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@codybuell /README.md
Last active Aug 29, 2015

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Colored Delaunay Triangulation Mk I
<!DOCTYPE html>
<head>
<meta charset="utf-8">
<style>
body {
font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
width: 960px;
height: 500px;
position: relative;
background-color: #555;
}
</style>
</head>
<body>
<script src="http://d3js.org/d3.v3.min.js"></script>
<script>
// define sizes counts opacities and colors
var width = 960,
height = 500,
cellsize = 150, // average cell size
cellpadding = 15, // minimum distance between nodes
bleed = 250, // how far outside element to generate nodes
fillopacity = 0.50,
strokeopacity = 0.50,
cellsX = Math.ceil((width+bleed*2)/cellsize),
cellsY = Math.ceil((height+bleed*2)/cellsize),
x_gradient = ['#333', '#87afaf', '#af5f5f', '#565656'],
y_gradient = ['#87afd7', '#af5f5f', '#333'];
// generate random data set to fill window and a bit beyond
var nodes = d3.range(cellsX*cellsY).map(function(d) {
var col = d % cellsX;
var row = Math.floor(d / cellsX);
var x = Math.round(-bleed + col*cellsize + Math.random() * (cellsize - cellpadding*2) + cellpadding);
var y = Math.round(-bleed + row*cellsize + Math.random() * (cellsize - cellpadding*2) + cellpadding);
return [x, y];
});
// color iterpolation / generation based on cell centroid
function color(x, y) {
var color_x = d3.scale.linear()
.range(x_gradient)
.domain(d3.range(0, width, width/x_gradient.length)); //[-bleed, width+bleed]
var color_y = d3.scale.linear()
.range(y_gradient)
.domain(d3.range(0, height, height/y_gradient.length)); //[-bleed, width+bleed]
return d3.interpolateRgb(color_x(x), color_y(y))(0.5);
}
// generate and place svg container
var svg = d3.select('body').append('svg')
.attr('id', 'voronoi')
.attr('width', width)
.attr('height', height)
.on("mousemove", function() { nodes[0] = d3.mouse(this); draw(); });
// define triangle voronoi
var voronoi = d3.geom.voronoi()
.clipExtent([[cellpadding, cellpadding], [width - cellpadding, height - cellpadding]])
.triangles(nodes);
// define paths
var path = svg.append("g").selectAll("path");
// initial rendering
draw();
// draw the triangles
function draw() {
path = path.data(d3.geom.voronoi().triangles(nodes).map(function(d) { return "M" + d.join("L") + "Z"; }), String);
path.enter().append("path")
.style('fill', function(d, i) {
var c = d.replace(/M/g,'').replace(/Z/g,'').replace(/L/g,',');
var c = c.split(',');
var x = (parseFloat(c[0]) + parseFloat(c[2]) + parseFloat(c[4]))/3;
var y = (parseFloat(c[1]) + parseFloat(c[3]) + parseFloat(c[5]))/3;
return color(x, y);
})
. style('stroke', function(d,i) {
var c = d.replace(/M/g,'').replace(/Z/g,'').replace(/L/g,',');
var c = c.split(',');
var x = (parseFloat(c[0]) + parseFloat(c[2]) + parseFloat(c[4]))/3;
var y = (parseFloat(c[1]) + parseFloat(c[3]) + parseFloat(c[5]))/3;
return color(x, y);
})
.style('fill-opacity', function(d,i) {
if (fillopacity != 1)
return fillopacity;
})
.style('stroke-opacity', function(d,i) {
if (strokeopacity != 1)
return strokeopacity;
})
.attr("d", String);
path.exit().remove();
}
</script>
</body>
</html>
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