Skip to content

Instantly share code, notes, and snippets.

@mbostock
Last active February 9, 2016 02:04
Show Gist options
  • Save mbostock/5735623 to your computer and use it in GitHub Desktop.
Save mbostock/5735623 to your computer and use it in GitHub Desktop.
Resampling Comparison
license: gpl-3.0

A comparison of the Van der Grinten projection, with and without D3’s adaptive resampling. Note the polygonal artifacts in Antarctica that are fixed with resampling.

<!DOCTYPE html>
<meta charset="utf-8">
<style>
body {
background: #fcfcfa;
}
.stroke {
fill: none;
stroke: #000;
stroke-width: 3px;
}
.fill {
fill: #fff;
}
.graticule {
fill: none;
stroke: #777;
stroke-width: .5px;
stroke-opacity: .5;
}
.land {
fill: #222;
}
.boundary {
fill: none;
stroke: #fff;
stroke-width: .5px;
}
</style>
<body>
<script src="//d3js.org/d3.v3.min.js"></script>
<script src="//d3js.org/d3.geo.projection.v0.min.js"></script>
<script src="//d3js.org/topojson.v1.min.js"></script>
<script>
var width = 960,
height = 500;
var projection = d3.geo.vanDerGrinten()
.scale(72)
.translate([0, 0])
.precision(.1);
var position = d3.scale.ordinal()
.domain([0, .1])
.rangePoints([0, width], 1.02);
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 g = svg.selectAll("g")
.data(position.domain())
.enter().append("g")
.attr("transform", function(d) { return "translate(" + position(d) + "," + height / 2 + ")"; });
g.append("defs").append("path")
.datum({type: "Sphere"})
.attr("id", "sphere")
.attr("d", path);
g.append("use")
.attr("class", "stroke")
.attr("xlink:href", "#sphere");
g.append("use")
.attr("class", "fill")
.attr("xlink:href", "#sphere");
g.append("path")
.datum(graticule)
.attr("class", "graticule")
.attr("d", path);
d3.json("/mbostock/raw/4090846/world-110m.json", function(error, world) {
if (error) throw error;
g.insert("path", ".graticule")
.datum(topojson.feature(world, world.objects.land))
.attr("class", "land");
g.insert("path", ".graticule")
.datum(topojson.mesh(world, world.objects.countries, function(a, b) { return a !== b; }))
.attr("class", "boundary");
g.each(function(d) {
projection.precision(d);
d3.select(this).selectAll(".land,.boundary").attr("d", path);
});
});
</script>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment