random small curves (grids)

<!DOCTYPE html>
<meta charset="utf-8">
<style>
  rect, path {
    fill: none;
    stroke: black;
    stroke-width: 1;
  }
</style>
<body>
<script src="https://d3js.org/d3.v4.js"></script>
<script src="https://romsson.github.io/d3-gridding/build/d3-gridding.js"></script>
<script>

var width = 400,
    height = 400,
    n = 9,
    data =  d3.range(n),
    max_depth = 4,
    root_grid = 49,
    node_grid = 3;

var svg = d3.select("body")
    .append("svg")
        .attr("width", width)
        .attr("height", height)

var root_params = {
  "size": [width, height],
  "offset": [0, 0],
  "mode": "grid"
};

var level = 0;
  
var line = d3.line().curve(d3.curveBasis);

line
	.x(function(d) { return d.cx; })
  .y(function(d) { return d.cy; });
  
function generate_layout(params, data = d3.range(root_grid), depth = 0) {

var gridding = d3.gridding()
    .params(params);

var griddingData = gridding(data);

if(depth === 3) {
    
    level++;

var lines = svg.selectAll(".line_" + level)
    .data([griddingData]);

lines.enter().insert("path")
      .attr("class", "line_" + level)
      .attr("d", function(d) { return line(d); });
    
  }
  
  if(depth < max_depth) {

griddingData.forEach(function(d, i) {

var grid_type = (i % 2) === 0 ? "coordinate": "horizontal";

var node_params = {
        "size": [d.width, d.height],
        "offset": [d.x, d.y],
        "mode": "coordinate"
      };

if(depth === 2) {
        node_params.size = [node_params.size[0] * 5, node_params.size[1] * 5];
        node_params.offset = [node_params.offset[0] - node_params.size[0], node_params.offset[1] - node_params.size[1]];
      }
      
      generate_layout(node_params, d3.range(node_grid), depth + 1);
    });
  }
}

generate_layout(root_params);

</script>
</body>

Modified http://d3js.org/d3.v4.js to a secure url

Modified http://romsson.github.io/d3-gridding/build/d3-gridding.js to a secure url

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

https://romsson.github.io/d3-gridding/build/d3-gridding.js