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@jonathanmoore
Forked from christophermanning/README.md
Created November 8, 2012 07:55
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Voronoi Diagram with Force Directed Nodes and Delaunay Links
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html;charset=utf-8"/>
<script type="text/javascript" src="http://mbostock.github.com/d3/d3.v2.min.js"></script>
<link rel="stylesheet" href="http://mbostock.github.com/d3/ex/colorbrewer.css">
<style type="text/css">
circle {
stroke: #EFEDF5;
fill: #EFEDF5;
}
line {
stroke: #EFEDF5;
pointer-events: none
}
path{
stroke: black
}
</style>
</head>
<body>
<div id="chart">
</div>
<script type="text/javascript">
var w = 1200,
h = 400,
links = [],
voronoiVertices = [],
color = d3.scale.quantize().domain([7000, 10000]).range(d3.range(2, 9));
var numVertices = 100;
var vertices = d3.range(numVertices).map(function(d) { return {x: d.x, y: d.y}; })
var prevEventScale = 1;
var zoom = d3.behavior.zoom().on("zoom", function(d,i) {
if (d3.event.scale > prevEventScale) {
vertices.push(function(d) { return {x: d.x, y: d.y}; })
} else if (vertices.length > 2) {
vertices.pop();
}
force.nodes(vertices).start()
prevEventScale = d3.event.scale;
});
var svg = d3.select("#chart")
.append("svg")
.attr("width", w)
.attr("height", h)
.attr("class", "Purples")
.call(zoom)
var force = self.force = d3.layout.force()
.charge(-300)
.size([w, h])
.on("tick", update);
force.nodes(vertices).start();
var circle = svg.selectAll("circle");
var path = svg.selectAll("path");
var link = svg.selectAll("line");
function update(e) {
voronoiVertices = vertices.map(function(o){return [o.x, o.y, o]})
path = path.data(d3.geom.voronoi(voronoiVertices))
path.enter().insert("path", "path") //group all the path elements first so they have the lowest z-order
.attr("class", function(d, i) { return "q"+color(d3.geom.polygon(d).area())+"-9"; })
.attr("d", function(d) { return "M" + d.join("L") + "Z"; });
path.attr("class", function(d, i) { return "q"+color(d3.geom.polygon(d).area())+"-9"; })
.attr("d", function(d) { return "M" + d.join("L") + "Z"; });
path.exit().remove();
circle = circle.data(vertices)
circle.enter().append("circle")
.call(force.drag)
.attr("r", 0)
.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; })
.transition().duration(1000).attr("r", 5);
circle.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; });
circle.exit().transition().attr("r", 0).remove();
links = []
d3.geom.delaunay(voronoiVertices).forEach(function(d) {
links.push(edge(d[0], d[1]));
links.push(edge(d[1], d[2]));
links.push(edge(d[2], d[0]));
});
link = link.data(links)
link.enter().append("line")
link.attr("x1", function(d) { return d.source[2].x; })
.attr("y1", function(d) { return d.source[2].y; })
.attr("x2", function(d) { return d.target[2].x; })
.attr("y2", function(d) { return d.target[2].y; })
link.exit().remove()
}
function edge(a, b) {
return {
source: a,
target: b
};
}
</script>
</body>
</html>
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