Bounded Voronoi Tesselation using the algorithm described in xlr8r.info
See the variant: Circular Bounded Voronoi Tesselation.
Based on mbostock's block: Voronoi Tessellation
Author: Philippe Rivière, August 2016
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<meta charset="utf-8">
<style>
.links {
stroke: #000;
stroke-opacity: 0.2;
}
.polygons {
stroke: #000;
}
.polygons :first-child {
fill: #ff3d5a;
}
.sites {
fill: #666;
stroke: #fff;
}
.sites :first-child {
fill: #fff;
}
.convex-hull {
fill: none;
stroke: #fec1f4;
stroke-width: 2px;
}
</style>
<svg width="960" height="500"></svg>
<script src="https://d3js.org/d3.v4.min.js"></script>
<script src="https://d3js.org/d3-scale-chromatic.v1.min.js"></script>
<script>
var svg = d3.select("svg").on("touchmove mousemove", moved),
width = +svg.attr("width"),
height = +svg.attr("height"),
margin = 0.2; // 0 ≤ m < 0.5]
var color = d3.scaleOrdinal(d3.schemePastel1);
var sites = d3.range(100)
.map(function(d) { return [
width * (margin + Math.random() * (1 - 2 * margin)),
height * (margin + Math.random() * (1 - 2 * margin))
]; });
var voronoi = d3.voronoi()
.extent([[-1, -1], [width + 1, height + 1]]);
var polygon = svg.append("g")
.attr("class", "polygons");
var convexhull = svg.append('path')
.attr('class', 'convex-hull');
var link = svg.append("g")
.attr("class", "links");
var site = svg.append("g")
.attr("class", "sites");
redraw();
function moved() {
sites[0] = d3.mouse(this);
redraw();
}
function redraw() {
var links = voronoi.links(sites),
ext = d3.mean(links, function(l) {
var dx = l.source[0] - l.target[0],
dy = l.source[1] - l.target[1];
return Math.sqrt(dx*dx + dy*dy);
});
var convex = d3.polygonHull(sites);
convex.centroid = d3.polygonCentroid(convex);
convex = convex.map(function(p){
var dx = p[0] - convex.centroid[0],
dy = p[1] - convex.centroid[1],
angle = Math.atan2(dy, dx);
return [p[0] + Math.cos(angle) * ext, p[1] + Math.sin(angle) * ext];
});
var sites2 = sites.slice(); // clone
for (var i = 0; i < convex.length; i++) {
var n = convex[i], m = convex[i+1]||convex[0];
var dx = n[0] - m[0],
dy = n[1] - m[1],
dist = Math.sqrt(dx * dx + dy * dy);
var pts = Math.ceil(dist / 2 / ext);
for(var j=0; j <= pts; j++) {
var p = [m[0] + dx *j / pts, m[1] + dy * j / pts];
p.artificial = 1;
sites2.push(p);
}
}
var diagram = voronoi(sites2);
var p = polygon.selectAll("path")
.data(diagram.polygons());
p.enter().append("path").merge(p).call(redrawPolygon)
p.exit().remove();
var l = link
.selectAll("line")
.data(diagram.links().filter(function(l){
return !l.source.artificial && !l.target.artificial;
}));
l .enter()
.append("line")
.merge(l)
.call(redrawLink)
.exit()
.remove();
var s = site
.selectAll("circle")
.data(sites);
s.enter()
.append("circle")
.attr("r", 2.5)
.merge(s)
.call(redrawSite);
convexhull.attr('d', "M" + convex.join("L") + "Z");
}
function redrawPolygon(polygon) {
polygon
.attr("fill", function(d, i) {
return i < sites.length ? color(i) : '#faf6f1';
})
.attr("d", function(d) { return d ? "M" + d.join("L") + "Z" : null; });
}
function redrawLink(link) {
link
.attr("x1", function(d) { return d.source[0]; })
.attr("y1", function(d) { return d.source[1]; })
.attr("x2", function(d) { return d.target[0]; })
.attr("y2", function(d) { return d.target[1]; });
}
function redrawSite(site) {
site
.attr("cx", function(d) { return d[0]; })
.attr("cy", function(d) { return d[1]; });
}
</script>
https://d3js.org/d3.v4.min.js
https://d3js.org/d3-scale-chromatic.v1.min.js