Published
Edited
Aug 27, 2020
Fork of U.S. Map
11 forks
Importers
13 stars
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projection = geoAlbersUsaPr().scale(1300).translate([487.5, 305])
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map = html`<svg viewBox="0 0 975 610">
<g fill="none" stroke="#000" stroke-linejoin="round" stroke-linecap="round">
<path stroke="#aaa" stroke-width="0.5" d="${path(topojson.mesh(us, us.objects.counties, (a, b) => a !== b && (a.id / 1000 | 0) === (b.id / 1000 | 0)))}"></path>
<path stroke-width="0.5" d="${path(topojson.mesh(us, us.objects.states, (a, b) => a !== b))}"></path>
<path d="${path(topojson.feature(us, us.objects.nation))}"></path>
</g>
</svg>`
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path = d3.geoPath(projection)
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function geoAlbersUsaPr() {
var cache,
cacheStream,
lower48 = d3.geoAlbers(), lower48Point,
alaska = d3.geoConicEqualArea().rotate([154, 0]).center([-2, 58.5]).parallels([55, 65]),
alaskaPoint,
hawaii = d3.geoConicEqualArea().rotate([157, 0]).center([-3, 19.9]).parallels([8, 18]),
hawaiiPoint,
puertoRico = d3.geoConicEqualArea().rotate([66, 0]).center([0, 18]).parallels([8, 18]),
puertoRicoPoint,
point,
pointStream = {point: function(x, y) { point = [x, y]; }};

function albersUsa(coordinates) {
var x = coordinates[0], y = coordinates[1];
return point = null,
(lower48Point.point(x, y), point)
|| (alaskaPoint.point(x, y), point)
|| (hawaiiPoint.point(x, y), point)
|| (puertoRicoPoint.point(x, y), point);
}

albersUsa.invert = function(coordinates) {
var k = lower48.scale(),
t = lower48.translate(),
x = (coordinates[0] - t[0]) / k,
y = (coordinates[1] - t[1]) / k;
return (y >= 0.120 && y < 0.234 && x >= -0.425 && x < -0.214 ? alaska
: y >= 0.166 && y < 0.234 && x >= -0.214 && x < -0.115 ? hawaii
: y >= 0.204 && y < 0.234 && x >= 0.320 && x < 0.380 ? puertoRico
: lower48).invert(coordinates);
};

albersUsa.stream = function(stream) {
return cache && cacheStream === stream ? cache : cache = multiplex([lower48.stream(cacheStream = stream), alaska.stream(stream), hawaii.stream(stream), puertoRico.stream(stream)]);
};

albersUsa.precision = function(_) {
if (!arguments.length) return lower48.precision();
lower48.precision(_), alaska.precision(_), hawaii.precision(_), puertoRico.precision(_);
return reset();
};

albersUsa.scale = function(_) {
if (!arguments.length) return lower48.scale();
lower48.scale(_), alaska.scale(_ * 0.35), hawaii.scale(_), puertoRico.scale(_);
return albersUsa.translate(lower48.translate());
};

albersUsa.translate = function(_) {
if (!arguments.length) return lower48.translate();
var k = lower48.scale(), x = +_[0], y = +_[1];

lower48Point = lower48
.translate(_)
.clipExtent([[x - 0.455 * k, y - 0.238 * k], [x + 0.455 * k, y + 0.238 * k]])
.stream(pointStream);

alaskaPoint = alaska
.translate([x - 0.307 * k, y + 0.201 * k])
.clipExtent([[x - 0.425 * k + epsilon, y + 0.120 * k + epsilon], [x - 0.214 * k - epsilon, y + 0.234 * k - epsilon]])
.stream(pointStream);

hawaiiPoint = hawaii
.translate([x - 0.205 * k, y + 0.212 * k])
.clipExtent([[x - 0.214 * k + epsilon, y + 0.166 * k + epsilon], [x - 0.115 * k - epsilon, y + 0.234 * k - epsilon]])
.stream(pointStream);

puertoRicoPoint = puertoRico
.translate([x + 0.350 * k, y + 0.224 * k])
.clipExtent([[x + 0.320 * k, y + 0.204 * k], [x + 0.380 * k, y + 0.234 * k]])
.stream(pointStream).point;

return reset();
};

function reset() {
cache = cacheStream = null;
return albersUsa;
}

return albersUsa.scale(1070);
}
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function multiplex(streams) {
const n = streams.length;
return {
point(x, y) { for (const s of streams) s.point(x, y); },
sphere() { for (const s of streams) s.sphere(); },
lineStart() { for (const s of streams) s.lineStart(); },
lineEnd() { for (const s of streams) s.lineEnd(); },
polygonStart() { for (const s of streams) s.polygonStart(); },
polygonEnd() { for (const s of streams) s.polygonEnd(); }
};
}
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epsilon = 1e-6
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us = FileAttachment("counties-10m.json").json()
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topojson = require("topojson-client@3")
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d3 = require("d3-geo@2")
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