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Last active June 1, 2018 20:05
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Projection face!
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<!DOCTYPE html>
<meta charset="utf-8">
<title>PROJECTION FACE</title>
<style>
body{ text-align: center }
</style>
<div id="map"></div>
<select id="projection-menu"></select>
<script src="http://d3js.org/d3.v3.min.js"></script>
<script src="http://d3js.org/d3.geo.projection.v0.min.js"></script>
<script src="http://d3js.org/d3.geo.polyhedron.v0.min.js"></script>
<script>
var ratio = window.devicePixelRatio || 1,
width = 960 * ratio,
height = 450 * ratio;
var options = [
{name: "Aitoff", projection: d3.geo.aitoff()},
{name: "Albers", projection: d3.geo.albers().scale(145).parallels([20, 50])},
{name: "August", projection: d3.geo.august().scale(60)},
{name: "Baker", projection: d3.geo.baker().scale(100)},
{name: "Berghaus", projection: d3.geo.berghaus().scale(100)},
{name: "Boggs", projection: d3.geo.boggs()},
{name: "Bonne", projection: d3.geo.bonne().scale(100)},
{name: "Bromley", projection: d3.geo.bromley()},
{name: "Collignon", projection: d3.geo.collignon().scale(93)},
{name: "Craster Parabolic", projection: d3.geo.craster()},
{name: "Eckert I", projection: d3.geo.eckert1().scale(165)},
{name: "Eckert II", projection: d3.geo.eckert2().scale(165)},
{name: "Eckert III", projection: d3.geo.eckert3().scale(180)},
{name: "Eckert IV", projection: d3.geo.eckert4().scale(180)},
{name: "Eckert V", projection: d3.geo.eckert5().scale(170)},
{name: "Eckert VI", projection: d3.geo.eckert6().scale(170)},
{name: "Eisenlohr", projection: d3.geo.eisenlohr().scale(60)},
{name: "Equirectangular (Plate Carrée)", projection: d3.geo.equirectangular()},
{name: "Fahey", projection: d3.geo.fahey().scale(120)},
{name: "Gall Stereographic", projection: d3.geo.cylindricalStereographic().parallel(45).scale(140)},
{name: "Goode Homolosine", projection: d3.geo.homolosine()},
{name: "Ginzburg IV", projection: d3.geo.ginzburg4().scale(120)},
{name: "Ginzburg V", projection: d3.geo.ginzburg5().scale(120)},
{name: "Ginzburg VI", projection: d3.geo.ginzburg6().scale(120)},
{name: "Ginzburg VIII", projection: d3.geo.ginzburg8().scale(120)},
{name: "Ginzburg IX", projection: d3.geo.ginzburg9().scale(120)},
{name: "Gringorten", projection: d3.geo.gringorten().scale(220)},
{name: "Guyou", projection: d3.geo.guyou().scale(150)},
{name: "Hammer", projection: d3.geo.hammer().scale(165)},
{name: "Hammer Retroazimuthal", projection: d3.geo.hammerRetroazimuthal().scale(90)},
{name: "HEALPix", projection: d3.geo.healpix()},
{name: "Hill", projection: d3.geo.hill().scale(120)},
{name: "Kavrayskiy VII", projection: d3.geo.kavrayskiy7()},
{name: "Lagrange", projection: d3.geo.lagrange().scale(120)},
{name: "Lambert cylindrical equal-area", projection: d3.geo.cylindricalEqualArea()},
{name: "Larrivée", projection: d3.geo.larrivee().scale(95)},
{name: "Laskowski", projection: d3.geo.laskowski().scale(120)},
{name: "Loximuthal", projection: d3.geo.loximuthal()},
{name: "Mercator", projection: d3.geo.mercator().scale(100)},
{name: "Miller", projection: d3.geo.miller().scale(100)},
{name: "McBryde–Thomas Flat-Polar Parabolic", projection: d3.geo.mtFlatPolarParabolic()},
{name: "McBryde–Thomas Flat-Polar Quartic", projection: d3.geo.mtFlatPolarQuartic()},
{name: "McBryde–Thomas Flat-Polar Sinusoidal", projection: d3.geo.mtFlatPolarSinusoidal()},
{name: "Mollweide", projection: d3.geo.mollweide().scale(165)},
{name: "Natural Earth", projection: d3.geo.naturalEarth()},
{name: "Nell–Hammer", projection: d3.geo.nellHammer()},
{name: "Orthographic", projection: d3.geo.orthographic().scale(200)},
{name: "Polyconic", projection: d3.geo.polyconic().scale(100)},
{name: "Rectangular Polyconic", projection: d3.geo.rectangularPolyconic().scale(120)},
{name: "Robinson", projection: d3.geo.robinson()},
{name: "Sinusoidal", projection: d3.geo.sinusoidal()},
{name: "Sinu-Mollweide", projection: d3.geo.sinuMollweide()},
{name: "Stereographic", projection: d3.geo.stereographic()},
{name: "Times", projection: d3.geo.times().scale(140)},
{name: "Van der Grinten", projection: d3.geo.vanDerGrinten().scale(75)},
{name: "Van der Grinten II", projection: d3.geo.vanDerGrinten2().scale(75)},
{name: "Van der Grinten III", projection: d3.geo.vanDerGrinten3().scale(75)},
{name: "Van der Grinten IV", projection: d3.geo.vanDerGrinten4().scale(120)},
{name: "Wagner IV", projection: d3.geo.wagner4()},
{name: "Wagner VI", projection: d3.geo.wagner6()},
{name: "Wagner VII", projection: d3.geo.wagner7()},
{name: "Waterman", projection: d3.geo.polyhedron.waterman().scale(70)},
{name: "Winkel Tripel", projection: d3.geo.winkel3()}
];
var menu = d3.select("#projection-menu")
.on("change", change);
menu.selectAll("option")
.data(options)
.enter().append("option")
.text(function(d) { return d.name; });
function change() {
update(options[this.selectedIndex]);
}
var i = 0,
n = options.length - 1;
rando();
var projection = options[i].projection;
options.forEach(function(option) {
option.projection
.translate([width / 2, height / 2])
.scale(option.projection.scale() * ratio)
.clipExtent([[2 * ratio, 2 * ratio], [width - 2 * ratio, height - 2 * ratio]]);
});
var graticule = d3.geo.graticule()(),
face,
boundaries;
var canvas = d3.select("#map").append("canvas")
.attr("width", width)
.attr("height", height)
.style("width", width / ratio + "px")
.style("height", height / ratio + "px");
var context = canvas.node().getContext("2d");
context.fillStyle = "#f9f9f9";
context.strokeStyle = "#000";
var path = d3.geo.path()
.projection(projection)
.context(context);
function rando() {
var j = Math.floor(Math.random() * n);
i = j + (j >= i);
menu.property("selectedIndex", i = j + (j >= i));
}
function change() {
update(options[this.selectedIndex]);
}
function pathTween(projection0, projection1) {
var t = 0,
projection = d3.geo.projection(function(λ, φ) {
λ *= 180 / Math.PI, φ *= 180 / Math.PI;
var p0 = projection0([λ, φ]), p1 = projection1([λ, φ]);
return [(1 - t) * p0[0] + t * p1[0], (1 - t) * -p0[1] + t * -p1[1]];
})
.scale(1)
.translate([width / 2, height / 2])
.clipExtent(projection0.clipExtent()),
path = d3.geo.path().projection(projection).context(context);
return function() {
return function(u) {
t = u;
redraw(path);
};
};
}
function update(option) {
canvas.transition()
.duration(750)
.ease( d3.ease("quad") )
.tween("path", pathTween(projection, projection = option.projection));
path.projection(projection);
}
function redraw(path) {
context.clearRect(0, 0, width, height);
context.lineWidth = .5 * ratio;
context.strokeStyle = "#999";
context.beginPath(), path(graticule), context.stroke();
context.beginPath(), path({type: "Sphere"}), context.stroke();
context.lineWidth = 2 * ratio;
if (face) {
context.strokeStyle = "#000";
context.lineWidth = 2;
context.beginPath(), path(face), context.stroke();
}
}
d3.json("/awoodruff/raw/9216081/face.geojson", function(error, data) {
face = data;
redraw(path)
});
</script>
</body>
</html>
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