force-directed distribution

<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <script src="https://d3js.org/d3.v4.min.js"></script>
  <style>
    body { margin:0;position:fixed;top:0;right:0;bottom:0;left:0; background-color:black; }
    svg { background-color: black;}
  </style>
</head>

<body>
  <script>
    const width = 1000
    const height = 500
    const svg = d3.select("body").append("svg")
      .attr("width", width)
      .attr("height", height)
    	.append('g')
    	.attr('transform', 'translate()')

const colorScale = d3.scaleOrdinal()
      .range(['#FCFCFC', 'coral', '#FFFAE3', '#99E1D9', 'skyblue'])

const radius = 7
    const sampleData = d3.range(600).map(() => ({r: radius,
                                                value: width/2 + d3.randomNormal(0,2.8)() * 50}))

// define force
    let force = d3.forceSimulation()
      .force('collision', d3.forceCollide(d => d.r+1).strength(1))
      .force('x', d3.forceX(d => d.value).strength(3))
      .force('y', d3.forceY(height - radius).strength(0.05))
      .nodes(sampleData)
      .on('tick', changeNetwork)

svg.selectAll('circle')
      .data(sampleData)
      .enter()
      .append('circle')
      .style('fill', (d,i) => colorScale(i))
      .attr('r', d => d.r)
      .attr('stroke', 'white')
      .attr('stroke-width', .1)

function changeNetwork() {
      d3.selectAll('circle')
        .attr('cx', d => d.x)
        .attr('cy', d => d.y = Math.min(d.y, height - radius - 1))
    }
  </script>
</body>

https://d3js.org/d3.v4.min.js