X-Git-Url: https://adrianiainlam.tk/git/?a=blobdiff_plain;f=dygraph-canvas.js;h=90d1b4eda04309310f6c4a4081b6c2cdfa4f42d1;hb=88e95c462340958bdfd0ac4c0736b94c5fd21024;hp=35e4662394d78e5da7a09c36330a284655615816;hpb=52c47e80f99af31a40e4f29624956b0c2a88b164;p=dygraphs.git diff --git a/dygraph-canvas.js b/dygraph-canvas.js index 35e4662..90d1b4e 100644 --- a/dygraph-canvas.js +++ b/dygraph-canvas.js @@ -1,311 +1,34 @@ -// Copyright 2006 Dan Vanderkam (danvdk@gmail.com) -// All Rights Reserved. +/** + * @license + * Copyright 2006 Dan Vanderkam (danvdk@gmail.com) + * MIT-licensed (http://opensource.org/licenses/MIT) + */ /** - * @fileoverview Based on PlotKit, but modified to meet the needs of dygraphs. + * @fileoverview Based on PlotKit.CanvasRenderer, but modified to meet the + * needs of dygraphs. + * * In particular, support for: * - grid overlays * - error bars * - dygraphs attribute system - * - * High level overview of classes: - * - * - DygraphLayout - * This contains all the data to be charted. - * It uses data coordinates, but also records the chart range (in data - * coordinates) and hence is able to calculate percentage positions ('In - * this view, Point A lies 25% down the x-axis.') - * Two things that it does not do are: - * 1. Record pixel coordinates for anything. - * 2. (oddly) determine anything about the layout of chart elements. - * The naming is a vestige of Dygraph's original PlotKit roots. - * - * - DygraphCanvasRenderer - * This class determines the charting area (in pixel coordinates), maps the - * percentage coordinates in the DygraphLayout to pixels and draws them. - * It's also responsible for creating chart DOM elements, i.e. annotations, - * tick mark labels, the title and the x/y-axis labels. - */ - -/** - * Creates a new DygraphLayout object. - * @param {Object} options Options for PlotKit.Layout - * @return {Object} The DygraphLayout object - */ -DygraphLayout = function(dygraph, options) { - this.dygraph_ = dygraph; - this.options = {}; // TODO(danvk): remove, use attr_ instead. - Dygraph.update(this.options, options ? options : {}); - this.datasets = new Array(); - this.annotations = new Array(); -}; - -DygraphLayout.prototype.attr_ = function(name) { - return this.dygraph_.attr_(name); -}; - -DygraphLayout.prototype.addDataset = function(setname, set_xy) { - this.datasets[setname] = set_xy; -}; - -DygraphLayout.prototype.setAnnotations = function(ann) { - // The Dygraph object's annotations aren't parsed. We parse them here and - // save a copy. If there is no parser, then the user must be using raw format. - this.annotations = []; - var parse = this.attr_('xValueParser') || function(x) { return x; }; - for (var i = 0; i < ann.length; i++) { - var a = {}; - if (!ann[i].xval && !ann[i].x) { - this.dygraph_.error("Annotations must have an 'x' property"); - return; - } - if (ann[i].icon && - !(ann[i].hasOwnProperty('width') && - ann[i].hasOwnProperty('height'))) { - this.dygraph_.error("Must set width and height when setting " + - "annotation.icon property"); - return; - } - Dygraph.update(a, ann[i]); - if (!a.xval) a.xval = parse(a.x); - this.annotations.push(a); - } -}; - -DygraphLayout.prototype.evaluate = function() { - this._evaluateLimits(); - this._evaluateLineCharts(); - this._evaluateLineTicks(); - this._evaluateAnnotations(); -}; - -DygraphLayout.prototype._evaluateLimits = function() { - this.minxval = this.maxxval = null; - if (this.options.dateWindow) { - this.minxval = this.options.dateWindow[0]; - this.maxxval = this.options.dateWindow[1]; - } else { - for (var name in this.datasets) { - if (!this.datasets.hasOwnProperty(name)) continue; - var series = this.datasets[name]; - if (series.length > 1) { - var x1 = series[0][0]; - if (!this.minxval || x1 < this.minxval) this.minxval = x1; - - var x2 = series[series.length - 1][0]; - if (!this.maxxval || x2 > this.maxxval) this.maxxval = x2; - } - } - } - this.xrange = this.maxxval - this.minxval; - this.xscale = (this.xrange != 0 ? 1/this.xrange : 1.0); - - for (var i = 0; i < this.options.yAxes.length; i++) { - var axis = this.options.yAxes[i]; - axis.minyval = axis.computedValueRange[0]; - axis.maxyval = axis.computedValueRange[1]; - axis.yrange = axis.maxyval - axis.minyval; - axis.yscale = (axis.yrange != 0 ? 1.0 / axis.yrange : 1.0); - - if (axis.g.attr_("logscale")) { - axis.ylogrange = Dygraph.log10(axis.maxyval) - Dygraph.log10(axis.minyval); - axis.ylogscale = (axis.ylogrange != 0 ? 1.0 / axis.ylogrange : 1.0); - if (!isFinite(axis.ylogrange) || isNaN(axis.ylogrange)) { - axis.g.error('axis ' + i + ' of graph at ' + axis.g + - ' can\'t be displayed in log scale for range [' + - axis.minyval + ' - ' + axis.maxyval + ']'); - } - } - } -}; - -DygraphLayout.prototype._evaluateLineCharts = function() { - // add all the rects - this.points = new Array(); - for (var setName in this.datasets) { - if (!this.datasets.hasOwnProperty(setName)) continue; - - var dataset = this.datasets[setName]; - var axis = this.options.yAxes[this.options.seriesToAxisMap[setName]]; - - for (var j = 0; j < dataset.length; j++) { - var item = dataset[j]; - - var yval; - if (axis.logscale) { - yval = 1.0 - ((Dygraph.log10(parseFloat(item[1])) - Dygraph.log10(axis.minyval)) * axis.ylogscale); // really should just be yscale. - } else { - yval = 1.0 - ((parseFloat(item[1]) - axis.minyval) * axis.yscale); - } - var point = { - // TODO(danvk): here - x: ((parseFloat(item[0]) - this.minxval) * this.xscale), - y: yval, - xval: parseFloat(item[0]), - yval: parseFloat(item[1]), - name: setName - }; - - this.points.push(point); - } - } -}; - -DygraphLayout.prototype._evaluateLineTicks = function() { - this.xticks = new Array(); - for (var i = 0; i < this.options.xTicks.length; i++) { - var tick = this.options.xTicks[i]; - var label = tick.label; - var pos = this.xscale * (tick.v - this.minxval); - if ((pos >= 0.0) && (pos <= 1.0)) { - this.xticks.push([pos, label]); - } - } - - this.yticks = new Array(); - for (var i = 0; i < this.options.yAxes.length; i++ ) { - var axis = this.options.yAxes[i]; - for (var j = 0; j < axis.ticks.length; j++) { - var tick = axis.ticks[j]; - var label = tick.label; - var pos = this.dygraph_.toPercentYCoord(tick.v, i); - if ((pos >= 0.0) && (pos <= 1.0)) { - this.yticks.push([i, pos, label]); - } - } - } -}; - - -/** - * Behaves the same way as PlotKit.Layout, but also copies the errors - * @private - */ -DygraphLayout.prototype.evaluateWithError = function() { - this.evaluate(); - if (!this.options.errorBars) return; - - // Copy over the error terms - var i = 0; // index in this.points - for (var setName in this.datasets) { - if (!this.datasets.hasOwnProperty(setName)) continue; - var j = 0; - var dataset = this.datasets[setName]; - for (var j = 0; j < dataset.length; j++, i++) { - var item = dataset[j]; - var xv = parseFloat(item[0]); - var yv = parseFloat(item[1]); - - if (xv == this.points[i].xval && - yv == this.points[i].yval) { - this.points[i].errorMinus = parseFloat(item[2]); - this.points[i].errorPlus = parseFloat(item[3]); - } - } - } -}; - -DygraphLayout.prototype._evaluateAnnotations = function() { - // Add the annotations to the point to which they belong. - // Make a map from (setName, xval) to annotation for quick lookups. - var annotations = {}; - for (var i = 0; i < this.annotations.length; i++) { - var a = this.annotations[i]; - annotations[a.xval + "," + a.series] = a; - } - - this.annotated_points = []; - for (var i = 0; i < this.points.length; i++) { - var p = this.points[i]; - var k = p.xval + "," + p.name; - if (k in annotations) { - p.annotation = annotations[k]; - this.annotated_points.push(p); - } - } -}; - -/** - * Convenience function to remove all the data sets from a graph - */ -DygraphLayout.prototype.removeAllDatasets = function() { - delete this.datasets; - this.datasets = new Array(); -}; - -/** - * Change the values of various layout options - * @param {Object} new_options an associative array of new properties */ -DygraphLayout.prototype.updateOptions = function(new_options) { - Dygraph.update(this.options, new_options ? new_options : {}); -}; /** - * Return a copy of the point at the indicated index, with its yval unstacked. - * @param int index of point in layout_.points - */ -DygraphLayout.prototype.unstackPointAtIndex = function(idx) { - var point = this.points[idx]; - - // Clone the point since we modify it - var unstackedPoint = {}; - for (var i in point) { - unstackedPoint[i] = point[i]; - } - - if (!this.attr_("stackedGraph")) { - return unstackedPoint; - } - - // The unstacked yval is equal to the current yval minus the yval of the - // next point at the same xval. - for (var i = idx+1; i < this.points.length; i++) { - if (this.points[i].xval == point.xval) { - unstackedPoint.yval -= this.points[i].yval; - break; - } - } - - return unstackedPoint; -} - -// Subclass PlotKit.CanvasRenderer to add: -// 1. X/Y grid overlay -// 2. Ability to draw error bars (if required) - -/** - * Sets some PlotKit.CanvasRenderer options + * The DygraphCanvasRenderer class does the actual rendering of the chart onto + * a canvas. It's based on PlotKit.CanvasRenderer. * @param {Object} element The canvas to attach to + * @param {Object} elementContext The 2d context of the canvas (injected so it + * can be mocked for testing.) * @param {Layout} layout The DygraphLayout object for this graph. - * @param {Object} options Options to pass on to CanvasRenderer + * @constructor */ -DygraphCanvasRenderer = function(dygraph, element, layout, options) { - // TODO(danvk): remove options, just use dygraph.attr_. +DygraphCanvasRenderer = function(dygraph, element, elementContext, layout) { this.dygraph_ = dygraph; - // default options - this.options = { - "strokeWidth": 0.5, - "drawXAxis": true, - "drawYAxis": true, - "axisLineColor": "black", - "axisLineWidth": 0.5, - "axisTickSize": 3, - "axisLabelColor": "black", - "axisLabelFont": "Arial", - "axisLabelFontSize": 9, - "axisLabelWidth": 50, - "drawYGrid": true, - "drawXGrid": true, - "gridLineColor": "rgb(128,128,128)", - "fillAlpha": 0.15, - "underlayCallback": null - }; - Dygraph.update(this.options, options); - this.layout = layout; this.element = element; + this.elementContext = elementContext; this.container = this.element.parentNode; this.height = this.element.height; @@ -321,20 +44,54 @@ DygraphCanvasRenderer = function(dygraph, element, layout, options) { this.annotations = new Array(); this.chartLabels = {}; - // TODO(danvk): consider all axes in this computation. - this.area = { + this.area = this.computeArea_(); + this.container.style.position = "relative"; + this.container.style.width = this.width + "px"; + + // Set up a clipping area for the canvas (and the interaction canvas). + // This ensures that we don't overdraw. + var ctx = this.dygraph_.canvas_ctx_; + ctx.beginPath(); + ctx.rect(this.area.x, this.area.y, this.area.w, this.area.h); + ctx.clip(); + + ctx = this.dygraph_.hidden_ctx_; + ctx.beginPath(); + ctx.rect(this.area.x, this.area.y, this.area.w, this.area.h); + ctx.clip(); +}; + +DygraphCanvasRenderer.prototype.attr_ = function(x) { + return this.dygraph_.attr_(x); +}; + +// Compute the box which the chart should be drawn in. This is the canvas's +// box, less space needed for axis and chart labels. +// TODO(danvk): this belongs in DygraphLayout. +DygraphCanvasRenderer.prototype.computeArea_ = function() { + var area = { // TODO(danvk): per-axis setting. - x: this.options.yAxisLabelWidth + 2 * this.options.axisTickSize, + x: 0, y: 0 }; - this.area.w = this.width - this.area.x - this.options.rightGap; - this.area.h = this.height - this.options.axisLabelFontSize - - 2 * this.options.axisTickSize; + if (this.attr_('drawYAxis')) { + area.x = this.attr_('yAxisLabelWidth') + 2 * this.attr_('axisTickSize'); + } + + area.w = this.width - area.x - this.attr_('rightGap'); + area.h = this.height; + if (this.attr_('drawXAxis')) { + if (this.attr_('xAxisHeight')) { + area.h -= this.attr_('xAxisHeight'); + } else { + area.h -= this.attr_('axisLabelFontSize') + 2 * this.attr_('axisTickSize'); + } + } // Shrink the drawing area to accomodate additional y-axes. if (this.dygraph_.numAxes() == 2) { // TODO(danvk): per-axis setting. - this.area.w -= (this.options.yAxisLabelWidth + 2 * this.options.axisTickSize); + area.w -= (this.attr_('yAxisLabelWidth') + 2 * this.attr_('axisTickSize')); } else if (this.dygraph_.numAxes() > 2) { this.dygraph_.error("Only two y-axes are supported at this time. (Trying " + "to use " + this.dygraph_.numAxes() + ")"); @@ -342,11 +99,11 @@ DygraphCanvasRenderer = function(dygraph, element, layout, options) { // Add space for chart labels: title, xlabel and ylabel. if (this.attr_('title')) { - this.area.h -= this.attr_('titleHeight'); - this.area.y += this.attr_('titleHeight'); + area.h -= this.attr_('titleHeight'); + area.y += this.attr_('titleHeight'); } if (this.attr_('xlabel')) { - this.area.h -= this.attr_('xLabelHeight'); + area.h -= this.attr_('xLabelHeight'); } if (this.attr_('ylabel')) { // It would make sense to shift the chart here to make room for the y-axis @@ -355,24 +112,7 @@ DygraphCanvasRenderer = function(dygraph, element, layout, options) { // doesn't, the yAxisLabelWidth option can be increased. } - this.container.style.position = "relative"; - this.container.style.width = this.width + "px"; - - // Set up a clipping area for the canvas (and the interaction canvas). - // This ensures that we don't overdraw. - var ctx = this.dygraph_.canvas_.getContext("2d"); - ctx.beginPath(); - ctx.rect(this.area.x, this.area.y, this.area.w, this.area.h); - ctx.clip(); - - ctx = this.dygraph_.hidden_.getContext("2d"); - ctx.beginPath(); - ctx.rect(this.area.x, this.area.y, this.area.w, this.area.h); - ctx.clip(); -}; - -DygraphCanvasRenderer.prototype.attr_ = function(x) { - return this.dygraph_.attr_(x); + return area; }; DygraphCanvasRenderer.prototype.clear = function() { @@ -383,7 +123,7 @@ DygraphCanvasRenderer.prototype.clear = function() { this.clearDelay.cancel(); this.clearDelay = null; } - var context = this.element.getContext("2d"); + var context = this.elementContext; } catch (e) { // TODO(danvk): this is broken, since MochiKit.Async is gone. @@ -393,7 +133,7 @@ DygraphCanvasRenderer.prototype.clear = function() { } } - var context = this.element.getContext("2d"); + var context = this.elementContext; context.clearRect(0, 0, this.width, this.height); for (var i = 0; i < this.xlabels.length; i++) { @@ -440,26 +180,34 @@ DygraphCanvasRenderer.isSupported = function(canvasName) { }; /** + * @param { [String] } colors Array of color strings. Should have one entry for + * each series to be rendered. + */ +DygraphCanvasRenderer.prototype.setColors = function(colors) { + this.colorScheme_ = colors; +}; + +/** * Draw an X/Y grid on top of the existing plot */ DygraphCanvasRenderer.prototype.render = function() { // Draw the new X/Y grid. Lines appear crisper when pixels are rounded to // half-integers. This prevents them from drawing in two rows/cols. - var ctx = this.element.getContext("2d"); + var ctx = this.elementContext; function halfUp(x){return Math.round(x)+0.5}; function halfDown(y){return Math.round(y)-0.5}; - if (this.options.underlayCallback) { + if (this.attr_('underlayCallback')) { // NOTE: we pass the dygraph object to this callback twice to avoid breaking // users who expect a deprecated form of this callback. - this.options.underlayCallback(ctx, this.area, this.dygraph_, this.dygraph_); + this.attr_('underlayCallback')(ctx, this.area, this.dygraph_, this.dygraph_); } - if (this.options.drawYGrid) { + if (this.attr_('drawYGrid')) { var ticks = this.layout.yticks; ctx.save(); - ctx.strokeStyle = this.options.gridLineColor; - ctx.lineWidth = this.options.axisLineWidth; + ctx.strokeStyle = this.attr_('gridLineColor'); + ctx.lineWidth = this.attr_('gridLineWidth'); for (var i = 0; i < ticks.length; i++) { // TODO(danvk): allow secondary axes to draw a grid, too. if (ticks[i][0] != 0) continue; @@ -473,11 +221,11 @@ DygraphCanvasRenderer.prototype.render = function() { } } - if (this.options.drawXGrid) { + if (this.attr_('drawXGrid')) { var ticks = this.layout.xticks; ctx.save(); - ctx.strokeStyle = this.options.gridLineColor; - ctx.lineWidth = this.options.axisLineWidth; + ctx.strokeStyle = this.attr_('gridLineColor'); + ctx.lineWidth = this.attr_('gridLineWidth'); for (var i=0; i 0) { + var num_axes = this.dygraph_.numAxes(); for (var i = 0; i < this.layout.yticks.length; i++) { var tick = this.layout.yticks[i]; if (typeof(tick) == "function") return; var x = this.area.x; var sgn = 1; + var prec_axis = 'y1'; if (tick[0] == 1) { // right-side y-axis x = this.area.x + this.area.w; sgn = -1; + prec_axis = 'y2'; } var y = this.area.y + tick[1] * this.area.h; context.beginPath(); context.moveTo(halfUp(x), halfDown(y)); - context.lineTo(halfUp(x - sgn * this.options.axisTickSize), halfDown(y)); + context.lineTo(halfUp(x - sgn * this.attr_('axisTickSize')), halfDown(y)); context.closePath(); context.stroke(); - var label = makeDiv(tick[2]); - var top = (y - this.options.axisLabelFontSize / 2); + var label = makeDiv(tick[2], 'y', num_axes == 2 ? prec_axis : null); + var top = (y - this.attr_('axisLabelFontSize') / 2); if (top < 0) top = 0; - if (top + this.options.axisLabelFontSize + 3 > this.height) { + if (top + this.attr_('axisLabelFontSize') + 3 > this.height) { label.style.bottom = "0px"; } else { label.style.top = top + "px"; } if (tick[0] == 0) { - label.style.left = (this.area.x - this.options.yAxisLabelWidth - this.options.axisTickSize) + "px"; + label.style.left = (this.area.x - this.attr_('yAxisLabelWidth') - this.attr_('axisTickSize')) + "px"; label.style.textAlign = "right"; } else if (tick[0] == 1) { label.style.left = (this.area.x + this.area.w + - this.options.axisTickSize) + "px"; + this.attr_('axisTickSize')) + "px"; label.style.textAlign = "left"; } - label.style.width = this.options.yAxisLabelWidth + "px"; + label.style.width = this.attr_('yAxisLabelWidth') + "px"; this.container.appendChild(label); this.ylabels.push(label); } @@ -575,7 +331,7 @@ DygraphCanvasRenderer.prototype._renderAxis = function() { // tick on the x-axis. Shift the bottom tick up a little bit to // compensate if necessary. var bottomTick = this.ylabels[0]; - var fontSize = this.options.axisLabelFontSize; + var fontSize = this.attr_('axisLabelFontSize'); var bottom = parseInt(bottomTick.style.top) + fontSize; if (bottom > this.height - fontSize) { bottomTick.style.top = (parseInt(bottomTick.style.top) - @@ -600,7 +356,7 @@ DygraphCanvasRenderer.prototype._renderAxis = function() { } } - if (this.options.drawXAxis) { + if (this.attr_('drawXAxis')) { if (this.layout.xticks) { for (var i = 0; i < this.layout.xticks.length; i++) { var tick = this.layout.xticks[i]; @@ -610,17 +366,17 @@ DygraphCanvasRenderer.prototype._renderAxis = function() { var y = this.area.y + this.area.h; context.beginPath(); context.moveTo(halfUp(x), halfDown(y)); - context.lineTo(halfUp(x), halfDown(y + this.options.axisTickSize)); + context.lineTo(halfUp(x), halfDown(y + this.attr_('axisTickSize'))); context.closePath(); context.stroke(); - var label = makeDiv(tick[1]); + var label = makeDiv(tick[1], 'x'); label.style.textAlign = "center"; - label.style.top = (y + this.options.axisTickSize) + 'px'; + label.style.top = (y + this.attr_('axisTickSize')) + 'px'; - var left = (x - this.options.axisLabelWidth/2); - if (left + this.options.axisLabelWidth > this.width) { - left = this.width - this.options.xAxisLabelWidth; + var left = (x - this.attr_('axisLabelWidth')/2); + if (left + this.attr_('axisLabelWidth') > this.width) { + left = this.width - this.attr_('xAxisLabelWidth'); label.style.textAlign = "right"; } if (left < 0) { @@ -629,7 +385,7 @@ DygraphCanvasRenderer.prototype._renderAxis = function() { } label.style.left = left + "px"; - label.style.width = this.options.xAxisLabelWidth + "px"; + label.style.width = this.attr_('xAxisLabelWidth') + "px"; this.container.appendChild(label); this.xlabels.push(label); } @@ -658,7 +414,7 @@ DygraphCanvasRenderer.prototype._renderChartLabels = function() { div.style.width = this.area.w + 'px'; div.style.height = this.attr_('titleHeight') + 'px'; div.style.textAlign = 'center'; - div.style.fontSize = (this.attr_('titleHeight') - 2) + 'px'; + div.style.fontSize = (this.attr_('titleHeight') - 8) + 'px'; div.style.fontWeight = 'bold'; var class_div = document.createElement("div"); class_div.className = 'dygraph-label dygraph-title'; @@ -709,14 +465,25 @@ DygraphCanvasRenderer.prototype._renderChartLabels = function() { inner_div.style.top = (box.height / 2 - box.width / 2) + 'px'; inner_div.style.left = (box.width / 2 - box.height / 2) + 'px'; inner_div.style.textAlign = 'center'; + + // CSS rotation is an HTML5 feature which is not standardized. Hence every + // browser has its own name for the CSS style. inner_div.style.transform = 'rotate(-90deg)'; // HTML5 inner_div.style.WebkitTransform = 'rotate(-90deg)'; // Safari/Chrome inner_div.style.MozTransform = 'rotate(-90deg)'; // Firefox inner_div.style.OTransform = 'rotate(-90deg)'; // Opera inner_div.style.msTransform = 'rotate(-90deg)'; // IE9 - inner_div.id = 'foo'; // XXX - // inner_div.style.filter = - // 'progid:DXImageTransform.Microsoft.BasicImage(rotation=3)'; + + if (typeof(document.documentMode) !== 'undefined' && + document.documentMode < 9) { + // We're dealing w/ an old version of IE, so we have to rotate the text + // using a BasicImage transform. This uses a different origin of rotation + // than HTML5 rotation (top left of div vs. its center). + inner_div.style.filter = + 'progid:DXImageTransform.Microsoft.BasicImage(rotation=3)'; + inner_div.style.left = '0px'; + inner_div.style.top = '0px'; + } var class_div = document.createElement("div"); class_div.className = 'dygraph-label dygraph-ylabel'; @@ -733,7 +500,7 @@ DygraphCanvasRenderer.prototype._renderChartLabels = function() { DygraphCanvasRenderer.prototype._renderAnnotations = function() { var annotationStyle = { "position": "absolute", - "fontSize": this.options.axisLabelFontSize + "px", + "fontSize": this.attr_('axisLabelFontSize') + "px", "zIndex": 10, "overflow": "hidden" }; @@ -812,7 +579,7 @@ DygraphCanvasRenderer.prototype._renderAnnotations = function() { this.container.appendChild(div); this.annotations.push(div); - var ctx = this.element.getContext("2d"); + var ctx = this.elementContext; ctx.strokeStyle = this.colors[p.name]; ctx.beginPath(); if (!a.attachAtBottom) { @@ -832,15 +599,19 @@ DygraphCanvasRenderer.prototype._renderAnnotations = function() { * Overrides the CanvasRenderer method to draw error bars */ DygraphCanvasRenderer.prototype._renderLineChart = function() { + var isNullOrNaN = function(x) { + return (x === null || isNaN(x)); + }; + // TODO(danvk): use this.attr_ for many of these. - var context = this.element.getContext("2d"); - var colorCount = this.options.colorScheme.length; - var colorScheme = this.options.colorScheme; - var fillAlpha = this.options.fillAlpha; - var errorBars = this.layout.options.errorBars; + var context = this.elementContext; + var fillAlpha = this.attr_('fillAlpha'); + var errorBars = this.attr_("errorBars") || this.attr_("customBars"); var fillGraph = this.attr_("fillGraph"); - var stackedGraph = this.layout.options.stackedGraph; - var stepPlot = this.layout.options.stepPlot; + var stackedGraph = this.attr_("stackedGraph"); + var stepPlot = this.attr_("stepPlot"); + var points = this.layout.points; + var pointsLength = points.length; var setNames = []; for (var name in this.layout.datasets) { @@ -850,15 +621,16 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() { } var setCount = setNames.length; + // TODO(danvk): Move this mapping into Dygraph and get it out of here. this.colors = {} for (var i = 0; i < setCount; i++) { - this.colors[setNames[i]] = colorScheme[i % colorCount]; + this.colors[setNames[i]] = this.colorScheme_[i % this.colorScheme_.length]; } // Update Points // TODO(danvk): here - for (var i = 0; i < this.layout.points.length; i++) { - var point = this.layout.points[i]; + for (var i = pointsLength; i--;) { + var point = points[i]; point.canvasx = this.area.w * point.x + this.area.x; point.canvasy = this.area.h * point.y + this.area.y; } @@ -872,8 +644,7 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() { for (var i = 0; i < setCount; i++) { var setName = setNames[i]; - var axis = this.layout.options.yAxes[ - this.layout.options.seriesToAxisMap[setName]]; + var axis = this.dygraph_.axisPropertiesForSeries(setName); var color = this.colors[setName]; // setup graphics context @@ -888,8 +659,8 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() { fillAlpha + ')'; ctx.fillStyle = err_color; ctx.beginPath(); - for (var j = 0; j < this.layout.points.length; j++) { - var point = this.layout.points[j]; + for (var j = 0; j < pointsLength; j++) { + var point = points[j]; if (point.name == setName) { if (!Dygraph.isOK(point.y)) { prevX = NaN; @@ -898,12 +669,10 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() { // TODO(danvk): here if (stepPlot) { - var newYs = [ prevY - point.errorPlus * yscale, - prevY + point.errorMinus * yscale ]; + var newYs = [ point.y_bottom, point.y_top ]; prevY = point.y; } else { - var newYs = [ point.y - point.errorPlus * yscale, - point.y + point.errorMinus * yscale ]; + var newYs = [ point.y_bottom, point.y_top ]; } newYs[0] = this.area.h * newYs[0] + this.area.y; newYs[1] = this.area.h * newYs[1] + this.area.y; @@ -935,8 +704,7 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() { for (var i = setCount - 1; i >= 0; i--) { var setName = setNames[i]; var color = this.colors[setName]; - var axis = this.layout.options.yAxes[ - this.layout.options.seriesToAxisMap[setName]]; + var axis = this.dygraph_.axisPropertiesForSeries(setName); var axisY = 1.0 + axis.minyval * axis.yscale; if (axisY < 0.0) axisY = 0.0; else if (axisY > 1.0) axisY = 1.0; @@ -953,8 +721,8 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() { fillAlpha + ')'; ctx.fillStyle = err_color; ctx.beginPath(); - for (var j = 0; j < this.layout.points.length; j++) { - var point = this.layout.points[j]; + for (var j = 0; j < pointsLength; j++) { + var point = points[j]; if (point.name == setName) { if (!Dygraph.isOK(point.y)) { prevX = NaN; @@ -988,69 +756,78 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() { } } - for (var i = 0; i < setCount; i++) { + // Drawing the lines. + var firstIndexInSet = 0; + var afterLastIndexInSet = 0; + var setLength = 0; + for (var i = 0; i < setCount; i += 1) { + setLength = this.layout.setPointsLengths[i]; + afterLastIndexInSet += setLength; var setName = setNames[i]; var color = this.colors[setName]; var strokeWidth = this.dygraph_.attr_("strokeWidth", setName); // setup graphics context context.save(); - var point = this.layout.points[0]; var pointSize = this.dygraph_.attr_("pointSize", setName); var prevX = null, prevY = null; var drawPoints = this.dygraph_.attr_("drawPoints", setName); - var points = this.layout.points; - for (var j = 0; j < points.length; j++) { + for (var j = firstIndexInSet; j < afterLastIndexInSet; j++) { var point = points[j]; - if (point.name == setName) { - if (!Dygraph.isOK(point.canvasy)) { - if (stepPlot && prevX != null) { - // Draw a horizontal line to the start of the missing data + if (isNullOrNaN(point.canvasy)) { + if (stepPlot && prevX != null) { + // Draw a horizontal line to the start of the missing data + ctx.beginPath(); + ctx.strokeStyle = color; + ctx.lineWidth = this.attr_('strokeWidth'); + ctx.moveTo(prevX, prevY); + ctx.lineTo(point.canvasx, prevY); + ctx.stroke(); + } + // this will make us move to the next point, not draw a line to it. + prevX = prevY = null; + } else { + // A point is "isolated" if it is non-null but both the previous + // and next points are null. + var isIsolated = (!prevX && (j == points.length - 1 || + isNullOrNaN(points[j+1].canvasy))); + if (prevX === null) { + prevX = point.canvasx; + prevY = point.canvasy; + } else { + // Skip over points that will be drawn in the same pixel. + if (Math.round(prevX) == Math.round(point.canvasx) && + Math.round(prevY) == Math.round(point.canvasy)) { + continue; + } + // TODO(antrob): skip over points that lie on a line that is already + // going to be drawn. There is no need to have more than 2 + // consecutive points that are collinear. + if (strokeWidth) { ctx.beginPath(); ctx.strokeStyle = color; - ctx.lineWidth = this.options.strokeWidth; + ctx.lineWidth = strokeWidth; ctx.moveTo(prevX, prevY); - ctx.lineTo(point.canvasx, prevY); - ctx.stroke(); - } - // this will make us move to the next point, not draw a line to it. - prevX = prevY = null; - } else { - // A point is "isolated" if it is non-null but both the previous - // and next points are null. - var isIsolated = (!prevX && (j == points.length - 1 || - !Dygraph.isOK(points[j+1].canvasy))); - - if (!prevX) { + if (stepPlot) { + ctx.lineTo(point.canvasx, prevY); + } prevX = point.canvasx; prevY = point.canvasy; - } else { - // TODO(danvk): figure out why this conditional is necessary. - if (strokeWidth) { - ctx.beginPath(); - ctx.strokeStyle = color; - ctx.lineWidth = strokeWidth; - ctx.moveTo(prevX, prevY); - if (stepPlot) { - ctx.lineTo(point.canvasx, prevY); - } - prevX = point.canvasx; - prevY = point.canvasy; - ctx.lineTo(prevX, prevY); - ctx.stroke(); - } + ctx.lineTo(prevX, prevY); + ctx.stroke(); } + } - if (drawPoints || isIsolated) { - ctx.beginPath(); - ctx.fillStyle = color; - ctx.arc(point.canvasx, point.canvasy, pointSize, - 0, 2 * Math.PI, false); - ctx.fill(); - } + if (drawPoints || isIsolated) { + ctx.beginPath(); + ctx.fillStyle = color; + ctx.arc(point.canvasx, point.canvasy, pointSize, + 0, 2 * Math.PI, false); + ctx.fill(); } } } + firstIndexInSet = afterLastIndexInSet; } context.restore();