'use strict'; /** * There's a mix-up with terms in the code. Following are the formal definitions: * * tree - a strict hierarchical network, i.e. every node has at most one parent * forest - a collection of trees. These distinct trees are thus not connected. * * So: * - in a network that is not a tree, there exist nodes with multiple parents. * - a network consisting of unconnected sub-networks, of which at least one * is not a tree, is not a forest. * * In the code, the definitions are: * * tree - any disconnected sub-network, strict hierarchical or not. * forest - a bunch of these sub-networks * * The difference between tree and not-tree is important in the code, notably within * to the block-shifting algorithm. The algorithm assumes formal trees and fails * for not-trees, often in a spectacular manner (search for 'exploding network' in the issues). * * In order to distinguish the definitions in the following code, the adjective 'formal' is * used. If 'formal' is absent, you must assume the non-formal definition. * * ---------------------------------------------------------------------------------- * NOTES * ===== * * A hierarchical layout is a different thing from a hierarchical network. * The layout is a way to arrange the nodes in the view; this can be done * on non-hierarchical networks as well. The converse is also possible. */ let util = require('../../util'); var NetworkUtil = require('../NetworkUtil').default; /** * Container for derived data on current network, relating to hierarchy. * * @class HierarchicalStatus * @private */ class HierarchicalStatus { /** * @constructor HierarchicalStatus */ constructor() { this.childrenReference = {}; // child id's per node id this.parentReference = {}; // parent id's per node id this.trees = {}; // tree id per node id; i.e. to which tree does given node id belong this.distributionOrdering = {}; // The nodes per level, in the display order this.levels = {}; // hierarchy level per node id this.distributionIndex = {}; // The position of the node in the level sorting order, per node id. this.isTree = false; // True if current network is a formal tree this.treeIndex = -1; // Highest tree id in current network. } /** * Add the relation between given nodes to the current state. * * @param {vis.Node.id} parentNodeId * @param {vis.Node.id} childNodeId */ addRelation(parentNodeId, childNodeId) { if (this.childrenReference[parentNodeId] === undefined) { this.childrenReference[parentNodeId] = []; } this.childrenReference[parentNodeId].push(childNodeId); if (this.parentReference[childNodeId] === undefined) { this.parentReference[childNodeId] = []; } this.parentReference[childNodeId].push(parentNodeId); } /** * Check if the current state is for a formal tree or formal forest. * * This is the case if every node has at most one parent. * * Pre: parentReference init'ed properly for current network */ checkIfTree() { for (let i in this.parentReference) { if (this.parentReference[i].length > 1) { this.isTree = false; return; } } this.isTree = true; } /** * Return the number of separate trees in the current network. * @returns {Number} */ numTrees() { return (this.treeIndex + 1); // This assumes the indexes are assigned consecitively } /** * Assign a tree id to a node * @param {vis.Node} node * @param {String|Number} treeId */ setTreeIndex(node, treeId) { if (this.trees[node.id] === undefined) { this.trees[node.id] = treeId; this.treeIndex = Math.max(treeId, this.treeIndex); } } /** * Ensure level for given id is defined. * * Sets level to zero for given node id if not already present * * @param {vis.Node.id} nodeId */ ensureLevel(nodeId) { if (this.levels[nodeId] === undefined) { this.levels[nodeId] = 0; } } /** * get the maximum level of a branch. * * TODO: Never entered; find a test case to test this! * @param {vis.Node.id} nodeId * @returns {Number} */ getMaxLevel(nodeId) { let accumulator = {}; let _getMaxLevel = (nodeId) => { if (accumulator[nodeId] !== undefined) { return accumulator[nodeId]; } let level = this.levels[nodeId]; if (this.childrenReference[nodeId]) { let children = this.childrenReference[nodeId]; if (children.length > 0) { for (let i = 0; i < children.length; i++) { level = Math.max(level,_getMaxLevel(children[i])); } } } accumulator[nodeId] = level; return level; }; return _getMaxLevel(nodeId); } /** * * @param {Node} nodeA * @param {Node} nodeB */ levelDownstream(nodeA, nodeB) { if (this.levels[nodeB.id] === undefined) { // set initial level if (this.levels[nodeA.id] === undefined) { this.levels[nodeA.id] = 0; } // set level this.levels[nodeB.id] = this.levels[nodeA.id] + 1; } } /** * Small util method to set the minimum levels of the nodes to zero. * * @param {Array} nodes */ setMinLevelToZero(nodes) { let minLevel = 1e9; // get the minimum level for (let nodeId in nodes) { if (nodes.hasOwnProperty(nodeId)) { if (this.levels[nodeId] !== undefined) { minLevel = Math.min(this.levels[nodeId], minLevel); } } } // subtract the minimum from the set so we have a range starting from 0 for (let nodeId in nodes) { if (nodes.hasOwnProperty(nodeId)) { if (this.levels[nodeId] !== undefined) { this.levels[nodeId] -= minLevel; } } } } /** * Get the min and max xy-coordinates of a given tree * * @param {Array} nodes * @param {Number} index * @returns {{min_x: number, max_x: number, min_y: number, max_y: number}} */ getTreeSize(nodes, index) { let min_x = 1e9; let max_x = -1e9; let min_y = 1e9; let max_y = -1e9; for (let nodeId in this.trees) { if (this.trees.hasOwnProperty(nodeId)) { if (this.trees[nodeId] === index) { let node = nodes[nodeId]; min_x = Math.min(node.x, min_x); max_x = Math.max(node.x, max_x); min_y = Math.min(node.y, min_y); max_y = Math.max(node.y, max_y); } } } return { min_x: min_x, max_x: max_x, min_y: min_y, max_y: max_y }; } /** * Check if two nodes have the same parent(s) * * @param {vis.Node} node1 * @param {vis.Node} node2 * @return {boolean} true if the two nodes have a same ancestor node, false otherwise */ hasSameParent(node1, node2) { let parents1 = this.parentReference[node1.id]; let parents2 = this.parentReference[node2.id]; if (parents1 === undefined || parents2 === undefined) { return false; } for (let i = 0; i < parents1.length; i++) { for (let j = 0; j < parents2.length; j++) { if (parents1[i] == parents2[j]) { return true; } } } return false; } /** * Check if two nodes are in the same tree. * * @param {vis.Node} node1 * @param {vis.Node} node2 * @return {Boolean} true if this is so, false otherwise */ inSameSubNetwork(node1, node2) { return (this.trees[node1.id] === this.trees[node2.id]); } /** * Get a list of the distinct levels in the current network * * @returns {Array} */ getLevels() { return Object.keys(this.distributionOrdering); } /** * Add a node to the ordering per level * * @param {vis.Node} node * @param {Number} level */ addToOrdering(node, level) { if (this.distributionOrdering[level] === undefined) { this.distributionOrdering[level] = []; } var isPresent = false; var curLevel = this.distributionOrdering[level]; for (var n in curLevel) { //if (curLevel[n].id === node.id) { if (curLevel[n] === node) { isPresent = true; break; } } if (!isPresent) { this.distributionOrdering[level].push(node); this.distributionIndex[node.id] = this.distributionOrdering[level].length - 1; } } } /** * @class LayoutEngine */ class LayoutEngine { /** * @param {Object} body * @constructor LayoutEngine */ constructor(body) { this.body = body; this.initialRandomSeed = Math.round(Math.random() * 1000000); this.randomSeed = this.initialRandomSeed; this.setPhysics = false; this.options = {}; this.optionsBackup = {physics:{}}; this.defaultOptions = { randomSeed: undefined, improvedLayout: true, hierarchical: { enabled:false, levelSeparation: 150, nodeSpacing: 100, treeSpacing: 200, blockShifting: true, edgeMinimization: true, parentCentralization: true, direction: 'UD', // UD, DU, LR, RL sortMethod: 'hubsize' // hubsize, directed } }; util.extend(this.options, this.defaultOptions); this.bindEventListeners(); } /** * Binds event listeners */ bindEventListeners() { this.body.emitter.on('_dataChanged', () => { this.setupHierarchicalLayout(); }); this.body.emitter.on('_dataLoaded', () => { this.layoutNetwork(); }); this.body.emitter.on('_resetHierarchicalLayout', () => { this.setupHierarchicalLayout(); }); this.body.emitter.on('_adjustEdgesForHierarchicalLayout', () => { if (this.options.hierarchical.enabled !== true) { return; } // get the type of static smooth curve in case it is required let type = this.getStaticType(); // force all edges into static smooth curves. this.body.emitter.emit('_forceDisableDynamicCurves', type, false); }); } /** * * @param {Object} options * @param {Object} allOptions * @returns {Object} */ setOptions(options, allOptions) { if (options !== undefined) { let hierarchical = this.options.hierarchical; let prevHierarchicalState = hierarchical.enabled; util.selectiveDeepExtend(["randomSeed", "improvedLayout"],this.options, options); util.mergeOptions(this.options, options, 'hierarchical'); if (options.randomSeed !== undefined) {this.initialRandomSeed = options.randomSeed;} if (hierarchical.enabled === true) { if (prevHierarchicalState === true) { // refresh the overridden options for nodes and edges. this.body.emitter.emit('refresh', true); } // make sure the level separation is the right way up if (hierarchical.direction === 'RL' || hierarchical.direction === 'DU') { if (hierarchical.levelSeparation > 0) { hierarchical.levelSeparation *= -1; } } else { if (hierarchical.levelSeparation < 0) { hierarchical.levelSeparation *= -1; } } this.body.emitter.emit('_resetHierarchicalLayout'); // because the hierarchical system needs it's own physics and smooth curve settings, // we adapt the other options if needed. return this.adaptAllOptionsForHierarchicalLayout(allOptions); } else { if (prevHierarchicalState === true) { // refresh the overridden options for nodes and edges. this.body.emitter.emit('refresh'); return util.deepExtend(allOptions,this.optionsBackup); } } } return allOptions; } /** * * @param {Object} allOptions * @returns {Object} */ adaptAllOptionsForHierarchicalLayout(allOptions) { if (this.options.hierarchical.enabled === true) { let backupPhysics = this.optionsBackup.physics; // set the physics if (allOptions.physics === undefined || allOptions.physics === true) { allOptions.physics = { enabled: backupPhysics.enabled === undefined ? true : backupPhysics.enabled, solver :'hierarchicalRepulsion' }; backupPhysics.enabled = backupPhysics.enabled === undefined ? true : backupPhysics.enabled; backupPhysics.solver = backupPhysics.solver || 'barnesHut'; } else if (typeof allOptions.physics === 'object') { backupPhysics.enabled = allOptions.physics.enabled === undefined ? true : allOptions.physics.enabled; backupPhysics.solver = allOptions.physics.solver || 'barnesHut'; allOptions.physics.solver = 'hierarchicalRepulsion'; } else if (allOptions.physics !== false) { backupPhysics.solver ='barnesHut'; allOptions.physics = {solver:'hierarchicalRepulsion'}; } // get the type of static smooth curve in case it is required let type = this.getStaticType(); // disable smooth curves if nothing is defined. If smooth curves have been turned on, // turn them into static smooth curves. if (allOptions.edges === undefined) { this.optionsBackup.edges = {smooth:{enabled:true, type:'dynamic'}}; allOptions.edges = {smooth: false}; } else if (allOptions.edges.smooth === undefined) { this.optionsBackup.edges = {smooth:{enabled:true, type:'dynamic'}}; allOptions.edges.smooth = false; } else { if (typeof allOptions.edges.smooth === 'boolean') { this.optionsBackup.edges = {smooth:allOptions.edges.smooth}; allOptions.edges.smooth = {enabled: allOptions.edges.smooth, type:type} } else { let smooth = allOptions.edges.smooth; // allow custom types except for dynamic if (smooth.type !== undefined && smooth.type !== 'dynamic') { type = smooth.type; } // TODO: this is options merging; see if the standard routines can be used here. this.optionsBackup.edges = { smooth : smooth.enabled === undefined ? true : smooth.enabled, type : smooth.type === undefined ? 'dynamic': smooth.type, roundness : smooth.roundness === undefined ? 0.5 : smooth.roundness, forceDirection: smooth.forceDirection === undefined ? false : smooth.forceDirection }; // NOTE: Copying an object to self; this is basically setting defaults for undefined variables allOptions.edges.smooth = { enabled : smooth.enabled === undefined ? true : smooth.enabled, type : type, roundness : smooth.roundness === undefined ? 0.5 : smooth.roundness, forceDirection: smooth.forceDirection === undefined ? false: smooth.forceDirection } } } // Force all edges into static smooth curves. // Only applies to edges that do not use the global options for smooth. this.body.emitter.emit('_forceDisableDynamicCurves', type); } return allOptions; } /** * * @returns {number} */ seededRandom() { let x = Math.sin(this.randomSeed++) * 10000; return x - Math.floor(x); } /** * * @param {Array} nodesArray */ positionInitially(nodesArray) { if (this.options.hierarchical.enabled !== true) { this.randomSeed = this.initialRandomSeed; let radius = nodesArray.length + 50; for (let i = 0; i < nodesArray.length; i++) { let node = nodesArray[i]; let angle = 2 * Math.PI * this.seededRandom(); if (node.x === undefined) { node.x = radius * Math.cos(angle); } if (node.y === undefined) { node.y = radius * Math.sin(angle); } } } } /** * Use Kamada Kawai to position nodes. This is quite a heavy algorithm so if there are a lot of nodes we * cluster them first to reduce the amount. */ layoutNetwork() { if (this.options.hierarchical.enabled !== true && this.options.improvedLayout === true) { let indices = this.body.nodeIndices; // first check if we should Kamada Kawai to layout. The threshold is if less than half of the visible // nodes have predefined positions we use this. let positionDefined = 0; for (let i = 0; i < indices.length; i++) { let node = this.body.nodes[indices[i]]; if (node.predefinedPosition === true) { positionDefined += 1; } } // if less than half of the nodes have a predefined position we continue if (positionDefined < 0.5 * indices.length) { let MAX_LEVELS = 10; let level = 0; let clusterThreshold = 150; // Performance enhancement, during clustering edges need only be simple straight lines. // These options don't propagate outside the clustering phase. let clusterOptions = { clusterEdgeProperties:{ smooth: { enabled: false } } }; // if there are a lot of nodes, we cluster before we run the algorithm. // NOTE: this part fails to find clusters for large scale-free networks, which should // be easily clusterable. // TODO: examine why this is so if (indices.length > clusterThreshold) { let startLength = indices.length; while (indices.length > clusterThreshold && level <= MAX_LEVELS) { //console.time("clustering") level += 1; let before = indices.length; // if there are many nodes we do a hubsize cluster if (level % 3 === 0) { this.body.modules.clustering.clusterBridges(clusterOptions); } else { this.body.modules.clustering.clusterOutliers(clusterOptions); } let after = indices.length; if (before == after && level % 3 !== 0) { this._declusterAll(); this.body.emitter.emit("_layoutFailed"); console.info("This network could not be positioned by this version of the improved layout algorithm." + " Please disable improvedLayout for better performance."); return; } //console.timeEnd("clustering") //console.log(before,level,after); } // increase the size of the edges this.body.modules.kamadaKawai.setOptions({springLength: Math.max(150, 2 * startLength)}) } if (level > MAX_LEVELS){ console.info("The clustering didn't succeed within the amount of interations allowed," + " progressing with partial result."); } // position the system for these nodes and edges this.body.modules.kamadaKawai.solve(indices, this.body.edgeIndices, true); // shift to center point this._shiftToCenter(); // perturb the nodes a little bit to force the physics to kick in let offset = 70; for (let i = 0; i < indices.length; i++) { // Only perturb the nodes that aren't fixed let node = this.body.nodes[indices[i]]; if (node.predefinedPosition === false) { node.x += (0.5 - this.seededRandom())*offset; node.y += (0.5 - this.seededRandom())*offset; } } // uncluster all clusters this._declusterAll(); // reposition all bezier nodes. this.body.emitter.emit("_repositionBezierNodes"); } } } /** * Move all the nodes towards to the center so gravitational pull wil not move the nodes away from view * @private */ _shiftToCenter() { let range = NetworkUtil.getRangeCore(this.body.nodes, this.body.nodeIndices); let center = NetworkUtil.findCenter(range); for (let i = 0; i < this.body.nodeIndices.length; i++) { let node = this.body.nodes[this.body.nodeIndices[i]]; node.x -= center.x; node.y -= center.y; } } /** * Expands all clusters * @private */ _declusterAll() { let clustersPresent = true; while (clustersPresent === true) { clustersPresent = false; for (let i = 0; i < this.body.nodeIndices.length; i++) { if (this.body.nodes[this.body.nodeIndices[i]].isCluster === true) { clustersPresent = true; this.body.modules.clustering.openCluster(this.body.nodeIndices[i], {}, false); } } if (clustersPresent === true) { this.body.emitter.emit('_dataChanged'); } } } /** * * @returns {number|*} */ getSeed() { return this.initialRandomSeed; } /** * This is the main function to layout the nodes in a hierarchical way. * It checks if the node details are supplied correctly * * @private */ setupHierarchicalLayout() { if (this.options.hierarchical.enabled === true && this.body.nodeIndices.length > 0) { // get the size of the largest hubs and check if the user has defined a level for a node. let node, nodeId; let definedLevel = false; let undefinedLevel = false; this.lastNodeOnLevel = {}; this.hierarchical = new HierarchicalStatus(); for (nodeId in this.body.nodes) { if (this.body.nodes.hasOwnProperty(nodeId)) { node = this.body.nodes[nodeId]; if (node.options.level !== undefined) { definedLevel = true; this.hierarchical.levels[nodeId] = node.options.level; } else { undefinedLevel = true; } } } // if the user defined some levels but not all, alert and run without hierarchical layout if (undefinedLevel === true && definedLevel === true) { throw new Error('To use the hierarchical layout, nodes require either no predefined levels' + ' or levels have to be defined for all nodes.'); } else { // define levels if undefined by the users. Based on hubsize. if (undefinedLevel === true) { let sortMethod = this.options.hierarchical.sortMethod; if (sortMethod === 'hubsize') { this._determineLevelsByHubsize(); } else if (sortMethod === 'directed') { this._determineLevelsDirected(); } else if (sortMethod === 'custom') { this._determineLevelsCustomCallback(); } } // fallback for cases where there are nodes but no edges for (let nodeId in this.body.nodes) { if (this.body.nodes.hasOwnProperty(nodeId)) { this.hierarchical.ensureLevel(nodeId); } } // check the distribution of the nodes per level. let distribution = this._getDistribution(); // get the parent children relations. this._generateMap(); // place the nodes on the canvas. this._placeNodesByHierarchy(distribution); // condense the whitespace. this._condenseHierarchy(); // shift to center so gravity does not have to do much this._shiftToCenter(); } } } /** * @private */ _condenseHierarchy() { // Global var in this scope to define when the movement has stopped. let stillShifting = false; let branches = {}; // first we have some methods to help shifting trees around. // the main method to shift the trees let shiftTrees = () => { let treeSizes = getTreeSizes(); let shiftBy = 0; for (let i = 0; i < treeSizes.length - 1; i++) { let diff = treeSizes[i].max - treeSizes[i+1].min; shiftBy += diff + this.options.hierarchical.treeSpacing; shiftTree(i + 1, shiftBy); } }; // shift a single tree by an offset let shiftTree = (index, offset) => { let trees = this.hierarchical.trees; for (let nodeId in trees) { if (trees.hasOwnProperty(nodeId)) { if (trees[nodeId] === index) { let node = this.body.nodes[nodeId]; let pos = this._getPositionForHierarchy(node); this._setPositionForHierarchy(node, pos + offset, undefined, true); } } } }; // get the width of a tree let getTreeSize = (index) => { let res = this.hierarchical.getTreeSize(this.body.nodes, index); if (this._isVertical()) { return {min: res.min_x, max: res.max_x}; } else { return {min: res.min_y, max: res.max_y}; } }; // get the width of all trees let getTreeSizes = () => { let treeWidths = []; for (let i = 0; i <= this.hierarchical.numTrees(); i++) { treeWidths.push(getTreeSize(i)); } return treeWidths; }; // get a map of all nodes in this branch let getBranchNodes = (source, map) => { if (map[source.id]) { return; } map[source.id] = true; if (this.hierarchical.childrenReference[source.id]) { let children = this.hierarchical.childrenReference[source.id]; if (children.length > 0) { for (let i = 0; i < children.length; i++) { getBranchNodes(this.body.nodes[children[i]], map); } } } }; // get a min max width as well as the maximum movement space it has on either sides // we use min max terminology because width and height can interchange depending on the direction of the layout let getBranchBoundary = (branchMap, maxLevel = 1e9) => { let minSpace = 1e9; let maxSpace = 1e9; let min = 1e9; let max = -1e9; for (let branchNode in branchMap) { if (branchMap.hasOwnProperty(branchNode)) { let node = this.body.nodes[branchNode]; let level = this.hierarchical.levels[node.id]; let position = this._getPositionForHierarchy(node); // get the space around the node. let [minSpaceNode, maxSpaceNode] = this._getSpaceAroundNode(node,branchMap); minSpace = Math.min(minSpaceNode, minSpace); maxSpace = Math.min(maxSpaceNode, maxSpace); // the width is only relevant for the levels two nodes have in common. This is why we filter on this. if (level <= maxLevel) { min = Math.min(position, min); max = Math.max(position, max); } } } return [min, max, minSpace, maxSpace]; } // check what the maximum level is these nodes have in common. let getCollisionLevel = (node1, node2) => { let maxLevel1 = this.hierarchical.getMaxLevel(node1.id); let maxLevel2 = this.hierarchical.getMaxLevel(node2.id); return Math.min(maxLevel1, maxLevel2); }; /** * Condense elements. These can be nodes or branches depending on the callback. * * @param {function} callback * @param {Array} levels * @param {*} centerParents */ let shiftElementsCloser = (callback, levels, centerParents) => { let hier = this.hierarchical; for (let i = 0; i < levels.length; i++) { let level = levels[i]; let levelNodes = hier.distributionOrdering[level]; if (levelNodes.length > 1) { for (let j = 0; j < levelNodes.length - 1; j++) { let node1 = levelNodes[j]; let node2 = levelNodes[j+1]; // NOTE: logic maintained as it was; if nodes have same ancestor, // then of course they are in the same sub-network. if (hier.hasSameParent(node1, node2) && hier.inSameSubNetwork(node1, node2) ) { callback(node1, node2, centerParents); } } } } }; // callback for shifting branches let branchShiftCallback = (node1, node2, centerParent = false) => { //window.CALLBACKS.push(() => { let pos1 = this._getPositionForHierarchy(node1); let pos2 = this._getPositionForHierarchy(node2); let diffAbs = Math.abs(pos2 - pos1); let nodeSpacing = this.options.hierarchical.nodeSpacing; //console.log("NOW CHECKING:", node1.id, node2.id, diffAbs); if (diffAbs > nodeSpacing) { let branchNodes1 = {}; let branchNodes2 = {}; getBranchNodes(node1, branchNodes1); getBranchNodes(node2, branchNodes2); // check the largest distance between the branches let maxLevel = getCollisionLevel(node1, node2); let branchNodeBoundary1 = getBranchBoundary(branchNodes1, maxLevel); let branchNodeBoundary2 = getBranchBoundary(branchNodes2, maxLevel); let max1 = branchNodeBoundary1[1]; let min2 = branchNodeBoundary2[0]; let minSpace2 = branchNodeBoundary2[2]; //console.log(node1.id, getBranchBoundary(branchNodes1, maxLevel), node2.id, // getBranchBoundary(branchNodes2, maxLevel), maxLevel); let diffBranch = Math.abs(max1 - min2); if (diffBranch > nodeSpacing) { let offset = max1 - min2 + nodeSpacing; if (offset < -minSpace2 + nodeSpacing) { offset = -minSpace2 + nodeSpacing; //console.log("RESETTING OFFSET", max1 - min2 + this.options.hierarchical.nodeSpacing, -minSpace2, offset); } if (offset < 0) { //console.log("SHIFTING", node2.id, offset); this._shiftBlock(node2.id, offset); stillShifting = true; if (centerParent === true) this._centerParent(node2); } } } //this.body.emitter.emit("_redraw");}) }; let minimizeEdgeLength = (iterations, node) => { //window.CALLBACKS.push(() => { // console.log("ts",node.id); let nodeId = node.id; let allEdges = node.edges; let nodeLevel = this.hierarchical.levels[node.id]; // gather constants let C2 = this.options.hierarchical.levelSeparation * this.options.hierarchical.levelSeparation; let referenceNodes = {}; let aboveEdges = []; for (let i = 0; i < allEdges.length; i++) { let edge = allEdges[i]; if (edge.toId != edge.fromId) { let otherNode = edge.toId == nodeId ? edge.from : edge.to; referenceNodes[allEdges[i].id] = otherNode; if (this.hierarchical.levels[otherNode.id] < nodeLevel) { aboveEdges.push(edge); } } } // differentiated sum of lengths based on only moving one node over one axis let getFx = (point, edges) => { let sum = 0; for (let i = 0; i < edges.length; i++) { if (referenceNodes[edges[i].id] !== undefined) { let a = this._getPositionForHierarchy(referenceNodes[edges[i].id]) - point; sum += a / Math.sqrt(a * a + C2); } } return sum; }; // doubly differentiated sum of lengths based on only moving one node over one axis let getDFx = (point, edges) => { let sum = 0; for (let i = 0; i < edges.length; i++) { if (referenceNodes[edges[i].id] !== undefined) { let a = this._getPositionForHierarchy(referenceNodes[edges[i].id]) - point; sum -= (C2 * Math.pow(a * a + C2, -1.5)); } } return sum; }; let getGuess = (iterations, edges) => { let guess = this._getPositionForHierarchy(node); // Newton's method for optimization let guessMap = {}; for (let i = 0; i < iterations; i++) { let fx = getFx(guess, edges); let dfx = getDFx(guess, edges); // we limit the movement to avoid instability. let limit = 40; let ratio = Math.max(-limit, Math.min(limit, Math.round(fx/dfx))); guess = guess - ratio; // reduce duplicates if (guessMap[guess] !== undefined) { break; } guessMap[guess] = i; } return guess; }; let moveBranch = (guess) => { // position node if there is space let nodePosition = this._getPositionForHierarchy(node); // check movable area of the branch if (branches[node.id] === undefined) { let branchNodes = {}; getBranchNodes(node, branchNodes); branches[node.id] = branchNodes; } let branchBoundary = getBranchBoundary(branches[node.id]); let minSpaceBranch = branchBoundary[2]; let maxSpaceBranch = branchBoundary[3]; let diff = guess - nodePosition; // check if we are allowed to move the node: let branchOffset = 0; if (diff > 0) { branchOffset = Math.min(diff, maxSpaceBranch - this.options.hierarchical.nodeSpacing); } else if (diff < 0) { branchOffset = -Math.min(-diff, minSpaceBranch - this.options.hierarchical.nodeSpacing); } if (branchOffset != 0) { //console.log("moving branch:",branchOffset, maxSpaceBranch, minSpaceBranch) this._shiftBlock(node.id, branchOffset); //this.body.emitter.emit("_redraw"); stillShifting = true; } }; let moveNode = (guess) => { let nodePosition = this._getPositionForHierarchy(node); // position node if there is space let [minSpace, maxSpace] = this._getSpaceAroundNode(node); let diff = guess - nodePosition; // check if we are allowed to move the node: let newPosition = nodePosition; if (diff > 0) { newPosition = Math.min(nodePosition + (maxSpace - this.options.hierarchical.nodeSpacing), guess); } else if (diff < 0) { newPosition = Math.max(nodePosition - (minSpace - this.options.hierarchical.nodeSpacing), guess); } if (newPosition !== nodePosition) { //console.log("moving Node:",diff, minSpace, maxSpace); this._setPositionForHierarchy(node, newPosition, undefined, true); //this.body.emitter.emit("_redraw"); stillShifting = true; } }; let guess = getGuess(iterations, aboveEdges); moveBranch(guess); guess = getGuess(iterations, allEdges); moveNode(guess); //}) }; // method to remove whitespace between branches. Because we do bottom up, we can center the parents. let minimizeEdgeLengthBottomUp = (iterations) => { let levels = this.hierarchical.getLevels(); levels = levels.reverse(); for (let i = 0; i < iterations; i++) { stillShifting = false; for (let j = 0; j < levels.length; j++) { let level = levels[j]; let levelNodes = this.hierarchical.distributionOrdering[level]; for (let k = 0; k < levelNodes.length; k++) { minimizeEdgeLength(1000, levelNodes[k]); } } if (stillShifting !== true) { //console.log("FINISHED minimizeEdgeLengthBottomUp IN " + i); break; } } }; // method to remove whitespace between branches. Because we do bottom up, we can center the parents. let shiftBranchesCloserBottomUp = (iterations) => { let levels = this.hierarchical.getLevels(); levels = levels.reverse(); for (let i = 0; i < iterations; i++) { stillShifting = false; shiftElementsCloser(branchShiftCallback, levels, true); if (stillShifting !== true) { //console.log("FINISHED shiftBranchesCloserBottomUp IN " + (i+1)); break; } } }; // center all parents let centerAllParents = () => { for (let nodeId in this.body.nodes) { if (this.body.nodes.hasOwnProperty(nodeId)) this._centerParent(this.body.nodes[nodeId]); } }; // center all parents let centerAllParentsBottomUp = () => { let levels = this.hierarchical.getLevels(); levels = levels.reverse(); for (let i = 0; i < levels.length; i++) { let level = levels[i]; let levelNodes = this.hierarchical.distributionOrdering[level]; for (let j = 0; j < levelNodes.length; j++) { this._centerParent(levelNodes[j]); } } }; // the actual work is done here. if (this.options.hierarchical.blockShifting === true) { shiftBranchesCloserBottomUp(5); centerAllParents(); } // minimize edge length if (this.options.hierarchical.edgeMinimization === true) { minimizeEdgeLengthBottomUp(20); } if (this.options.hierarchical.parentCentralization === true) { centerAllParentsBottomUp() } shiftTrees(); } /** * This gives the space around the node. IF a map is supplied, it will only check against nodes NOT in the map. * This is used to only get the distances to nodes outside of a branch. * @param {vis.Node} node * @param {{vis.Node.id: vis.Node}} map * @returns {Number[]} * @private */ _getSpaceAroundNode(node, map) { let useMap = true; if (map === undefined) { useMap = false; } let level = this.hierarchical.levels[node.id]; if (level !== undefined) { let index = this.hierarchical.distributionIndex[node.id]; let position = this._getPositionForHierarchy(node); let ordering = this.hierarchical.distributionOrdering[level]; let minSpace = 1e9; let maxSpace = 1e9; if (index !== 0) { let prevNode = ordering[index - 1]; if ((useMap === true && map[prevNode.id] === undefined) || useMap === false) { let prevPos = this._getPositionForHierarchy(prevNode); minSpace = position - prevPos; } } if (index != ordering.length - 1) { let nextNode = ordering[index + 1]; if ((useMap === true && map[nextNode.id] === undefined) || useMap === false) { let nextPos = this._getPositionForHierarchy(nextNode); maxSpace = Math.min(maxSpace, nextPos - position); } } return [minSpace, maxSpace]; } else { return [0, 0]; } } /** * We use this method to center a parent node and check if it does not cross other nodes when it does. * @param {vis.Node} node * @private */ _centerParent(node) { if (this.hierarchical.parentReference[node.id]) { let parents = this.hierarchical.parentReference[node.id]; for (var i = 0; i < parents.length; i++) { let parentId = parents[i]; let parentNode = this.body.nodes[parentId]; let children = this.hierarchical.childrenReference[parentId]; if (children !== undefined) { // get the range of the children let newPosition = this._getCenterPosition(children); let position = this._getPositionForHierarchy(parentNode); let [minSpace, maxSpace] = this._getSpaceAroundNode(parentNode); let diff = position - newPosition; if ((diff < 0 && Math.abs(diff) < maxSpace - this.options.hierarchical.nodeSpacing) || (diff > 0 && Math.abs(diff) < minSpace - this.options.hierarchical.nodeSpacing)) { this._setPositionForHierarchy(parentNode, newPosition, undefined, true); } } } } } /** * This function places the nodes on the canvas based on the hierarchial distribution. * * @param {Object} distribution | obtained by the function this._getDistribution() * @private */ _placeNodesByHierarchy(distribution) { this.positionedNodes = {}; // start placing all the level 0 nodes first. Then recursively position their branches. for (let level in distribution) { if (distribution.hasOwnProperty(level)) { // sort nodes in level by position: let nodeArray = Object.keys(distribution[level]); nodeArray = this._indexArrayToNodes(nodeArray); this._sortNodeArray(nodeArray); let handledNodeCount = 0; for (let i = 0; i < nodeArray.length; i++) { let node = nodeArray[i]; if (this.positionedNodes[node.id] === undefined) { let spacing = this.options.hierarchical.nodeSpacing; let pos = spacing * handledNodeCount; // We get the X or Y values we need and store them in pos and previousPos. // The get and set make sure we get X or Y if (handledNodeCount > 0) { pos = this._getPositionForHierarchy(nodeArray[i-1]) + spacing; } this._setPositionForHierarchy(node, pos, level); this._validatePositionAndContinue(node, level, pos); handledNodeCount++; } } } } } /** * This is a recursively called function to enumerate the branches from the largest hubs and place the nodes * on a X position that ensures there will be no overlap. * * @param {vis.Node.id} parentId * @param {Number} parentLevel * @private */ _placeBranchNodes(parentId, parentLevel) { let childRef = this.hierarchical.childrenReference[parentId]; // if this is not a parent, cancel the placing. This can happen with multiple parents to one child. if (childRef === undefined) { return; } // get a list of childNodes let childNodes = []; for (let i = 0; i < childRef.length; i++) { childNodes.push(this.body.nodes[childRef[i]]); } // use the positions to order the nodes. this._sortNodeArray(childNodes); // position the childNodes for (let i = 0; i < childNodes.length; i++) { let childNode = childNodes[i]; let childNodeLevel = this.hierarchical.levels[childNode.id]; // check if the child node is below the parent node and if it has already been positioned. if (childNodeLevel > parentLevel && this.positionedNodes[childNode.id] === undefined) { // get the amount of space required for this node. If parent the width is based on the amount of children. let spacing = this.options.hierarchical.nodeSpacing; let pos; // we get the X or Y values we need and store them in pos and previousPos. // The get and set make sure we get X or Y if (i === 0) {pos = this._getPositionForHierarchy(this.body.nodes[parentId]);} else {pos = this._getPositionForHierarchy(childNodes[i-1]) + spacing;} this._setPositionForHierarchy(childNode, pos, childNodeLevel); this._validatePositionAndContinue(childNode, childNodeLevel, pos); } else { return; } } // center the parent nodes. let center = this._getCenterPosition(childNodes); this._setPositionForHierarchy(this.body.nodes[parentId], center, parentLevel); } /** * This method checks for overlap and if required shifts the branch. It also keeps records of positioned nodes. * Finally it will call _placeBranchNodes to place the branch nodes. * @param {vis.Node} node * @param {Number} level * @param {Number} pos * @private */ _validatePositionAndContinue(node, level, pos) { // This method only works for formal trees and formal forests // Early exit if this is not the case if (!this.hierarchical.isTree) return; // if overlap has been detected, we shift the branch if (this.lastNodeOnLevel[level] !== undefined) { let previousPos = this._getPositionForHierarchy(this.body.nodes[this.lastNodeOnLevel[level]]); if (pos - previousPos < this.options.hierarchical.nodeSpacing) { let diff = (previousPos + this.options.hierarchical.nodeSpacing) - pos; let sharedParent = this._findCommonParent(this.lastNodeOnLevel[level], node.id); this._shiftBlock(sharedParent.withChild, diff); } } this.lastNodeOnLevel[level] = node.id; // store change in position. this.positionedNodes[node.id] = true; this._placeBranchNodes(node.id, level); } /** * Receives an array with node indices and returns an array with the actual node references. * Used for sorting based on node properties. * @param {Array} idArray * @returns {Array} */ _indexArrayToNodes(idArray) { let array = []; for (let i = 0; i < idArray.length; i++) { array.push(this.body.nodes[idArray[i]]) } return array; } /** * This function get the distribution of levels based on hubsize * * @returns {Object} * @private */ _getDistribution() { let distribution = {}; let nodeId, node; // we fix Y because the hierarchy is vertical, // we fix X so we do not give a node an x position for a second time. // the fix of X is removed after the x value has been set. for (nodeId in this.body.nodes) { if (this.body.nodes.hasOwnProperty(nodeId)) { node = this.body.nodes[nodeId]; let level = this.hierarchical.levels[nodeId] === undefined ? 0 : this.hierarchical.levels[nodeId]; if(this._isVertical()) { node.y = this.options.hierarchical.levelSeparation * level; node.options.fixed.y = true; } else { node.x = this.options.hierarchical.levelSeparation * level; node.options.fixed.x = true; } if (distribution[level] === undefined) { distribution[level] = {}; } distribution[level][nodeId] = node; } } return distribution; } /** * Return the active (i.e. visible) edges for this node * * @param {vis.Node} node * @returns {Array} Array of edge instances * @private */ _getActiveEdges(node) { let result = []; for (let j in node.edges) { let edge = node.edges[j]; if (this.body.edgeIndices.indexOf(edge.id) !== -1) { result.push(edge); } } return result; } /** * Get the hubsizes for all active nodes. * * @returns {number} * @private */ _getHubSizes() { let hubSizes = {}; let nodeIds = this.body.nodeIndices; for (let i in nodeIds) { let nodeId = nodeIds[i]; let node = this.body.nodes[nodeId]; let hubSize = this._getActiveEdges(node).length; hubSizes[hubSize] = true; } // Make an array of the size sorted descending let result = []; for (let size in hubSizes) { result.push(Number(size)); } result.sort(function(a, b) { return b - a; }); return result; } /** * this function allocates nodes in levels based on the recursive branching from the largest hubs. * * @private */ _determineLevelsByHubsize() { let levelDownstream = (nodeA, nodeB) => { this.hierarchical.levelDownstream(nodeA, nodeB); } let hubSizes = this._getHubSizes(); for (let i = 0; i < hubSizes.length; ++i ) { let hubSize = hubSizes[i]; if (hubSize === 0) break; let nodeIds = this.body.nodeIndices; for (let j in nodeIds) { let nodeId = nodeIds[j]; let node = this.body.nodes[nodeId]; if (hubSize === this._getActiveEdges(node).length) { this._crawlNetwork(levelDownstream, nodeId); } } } } /** * TODO: release feature * TODO: Determine if this feature is needed at all * * @private */ _determineLevelsCustomCallback() { let minLevel = 100000; // TODO: this should come from options. let customCallback = function(nodeA, nodeB, edge) { // eslint-disable-line no-unused-vars }; // TODO: perhaps move to HierarchicalStatus. // But I currently don't see the point, this method is not used. let levelByDirection = (nodeA, nodeB, edge) => { let levelA = this.hierarchical.levels[nodeA.id]; // set initial level if (levelA === undefined) { levelA = this.hierarchical.levels[nodeA.id] = minLevel;} let diff = customCallback( NetworkUtil.cloneOptions(nodeA,'node'), NetworkUtil.cloneOptions(nodeB,'node'), NetworkUtil.cloneOptions(edge,'edge') ); this.hierarchical.levels[nodeB.id] = levelA + diff; }; this._crawlNetwork(levelByDirection); this.hierarchical.setMinLevelToZero(this.body.nodes); } /** * Allocate nodes in levels based on the direction of the edges. * * @private */ _determineLevelsDirected() { let minLevel = 10000; /** * Check if there is an edge going the opposite direction for given edge */ let self = this; let isBidirectional = (edge) => { for (let key in self.body.edges) { let otherEdge = self.body.edges[key]; if (otherEdge.toId === edge.fromId && otherEdge.fromId === edge.toId) { return true; } } return false; }; let levelByDirection = (nodeA, nodeB, edge) => { let levelA = this.hierarchical.levels[nodeA.id]; let levelB = this.hierarchical.levels[nodeB.id]; if (isBidirectional(edge) && levelA !== undefined && levelB !== undefined) { // Don't redo the level determination if already done in this case. return; } // set initial level if (levelA === undefined) { levelA = this.hierarchical.levels[nodeA.id] = minLevel;} if (edge.toId == nodeB.id) { this.hierarchical.levels[nodeB.id] = levelA + 1; } else { this.hierarchical.levels[nodeB.id] = levelA - 1; } }; this._crawlNetwork(levelByDirection); this.hierarchical.setMinLevelToZero(this.body.nodes); } /** * Update the bookkeeping of parent and child. * @private */ _generateMap() { let fillInRelations = (parentNode, childNode) => { if (this.hierarchical.levels[childNode.id] > this.hierarchical.levels[parentNode.id]) { this.hierarchical.addRelation(parentNode.id, childNode.id); } }; this._crawlNetwork(fillInRelations); this.hierarchical.checkIfTree(); } /** * Crawl over the entire network and use a callback on each node couple that is connected to each other. * @param {function} [callback=function(){}] | will receive nodeA, nodeB and the connecting edge. A and B are distinct. * @param {vis.Node.id} startingNodeId * @private */ _crawlNetwork(callback = function() {}, startingNodeId) { let progress = {}; let crawler = (node, tree) => { if (progress[node.id] === undefined) { this.hierarchical.setTreeIndex(node, tree); progress[node.id] = true; let childNode; let edges = this._getActiveEdges(node); for (let i = 0; i < edges.length; i++) { let edge = edges[i]; if (edge.connected === true) { if (edge.toId == node.id) { // Not '===' because id's can be string and numeric childNode = edge.from; } else { childNode = edge.to; } if (node.id != childNode.id) { // Not '!==' because id's can be string and numeric callback(node, childNode, edge); crawler(childNode, tree); } } } } }; if (startingNodeId === undefined) { // Crawl over all nodes let treeIndex = 0; // Serves to pass a unique id for the current distinct tree for (let i = 0; i < this.body.nodeIndices.length; i++) { let nodeId = this.body.nodeIndices[i]; if (progress[nodeId] === undefined) { let node = this.body.nodes[nodeId]; crawler(node, treeIndex); treeIndex += 1; } } } else { // Crawl from the given starting node let node = this.body.nodes[startingNodeId]; if (node === undefined) { console.error("Node not found:", startingNodeId); return; } crawler(node); } } /** * Shift a branch a certain distance * @param {vis.Node.id} parentId * @param {number} diff * @private */ _shiftBlock(parentId, diff) { let progress = {}; let shifter = (parentId) => { if (progress[parentId]) { return; } progress[parentId] = true; if(this._isVertical()) { this.body.nodes[parentId].x += diff; } else { this.body.nodes[parentId].y += diff; } let childRef = this.hierarchical.childrenReference[parentId]; if (childRef !== undefined) { for (let i = 0; i < childRef.length; i++) { shifter(childRef[i]); } } }; shifter(parentId); } /** * Find a common parent between branches. * @param {vis.Node.id} childA * @param {vis.Node.id} childB * @returns {{foundParent, withChild}} * @private */ _findCommonParent(childA,childB) { let parents = {}; let iterateParents = (parents,child) => { let parentRef = this.hierarchical.parentReference[child]; if (parentRef !== undefined) { for (let i = 0; i < parentRef.length; i++) { let parent = parentRef[i]; parents[parent] = true; iterateParents(parents, parent) } } }; let findParent = (parents, child) => { let parentRef = this.hierarchical.parentReference[child]; if (parentRef !== undefined) { for (let i = 0; i < parentRef.length; i++) { let parent = parentRef[i]; if (parents[parent] !== undefined) { return {foundParent:parent, withChild:child}; } let branch = findParent(parents, parent); if (branch.foundParent !== null) { return branch; } } } return {foundParent:null, withChild:child}; }; iterateParents(parents, childA); return findParent(parents, childB); } /** * Abstract the getting of the position so we won't have to repeat the check for direction all the time * @param {vis.Node} node * @param {{x: Number, y: Number}} position * @param {Number} level * @param {boolean} [doNotUpdate=false] * @private */ _setPositionForHierarchy(node, position, level, doNotUpdate = false) { //console.log('_setPositionForHierarchy',node.id, position) if (doNotUpdate !== true) { this.hierarchical.addToOrdering(node, level); } if(this._isVertical()) { node.x = position; } else { node.y = position; } } /** * Utility function to cut down on typing this all the time. * * TODO: use this in all applicable situations in this class. * @returns {boolean} * @private */ _isVertical() { return (this.options.hierarchical.direction === 'UD' || this.options.hierarchical.direction === 'DU'); } /** * Abstract the getting of the position of a node so we do not have to repeat the direction check all the time. * @param {vis.Node} node * @returns {number|*} * @private */ _getPositionForHierarchy(node) { if(this._isVertical()) { return node.x; } else { return node.y; } } /** * Use the x or y value to sort the array, allowing users to specify order. * * @param {Array} nodeArray * @private */ _sortNodeArray(nodeArray) { if (nodeArray.length > 1) { if(this._isVertical()) { nodeArray.sort(function (a, b) { return a.x - b.x; }) } else { nodeArray.sort(function (a, b) { return a.y - b.y; }) } } } /** * Get the type of static smooth curve in case it is required. * * The return value is the type to use to translate dynamic curves to * another type, in the case of hierarchical layout. Dynamic curves do * not work for that layout type. * @returns {'horizontal'|'vertical'} */ getStaticType() { // Node that 'type' is the edge type, and therefore 'orthogonal' to the layout type. let type = 'horizontal'; if (!this._isVertical()) { type = 'vertical'; } return type; } /** * Determine the center position of a branch from the passed list of child nodes * * This takes into account the positions of all the child nodes. * @param {Array} childNodes Array of either child nodes or node id's * @return {number} * @private */ _getCenterPosition(childNodes) { let minPos = 1e9; let maxPos = -1e9; for (let i = 0; i < childNodes.length; i++) { let childNode; if (childNodes[i].id !== undefined) { childNode = childNodes[i]; } else { let childNodeId = childNodes[i]; childNode = this.body.nodes[childNodeId]; } let position = this._getPositionForHierarchy(childNode); minPos = Math.min(minPos, position); maxPos = Math.max(maxPos, position); } return 0.5 * (minPos + maxPos); } } export default LayoutEngine;