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Ocean
license: gpl-3.0
redirect: https://observablehq.com/@d3/oceans
build
node_modules

One of the few cases where you want a counterclockwise polygon because the ocean covers greater than one hemisphere. The example demonstrates improved antimeridian stitching in TopoJSON 1.4.1.

<!DOCTYPE html>
<meta charset="utf-8">
<style>
body {
background: #fcfcfa;
}
</style>
<body>
<script src="//d3js.org/d3.v3.min.js"></script>
<script src="//d3js.org/topojson.v1.min.js"></script>
<script>
var width = 960,
height = 960,
speed = 1e-2,
start = Date.now();
var sphere = {type: "Sphere"};
var projection = d3.geo.orthographic()
.scale(width / 2.2)
.clipAngle(90)
.translate([width / 2, height / 2])
.precision(.5);
var graticule = d3.geo.graticule();
var canvas = d3.select("body").append("canvas")
.attr("width", width)
.attr("height", height);
var context = canvas.node().getContext("2d");
var path = d3.geo.path()
.projection(projection)
.context(context);
d3.json("topo.json", function(error, topo) {
if (error) throw error;
var ocean = topojson.feature(topo, topo.objects.ocean),
grid = graticule();
d3.timer(function() {
projection.rotate([speed * (Date.now() - start), -15]);
context.clearRect(0, 0, width, height);
context.beginPath();
path(sphere);
context.fillStyle = "#fff";
context.fill();
context.beginPath();
path(grid);
context.lineWidth = .5;
context.strokeStyle = "#ddd";
context.stroke();
context.beginPath();
path(ocean);
context.fillStyle = "rgba(70,130,180,.5)";
context.fill();
context.beginPath();
path(sphere);
context.lineWidth = 1.5;
context.strokeStyle = "#000";
context.stroke();
});
});
d3.select(self.frameElement).style("height", height + "px");
</script>
all: topo.json
build/ne_%_ocean.zip:
mkdir -p build
curl -o $@ --raw 'http://www.nacis.org/naturalearth/$*/physical/ne_$*_ocean.zip'
build/ne_%.shp: build/ne_%.zip
unzip -d build $<
touch $@
topo.json: build/ne_110m_ocean.shp
node_modules/.bin/topojson \
--no-force-clockwise \
-q 1e5 \
-- \
ocean=build/ne_110m_ocean.shp \
> $@
{
"name": "anonymous",
"version": "0.0.1",
"private": true,
"devDependencies": {
"topojson": "1"
}
}
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