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Last active February 9, 2016 01:26
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Icosahedron
license: gpl-3.0
<!DOCTYPE html>
<meta charset="utf-8">
<style>
.point {
fill: #000;
stroke: #fff;
}
.edge {
fill: none;
stroke: #000;
stroke-opacity: .4;
}
.face {
fill: #eee;
fill-rule: nonzero;
}
</style>
<body>
<script src="//d3js.org/d3.v3.min.js"></script>
<script>
var width = 960,
height = 500;
var velocity = [.018, .006];
var projection = d3.geo.orthographic()
.scale(240);
var path = d3.geo.path()
.projection({
stream: function(out) {
return {
point: function(x, y) { var p = projection([x, y]); out.point(p[0], p[1]); },
lineStart: function() { out.lineStart(); },
lineEnd: function() { out.lineEnd(); },
polygonStart: function() { out.polygonStart(); },
polygonEnd: function() { out.polygonEnd(); }
};
}
});
var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height);
var face = svg.selectAll(".face")
.data(icosahedron_faces)
.enter().append("path")
.attr("class", "face");
var edge = svg.append("path")
.datum(icosahedron_edges)
.attr("class", "edge");
var point = svg.append("path")
.datum(icosahedron_points)
.attr("class", "point");
d3.timer(function(elapsed) {
projection.rotate([elapsed * velocity[0], elapsed * velocity[1]]);
point.attr("d", path);
edge.attr("d", path);
face.attr("d", path);
});
function icosahedron_points() {
var points = [],
y = Math.atan2(1, 2) * 180 / Math.PI;
points.push([0, -90]);
for (var x = 0; x < 360; x += 36) {
points.push([x, -y], [x += 36, y]);
}
points.push([0, 90]);
return {type: "MultiPoint", coordinates: points};
}
function icosahedron_edges() {
var edges = [],
y = Math.atan2(1, 2) * 180 / Math.PI;
for (var x = 0; x < 360; x += 72) {
edges.push([[x + 0, -90], [x + 0, -y]]);
edges.push([[x + 0, -y], [x + 72, -y]]);
edges.push([[x + 36, y], [x - 36, y]]);
edges.push([[x + 36, y], [x + 0, -y]]);
edges.push([[x - 36, y], [x + 0, -y]]);
edges.push([[x + 36, 90], [x + 36, y]]);
}
return {type: "MultiLineString", coordinates: edges};
}
function icosahedron_faces() {
var faces = [],
y = Math.atan2(1, 2) * 180 / Math.PI;
for (var x = 0; x < 360; x += 72) {
faces.push([[[x + 0, -90], [x + 0, -y], [x + 72, -y], [x + 0, -90]]]);
faces.push([[[x + 0, -y], [x + 72, -y], [x + 36, y], [x + 0, -y]]]);
faces.push([[[x + 36, y], [x + 0, -y], [x - 36, y], [x + 36, y]]]);
faces.push([[[x - 36, 90], [x - 36, y], [x + 36, y], [x + 36, 90]]]);
}
return faces.map(function(face) {
return {type: "Polygon", coordinates: face};
});
}
</script>
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