+++ /dev/null
-d3.sankey = function() {
- var sankey = {},
- nodeWidth = 24,
- nodePadding = 8,
- size = [1, 1],
- nodes = [],
- links = [];
-
- sankey.nodeWidth = function(_) {
- if (!arguments.length) return nodeWidth;
- nodeWidth = +_;
- return sankey;
- };
-
- sankey.nodePadding = function(_) {
- if (!arguments.length) return nodePadding;
- nodePadding = +_;
- return sankey;
- };
-
- sankey.nodes = function(_) {
- if (!arguments.length) return nodes;
- nodes = _;
- return sankey;
- };
-
- sankey.links = function(_) {
- if (!arguments.length) return links;
- links = _;
- return sankey;
- };
-
- sankey.size = function(_) {
- if (!arguments.length) return size;
- size = _;
- return sankey;
- };
-
- sankey.layout = function(iterations) {
- computeNodeLinks();
- computeNodeValues();
- computeNodeBreadths();
- computeNodeDepths(iterations);
- computeLinkDepths();
- return sankey;
- };
-
- sankey.relayout = function() {
- computeLinkDepths();
- return sankey;
- };
-
- sankey.link = function() {
- var curvature = .5;
-
- function link(d) {
- var x0 = d.source.x + d.source.dx,
- x1 = d.target.x,
- xi = d3.interpolateNumber(x0, x1),
- x2 = xi(curvature),
- x3 = xi(1 - curvature),
- y0 = d.source.y + d.sy + d.dy / 2,
- y1 = d.target.y + d.ty + d.dy / 2;
- return "M" + x0 + "," + y0
- + "C" + x2 + "," + y0
- + " " + x3 + "," + y1
- + " " + x1 + "," + y1;
- }
-
- link.curvature = function(_) {
- if (!arguments.length) return curvature;
- curvature = +_;
- return link;
- };
-
- return link;
- };
-
- // Populate the sourceLinks and targetLinks for each node.
- // Also, if the source and target are not objects, assume they are indices.
- function computeNodeLinks() {
- nodes.forEach(function(node) {
- node.sourceLinks = [];
- node.targetLinks = [];
- });
- links.forEach(function(link) {
- var source = link.source,
- target = link.target;
- if (typeof source === "number") source = link.source = nodes[link.source];
- if (typeof target === "number") target = link.target = nodes[link.target];
- source.sourceLinks.push(link);
- target.targetLinks.push(link);
- });
- }
-
- // Compute the value (size) of each node by summing the associated links.
- function computeNodeValues() {
- nodes.forEach(function(node) {
- node.value = Math.max(
- d3.sum(node.sourceLinks, value),
- d3.sum(node.targetLinks, value)
- );
- });
- }
-
- // Iteratively assign the breadth (x-position) for each node.
- // Nodes are assigned the maximum breadth of incoming neighbors plus one;
- // nodes with no incoming links are assigned breadth zero, while
- // nodes with no outgoing links are assigned the maximum breadth.
- function computeNodeBreadths() {
- var remainingNodes = nodes,
- nextNodes,
- x = 0;
-
- while (remainingNodes.length) {
- nextNodes = [];
- remainingNodes.forEach(function(node) {
- node.x = x;
- node.dx = nodeWidth;
- node.sourceLinks.forEach(function(link) {
- nextNodes.push(link.target);
- });
- });
- remainingNodes = nextNodes;
- ++x;
- }
-
- //
- moveSinksRight(x);
- scaleNodeBreadths((size[0] - nodeWidth) / (x - 1));
- }
-
- function moveSourcesRight() {
- nodes.forEach(function(node) {
- if (!node.targetLinks.length) {
- node.x = d3.min(node.sourceLinks, function(d) { return d.target.x; }) - 1;
- }
- });
- }
-
- function moveSinksRight(x) {
- nodes.forEach(function(node) {
- if (!node.sourceLinks.length) {
- node.x = x - 1;
- }
- });
- }
-
- function scaleNodeBreadths(kx) {
- nodes.forEach(function(node) {
- node.x *= kx;
- });
- }
-
- function computeNodeDepths(iterations) {
- var nodesByBreadth = d3.nest()
- .key(function(d) { return d.x; })
- .sortKeys(d3.ascending)
- .entries(nodes)
- .map(function(d) { return d.values; });
-
- //
- initializeNodeDepth();
- resolveCollisions();
- for (var alpha = 1; iterations > 0; --iterations) {
- relaxRightToLeft(alpha *= .99);
- resolveCollisions();
- relaxLeftToRight(alpha);
- resolveCollisions();
- }
-
- function initializeNodeDepth() {
- var ky = d3.min(nodesByBreadth, function(nodes) {
- return (size[1] - (nodes.length - 1) * nodePadding) / d3.sum(nodes, value);
- });
-
- nodesByBreadth.forEach(function(nodes) {
- nodes.forEach(function(node, i) {
- node.y = i;
- node.dy = node.value * ky;
- });
- });
-
- links.forEach(function(link) {
- link.dy = link.value * ky;
- });
- }
-
- function relaxLeftToRight(alpha) {
- nodesByBreadth.forEach(function(nodes, breadth) {
- nodes.forEach(function(node) {
- if (node.targetLinks.length) {
- var y = d3.sum(node.targetLinks, weightedSource) / d3.sum(node.targetLinks, value);
- node.y += (y - center(node)) * alpha;
- }
- });
- });
-
- function weightedSource(link) {
- return center(link.source) * link.value;
- }
- }
-
- function relaxRightToLeft(alpha) {
- nodesByBreadth.slice().reverse().forEach(function(nodes) {
- nodes.forEach(function(node) {
- if (node.sourceLinks.length) {
- var y = d3.sum(node.sourceLinks, weightedTarget) / d3.sum(node.sourceLinks, value);
- node.y += (y - center(node)) * alpha;
- }
- });
- });
-
- function weightedTarget(link) {
- return center(link.target) * link.value;
- }
- }
-
- function resolveCollisions() {
- nodesByBreadth.forEach(function(nodes) {
- var node,
- dy,
- y0 = 0,
- n = nodes.length,
- i;
-
- // Push any overlapping nodes down.
- nodes.sort(ascendingDepth);
- for (i = 0; i < n; ++i) {
- node = nodes[i];
- dy = y0 - node.y;
- if (dy > 0) node.y += dy;
- y0 = node.y + node.dy + nodePadding;
- }
-
- // If the bottommost node goes outside the bounds, push it back up.
- dy = y0 - nodePadding - size[1];
- if (dy > 0) {
- y0 = node.y -= dy;
-
- // Push any overlapping nodes back up.
- for (i = n - 2; i >= 0; --i) {
- node = nodes[i];
- dy = node.y + node.dy + nodePadding - y0;
- if (dy > 0) node.y -= dy;
- y0 = node.y;
- }
- }
- });
- }
-
- function ascendingDepth(a, b) {
- return a.y - b.y;
- }
- }
-
- function computeLinkDepths() {
- nodes.forEach(function(node) {
- node.sourceLinks.sort(ascendingTargetDepth);
- node.targetLinks.sort(ascendingSourceDepth);
- });
- nodes.forEach(function(node) {
- var sy = 0, ty = 0;
- node.sourceLinks.forEach(function(link) {
- link.sy = sy;
- sy += link.dy;
- });
- node.targetLinks.forEach(function(link) {
- link.ty = ty;
- ty += link.dy;
- });
- });
-
- function ascendingSourceDepth(a, b) {
- return a.source.y - b.source.y;
- }
-
- function ascendingTargetDepth(a, b) {
- return a.target.y - b.target.y;
- }
- }
-
- function center(node) {
- return node.y + node.dy / 2;
- }
-
- function value(link) {
- return link.value;
- }
-
- return sankey;
-};
Code Review / policy / engine.git / blobdiff