Function tree

docs/app/js/sanddance-app.js:138284–138305

(root)

exports.default = function() {
    var separation = defaultSeparation, dx = 1, dy = 1, nodeSize = null;
    function tree(root) {
        var t = treeRoot(root);
        // Compute the layout using Buchheim et al.’s algorithm.
        t.eachAfter(firstWalk), t.parent.m = -t.z;
        t.eachBefore(secondWalk);
        // If a fixed node size is specified, scale x and y.
        if (nodeSize) root.eachBefore(sizeNode);
        else {
            var left = root, right = root, bottom = root;
            root.eachBefore(function(node) {
                if (node.x < left.x) left = node;
                if (node.x > right.x) right = node;
                if (node.depth > bottom.depth) bottom = node;
            });
            var s = left === right ? 1 : separation(left, right) / 2, tx = s - left.x, kx = dx / (right.x + s + tx), ky = dy / (bottom.depth || 1);
            root.eachBefore(function(node) {
                node.x = (node.x + tx) * kx;
                node.y = node.depth * ky;
            });
        }
        return root;
    }
    // Computes a preliminary x-coordinate for v. Before that, FIRST WALK is
    // applied recursively to the children of v, as well as the function
    // APPORTION. After spacing out the children by calling EXECUTE SHIFTS, the