D3 Examples - Orthographic Clipping

Orthographic Clipping

The above grid demonstrates an orthographic azimuthal projection. The lines are at uniform 10º increments of latitude and longitude.

Part 2 of 3.

To see this technique applied to real geographic features, see the Spinny Globe example.

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<!DOCTYPE html>
<meta charset="utf-8">
<style>
​
circle,
path {
  fill: none;
  stroke: #333;
}
​
circle {
  stroke-width: 2px;
}
​
</style>
<body>
<script src="//d3js.org/d3.v3.min.js"></script>
<script>
​
var width = 960,
    height = 500;
​
var rotate = [-71.03, 42.37],
    velocity = [.018, .006];
​
var projection = d3.geo.orthographic()
    .scale(height / 2.1)
    .translate([width / 2, height / 2])
    .clipAngle(90)
    .precision(.5);
  
var url = "https://enjalot.github.io/wwsd/data/world/world-110m.geojson";
  d3.json(url, function(err, geojson) {
    svg.append("path")
    .attr("d", path(geojson))
 
var point = projection([0, 52])
svg.append ("circle")
.attr({
  cx: point[0],
  cy: point[1],
  r:5,
  fill: "red"
  
})
 })
​
​
​
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);
​
var feature = svg.append("path")
    .datum(graticule);
​
svg.append("circle")
    .attr("cx", width / 2)
    .attr("cy", height / 2)
    .attr("r", 240);
​
d3.timer(function(elapsed) {
  projection.rotate([rotate[0] + elapsed * velocity[0], rotate[1] + elapsed * velocity[1]]);
  feature.attr("d", path);
});
​
</script>
​
    