var util = require('../../util'); var DOMutil = require('../../DOMutil'); var DataSet = require('../../DataSet'); var DataView = require('../../DataView'); var Component = require('./Component'); var DataAxis = require('./DataAxis'); var GraphGroup = require('./GraphGroup'); var Legend = require('./Legend'); var UNGROUPED = '__ungrouped__'; // reserved group id for ungrouped items /** * This is the constructor of the LineGraph. It requires a Timeline body and options. * * @param body * @param options * @constructor */ function LineGraph(body, options) { this.id = util.randomUUID(); this.body = body; this.defaultOptions = { yAxisOrientation: 'left', defaultGroup: 'default', sort: true, sampling: true, graphHeight: '400px', shaded: { enabled: false, orientation: 'bottom' // top, bottom }, style: 'line', // line, bar barChart: { width: 50, align: 'center' // left, center, right }, catmullRom: { enabled: true, parametrization: 'centripetal', // uniform (alpha = 0.0), chordal (alpha = 1.0), centripetal (alpha = 0.5) alpha: 0.5 }, drawPoints: { enabled: true, size: 6, style: 'square' // square, circle }, dataAxis: { showMinorLabels: true, showMajorLabels: true, icons: false, width: '40px', visible: true }, legend: { enabled: false, icons: true, left: { visible: true, position: 'top-left' // top/bottom - left,right }, right: { visible: true, position: 'top-right' // top/bottom - left,right } } }; // options is shared by this ItemSet and all its items this.options = util.extend({}, this.defaultOptions); this.dom = {}; this.props = {}; this.hammer = null; this.groups = {}; var me = this; this.itemsData = null; // DataSet this.groupsData = null; // DataSet // listeners for the DataSet of the items this.itemListeners = { 'add': function (event, params, senderId) { me._onAdd(params.items); }, 'update': function (event, params, senderId) { me._onUpdate(params.items); }, 'remove': function (event, params, senderId) { me._onRemove(params.items); } }; // listeners for the DataSet of the groups this.groupListeners = { 'add': function (event, params, senderId) { me._onAddGroups(params.items); }, 'update': function (event, params, senderId) { me._onUpdateGroups(params.items); }, 'remove': function (event, params, senderId) { me._onRemoveGroups(params.items); } }; this.items = {}; // object with an Item for every data item this.selection = []; // list with the ids of all selected nodes this.lastStart = this.body.range.start; this.touchParams = {}; // stores properties while dragging this.svgElements = {}; this.setOptions(options); this.groupsUsingDefaultStyles = [0]; this.body.emitter.on("rangechange",function() { if (me.lastStart != 0) { var offset = me.body.range.start - me.lastStart; var range = me.body.range.end - me.body.range.start; if (me.width != 0) { var rangePerPixelInv = me.width/range; var xOffset = offset * rangePerPixelInv; me.svg.style.left = (-me.width - xOffset) + "px"; } } }); this.body.emitter.on("rangechanged", function() { me.lastStart = me.body.range.start; me.svg.style.left = util.option.asSize(-me.width); me._updateGraph.apply(me); }); // create the HTML DOM this._create(); this.body.emitter.emit("change"); } LineGraph.prototype = new Component(); /** * Create the HTML DOM for the ItemSet */ LineGraph.prototype._create = function(){ var frame = document.createElement('div'); frame.className = 'LineGraph'; this.dom.frame = frame; // create svg element for graph drawing. this.svg = document.createElementNS('http://www.w3.org/2000/svg',"svg"); this.svg.style.position = "relative"; this.svg.style.height = ('' + this.options.graphHeight).replace("px",'') + 'px'; this.svg.style.display = "block"; frame.appendChild(this.svg); // data axis this.options.dataAxis.orientation = 'left'; this.yAxisLeft = new DataAxis(this.body, this.options.dataAxis, this.svg); this.options.dataAxis.orientation = 'right'; this.yAxisRight = new DataAxis(this.body, this.options.dataAxis, this.svg); delete this.options.dataAxis.orientation; // legends this.legendLeft = new Legend(this.body, this.options.legend, 'left'); this.legendRight = new Legend(this.body, this.options.legend, 'right'); this.show(); }; /** * set the options of the LineGraph. the mergeOptions is used for subObjects that have an enabled element. * @param options */ LineGraph.prototype.setOptions = function(options) { if (options) { var fields = ['sampling','defaultGroup','graphHeight','yAxisOrientation','style','barChart','dataAxis','sort']; util.selectiveDeepExtend(fields, this.options, options); util.mergeOptions(this.options, options,'catmullRom'); util.mergeOptions(this.options, options,'drawPoints'); util.mergeOptions(this.options, options,'shaded'); util.mergeOptions(this.options, options,'legend'); if (options.catmullRom) { if (typeof options.catmullRom == 'object') { if (options.catmullRom.parametrization) { if (options.catmullRom.parametrization == 'uniform') { this.options.catmullRom.alpha = 0; } else if (options.catmullRom.parametrization == 'chordal') { this.options.catmullRom.alpha = 1.0; } else { this.options.catmullRom.parametrization = 'centripetal'; this.options.catmullRom.alpha = 0.5; } } } } if (this.yAxisLeft) { if (options.dataAxis !== undefined) { this.yAxisLeft.setOptions(this.options.dataAxis); this.yAxisRight.setOptions(this.options.dataAxis); } } if (this.legendLeft) { if (options.legend !== undefined) { this.legendLeft.setOptions(this.options.legend); this.legendRight.setOptions(this.options.legend); } } if (this.groups.hasOwnProperty(UNGROUPED)) { this.groups[UNGROUPED].setOptions(options); } } if (this.dom.frame) { this._updateGraph(); } }; /** * Hide the component from the DOM */ LineGraph.prototype.hide = function() { // remove the frame containing the items if (this.dom.frame.parentNode) { this.dom.frame.parentNode.removeChild(this.dom.frame); } }; /** * Show the component in the DOM (when not already visible). * @return {Boolean} changed */ LineGraph.prototype.show = function() { // show frame containing the items if (!this.dom.frame.parentNode) { this.body.dom.center.appendChild(this.dom.frame); } }; /** * Set items * @param {vis.DataSet | null} items */ LineGraph.prototype.setItems = function(items) { var me = this, ids, oldItemsData = this.itemsData; // replace the dataset if (!items) { this.itemsData = null; } else if (items instanceof DataSet || items instanceof DataView) { this.itemsData = items; } else { throw new TypeError('Data must be an instance of DataSet or DataView'); } if (oldItemsData) { // unsubscribe from old dataset util.forEach(this.itemListeners, function (callback, event) { oldItemsData.off(event, callback); }); // remove all drawn items ids = oldItemsData.getIds(); this._onRemove(ids); } if (this.itemsData) { // subscribe to new dataset var id = this.id; util.forEach(this.itemListeners, function (callback, event) { me.itemsData.on(event, callback, id); }); // add all new items ids = this.itemsData.getIds(); this._onAdd(ids); } this._updateUngrouped(); this._updateGraph(); this.redraw(); }; /** * Set groups * @param {vis.DataSet} groups */ LineGraph.prototype.setGroups = function(groups) { var me = this, ids; // unsubscribe from current dataset if (this.groupsData) { util.forEach(this.groupListeners, function (callback, event) { me.groupsData.unsubscribe(event, callback); }); // remove all drawn groups ids = this.groupsData.getIds(); this.groupsData = null; this._onRemoveGroups(ids); // note: this will cause a redraw } // replace the dataset if (!groups) { this.groupsData = null; } else if (groups instanceof DataSet || groups instanceof DataView) { this.groupsData = groups; } else { throw new TypeError('Data must be an instance of DataSet or DataView'); } if (this.groupsData) { // subscribe to new dataset var id = this.id; util.forEach(this.groupListeners, function (callback, event) { me.groupsData.on(event, callback, id); }); // draw all ms ids = this.groupsData.getIds(); this._onAddGroups(ids); } this._onUpdate(); }; LineGraph.prototype._onUpdate = function(ids) { this._updateUngrouped(); this._updateAllGroupData(); this._updateGraph(); this.redraw(); }; LineGraph.prototype._onAdd = function (ids) {this._onUpdate(ids);}; LineGraph.prototype._onRemove = function (ids) {this._onUpdate(ids);}; LineGraph.prototype._onUpdateGroups = function (groupIds) { for (var i = 0; i < groupIds.length; i++) { var group = this.groupsData.get(groupIds[i]); this._updateGroup(group, groupIds[i]); } this._updateGraph(); this.redraw(); }; LineGraph.prototype._onAddGroups = function (groupIds) {this._onUpdateGroups(groupIds);}; LineGraph.prototype._onRemoveGroups = function (groupIds) { for (var i = 0; i < groupIds.length; i++) { if (!this.groups.hasOwnProperty(groupIds[i])) { if (this.groups[groupIds[i]].options.yAxisOrientation == 'right') { this.yAxisRight.removeGroup(groupIds[i]); this.legendRight.removeGroup(groupIds[i]); this.legendRight.redraw(); } else { this.yAxisLeft.removeGroup(groupIds[i]); this.legendLeft.removeGroup(groupIds[i]); this.legendLeft.redraw(); } delete this.groups[groupIds[i]]; } } this._updateUngrouped(); this._updateGraph(); this.redraw(); }; /** * update a group object * * @param group * @param groupId * @private */ LineGraph.prototype._updateGroup = function (group, groupId) { if (!this.groups.hasOwnProperty(groupId)) { this.groups[groupId] = new GraphGroup(group, groupId, this.options, this.groupsUsingDefaultStyles); if (this.groups[groupId].options.yAxisOrientation == 'right') { this.yAxisRight.addGroup(groupId, this.groups[groupId]); this.legendRight.addGroup(groupId, this.groups[groupId]); } else { this.yAxisLeft.addGroup(groupId, this.groups[groupId]); this.legendLeft.addGroup(groupId, this.groups[groupId]); } } else { this.groups[groupId].update(group); if (this.groups[groupId].options.yAxisOrientation == 'right') { this.yAxisRight.updateGroup(groupId, this.groups[groupId]); this.legendRight.updateGroup(groupId, this.groups[groupId]); } else { this.yAxisLeft.updateGroup(groupId, this.groups[groupId]); this.legendLeft.updateGroup(groupId, this.groups[groupId]); } } this.legendLeft.redraw(); this.legendRight.redraw(); }; LineGraph.prototype._updateAllGroupData = function () { if (this.itemsData != null) { // ~450 ms @ 500k var groupsContent = {}; for (var groupId in this.groups) { if (this.groups.hasOwnProperty(groupId)) { groupsContent[groupId] = []; } } for (var itemId in this.itemsData._data) { if (this.itemsData._data.hasOwnProperty(itemId)) { var item = this.itemsData._data[itemId]; item.x = util.convert(item.x,"Date"); groupsContent[item.group].push(item); } } for (var groupId in this.groups) { if (this.groups.hasOwnProperty(groupId)) { this.groups[groupId].setItems(groupsContent[groupId]); } } // // ~4500ms @ 500k // for (var groupId in this.groups) { // if (this.groups.hasOwnProperty(groupId)) { // this.groups[groupId].setItems(this.itemsData.get({filter: // function (item) { // return (item.group == groupId); // }, type:{x:"Date"}} // )); // } // } } }; /** * Create or delete the group holding all ungrouped items. This group is used when * there are no groups specified. This anonymous group is called 'graph'. * @protected */ LineGraph.prototype._updateUngrouped = function() { if (this.itemsData != null) { // var t0 = new Date(); var group = {id: UNGROUPED, content: this.options.defaultGroup}; this._updateGroup(group, UNGROUPED); var ungroupedCounter = 0; if (this.itemsData) { for (var itemId in this.itemsData._data) { if (this.itemsData._data.hasOwnProperty(itemId)) { var item = this.itemsData._data[itemId]; if (item != undefined) { if (item.hasOwnProperty('group')) { if (item.group === undefined) { item.group = UNGROUPED; } } else { item.group = UNGROUPED; } ungroupedCounter = item.group == UNGROUPED ? ungroupedCounter + 1 : ungroupedCounter; } } } } // much much slower // var datapoints = this.itemsData.get({ // filter: function (item) {return item.group === undefined;}, // showInternalIds:true // }); // if (datapoints.length > 0) { // var updateQuery = []; // for (var i = 0; i < datapoints.length; i++) { // updateQuery.push({id:datapoints[i].id, group: UNGROUPED}); // } // this.itemsData.update(updateQuery, true); // } // var t1 = new Date(); // var pointInUNGROUPED = this.itemsData.get({filter: function (item) {return item.group == UNGROUPED;}}); if (ungroupedCounter == 0) { delete this.groups[UNGROUPED]; this.legendLeft.removeGroup(UNGROUPED); this.legendRight.removeGroup(UNGROUPED); this.yAxisLeft.removeGroup(UNGROUPED); this.yAxisRight.removeGroup(UNGROUPED); } // console.log("getting amount ungrouped",new Date() - t1); // console.log("putting in ungrouped",new Date() - t0); } else { delete this.groups[UNGROUPED]; this.legendLeft.removeGroup(UNGROUPED); this.legendRight.removeGroup(UNGROUPED); this.yAxisLeft.removeGroup(UNGROUPED); this.yAxisRight.removeGroup(UNGROUPED); } this.legendLeft.redraw(); this.legendRight.redraw(); }; /** * Redraw the component, mandatory function * @return {boolean} Returns true if the component is resized */ LineGraph.prototype.redraw = function() { var resized = false; this.svg.style.height = ('' + this.options.graphHeight).replace('px','') + 'px'; if (this.lastWidth === undefined && this.width || this.lastWidth != this.width) { resized = true; } // check if this component is resized resized = this._isResized() || resized; // check whether zoomed (in that case we need to re-stack everything) var visibleInterval = this.body.range.end - this.body.range.start; var zoomed = (visibleInterval != this.lastVisibleInterval) || (this.width != this.lastWidth); this.lastVisibleInterval = visibleInterval; this.lastWidth = this.width; // calculate actual size and position this.width = this.dom.frame.offsetWidth; // the svg element is three times as big as the width, this allows for fully dragging left and right // without reloading the graph. the controls for this are bound to events in the constructor if (resized == true) { this.svg.style.width = util.option.asSize(3*this.width); this.svg.style.left = util.option.asSize(-this.width); } if (zoomed == true) { this._updateGraph(); } this.legendLeft.redraw(); this.legendRight.redraw(); return resized; }; /** * Update and redraw the graph. * */ LineGraph.prototype._updateGraph = function () { // reset the svg elements DOMutil.prepareElements(this.svgElements); // // very slow... // groupData = group.itemsData.get({filter: // function (item) { // return (item.x > minDate && item.x < maxDate); // }} // ); if (this.width != 0 && this.itemsData != null) { var group, groupData, preprocessedGroup, i; var preprocessedGroupData = []; var processedGroupData = []; var groupRanges = []; var changeCalled = false; // getting group Ids var groupIds = []; for (var groupId in this.groups) { if (this.groups.hasOwnProperty(groupId)) { groupIds.push(groupId); } } // this is the range of the SVG canvas var minDate = this.body.util.toGlobalTime(- this.body.domProps.root.width); var maxDate = this.body.util.toGlobalTime(2 * this.body.domProps.root.width); // first select and preprocess the data from the datasets. // the groups have their preselection of data, we now loop over this data to see // what data we need to draw. Sorted data is much faster. // more optimization is possible by doing the sampling before and using the binary search // to find the end date to determine the increment. if (groupIds.length > 0) { for (i = 0; i < groupIds.length; i++) { group = this.groups[groupIds[i]]; groupData = []; // optimization for sorted data if (group.options.sort == true) { var guess = Math.max(0,util.binarySearchGeneric(group.itemsData, minDate, 'x', 'before')); for (var j = guess; j < group.itemsData.length; j++) { var item = group.itemsData[j]; if (item !== undefined) { if (item.x > maxDate) { groupData.push(item); break; } else { groupData.push(item); } } } } else { for (var j = 0; j < group.itemsData.length; j++) { var item = group.itemsData[j]; if (item !== undefined) { if (item.x > minDate && item.x < maxDate) { groupData.push(item); } } } } // preprocess, split into ranges and data preprocessedGroup = this._preprocessData(groupData, group); groupRanges.push({min: preprocessedGroup.min, max: preprocessedGroup.max}); preprocessedGroupData.push(preprocessedGroup.data); } // update the Y axis first, we use this data to draw at the correct Y points // changeCalled is required to clean the SVG on a change emit. changeCalled = this._updateYAxis(groupIds, groupRanges); if (changeCalled == true) { DOMutil.cleanupElements(this.svgElements); this.body.emitter.emit("change"); return; } // with the yAxis scaled correctly, use this to get the Y values of the points. for (i = 0; i < groupIds.length; i++) { group = this.groups[groupIds[i]]; processedGroupData.push(this._convertYvalues(preprocessedGroupData[i],group)) } // draw the groups for (i = 0; i < groupIds.length; i++) { group = this.groups[groupIds[i]]; if (group.options.style == 'line') { this._drawLineGraph(processedGroupData[i], group); } else { this._drawBarGraph (processedGroupData[i], group); } } } } // cleanup unused svg elements DOMutil.cleanupElements(this.svgElements); }; /** * this sets the Y ranges for the Y axis. It also determines which of the axis should be shown or hidden. * @param {array} groupIds * @private */ LineGraph.prototype._updateYAxis = function (groupIds, groupRanges) { var changeCalled = false; var yAxisLeftUsed = false; var yAxisRightUsed = false; var minLeft = 1e9, minRight = 1e9, maxLeft = -1e9, maxRight = -1e9, minVal, maxVal; var orientation = 'left'; // if groups are present if (groupIds.length > 0) { for (var i = 0; i < groupIds.length; i++) { orientation = 'left'; var group = this.groups[groupIds[i]]; if (group.options.yAxisOrientation == 'right') { orientation = 'right'; } minVal = groupRanges[i].min; maxVal = groupRanges[i].max; if (orientation == 'left') { yAxisLeftUsed = true; minLeft = minLeft > minVal ? minVal : minLeft; maxLeft = maxLeft < maxVal ? maxVal : maxLeft; } else { yAxisRightUsed = true; minRight = minRight > minVal ? minVal : minRight; maxRight = maxRight < maxVal ? maxVal : maxRight; } } if (yAxisLeftUsed == true) { this.yAxisLeft.setRange(minLeft, maxLeft); } if (yAxisRightUsed == true) { this.yAxisRight.setRange(minRight, maxRight); } } changeCalled = this._toggleAxisVisiblity(yAxisLeftUsed , this.yAxisLeft) || changeCalled; changeCalled = this._toggleAxisVisiblity(yAxisRightUsed, this.yAxisRight) || changeCalled; if (yAxisRightUsed == true && yAxisLeftUsed == true) { this.yAxisLeft.drawIcons = true; this.yAxisRight.drawIcons = true; } else { this.yAxisLeft.drawIcons = false; this.yAxisRight.drawIcons = false; } this.yAxisRight.master = !yAxisLeftUsed; if (this.yAxisRight.master == false) { if (yAxisRightUsed == true) { this.yAxisLeft.lineOffset = this.yAxisRight.width; } changeCalled = this.yAxisLeft.redraw() || changeCalled; this.yAxisRight.stepPixelsForced = this.yAxisLeft.stepPixels; changeCalled = this.yAxisRight.redraw() || changeCalled; } else { changeCalled = this.yAxisRight.redraw() || changeCalled; } return changeCalled; }; /** * This shows or hides the Y axis if needed. If there is a change, the changed event is emitted by the updateYAxis function * * @param {boolean} axisUsed * @returns {boolean} * @private * @param axis */ LineGraph.prototype._toggleAxisVisiblity = function (axisUsed, axis) { var changed = false; if (axisUsed == false) { if (axis.dom.frame.parentNode) { axis.hide(); changed = true; } } else { if (!axis.dom.frame.parentNode) { axis.show(); changed = true; } } return changed; }; /** * draw a bar graph * @param datapoints * @param group */ LineGraph.prototype._drawBarGraph = function (dataset, group) { if (dataset != null) { if (dataset.length > 0) { var coreDistance; var minWidth = 0.1 * group.options.barChart.width; var offset = 0; var width = group.options.barChart.width; if (group.options.barChart.align == 'left') {offset -= 0.5*width;} else if (group.options.barChart.align == 'right') {offset += 0.5*width;} for (var i = 0; i < dataset.length; i++) { // dynammically downscale the width so there is no overlap up to 1/10th the original width if (i+1 < dataset.length) {coreDistance = Math.abs(dataset[i+1].x - dataset[i].x);} if (i > 0) {coreDistance = Math.min(coreDistance,Math.abs(dataset[i-1].x - dataset[i].x));} if (coreDistance < width) {width = coreDistance < minWidth ? minWidth : coreDistance;} DOMutil.drawBar(dataset[i].x + offset, dataset[i].y, width, group.zeroPosition - dataset[i].y, group.className + ' bar', this.svgElements, this.svg); } // draw points if (group.options.drawPoints.enabled == true) { this._drawPoints(dataset, group, this.svgElements, this.svg, offset); } } } }; /** * draw a line graph * * @param datapoints * @param group */ LineGraph.prototype._drawLineGraph = function (dataset, group) { if (dataset != null) { if (dataset.length > 0) { var path, d; var svgHeight = Number(this.svg.style.height.replace("px","")); path = DOMutil.getSVGElement('path', this.svgElements, this.svg); path.setAttributeNS(null, "class", group.className); // construct path from dataset if (group.options.catmullRom.enabled == true) { d = this._catmullRom(dataset, group); } else { d = this._linear(dataset); } // append with points for fill and finalize the path if (group.options.shaded.enabled == true) { var fillPath = DOMutil.getSVGElement('path',this.svgElements, this.svg); var dFill; if (group.options.shaded.orientation == 'top') { dFill = "M" + dataset[0].x + "," + 0 + " " + d + "L" + dataset[dataset.length - 1].x + "," + 0; } else { dFill = "M" + dataset[0].x + "," + svgHeight + " " + d + "L" + dataset[dataset.length - 1].x + "," + svgHeight; } fillPath.setAttributeNS(null, "class", group.className + " fill"); fillPath.setAttributeNS(null, "d", dFill); } // copy properties to path for drawing. path.setAttributeNS(null, "d", "M" + d); // draw points if (group.options.drawPoints.enabled == true) { this._drawPoints(dataset, group, this.svgElements, this.svg); } } } }; /** * draw the data points * * @param dataset * @param JSONcontainer * @param svg * @param group */ LineGraph.prototype._drawPoints = function (dataset, group, JSONcontainer, svg, offset) { if (offset === undefined) {offset = 0;} for (var i = 0; i < dataset.length; i++) { DOMutil.drawPoint(dataset[i].x + offset, dataset[i].y, group, JSONcontainer, svg); } }; /** * This uses the DataAxis object to generate the correct X coordinate on the SVG window. It uses the * util function toScreen to get the x coordinate from the timestamp. It also pre-filters the data and get the minMax ranges for * the yAxis. * * @param datapoints * @returns {Array} * @private */ LineGraph.prototype._preprocessData = function (datapoints, group) { var extractedData = []; var xValue, yValue; var toScreen = this.body.util.toScreen; var increment = 1; var amountOfPoints = datapoints.length; var yMin = datapoints[0].y; var yMax = datapoints[0].y; // the global screen is used because changing the width of the yAxis may affect the increment, resulting in an endless loop // of width changing of the yAxis. if (group.options.sampling == true) { var xDistance = this.body.util.toGlobalScreen(datapoints[datapoints.length-1].x) - this.body.util.toGlobalScreen(datapoints[0].x); var pointsPerPixel = amountOfPoints/xDistance; increment = Math.min(Math.ceil(0.2 * amountOfPoints), Math.max(1,Math.round(pointsPerPixel))); } for (var i = 0; i < amountOfPoints; i += increment) { xValue = toScreen(datapoints[i].x) + this.width - 1; yValue = datapoints[i].y; extractedData.push({x: xValue, y: yValue}); yMin = yMin > yValue ? yValue : yMin; yMax = yMax < yValue ? yValue : yMax; } // extractedData.sort(function (a,b) {return a.x - b.x;}); return {min: yMin, max: yMax, data: extractedData}; }; /** * This uses the DataAxis object to generate the correct Y coordinate on the SVG window. It uses the * util function toScreen to get the x coordinate from the timestamp. * * @param datapoints * @param options * @returns {Array} * @private */ LineGraph.prototype._convertYvalues = function (datapoints, group) { var extractedData = []; var xValue, yValue; var axis = this.yAxisLeft; var svgHeight = Number(this.svg.style.height.replace("px","")); if (group.options.yAxisOrientation == 'right') { axis = this.yAxisRight; } for (var i = 0; i < datapoints.length; i++) { xValue = datapoints[i].x; yValue = Math.round(axis.convertValue(datapoints[i].y)); extractedData.push({x: xValue, y: yValue}); } group.setZeroPosition(Math.min(svgHeight, axis.convertValue(0))); // extractedData.sort(function (a,b) {return a.x - b.x;}); return extractedData; }; /** * This uses an uniform parametrization of the CatmullRom algorithm: * "On the Parameterization of Catmull-Rom Curves" by Cem Yuksel et al. * @param data * @returns {string} * @private */ LineGraph.prototype._catmullRomUniform = function(data) { // catmull rom var p0, p1, p2, p3, bp1, bp2; var d = Math.round(data[0].x) + "," + Math.round(data[0].y) + " "; var normalization = 1/6; var length = data.length; for (var i = 0; i < length - 1; i++) { p0 = (i == 0) ? data[0] : data[i-1]; p1 = data[i]; p2 = data[i+1]; p3 = (i + 2 < length) ? data[i+2] : p2; // Catmull-Rom to Cubic Bezier conversion matrix // 0 1 0 0 // -1/6 1 1/6 0 // 0 1/6 1 -1/6 // 0 0 1 0 // bp0 = { x: p1.x, y: p1.y }; bp1 = { x: ((-p0.x + 6*p1.x + p2.x) *normalization), y: ((-p0.y + 6*p1.y + p2.y) *normalization)}; bp2 = { x: (( p1.x + 6*p2.x - p3.x) *normalization), y: (( p1.y + 6*p2.y - p3.y) *normalization)}; // bp0 = { x: p2.x, y: p2.y }; d += "C" + bp1.x + "," + bp1.y + " " + bp2.x + "," + bp2.y + " " + p2.x + "," + p2.y + " "; } return d; }; /** * This uses either the chordal or centripetal parameterization of the catmull-rom algorithm. * By default, the centripetal parameterization is used because this gives the nicest results. * These parameterizations are relatively heavy because the distance between 4 points have to be calculated. * * One optimization can be used to reuse distances since this is a sliding window approach. * @param data * @returns {string} * @private */ LineGraph.prototype._catmullRom = function(data, group) { var alpha = group.options.catmullRom.alpha; if (alpha == 0 || alpha === undefined) { return this._catmullRomUniform(data); } else { var p0, p1, p2, p3, bp1, bp2, d1,d2,d3, A, B, N, M; var d3powA, d2powA, d3pow2A, d2pow2A, d1pow2A, d1powA; var d = Math.round(data[0].x) + "," + Math.round(data[0].y) + " "; var length = data.length; for (var i = 0; i < length - 1; i++) { p0 = (i == 0) ? data[0] : data[i-1]; p1 = data[i]; p2 = data[i+1]; p3 = (i + 2 < length) ? data[i+2] : p2; d1 = Math.sqrt(Math.pow(p0.x - p1.x,2) + Math.pow(p0.y - p1.y,2)); d2 = Math.sqrt(Math.pow(p1.x - p2.x,2) + Math.pow(p1.y - p2.y,2)); d3 = Math.sqrt(Math.pow(p2.x - p3.x,2) + Math.pow(p2.y - p3.y,2)); // Catmull-Rom to Cubic Bezier conversion matrix // // A = 2d1^2a + 3d1^a * d2^a + d3^2a // B = 2d3^2a + 3d3^a * d2^a + d2^2a // // [ 0 1 0 0 ] // [ -d2^2a/N A/N d1^2a/N 0 ] // [ 0 d3^2a/M B/M -d2^2a/M ] // [ 0 0 1 0 ] // [ 0 1 0 0 ] // [ -d2pow2a/N A/N d1pow2a/N 0 ] // [ 0 d3pow2a/M B/M -d2pow2a/M ] // [ 0 0 1 0 ] d3powA = Math.pow(d3, alpha); d3pow2A = Math.pow(d3,2*alpha); d2powA = Math.pow(d2, alpha); d2pow2A = Math.pow(d2,2*alpha); d1powA = Math.pow(d1, alpha); d1pow2A = Math.pow(d1,2*alpha); A = 2*d1pow2A + 3*d1powA * d2powA + d2pow2A; B = 2*d3pow2A + 3*d3powA * d2powA + d2pow2A; N = 3*d1powA * (d1powA + d2powA); if (N > 0) {N = 1 / N;} M = 3*d3powA * (d3powA + d2powA); if (M > 0) {M = 1 / M;} bp1 = { x: ((-d2pow2A * p0.x + A*p1.x + d1pow2A * p2.x) * N), y: ((-d2pow2A * p0.y + A*p1.y + d1pow2A * p2.y) * N)}; bp2 = { x: (( d3pow2A * p1.x + B*p2.x - d2pow2A * p3.x) * M), y: (( d3pow2A * p1.y + B*p2.y - d2pow2A * p3.y) * M)}; if (bp1.x == 0 && bp1.y == 0) {bp1 = p1;} if (bp2.x == 0 && bp2.y == 0) {bp2 = p2;} d += "C" + bp1.x + "," + bp1.y + " " + bp2.x + "," + bp2.y + " " + p2.x + "," + p2.y + " "; } return d; } }; /** * this generates the SVG path for a linear drawing between datapoints. * @param data * @returns {string} * @private */ LineGraph.prototype._linear = function(data) { // linear var d = ""; for (var i = 0; i < data.length; i++) { if (i == 0) { d += data[i].x + "," + data[i].y; } else { d += " " + data[i].x + "," + data[i].y; } } return d; }; module.exports = LineGraph;