code: function getBinaryMapWithDepth(depth) {
    var mm = new mindmaps.MindMap();
    var root = mm.root;
  
    function createTwoChildren(node, depth) {
      if (depth === 0) {
        return;
      }
  
      var left = mm.createNode();
      left.text.caption = "Node " + left.id;
      node.addChild(left);
      createTwoChildren(left, depth - 1);
  
      var right = mm.createNode();
      right.text.caption = "Node " + right.id;
      node.addChild(right);
      createTwoChildren(right, depth - 1);
    }
  
    // depth 10: about 400kb, 800kb in chrome
    // depth 12: about 1600kb
    // depth 16: 25mb
    var depth = depth || 10;
    createTwoChildren(root, depth);
  
    // generate positions for all nodes.
    // tree grows balanced from left to right
    root.offset = new mindmaps.Point(400, 400);
    // var offset = Math.pow(2, depth-1) * 10;
    var offset = 80;
    var c = root.children.values();
    setOffset(c[0], 0, -offset);
    setOffset(c[1], 0, offset);
    function setOffset(node, depth, offsetY) {
      node.offset = new mindmaps.Point((depth + 1) * 50, offsetY);
  
      if (node.isLeaf()) {
        return;
      }
  
      var c = node.children.values();
      var left = c[0];
      setOffset(left, depth + 1, offsetY - offsetY / 2);
  
      var right = c[1];
      setOffset(right, depth + 1, offsetY + offsetY / 2);
    }
  
    // color nodes
    c[0].branchColor = mindmaps.Util.randomColor();
    c[0].forEachDescendant(function(node) {
      node.branchColor = mindmaps.Util.randomColor();
    });
    c[1].branchColor = mindmaps.Util.randomColor();
    c[1].forEachDescendant(function(node) {
      node.branchColor = mindmaps.Util.randomColor();
    });
  
    return mm;
  }
docs: test Default documents