voronoi/voronoi.js

console.log('hi voronoi');

const canvas = document.getElementById('canvas'),
    canvwidth = canvas.width,
    canvheight = canvas.height,
    ctx = canvas.getContext('2d');
const minDist = 20,
    edgeBounds = 20;

function drawSite(x, y) {
    ctx.save();
    ctx.beginPath();
    ctx.arc(x, y, 2, 0, Math.PI * 2, false);
    ctx.closePath();
    ctx.fillStyle = 'black';
    ctx.fill();
    ctx.restore();
}
function drawLine(x1, y1, x2, y2) {
    ctx.save();
    ctx.beginPath();
    ctx.strokeStyle = 'black';
    ctx.lineWidth = 1;
    ctx.moveTo(x1, y1);
    ctx.lineTo(x2, y2);
    ctx.stroke();
    ctx.restore();
}
function drawLineO(p1, p2) {
    drawLine(p1.x, p1.y, p2.x, p2.y);
}
function distance(p1, p2) {
    return Math.sqrt(Math.pow(p2.x - p1.x, 2) + Math.pow(p2.y - p1.y, 2));
}
function generateSites(n = 10) {
    const sites = [],
        safety = n * 2,
        randMultWidth = canvwidth - (edgeBounds * 2),
        randMultHeight = canvheight - (edgeBounds * 2),
        origin = {x:0, y:0};

    let count = 0;
    while( sites.length < n && count < safety ) {
        count += 1;
        const x = Math.floor(Math.random() * randMultWidth) + edgeBounds,
            y = Math.floor(Math.random() * randMultHeight) + edgeBounds,
            min = sites.reduce(function checkDist(minSoFar, existing) {
                const d = distance(existing, {x, y});
                if( d < minSoFar ) {
                    return d;
                }
                else {
                    return minSoFar;
                }
            }, canvwidth * canvheight);
        if( min > minDist ) {
            sites.push( {x, y} );
        }
    }

    sites.sort(function (a, b) {
        return distance(origin, a) - distance(origin, b);
    });

    return sites;
}

const sites = generateSites(15);

sites.forEach(function renderSites(site) {
    drawSite(site.x, site.y);
});