = azimuthalInvert(function(z) {
  return Math.pow(z, POWER);
});

function azimuthalExperimental() {
  return d3.geo.projection(azimuthalExpmtlRaw)
      .scale(124.75)
      .clipAngle(180 - 1e-3);
}


var width = 960,
    height = 960;

var projection = azimuthalExperimental()
    .scale(350)
    .translate([width / 2, height / 2])
    .rotate([-POSITION[1], -POSITION[0]]);

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

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

var context = canvas.node().getContext("2d");

var image = new Image;
image.onload = onload;
image.src = "readme-blue-marble.jpg";

function onload() {
  var dx = image.width,
      dy = image.height;

  canvas.attr('width', dx).attr('height', dy);

  context.drawImage(image, 0, 0, dx, dy);

  var sourceData = context.getImageData(0, 0, dx, dy).data,
      target = context.createImageData(width, height),
      targetData = target.data;

  for (var y = 0, i = -1; y < height; ++y) {
    for (var x = 0; x < width; ++x) {
      var p = projection.invert([x, y]), λ = p[0], φ = p[1];
      if (λ > 180 || λ < -180 || φ > 90 || φ < -90) { i += 4; continue; }
      var q = ((90 - φ) / 180 * dy | 0) * dx + ((180 + λ) / 360 * dx | 0) << 2;
      targetData[++i] = sourceData[q];
      targetData[++i] = sourceData[++q];
      targetData[++i] = sourceData[++q];
      targetData[++i] = 255;
    }
  }

  canvas
    .attr("width", width)
    .attr("height", height);
  context.clearRect(0, 0, width, height);
  context.putImageData(target, 0, 0);
}

</script>

## thumbnail.png

      
    Raw
  

              thumbnail.png
	<!DOCTYPE html>
	<meta charset="utf-8">
	<style>

	body {
	background: #222;
	}

	</style>
	<body>
	<script src="//d3js.org/d3.v3.min.js"></script>
	<script src="//d3js.org/d3.geo.projection.v0.min.js"></script>
	<script>


	function azimuthalRaw(scale) {
	return function(x, y) {
	var cx = Math.cos(x),
	cy = Math.cos(y),
	k = scale(cx * cy);
	return [
	k * cy * Math.sin(x),
	k * Math.sin(y)
	];
	}
	}

	function azimuthalInvert(angle) {
	return function(x, y) {
	var z = Math.sqrt(x * x + y * y),
	c = angle(z),
	sc = Math.sin(c),
	cc = Math.cos(c);
	return [
	Math.atan2(x * sc, z * cc),
	Math.asin(z && y * sc / z)
	];
	}
	}

	const POWER = 3;
	const POSITION = [30.4300065,-84.2842401];

	var azimuthalExpmtlRaw = azimuthalRaw(function(z) {
	const c = Math.acos(z);
	if (!c) return c;
	return Math.pow(c, 1 / POWER) / Math.sin(c);
	});

	azimuthalExpmtlRaw.invert = azimuthalInvert(function(z) {
	return Math.pow(z, POWER);
	});

	function azimuthalExperimental() {
	return d3.geo.projection(azimuthalExpmtlRaw)
	.scale(124.75)
	.clipAngle(180 - 1e-3);
	}


	var width = 960,
	height = 960;

	var projection = azimuthalExperimental()
	.scale(350)
	.translate([width / 2, height / 2])
	.rotate([-POSITION[1], -POSITION[0]]);

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

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

	var context = canvas.node().getContext("2d");

	var image = new Image;
	image.onload = onload;
	image.src = "readme-blue-marble.jpg";

	function onload() {
	var dx = image.width,
	dy = image.height;

	canvas.attr('width', dx).attr('height', dy);

	context.drawImage(image, 0, 0, dx, dy);

	var sourceData = context.getImageData(0, 0, dx, dy).data,
	target = context.createImageData(width, height),
	targetData = target.data;

	for (var y = 0, i = -1; y < height; ++y) {
	for (var x = 0; x < width; ++x) {
	var p = projection.invert([x, y]), λ = p[0], φ = p[1];
	if (λ > 180 \|\| λ < -180 \|\| φ > 90 \|\| φ < -90) { i += 4; continue; }
	var q = ((90 - φ) / 180 * dy \| 0) * dx + ((180 + λ) / 360 * dx \| 0) << 2;
	targetData[++i] = sourceData[q];
	targetData[++i] = sourceData[++q];
	targetData[++i] = sourceData[++q];
	targetData[++i] = 255;
	}
	}

	canvas
	.attr("width", width)
	.attr("height", height);
	context.clearRect(0, 0, width, height);
	context.putImageData(target, 0, 0);
	}

	</script>