Published
Edited
Apr 8, 2022
Fork of Orthographic
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map = {
const context = DOM.context2d(width, height);
const path = d3.geoPath(projection, context);
context.beginPath(), path(graticule), context.strokeStyle = "#ccc", context.stroke();
context.beginPath(), path(land), context.fillStyle = "#000", context.fill();
context.beginPath(), path(night), context.fillStyle = "rgba(0,0,255,0.3)", context.fill();
context.beginPath(), path(sphere), context.strokeStyle = "#000", context.stroke();
return context.canvas;
}
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height = {
const [[x0, y0], [x1, y1]] = d3.geoPath(projection.fitWidth(width, sphere)).bounds(sphere);
const dy = Math.ceil(y1 - y0), l = Math.min(Math.ceil(x1 - x0), dy);
projection.scale(projection.scale() * (l - 1) / l).precision(0.2);
return dy;
}
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projection = d3.geoNaturalEarth1()
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sun = {
const now = new Date;
const day = new Date(+now).setUTCHours(0, 0, 0, 0);
const t = solar.century(now);
const longitude = (day - now) / 864e5 * 360 - 180;
return [longitude - solar.equationOfTime(t) / 4, solar.declination(t)];
}
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night = d3.geoCircle()
.radius(90)
.center(antipode(sun))
()
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antipode = ([longitude, latitude]) => [longitude + 180, -latitude]
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sphere = ({type: "Sphere"})
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graticule = d3.geoGraticule10()
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land = topojson.feature(world, world.objects.land)
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world = fetch("https://cdn.jsdelivr.net/npm/world-atlas@2/land-50m.json").then(response => response.json())
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topojson = require("topojson-client@3")
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d3 = require("d3-geo@1")
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solar = require("solar-calculator@0.3/dist/solar-calculator.min.js")
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