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) {
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]);
}
}
}
};
/**
* 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);
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]];
if (group.visible == true) {
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
if (groupData.length > 0) {
preprocessedGroup = this._preprocessData(groupData, group);
groupRanges.push({min: preprocessedGroup.min, max: preprocessedGroup.max});
preprocessedGroupData.push(preprocessedGroup.data);
}
else {
groupRanges.push({});
preprocessedGroupData.push([]);
}
}
else {
groupRanges.push({});
preprocessedGroupData.push([]);
}
}
// 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.visible == true) {
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.visible == true) {
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;}
else {this.yAxisLeft.lineOffset = 0;}
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;