Skip to content

Instantly share code, notes, and snippets.

@mbostock

mbostock/.block

Last active February 9, 2016 01:49
Show Gist options
  • Save mbostock/4a21fbfe0d5cb6690ed4 to your computer and use it in GitHub Desktop.
Save mbostock/4a21fbfe0d5cb6690ed4 to your computer and use it in GitHub Desktop.
Download ZIP
Delaunay Circles II
Raw
.block
license: gpl-3.0
Raw
index.html
<!DOCTYPE html>
<meta charset="utf-8">
<canvas width="960" height="500"></canvas>
<script>
/* https://github.com/d3/d3-voronoi Copyright 2015 Mike Bostock */
!function(e,t){"object"==typeof exports&&"undefined"!=typeof module?t(exports):"function"==typeof define&&define.amd?define(["exports"],t):t(e.voronoi={})}(this,function(e){"use strict";function t(e){return function(){return e}}function n(e,t,n){return(e.x-n.x)*(t.y-e.y)-(e.x-t.x)*(n.y-e.y)}function i(e,t){return t.angle-e.angle}function r(e,t){this.l=e,this.r=t,this.a=this.b=null}function s(e,t,n){var i=new r(e,null);return i.a=t,i.b=n,D.push(i),i}function u(e,t,n){this.edge=e,this.site=t,this.angle=n}function f(e,t,n){var i=e.a,r=e.b;return new u(e,t,n?Math.atan2(n.y-t.y,n.x-t.x):e.l===t?Math.atan2(r.x-i.x,i.y-r.y):Math.atan2(i.x-r.x,r.y-i.y))}function a(e,t,n,i){for(var r,u,a,l,o,c,h,y,x,v,g=B.length;g--;)if(o=B[g],o&&o.prepare())for(h=o.edges,y=h.length,c=0;y>c;)v=h[c].end(),a=v.x,l=v.y,x=h[++c%y].start(),r=x.x,u=x.y,(Math.abs(a-r)>I||Math.abs(l-u)>I)&&(h.splice(c,0,f(s(o.site,v,Math.abs(a-e)<I&&i-l>I?{x:e,y:Math.abs(r-e)<I?u:i}:Math.abs(l-i)<I&&n-a>I?{x:Math.abs(u-i)<I?r:n,y:i}:Math.abs(a-n)<I&&l-t>I?{x:n,y:Math.abs(r-n)<I?u:t}:Math.abs(l-t)<I&&a-e>I?{x:Math.abs(u-t)<I?r:e,y:t}:null),o.site,null)),++y)}function l(e,t,n,i,r){var s,u=e.a,f=e.b,a=u.x,l=u.y,o=f.x,c=f.y,h=0,y=1,x=o-a,v=c-l;if(s=t-a,x||!(s>0)){if(s/=x,0>x){if(h>s)return;y>s&&(y=s)}else if(x>0){if(s>y)return;s>h&&(h=s)}if(s=i-a,x||!(0>s)){if(s/=x,0>x){if(s>y)return;s>h&&(h=s)}else if(x>0){if(h>s)return;y>s&&(y=s)}if(s=n-l,v||!(s>0)){if(s/=v,0>v){if(h>s)return;y>s&&(y=s)}else if(v>0){if(s>y)return;s>h&&(h=s)}if(s=r-l,v||!(0>s)){if(s/=v,0>v){if(s>y)return;s>h&&(h=s)}else if(v>0){if(h>s)return;y>s&&(y=s)}return h>0&&(e.a={x:a+h*x,y:l+h*v}),1>y&&(e.b={x:a+y*x,y:l+y*v}),e}}}}}function o(e,t,n,i,r){var s=e.b;if(s)return!0;var u,f,a=e.a,l=e.l,o=e.r,c=l.x,h=l.y,y=o.x,x=o.y,v=(c+y)/2,g=(h+x)/2;if(x===h){if(t>v||v>=i)return;if(c>y){if(a){if(a.y>=r)return}else a={x:v,y:n};s={x:v,y:r}}else{if(a){if(a.y<n)return}else a={x:v,y:r};s={x:v,y:n}}}else if(u=(c-y)/(x-h),f=g-u*v,-1>u||u>1)if(c>y){if(a){if(a.y>=r)return}else a={x:(n-f)/u,y:n};s={x:(r-f)/u,y:r}}else{if(a){if(a.y<n)return}else a={x:(r-f)/u,y:r};s={x:(n-f)/u,y:n}}else if(x>h){if(a){if(a.x>=i)return}else a={x:t,y:u*t+f};s={x:i,y:u*i+f}}else{if(a){if(a.x<t)return}else a={x:i,y:u*i+f};s={x:t,y:u*t+f}}return e.a=a,e.b=s,!0}function c(e,t,n,i){for(var r,s=D.length;s--;)r=D[s],(!o(r,e,t,n,i)||!l(r,e,t,n,i)||Math.abs(r.a.x-r.b.x)<I&&Math.abs(r.a.y-r.b.y)<I)&&(r.a=r.b=null,D.splice(s,1))}function h(e){e.U=e.C=e.L=e.R=e.P=e.N=null}function y(e){var t=e.circle;t&&(t.P||(J=t.N),F.remove(t),K.push(t),h(t),e.circle=null)}function x(){h(this),this.x=this.y=this.arc=this.site=this.cy=null}function v(e){var t=e.P,n=e.N;if(t&&n){var i=t.site,r=e.site,s=n.site;if(i!==s){var u=r.x,f=r.y,a=i.x-u,l=i.y-f,o=s.x-u,c=s.y-f,h=2*(a*c-l*o);if(!(h>=-O)){var y=a*a+l*l,v=o*o+c*c,g=(c*y-l*v)/h,C=(a*v-o*y)/h,c=C+f,d=K.pop()||new x;d.arc=e,d.site=r,d.x=g+u,d.y=c+Math.sqrt(g*g+C*C),d.cy=c,e.circle=d;for(var p=null,L=F._;L;)if(d.y<L.y||d.y===L.y&&d.x<=L.x){if(!L.L){p=L.P;break}L=L.L}else{if(!L.R){p=L;break}L=L.R}F.insert(p,d),p||(J=d)}}}}function g(e,t,n,i){e.a||e.b?e.l===n?e.b=i:e.a=i:(e.a=i,e.l=t,e.r=n)}function C(e,t,n,i){var s=new r(e,t);return D.push(s),n&&g(s,e,t,n),i&&g(s,t,e,i),B[e.i].edges.push(f(s,e,t)),B[t.i].edges.push(f(s,t,e)),s}function d(){h(this),this.edge=this.site=this.circle=null}function p(e){var t=Q.pop()||new d;return t.site=e,t}function L(e){y(e),G.remove(e),Q.push(e),h(e)}function b(e){var t=e.circle,n=t.x,i=t.cy,r={x:n,y:i},s=e.P,u=e.N,f=[e];L(e);for(var a=s;a.circle&&Math.abs(n-a.circle.x)<I&&Math.abs(i-a.circle.cy)<I;)s=a.P,f.unshift(a),L(a),a=s;f.unshift(a),y(a);for(var l=u;l.circle&&Math.abs(n-l.circle.x)<I&&Math.abs(i-l.circle.cy)<I;)u=l.N,f.push(l),L(l),l=u;f.push(l),y(l);var o,c=f.length;for(o=1;c>o;++o)l=f[o],a=f[o-1],g(l.edge,a.site,l.site,r);a=f[0],l=f[c-1],l.edge=C(a.site,l.site,null,r),v(a),v(l)}function R(e){this.site=e,this.edges=[]}function M(e){return B[e.i]=new R(e)}function U(e,t){var n=e.site,i=n.x,r=n.y,s=r-t;if(!s)return i;var u=e.P;if(!u)return-(1/0);n=u.site;var f=n.x,a=n.y,l=a-t;if(!l)return f;var o=f-i,c=1/s-1/l,h=o/l;return c?(-h+Math.sqrt(h*h-2*c*(o*o/(-2*l)-a+l/2+r-s/2)))/c+i:(i+f)/2}function N(e,t){var n=e.N;if(n)return U(n,t);var i=e.site;return i.y===t?i.x:1/0}function P(e){for(var t,n,i,r,s=e.x,u=e.y,f=G._;f;)if(i=U(f,u)-s,i>I)f=f.L;else{if(r=s-N(f,u),!(r>I)){i>-I?(t=f.P,n=f):r>-I?(t=f,n=f.N):t=n=f;break}if(!f.R){t=f;break}f=f.R}M(e);var a=p(e);if(G.insert(t,a),t||n){if(t===n)return y(t),n=p(t.site),G.insert(a,n),a.edge=n.edge=C(t.site,a.site),v(t),void v(n);if(!n)return void(a.edge=C(t.site,a.site));y(t),y(n);var l=t.site,o=l.x,c=l.y,h=e.x-o,x=e.y-c,d=n.site,L=d.x-o,b=d.y-c,R=2*(h*b-x*L),P=h*h+x*x,_=L*L+b*b,m={x:(b*P-x*_)/R+o,y:(h*_-L*P)/R+c};g(n.edge,l,d,m),a.edge=C(l,e,null,m),n.edge=C(e,d,null,m),v(t),v(n)}}function _(){this._=null}function m(e,t){var n=t,i=t.L,r=n.U;r?r.L===n?r.L=i:r.R=i:e._=i,i.U=r,n.U=i,n.L=i.R,n.L&&(n.L.U=n),i.R=n}function w(e,t){var n=t,i=t.R,r=n.U;r?r.L===n?r.L=i:r.R=i:e._=i,i.U=r,n.U=i,n.R=i.L,n.R&&(n.R.U=n),i.L=n}function k(e){for(;e.L;)e=e.L;return e}function q(e,t){return t.y-e.y||t.x-e.x}function A(e,t){var n,i,r,s=e.sort(q).pop();for(D=[],B=new Array(e.length),G=new _,F=new _;;)if(r=J,s&&(!r||s.y<r.y||s.y===r.y&&s.x<r.x))(s.x!==n||s.y!==i)&&(P(s),n=s.x,i=s.y),s=e.pop();else{if(!r)break;b(r.arc)}if(t){var n=t[0][0],i=t[0][1],u=t[1][0],f=t[1][1];c(n,i,u,f),a(n,i,u,f)}var l={cells:B,edges:D};return G=F=D=B=null,l}function E(e){return e[1]}function j(e){return e[0]}function z(){function e(e){var t=new Array(e.length),n=l[0][0],i=l[0][1],s=l[1][0],u=l[1][1];return A(r(e),l).cells.forEach(function(r,f){var a=r.edges,l=r.site,o=t[f]=a.length?a.map(function(e){var t=e.start();return[t.x,t.y]}):l.x>=n&&l.x<=s&&l.y>=i&&l.y<=u?[[n,u],[s,u],[s,i],[n,i]]:[];o.point=e[f]}),t}function r(e){return e.map(function(e,t){return{x:Math.round(f(e,t)/I)*I,y:Math.round(a(e,t)/I)*I,i:t}})}var s=j,u=E,f=s,a=u,l=H;return e.links=function(e){return A(r(e)).edges.filter(function(e){return e.l&&e.r}).map(function(t){return{source:e[t.l.i],target:e[t.r.i]}})},e.triangles=function(e){var t=[];return A(r(e)).cells.forEach(function(r,s){for(var u,f,a=r.site,l=r.edges.sort(i),o=-1,c=l.length,h=l[c-1].edge,y=h.l===a?h.r:h.l;++o<c;)u=h,f=y,h=l[o].edge,y=h.l===a?h.r:h.l,s<f.i&&s<y.i&&n(a,f,y)<0&&t.push([e[s],e[f.i],e[y.i]])}),t},e.x=function(n){return arguments.length?(s=n,f="function"==typeof n?s:t(s),e):s},e.y=function(n){return arguments.length?(u=n,a="function"==typeof n?u:t(u),e):u},e.extent=function(t){return arguments.length?(l=null==t?H:t,e):l===H?null:l},e.size=function(t){return arguments.length?e.extent(t&&[[0,0],t]):l===H?null:l&&l[1]},e}var B,D,F,G,H=[[-1e6,-1e6],[1e6,1e6]],I=1e-6;u.prototype={start:function(){return this.edge.l===this.site?this.edge.a:this.edge.b},end:function(){return this.edge.l===this.site?this.edge.b:this.edge.a}};var J,K=[],O=1e-12,Q=[];R.prototype.prepare=function(){for(var e,t=this.edges,n=t.length;n--;)e=t[n].edge,e.b&&e.a||t.splice(n,1);return t.sort(i),t.length},_.prototype={insert:function(e,t){var n,i,r;if(e){if(t.P=e,t.N=e.N,e.N&&(e.N.P=t),e.N=t,e.R){for(e=e.R;e.L;)e=e.L;e.L=t}else e.R=t;n=e}else this._?(e=k(this._),t.P=null,t.N=e,e.P=e.L=t,n=e):(t.P=t.N=null,this._=t,n=null);for(t.L=t.R=null,t.U=n,t.C=!0,e=t;n&&n.C;)i=n.U,n===i.L?(r=i.R,r&&r.C?(n.C=r.C=!1,i.C=!0,e=i):(e===n.R&&(w(this,n),e=n,n=e.U),n.C=!1,i.C=!0,m(this,i))):(r=i.L,r&&r.C?(n.C=r.C=!1,i.C=!0,e=i):(e===n.L&&(m(this,n),e=n,n=e.U),n.C=!1,i.C=!0,w(this,i))),n=e.U;this._.C=!1},remove:function(e){e.N&&(e.N.P=e.P),e.P&&(e.P.N=e.N),e.N=e.P=null;var t,n,i,r=e.U,s=e.L,u=e.R;if(n=s?u?k(u):s:u,r?r.L===e?r.L=n:r.R=n:this._=n,s&&u?(i=n.C,n.C=e.C,n.L=s,s.U=n,n!==u?(r=n.U,n.U=e.U,e=n.R,r.L=e,n.R=u,u.U=n):(n.U=r,r=n,e=n.R)):(i=e.C,e=n),e&&(e.U=r),!i){if(e&&e.C)return void(e.C=!1);do{if(e===this._)break;if(e===r.L){if(t=r.R,t.C&&(t.C=!1,r.C=!0,w(this,r),t=r.R),t.L&&t.L.C||t.R&&t.R.C){t.R&&t.R.C||(t.L.C=!1,t.C=!0,m(this,t),t=r.R),t.C=r.C,r.C=t.R.C=!1,w(this,r),e=this._;break}}else if(t=r.L,t.C&&(t.C=!1,r.C=!0,m(this,r),t=r.L),t.L&&t.L.C||t.R&&t.R.C){t.L&&t.L.C||(t.R.C=!1,t.C=!0,w(this,t),t=r.L),t.C=r.C,r.C=t.L.C=!1,m(this,r),e=this._;break}t.C=!0,e=r,r=r.U}while(!e.C);e&&(e.C=!1)}}},e.voronoi=z});
/* https://github.com/d3/d3-timer Copyright 2015 Mike Bostock */
"undefined"==typeof requestAnimationFrame&&(requestAnimationFrame="undefined"!=typeof window&&(window.msRequestAnimationFrame||window.mozRequestAnimationFrame||window.webkitRequestAnimationFrame||window.oRequestAnimationFrame)||function(e){return setTimeout(e,17)}),function(e,n){"object"==typeof exports&&"undefined"!=typeof module?n(exports):"function"==typeof define&&define.amd?define(["exports"],n):n(e.timer={})}(this,function(e){"use strict";function n(){r=m=0,c=1/0,t(u())}function t(e){if(!r){var t=e-Date.now();t>24?c>e&&(m&&clearTimeout(m),m=setTimeout(n,t),c=e):(m&&(m=clearTimeout(m),c=1/0),r=requestAnimationFrame(n))}}function i(e,n,i){i=null==i?Date.now():+i,null!=n&&(i+=+n);var o={callback:e,time:i,flush:!1,next:null};a?a.next=o:f=o,a=o,t(i)}function o(e,n,t){t=null==t?Date.now():+t,null!=n&&(t+=+n),l.callback=e,l.time=t}function u(e){e=null==e?Date.now():+e;var n=l;for(l=f;l;)e>=l.time&&(l.flush=l.callback(e-l.time,e)),l=l.next;l=n,e=1/0;for(var t,i=f;i;)i.flush?i=t?t.next=i.next:f=i.next:(i.time<e&&(e=i.time),i=(t=i).next);return a=t,e}var a,m,r,f,l,c=1/0;e.timer=i,e.timerReplace=o,e.timerFlush=u});
var canvas = document.querySelector("canvas"),
width = canvas.width,
height = canvas.height,
context = canvas.getContext("2d"),
voro = voronoi.voronoi().extent([[1, 1], [width - 1, height - 1]]);
var n = 200,
particles = new Array(n),
radius = 10;
for (var i = 0; i < n; ++i) particles[i] = {0: Math.random() * width, 1: Math.random() * height, vx: 0, vy: 0};
for (var i = 0; i <= width; i += 80) particles.push([i, 0], [i, height]);
for (var i = 0; i <= height; i += 80) particles.push([0, i], [width, i]);
timer.timer(function(elapsed) {
for (var i = 0; i < n; ++i) {
var p = particles[i];
p[0] += p.vx; if (p[0] < 0) p[0] += width; else if (p[0] > width) p[0] -= width;
p[1] += p.vy; if (p[1] < 0) p[1] += height; else if (p[1] > height) p[1] -= height;
p.vx += 0.1 * (Math.random() - .5) - 0.01 * p.vx;
p.vy += 0.1 * (Math.random() - .5) - 0.01 * p.vy;
}
var triangles = voro.triangles(particles);
context.clearRect(0, 0, width, height);
context.beginPath();
triangles.forEach(function(t) { drawTriangle(t[0][0], t[0][1], t[1][0], t[1][1], t[2][0], t[2][1]); });
context.strokeStyle = "#aaa";
context.stroke();
context.beginPath();
triangles.forEach(function(t) { drawRoundedTriangle(t[0][0], t[0][1], t[1][0], t[1][1], t[2][0], t[2][1], radius); });
context.fillStyle = "#eee";
context.fill();
context.strokeStyle = "#000";
context.stroke();
context.beginPath();
particles.forEach(function(p) { drawParticle(p[0], p[1]); });
context.fillStyle = "#000";
context.fill();
});
function drawParticle(x, y) {
context.moveTo(x + 2, y);
context.arc(x, y, 2, 0, 2 * Math.PI);
}
function drawTriangle(x0, y0, x1, y1, x2, y2) {
context.moveTo(x0, y0);
context.lineTo(x1, y1);
context.lineTo(x2, y2);
context.closePath();
}
function drawRoundedTriangle(x0, y0, x1, y1, x2, y2, r) {
var circle = inscribeTriangle(x0, y0, x1, y1, x2, y2);
if (circle.radius <= r) {
context.moveTo(circle[0] + circle.radius, circle[1]);
context.arc(circle[0], circle[1], circle.radius, 0, 2 * Math.PI);
} else {
var p0 = closestPoint(circle[0], circle[1], x0, y0, x1, y1),
p1 = closestPoint(circle[0], circle[1], x1, y1, x2, y2),
p2 = closestPoint(circle[0], circle[1], x2, y2, x0, y0);
context.moveTo(p0[0], p0[1]);
context.arcTo(x1, y1, p1[0], p1[1], r);
context.arcTo(x2, y2, p2[0], p2[1], r);
context.arcTo(x0, y0, p0[0], p0[1], r);
context.closePath();
}
}
function closestPoint(x2, y2, x0, y0, x1, y1) {
var x10 = x1 - x0, y10 = y1 - y0,
x20 = x2 - x0, y20 = y2 - y0,
t = (x20 * x10 + y20 * y10) / (x10 * x10 + y10 * y10);
return [x0 + t * x10, y0 + t * y10];
}
function inscribeTriangle(x0, y0, x1, y1, x2, y2) {
var x01 = x0 - x1, y01 = y0 - y1,
x02 = x0 - x2, y02 = y0 - y2,
x12 = x1 - x2, y12 = y1 - y2,
l01 = Math.sqrt(x01 * x01 + y01 * y01),
l02 = Math.sqrt(x02 * x02 + y02 * y02),
l12 = Math.sqrt(x12 * x12 + y12 * y12),
k0 = l01 / (l01 + l02),
k1 = l12 / (l12 + l01),
center = segmentIntersection(x0, y0, x1 - k0 * x12, y1 - k0 * y12, x1, y1, x2 + k1 * x02, y2 + k1 * y02);
center.radius = Math.sqrt((l02 + l12 - l01) * (l12 + l01 - l02) * (l01 + l02 - l12) / (l01 + l02 + l12)) / 2;
return center;
}
function segmentIntersection(x0, y0, x1, y1, x2, y2, x3, y3) {
var x02 = x0 - x2, y02 = y0 - y2,
x10 = x1 - x0, y10 = y1 - y0,
x32 = x3 - x2, y32 = y3 - y2,
t = (x32 * y02 - y32 * x02) / (y32 * x10 - x32 * y10);
return [x0 + t * x10, y0 + t * y10];
}
</script>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment