var util = require('../../util'); class LayoutEngine { constructor(body) { this.body = body; this.initialRandomSeed = Math.round(Math.random() * 1000000); this.randomSeed = this.initialRandomSeed; this.options = {}; this.optionsBackup = {}; this.defaultOptions = { randomSeed: undefined, hierarchical: { enabled:false, levelSeparation: 150, direction: 'UD', // UD, DU, LR, RL sortMethod: 'hubsize' // hubsize, directed } }; util.extend(this.options, this.defaultOptions); this.hierarchicalLevels = {}; this.bindEventListeners(); } bindEventListeners() { this.body.emitter.on('_dataChanged', () => { this.setupHierarchicalLayout(); }); this.body.emitter.on('_resetHierarchicalLayout', () => { this.setupHierarchicalLayout(); }); } setOptions(options, allOptions) { if (options !== undefined) { let prevHierarchicalState = this.options.hierarchical.enabled; util.mergeOptions(this.options, options, 'hierarchical'); if (options.randomSeed !== undefined) { this.randomSeed = options.randomSeed; } if (this.options.hierarchical.enabled === true) { // make sure the level seperation is the right way up if (this.options.hierarchical.direction === 'RL' || this.options.hierarchical.direction === 'DU') { if (this.options.hierarchical.levelSeparation > 0) { this.options.hierarchical.levelSeparation *= -1; } } else { if (this.options.hierarchical.levelSeparation < 0) { this.options.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.adaptAllOptions(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; } adaptAllOptions(allOptions) { if (this.options.hierarchical.enabled === true) { // set the physics if (allOptions.physics === undefined || allOptions.physics === true) { allOptions.physics = {solver: 'hierarchicalRepulsion'}; this.optionsBackup.physics = {solver:'barnesHut'}; } else if (typeof options.physics === 'object') { this.optionsBackup.physics = {solver:'barnesHut'}; if (options.physics.solver !== undefined) { this.optionsBackup.physics = {solver:options.physics.solver}; } allOptions.physics['solver'] = 'hierarchicalRepulsion'; } else if (options.physics !== false) { this.optionsBackup.physics = {solver:'barnesHut'}; allOptions.physics['solver'] = 'hierarchicalRepulsion'; } // get the type of static smooth curve in case it is required let type = 'horizontal'; if (this.options.hierarchical.direction === 'RL' || this.options.hierarchical.direction === 'LR') { type = 'vertical'; } // 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:true, dynamic:true}; allOptions.edges = {smooth: false}; } else if (allOptions.edges.smooth === undefined) { this.optionsBackup.edges = {smooth:true, dynamic:true}; allOptions.edges.smooth = false; } else { if (typeof allOptions.edges.smooth === 'boolean') { this.optionsBackup.edges = {smooth:allOptions.edges.smooth, dynamic:true}; allOptions.edges.smooth = {enabled: allOptions.edges.smooth, dynamic: false, type:type} } else { this.optionsBackup.edges = {smooth: allOptions.edges.smooth.enabled === undefined ? true : allOptions.edges.smooth.enabled, dynamic:true}; allOptions.edges.smooth = {enabled: allOptions.edges.smooth.enabled === undefined ? true : allOptions.edges.smooth.enabled, dynamic: false, type:type} } } // 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; } seededRandom() { var x = Math.sin(this.randomSeed++) * 10000; return x - Math.floor(x); } positionInitially(nodesArray) { if (this.options.hierarchical.enabled !== true) { for (let i = 0; i < nodesArray.length; i++) { let node = nodesArray[i]; if ((!node.isFixed()) && (node.x === undefined || node.y === undefined)) { let radius = 10 * 0.1 * nodesArray.length + 10; let angle = 2 * Math.PI * this.seededRandom(); if (node.options.fixed.x === false) { node.x = radius * Math.cos(angle); } if (node.options.fixed.x === false) { node.y = radius * Math.sin(angle); } } } } } 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.hierarchicalLevels = {}; this.nodeSpacing = 100; 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.hierarchicalLevels[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.'); return; } else { // setup the system to use hierarchical method. //this._changeConstants(); // define levels if undefined by the users. Based on hubsize if (undefinedLevel === true) { if (this.options.hierarchical.sortMethod === 'hubsize') { this._determineLevelsByHubsize(); } else if (this.options.hierarchical.sortMethod === 'directed' || 'direction') { this._determineLevelsDirected(); } } // check the distribution of the nodes per level. let distribution = this._getDistribution(); // place the nodes on the canvas. this._placeNodesByHierarchy(distribution); } } } /** * 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) { let nodeId, node; this.positionedNodes = {}; // start placing all the level 0 nodes first. Then recursively position their branches. for (let level in distribution) { if (distribution.hasOwnProperty(level)) { for (nodeId in distribution[level].nodes) { if (distribution[level].nodes.hasOwnProperty(nodeId)) { node = distribution[level].nodes[nodeId]; if (this.options.hierarchical.direction === 'UD' || this.options.hierarchical.direction === 'DU') { if (node.x === undefined) {node.x = distribution[level].distance;} distribution[level].distance = node.x + this.nodeSpacing; } else { if (node.y === undefined) {node.y = distribution[level].distance;} distribution[level].distance = node.y + this.nodeSpacing; } this.positionedNodes[nodeId] = true; this._placeBranchNodes(node.edges,node.id,distribution,level); } } } } } /** * 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.hierarchicalLevels[nodeId] === undefined ? 0 : this.hierarchicalLevels[nodeId]; if (this.options.hierarchical.direction === 'UD' || this.options.hierarchical.direction === 'DU') { 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] = {amount: 0, nodes: {}, distance: 0}; } distribution[level].amount += 1; distribution[level].nodes[nodeId] = node; } } return distribution; } /** * Get the hubsize from all remaining unlevelled nodes. * * @returns {number} * @private */ _getHubSize() { let hubSize = 0; for (let nodeId in this.body.nodes) { if (this.body.nodes.hasOwnProperty(nodeId)) { let node = this.body.nodes[nodeId]; if (this.hierarchicalLevels[nodeId] === undefined) { hubSize = node.edges.length < hubSize ? hubSize : node.edges.length; } } } return hubSize; } /** * this function allocates nodes in levels based on the recursive branching from the largest hubs. * * @param hubsize * @private */ _determineLevelsByHubsize() { let nodeId, node; let hubSize = 1; while (hubSize > 0) { // determine hubs hubSize = this._getHubSize(); if (hubSize === 0) break; for (nodeId in this.body.nodes) { if (this.body.nodes.hasOwnProperty(nodeId)) { node = this.body.nodes[nodeId]; if (node.edges.length === hubSize) { this._setLevel(0, node); } } } } } /** * this function is called recursively to enumerate the barnches of the largest hubs and give each node a level. * * @param level * @param edges * @param parentId * @private */ _setLevel(level, node) { if (this.hierarchicalLevels[node.id] !== undefined) return; let childNode; this.hierarchicalLevels[node.id] = level; for (let i = 0; i < node.edges.length; i++) { if (node.edges[i].toId === node.id) { childNode = node.edges[i].from; } else { childNode = node.edges[i].to; } this._setLevel(level + 1, childNode); } } /** * this function allocates nodes in levels based on the direction of the edges * * @param hubsize * @private */ _determineLevelsDirected() { let nodeId, node; let minLevel = 10000; // set first node to source for (nodeId in this.body.nodes) { if (this.body.nodes.hasOwnProperty(nodeId)) { node = this.body.nodes[nodeId]; this._setLevelDirected(minLevel,node); } } // get the minimum level for (nodeId in this.body.nodes) { if (this.body.nodes.hasOwnProperty(nodeId)) { minLevel = this.hierarchicalLevels[nodeId] < minLevel ? this.hierarchicalLevels[nodeId] : minLevel; } } // subtract the minimum from the set so we have a range starting from 0 for (nodeId in this.body.nodes) { if (this.body.nodes.hasOwnProperty(nodeId)) { this.hierarchicalLevels[nodeId] -= minLevel; } } } /** * this function is called recursively to enumerate the branched of the first node and give each node a level based on edge direction * * @param level * @param edges * @param parentId * @private */ _setLevelDirected(level, node) { if (this.hierarchicalLevels[node.id] !== undefined) return; let childNode; this.hierarchicalLevels[node.id] = level; for (let i = 0; i < node.edges.length; i++) { if (node.edges[i].toId === node.id) { childNode = node.edges[i].from; this._setLevelDirected(level - 1, childNode); } else { childNode = node.edges[i].to; this._setLevelDirected(level + 1, childNode); } } } /** * 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 edges * @param parentId * @param distribution * @param parentLevel * @private */ _placeBranchNodes(edges, parentId, distribution, parentLevel) { for (let i = 0; i < edges.length; i++) { let childNode = undefined; let parentNode = undefined; if (edges[i].toId === parentId) { childNode = edges[i].from; parentNode = edges[i].to; } else { childNode = edges[i].to; parentNode = edges[i].from; } let childNodeLevel = this.hierarchicalLevels[childNode.id]; if (this.positionedNodes[childNode.id] === undefined) { // if a node is conneceted to another node on the same level (or higher (means lower level))!, this is not handled here. if (childNodeLevel > parentLevel) { if (this.options.hierarchical.direction === 'UD' || this.options.hierarchical.direction === 'DU') { if (childNode.x === undefined) { childNode.x = Math.max(distribution[childNodeLevel].distance, parentNode.x); } distribution[childNodeLevel].distance = childNode.x + this.nodeSpacing; this.positionedNodes[childNode.id] = true; } else { if (childNode.y === undefined) { childNode.y = Math.max(distribution[childNodeLevel].distance, parentNode.y) } distribution[childNodeLevel].distance = childNode.y + this.nodeSpacing; } this.positionedNodes[childNode.id] = true; if (childNode.edges.length > 1) { this._placeBranchNodes(childNode.edges, childNode.id, distribution, childNodeLevel); } } } } } } export default LayoutEngine;