Rotating Orthographic by mbostock

index.html

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

path {
  fill: none;
  stroke-linejoin: round;
}

.sphere,
.graticule {
  stroke: #aaa;
}

.equator {
  stroke: red;
  stroke-width: 2px;
}

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

var width = 960,
    height = 500,
    rotate = [10, -10],
    velocity = [.003, -.001],
    time = Date.now();

var projection = d3.geo.orthographic()
    .scale(240)
    .translate([width / 2, height / 2])
    .clipAngle(90 + 1e-6)
    .precision(.3);

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

var graticule = d3.geo.graticule();

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

svg.append("path")
    .datum({type: "Sphere"})
    .attr("class", "sphere")
    .attr("d", path);

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

svg.append("path")
    .datum({type: "LineString", coordinates: [[-180, 0], [-90, 0], [0, 0], [90, 0], [180, 0]]})
    .attr("class", "equator")
    .attr("d", path);

var feature = svg.selectAll("path");

d3.timer(function() {
  var dt = Date.now() - time;
  projection.rotate([rotate[0] + velocity[0] * dt, rotate[1] + velocity[1] * dt]);
  feature.attr("d", path);
});

</script>