Why Reykjavík? by fil

index.html

<!DOCTYPE html>
<meta charset="utf-8">
<body>
<script src="https://d3js.org/d3.v4.min.js"></script>
<script src="https://d3js.org/topojson.v2.min.js"></script>
<script>

var width = 960,
    height = 600;

var radius = height / 2 - 5,
    scale = radius,
    velocity = .02;

var projection = d3.geoOrthographic()
    .translate([width / 2, height / 2])
    .scale(scale)
    .clipAngle(90);

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

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

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

var zoom = d3
    .zoom()
    .on("zoom start end", zoomed)
    .scaleExtent([0.7, 5])
    .translateExtent([[0,0], [width, height]]);
canvas.call(zoom);

var init_scale = projection.scale(),
  init_translate = projection.translate();
function zoomed() {
  var t = d3.event.transform;
  projection.scale(init_scale * t.k)
    .translate(t.apply(init_translate));
}

d3.json("https://gist.githubusercontent.com/mbostock/4090846/raw/d534aba169207548a8a3d670c9c2cc719ff05c47/world-110m.json", function(error, world) {
  if (error) throw error;

  var land = topojson.feature(world, world.objects.land);

  var plane = {
      "type": "Feature",
      "properties": {},
      "geometry": {
        "type": "LineString",
        "coordinates": [
          [
            -121.28906250000001,
            35.17380831799959
          ],
          [
            -18.984375,
            64.32087157990324
          ],
          [
            1.7578125,
            47.754097979680026
          ]
        ]
      }
    }
  
  d3.timer(function(elapsed) {
    context.clearRect(0, 0, width, height);

    projection.rotate([velocity * elapsed, -40]);
    context.beginPath();
    path(land);
    context.fill();

    context.beginPath();
    path(plane);
    context.strokeStyle = 'green';
    context.stroke();

    context.strokeStyle = 'black';
    context.beginPath();
    path({type:"Sphere"});
    context.lineWidth = 2.5;
    context.stroke();
  });
});

d3.select(self.frameElement).style("height", height + "px");

</script>