X-Git-Url: https://adrianiainlam.tk/git/?a=blobdiff_plain;f=dygraph-canvas.js;h=23e93a81a21643e73fc555a184ec88e5ec6a9a7e;hb=c9093b7b3b9cfd2471dff93b8df9cbe1e84a8448;hp=04e1eb11bbb94f7060b12feed6fc1260b3d94ab7;hpb=6a1aa64f6d22473e0357ad1cd7bd93259d899a69;p=dygraphs.git diff --git a/dygraph-canvas.js b/dygraph-canvas.js index 04e1eb1..ff291e5 100644 --- a/dygraph-canvas.js +++ b/dygraph-canvas.js @@ -1,230 +1,1082 @@ -// Copyright 2006 Dan Vanderkam (danvdk@gmail.com) -// All Rights Reserved. - /** - * @fileoverview Subclasses various parts of PlotKit to meet the additional - * needs of DateGraph: grid overlays and error bars + * @license + * Copyright 2006 Dan Vanderkam (danvdk@gmail.com) + * MIT-licensed (http://opensource.org/licenses/MIT) */ -// Subclass PlotKit.Layout to add: -// 1. Sigma/errorBars properties -// 2. Copy error terms for PlotKit.CanvasRenderer._renderLineChart - /** - * Creates a new DateGraphLayout object. Options are the same as those allowed - * by the PlotKit.Layout constructor. - * @param {Object} options Options for PlotKit.Layout - * @return {Object} The DateGraphLayout object + * @fileoverview Based on PlotKit.CanvasRenderer, but modified to meet the + * needs of dygraphs. + * + * In particular, support for: + * - grid overlays + * - error bars + * - dygraphs attribute system */ -DateGraphLayout = function(options) { - PlotKit.Layout.call(this, "line", options); -}; -DateGraphLayout.prototype = new PlotKit.Layout(); /** - * Behaves the same way as PlotKit.Layout, but also copies the errors - * @private + * 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. + * @constructor */ -DateGraphLayout.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) { - var j = 0; - var dataset = this.datasets[setName]; - if (PlotKit.Base.isFuncLike(dataset)) continue; - 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]); - } + +/*jshint globalstrict: true */ +/*global Dygraph:false,RGBColor:false */ +"use strict"; + + +var DygraphCanvasRenderer = function(dygraph, element, elementContext, layout) { + this.dygraph_ = dygraph; + + this.layout = layout; + this.element = element; + this.elementContext = elementContext; + this.container = this.element.parentNode; + + this.height = this.element.height; + this.width = this.element.width; + + // --- check whether everything is ok before we return + if (!this.isIE && !(DygraphCanvasRenderer.isSupported(this.element))) + throw "Canvas is not supported."; + + // internal state + this.xlabels = []; + this.ylabels = []; + this.annotations = []; + this.chartLabels = {}; + + this.area = layout.getPlotArea(); + 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. + if (this.dygraph_.isUsingExcanvas_) { + this._createIEClipArea(); + } else { + // on Android 3 and 4, setting a clipping area on a canvas prevents it from + // displaying anything. + if (!Dygraph.isAndroid()) { + 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(); } } }; -/** - * Convenience function to remove all the data sets from a graph - */ -DateGraphLayout.prototype.removeAllDatasets = function() { - delete this.datasets; - this.datasets = new Array(); +DygraphCanvasRenderer.prototype.attr_ = function(x) { + return this.dygraph_.attr_(x); }; -/** - * Change the values of various layout options - * @param {Object} new_options an associative array of new properties - */ -DateGraphLayout.prototype.updateOptions = function(new_options) { - MochiKit.Base.update(this.options, new_options ? new_options : {}); +DygraphCanvasRenderer.prototype.clear = function() { + var context; + if (this.isIE) { + // VML takes a while to start up, so we just poll every this.IEDelay + try { + if (this.clearDelay) { + this.clearDelay.cancel(); + this.clearDelay = null; + } + context = this.elementContext; + } + catch (e) { + // TODO(danvk): this is broken, since MochiKit.Async is gone. + // this.clearDelay = MochiKit.Async.wait(this.IEDelay); + // this.clearDelay.addCallback(bind(this.clear, this)); + return; + } + } + + context = this.elementContext; + context.clearRect(0, 0, this.width, this.height); + + function removeArray(ary) { + for (var i = 0; i < ary.length; i++) { + var el = ary[i]; + if (el.parentNode) el.parentNode.removeChild(el); + } + } + + removeArray(this.xlabels); + removeArray(this.ylabels); + removeArray(this.annotations); + + for (var k in this.chartLabels) { + if (!this.chartLabels.hasOwnProperty(k)) continue; + var el = this.chartLabels[k]; + if (el.parentNode) el.parentNode.removeChild(el); + } + this.xlabels = []; + this.ylabels = []; + this.annotations = []; + this.chartLabels = {}; }; -// Subclass PlotKit.CanvasRenderer to add: -// 1. X/Y grid overlay -// 2. Ability to draw error bars (if required) + +DygraphCanvasRenderer.isSupported = function(canvasName) { + var canvas = null; + try { + if (typeof(canvasName) == 'undefined' || canvasName === null) { + canvas = document.createElement("canvas"); + } else { + canvas = canvasName; + } + canvas.getContext("2d"); + } + catch (e) { + var ie = navigator.appVersion.match(/MSIE (\d\.\d)/); + var opera = (navigator.userAgent.toLowerCase().indexOf("opera") != -1); + if ((!ie) || (ie[1] < 6) || (opera)) + return false; + return true; + } + return true; +}; /** - * Sets some PlotKit.CanvasRenderer options - * @param {Object} element The canvas to attach to - * @param {Layout} layout The DateGraphLayout object for this graph. - * @param {Object} options Options to pass on to CanvasRenderer + * @param { [String] } colors Array of color strings. Should have one entry for + * each series to be rendered. */ -DateGraphCanvasRenderer = function(element, layout, options) { - PlotKit.CanvasRenderer.call(this, element, layout, options); - this.options.shouldFill = false; - this.options.shouldStroke = true; - this.options.drawYGrid = true; - this.options.drawXGrid = true; - this.options.gridLineColor = MochiKit.Color.Color.grayColor(); - MochiKit.Base.update(this.options, options); - - // TODO(danvk) This shouldn't be necessary: effects should be overlaid - this.options.drawBackground = false; +DygraphCanvasRenderer.prototype.setColors = function(colors) { + this.colorScheme_ = colors; }; -DateGraphCanvasRenderer.prototype = new PlotKit.CanvasRenderer(); /** * Draw an X/Y grid on top of the existing plot */ -DateGraphCanvasRenderer.prototype.render = function() { - // Do the ordinary rendering, as before - // TODO(danvk) Call super.render() - this._renderLineChart(); - this._renderLineAxis(); +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.elementContext; + function halfUp(x) { return Math.round(x) + 0.5; } + function halfDown(y){ return Math.round(y) - 0.5; } + + 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.attr_('underlayCallback')(ctx, this.area, this.dygraph_, this.dygraph_); + } - // Draw the new X/Y grid - var ctx = this.element.getContext("2d"); - if (this.options.drawYGrid) { - var ticks = this.layout.yticks; + var x, y, i, ticks; + if (this.attr_('drawYGrid')) { + ticks = this.layout.yticks; + // TODO(konigsberg): I don't think these calls to save() have a corresponding restore(). ctx.save(); - ctx.strokeStyle = this.options.gridLineColor.toRGBString(); - ctx.lineWidth = this.options.axisLineWidth; - for (var i = 0; i < ticks.length; i++) { - var x = this.area.x; - var y = this.area.y + ticks[i][0] * this.area.h; + ctx.strokeStyle = this.attr_('gridLineColor'); + ctx.lineWidth = this.attr_('gridLineWidth'); + for (i = 0; i < ticks.length; i++) { + // TODO(danvk): allow secondary axes to draw a grid, too. + if (ticks[i][0] !== 0) continue; + x = halfUp(this.area.x); + y = halfDown(this.area.y + ticks[i][1] * this.area.h); ctx.beginPath(); ctx.moveTo(x, y); ctx.lineTo(x + this.area.w, y); ctx.closePath(); ctx.stroke(); } + ctx.restore(); } - if (this.options.drawXGrid) { - var ticks = this.layout.xticks; + if (this.attr_('drawXGrid')) { + ticks = this.layout.xticks; ctx.save(); - ctx.strokeStyle = this.options.gridLineColor.toRGBString(); - ctx.lineWidth = this.options.axisLineWidth; - for (var i=0; i= 0; i--) { + if (graphDiv.childNodes[i].className == className) { + graphDiv.removeChild(graphDiv.childNodes[i]); + } + } + + // Determine background color to give clip divs. + var backgroundColor = document.bgColor; + var element = this.dygraph_.graphDiv; + while (element != document) { + var bgcolor = element.currentStyle.backgroundColor; + if (bgcolor && bgcolor != 'transparent') { + backgroundColor = bgcolor; + break; + } + element = element.parentNode; + } + + function createClipDiv(area) { + if (area.w === 0 || area.h === 0) { + return; + } + var elem = document.createElement('div'); + elem.className = className; + elem.style.backgroundColor = backgroundColor; + elem.style.position = 'absolute'; + elem.style.left = area.x + 'px'; + elem.style.top = area.y + 'px'; + elem.style.width = area.w + 'px'; + elem.style.height = area.h + 'px'; + graphDiv.appendChild(elem); + } + + var plotArea = this.area; + // Left side + createClipDiv({ + x:0, y:0, + w:plotArea.x, + h:this.height + }); + + // Top + createClipDiv({ + x: plotArea.x, y: 0, + w: this.width - plotArea.x, + h: plotArea.y + }); + + // Right side + createClipDiv({ + x: plotArea.x + plotArea.w, y: 0, + w: this.width-plotArea.x - plotArea.w, + h: this.height + }); + + // Bottom + createClipDiv({ + x: plotArea.x, + y: plotArea.y + plotArea.h, + w: this.width - plotArea.x, + h: this.height - plotArea.h - plotArea.y + }); +}; + +DygraphCanvasRenderer.prototype._renderAxis = function() { + if (!this.attr_('drawXAxis') && !this.attr_('drawYAxis')) return; + + // Round pixels to half-integer boundaries for crisper drawing. + function halfUp(x) { return Math.round(x) + 0.5; } + function halfDown(y){ return Math.round(y) - 0.5; } + + var context = this.elementContext; + + var label, x, y, tick, i; + + var labelStyle = { + position: "absolute", + fontSize: this.attr_('axisLabelFontSize') + "px", + zIndex: 10, + color: this.attr_('axisLabelColor'), + width: this.attr_('axisLabelWidth') + "px", + // height: this.attr_('axisLabelFontSize') + 2 + "px", + lineHeight: "normal", // Something other than "normal" line-height screws up label positioning. + overflow: "hidden" + }; + var makeDiv = function(txt, axis, prec_axis) { + var div = document.createElement("div"); + for (var name in labelStyle) { + if (labelStyle.hasOwnProperty(name)) { + div.style[name] = labelStyle[name]; + } + } + var inner_div = document.createElement("div"); + inner_div.className = 'dygraph-axis-label' + + ' dygraph-axis-label-' + axis + + (prec_axis ? ' dygraph-axis-label-' + prec_axis : ''); + inner_div.innerHTML=txt; + div.appendChild(inner_div); + return div; + }; + + // axis lines + context.save(); + context.strokeStyle = this.attr_('axisLineColor'); + context.lineWidth = this.attr_('axisLineWidth'); + + if (this.attr_('drawYAxis')) { + if (this.layout.yticks && this.layout.yticks.length > 0) { + var num_axes = this.dygraph_.numAxes(); + for (i = 0; i < this.layout.yticks.length; i++) { + tick = this.layout.yticks[i]; + if (typeof(tick) == "function") return; + 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'; + } + y = this.area.y + tick[1] * this.area.h; + + /* Tick marks are currently clipped, so don't bother drawing them. + context.beginPath(); + context.moveTo(halfUp(x), halfDown(y)); + context.lineTo(halfUp(x - sgn * this.attr_('axisTickSize')), halfDown(y)); + context.closePath(); + context.stroke(); + */ + + 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.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.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.attr_('axisTickSize')) + "px"; + label.style.textAlign = "left"; + } + label.style.width = this.attr_('yAxisLabelWidth') + "px"; + this.container.appendChild(label); + this.ylabels.push(label); + } + + // The lowest tick on the y-axis often overlaps with the leftmost + // 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.attr_('axisLabelFontSize'); + var bottom = parseInt(bottomTick.style.top, 10) + fontSize; + if (bottom > this.height - fontSize) { + bottomTick.style.top = (parseInt(bottomTick.style.top, 10) - + fontSize / 2) + "px"; + } + } + + // draw a vertical line on the left to separate the chart from the labels. + context.beginPath(); + context.moveTo(halfUp(this.area.x), halfDown(this.area.y)); + context.lineTo(halfUp(this.area.x), halfDown(this.area.y + this.area.h)); + context.closePath(); + context.stroke(); + + // if there's a secondary y-axis, draw a vertical line for that, too. + if (this.dygraph_.numAxes() == 2) { + context.beginPath(); + context.moveTo(halfDown(this.area.x + this.area.w), halfDown(this.area.y)); + context.lineTo(halfDown(this.area.x + this.area.w), halfDown(this.area.y + this.area.h)); + context.closePath(); + context.stroke(); + } + } + + if (this.attr_('drawXAxis')) { + if (this.layout.xticks) { + for (i = 0; i < this.layout.xticks.length; i++) { + tick = this.layout.xticks[i]; + x = this.area.x + tick[0] * this.area.w; + y = this.area.y + this.area.h; + + /* Tick marks are currently clipped, so don't bother drawing them. + context.beginPath(); + context.moveTo(halfUp(x), halfDown(y)); + context.lineTo(halfUp(x), halfDown(y + this.attr_('axisTickSize'))); + context.closePath(); + context.stroke(); + */ + + label = makeDiv(tick[1], 'x'); + label.style.textAlign = "center"; + label.style.top = (y + this.attr_('axisTickSize')) + 'px'; + + 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) { + left = 0; + label.style.textAlign = "left"; + } + + label.style.left = left + "px"; + label.style.width = this.attr_('xAxisLabelWidth') + "px"; + this.container.appendChild(label); + this.xlabels.push(label); + } + } + + context.beginPath(); + context.moveTo(halfUp(this.area.x), halfDown(this.area.y + this.area.h)); + context.lineTo(halfUp(this.area.x + this.area.w), halfDown(this.area.y + this.area.h)); + context.closePath(); + context.stroke(); + } + + context.restore(); +}; + + +DygraphCanvasRenderer.prototype._renderChartLabels = function() { + var div, class_div; + + // Generate divs for the chart title, xlabel and ylabel. + // Space for these divs has already been taken away from the charting area in + // the DygraphCanvasRenderer constructor. + if (this.attr_('title')) { + div = document.createElement("div"); + div.style.position = 'absolute'; + div.style.top = '0px'; + div.style.left = this.area.x + 'px'; + div.style.width = this.area.w + 'px'; + div.style.height = this.attr_('titleHeight') + 'px'; + div.style.textAlign = 'center'; + div.style.fontSize = (this.attr_('titleHeight') - 8) + 'px'; + div.style.fontWeight = 'bold'; + class_div = document.createElement("div"); + class_div.className = 'dygraph-label dygraph-title'; + class_div.innerHTML = this.attr_('title'); + div.appendChild(class_div); + this.container.appendChild(div); + this.chartLabels.title = div; + } + + if (this.attr_('xlabel')) { + div = document.createElement("div"); + div.style.position = 'absolute'; + div.style.bottom = 0; // TODO(danvk): this is lazy. Calculate style.top. + div.style.left = this.area.x + 'px'; + div.style.width = this.area.w + 'px'; + div.style.height = this.attr_('xLabelHeight') + 'px'; + div.style.textAlign = 'center'; + div.style.fontSize = (this.attr_('xLabelHeight') - 2) + 'px'; + + class_div = document.createElement("div"); + class_div.className = 'dygraph-label dygraph-xlabel'; + class_div.innerHTML = this.attr_('xlabel'); + div.appendChild(class_div); + this.container.appendChild(div); + this.chartLabels.xlabel = div; + } + + var that = this; + function createRotatedDiv(axis, classes, html) { + var box = { + left: 0, + top: that.area.y, + width: that.attr_('yLabelWidth'), + height: that.area.h + }; + // TODO(danvk): is this outer div actually necessary? + div = document.createElement("div"); + div.style.position = 'absolute'; + if (axis == 1) { + div.style.left = box.left; + } else { + div.style.right = box.left; + } + div.style.top = box.top + 'px'; + div.style.width = box.width + 'px'; + div.style.height = box.height + 'px'; + div.style.fontSize = (that.attr_('yLabelWidth') - 2) + 'px'; + + var inner_div = document.createElement("div"); + inner_div.style.position = 'absolute'; + inner_div.style.width = box.height + 'px'; + inner_div.style.height = box.width + 'px'; + 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. + var val = 'rotate(' + (axis == 1 ? '-' : '') + '90deg)'; + inner_div.style.transform = val; // HTML5 + inner_div.style.WebkitTransform = val; // Safari/Chrome + inner_div.style.MozTransform = val; // Firefox + inner_div.style.OTransform = val; // Opera + inner_div.style.msTransform = val; // IE9 + + 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=' + + (axis == 1 ? '3' : '1') + ')'; + inner_div.style.left = '0px'; + inner_div.style.top = '0px'; + } + + class_div = document.createElement("div"); + class_div.className = classes; + class_div.innerHTML = html; + + inner_div.appendChild(class_div); + div.appendChild(inner_div); + return div; + } + + var div; + if (this.attr_('ylabel')) { + div = createRotatedDiv(1, 'dygraph-label dygraph-ylabel', + this.attr_('ylabel')); + this.container.appendChild(div); + this.chartLabels.ylabel = div; + } + if (this.attr_('y2label') && this.dygraph_.numAxes() == 2) { + div = createRotatedDiv(2, 'dygraph-label dygraph-y2label', + this.attr_('y2label')); + this.container.appendChild(div); + this.chartLabels.y2label = div; + } +}; + + +DygraphCanvasRenderer.prototype._renderAnnotations = function() { + var annotationStyle = { + "position": "absolute", + "fontSize": this.attr_('axisLabelFontSize') + "px", + "zIndex": 10, + "overflow": "hidden" + }; + + var bindEvt = function(eventName, classEventName, p, self) { + return function(e) { + var a = p.annotation; + if (a.hasOwnProperty(eventName)) { + a[eventName](a, p, self.dygraph_, e); + } else if (self.dygraph_.attr_(classEventName)) { + self.dygraph_.attr_(classEventName)(a, p, self.dygraph_,e ); + } + }; + }; + + // Get a list of point with annotations. + var points = this.layout.annotated_points; + for (var i = 0; i < points.length; i++) { + var p = points[i]; + if (p.canvasx < this.area.x || p.canvasx > this.area.x + this.area.w || + p.canvasy < this.area.y || p.canvasy > this.area.y + this.area.h) { + continue; + } + + var a = p.annotation; + var tick_height = 6; + if (a.hasOwnProperty("tickHeight")) { + tick_height = a.tickHeight; + } + + var div = document.createElement("div"); + for (var name in annotationStyle) { + if (annotationStyle.hasOwnProperty(name)) { + div.style[name] = annotationStyle[name]; + } + } + if (!a.hasOwnProperty('icon')) { + div.className = "dygraphDefaultAnnotation"; + } + if (a.hasOwnProperty('cssClass')) { + div.className += " " + a.cssClass; + } + + var width = a.hasOwnProperty('width') ? a.width : 16; + var height = a.hasOwnProperty('height') ? a.height : 16; + if (a.hasOwnProperty('icon')) { + var img = document.createElement("img"); + img.src = a.icon; + img.width = width; + img.height = height; + div.appendChild(img); + } else if (p.annotation.hasOwnProperty('shortText')) { + div.appendChild(document.createTextNode(p.annotation.shortText)); + } + div.style.left = (p.canvasx - width / 2) + "px"; + if (a.attachAtBottom) { + div.style.top = (this.area.h - height - tick_height) + "px"; + } else { + div.style.top = (p.canvasy - height - tick_height) + "px"; + } + div.style.width = width + "px"; + div.style.height = height + "px"; + div.title = p.annotation.text; + div.style.color = this.colors[p.name]; + div.style.borderColor = this.colors[p.name]; + a.div = div; + + this.dygraph_.addEvent(div, 'click', + bindEvt('clickHandler', 'annotationClickHandler', p, this)); + this.dygraph_.addEvent(div, 'mouseover', + bindEvt('mouseOverHandler', 'annotationMouseOverHandler', p, this)); + this.dygraph_.addEvent(div, 'mouseout', + bindEvt('mouseOutHandler', 'annotationMouseOutHandler', p, this)); + this.dygraph_.addEvent(div, 'dblclick', + bindEvt('dblClickHandler', 'annotationDblClickHandler', p, this)); + + this.container.appendChild(div); + this.annotations.push(div); + + var ctx = this.elementContext; + ctx.strokeStyle = this.colors[p.name]; + ctx.beginPath(); + if (!a.attachAtBottom) { + ctx.moveTo(p.canvasx, p.canvasy); + ctx.lineTo(p.canvasx, p.canvasy - 2 - tick_height); + } else { + ctx.moveTo(p.canvasx, this.area.h); + ctx.lineTo(p.canvasx, this.area.h - 2 - tick_height); + } + ctx.closePath(); + ctx.stroke(); + } +}; + +DygraphCanvasRenderer.makeNextPointStep_ = function(connect, points, end) { + if (connect) { + return function(j) { + while (++j < end) { + if (!(points[j].yval === null)) break; + } + return j; + } + } else { + return function(j) { return j + 1 }; + } +}; + +DygraphCanvasRenderer.prototype._drawStyledLine = function( + ctx, i, setName, color, strokeWidth, strokePattern, drawPoints, + drawPointCallback, pointSize) { + var isNullOrNaN = function(x) { + return (x === null || isNaN(x)); + }; + + var stepPlot = this.attr_("stepPlot"); + var firstIndexInSet = this.layout.setPointsOffsets[i]; + var setLength = this.layout.setPointsLengths[i]; + var afterLastIndexInSet = firstIndexInSet + setLength; + var points = this.layout.points; + var prevX = null; + var prevY = null; + var pointsOnLine = []; // Array of [canvasx, canvasy] pairs. + if (!Dygraph.isArrayLike(strokePattern)) { + strokePattern = null; + } + + var point; + var next = DygraphCanvasRenderer.makeNextPointStep_( + this.attr_('connectSeparatedPoints'), points, afterLastIndexInSet); + ctx.save(); + for (var j = firstIndexInSet; j < afterLastIndexInSet; j = next(j)) { + point = points[j]; + 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'); + this._dashedLine(ctx, prevX, prevY, point.canvasx, prevY, strokePattern); + 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 = strokeWidth; + if (stepPlot) { + this._dashedLine(ctx, prevX, prevY, point.canvasx, prevY, strokePattern); + prevX = point.canvasx; + } + this._dashedLine(ctx, prevX, prevY, point.canvasx, point.canvasy, strokePattern); + prevX = point.canvasx; + prevY = point.canvasy; + ctx.stroke(); + } + } + + if (drawPoints || isIsolated) { + pointsOnLine.push([point.canvasx, point.canvasy]); + } + } + } + for (var idx = 0; idx < pointsOnLine.length; idx++) { + var cb = pointsOnLine[idx]; + ctx.save(); + drawPointCallback( + this.dygraph_, setName, ctx, cb[0], cb[1], color, pointSize); + ctx.restore(); } + ctx.restore(); +}; + +DygraphCanvasRenderer.prototype._drawLine = function(ctx, i) { + var setNames = this.layout.setNames; + var setName = setNames[i]; + + var strokeWidth = this.dygraph_.attr_("strokeWidth", setName); + var borderWidth = this.dygraph_.attr_("strokeBorderWidth", setName); + var drawPointCallback = this.dygraph_.attr_("drawPointCallback", setName) || + Dygraph.Circles.DEFAULT; + if (borderWidth && strokeWidth) { + this._drawStyledLine(ctx, i, setName, + this.dygraph_.attr_("strokeBorderColor", setName), + strokeWidth + 2 * borderWidth, + this.dygraph_.attr_("strokePattern", setName), + this.dygraph_.attr_("drawPoints", setName), + drawPointCallback, + this.dygraph_.attr_("pointSize", setName)); + } + + this._drawStyledLine(ctx, i, setName, + this.colors[setName], + strokeWidth, + this.dygraph_.attr_("strokePattern", setName), + this.dygraph_.attr_("drawPoints", setName), + drawPointCallback, + this.dygraph_.attr_("pointSize", setName)); }; /** - * Overrides the CanvasRenderer method to draw error bars + * Actually draw the lines chart, including error bars. + * TODO(danvk): split this into several smaller functions. + * @private */ -DateGraphCanvasRenderer.prototype._renderLineChart = function() { - var context = this.element.getContext("2d"); - var colorCount = this.options.colorScheme.length; - var colorScheme = this.options.colorScheme; - var setNames = MochiKit.Base.keys(this.layout.datasets); - var errorBars = this.layout.options.errorBars; +DygraphCanvasRenderer.prototype._renderLineChart = function() { + // TODO(danvk): use this.attr_ for many of these. + var ctx = this.elementContext; + var fillAlpha = this.attr_('fillAlpha'); + var errorBars = this.attr_("errorBars") || this.attr_("customBars"); + var fillGraph = this.attr_("fillGraph"); + var stackedGraph = this.attr_("stackedGraph"); + var stepPlot = this.attr_("stepPlot"); + var points = this.layout.points; + var pointsLength = points.length; + var point, i, j, prevX, prevY, prevYs, color, setName, newYs, err_color, rgb, yscale, axis; + + var setNames = this.layout.setNames; var setCount = setNames.length; - var bind = MochiKit.Base.bind; - var partial = MochiKit.Base.partial; - //Update Points - var updatePoint = function(point) { + // TODO(danvk): Move this mapping into Dygraph and get it out of here. + this.colors = {}; + for (i = 0; i < setCount; i++) { + this.colors[setNames[i]] = this.colorScheme_[i % this.colorScheme_.length]; + } + + // Update Points + // TODO(danvk): here + for (i = pointsLength; i--;) { + point = points[i]; point.canvasx = this.area.w * point.x + this.area.x; point.canvasy = this.area.h * point.y + this.area.y; } - MochiKit.Iter.forEach(this.layout.points, updatePoint, this); // create paths - var makePath = function(ctx) { - for (var i = 0; i < setCount; i++) { - var setName = setNames[i]; - var color = colorScheme[i%colorCount]; - var strokeX = this.options.strokeColorTransform; + if (errorBars) { + ctx.save(); + if (fillGraph) { + this.dygraph_.warn("Can't use fillGraph option with error bars"); + } + + for (i = 0; i < setCount; i++) { + setName = setNames[i]; + axis = this.dygraph_.axisPropertiesForSeries(setName); + color = this.colors[setName]; + + var firstIndexInSet = this.layout.setPointsOffsets[i]; + var setLength = this.layout.setPointsLengths[i]; + var afterLastIndexInSet = firstIndexInSet + setLength; + + var next = DygraphCanvasRenderer.makeNextPointStep_( + this.attr_('connectSeparatedPoints'), points, + afterLastIndexInSet); // setup graphics context - context.save(); - context.strokeStyle = color.toRGBString(); - context.lineWidth = this.options.strokeWidth; + prevX = NaN; + prevY = NaN; + prevYs = [-1, -1]; + yscale = axis.yscale; + // should be same color as the lines but only 15% opaque. + rgb = new RGBColor(color); + err_color = 'rgba(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ',' + + fillAlpha + ')'; + ctx.fillStyle = err_color; ctx.beginPath(); - var point = this.layout.points[0]; - var first_point = true; - var addPoint = function(ctx_, point) { - if (point.name == setName) { - if (first_point) - ctx_.moveTo(point.canvasx, point.canvasy); - else - ctx_.lineTo(point.canvasx, point.canvasy); - first_point = false; + for (j = firstIndexInSet; j < afterLastIndexInSet; j = next(j)) { + point = points[j]; + if (point.name == setName) { // TODO(klausw): this is always true + if (!Dygraph.isOK(point.y)) { + prevX = NaN; + continue; + } + + // TODO(danvk): here + if (stepPlot) { + newYs = [ point.y_bottom, point.y_top ]; + prevY = point.y; + } else { + 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; + if (!isNaN(prevX)) { + if (stepPlot) { + ctx.moveTo(prevX, newYs[0]); + } else { + ctx.moveTo(prevX, prevYs[0]); + } + ctx.lineTo(point.canvasx, newYs[0]); + ctx.lineTo(point.canvasx, newYs[1]); + if (stepPlot) { + ctx.lineTo(prevX, newYs[1]); + } else { + ctx.lineTo(prevX, prevYs[1]); + } + ctx.closePath(); + } + prevYs = newYs; + prevX = point.canvasx; } - }; - MochiKit.Iter.forEach(this.layout.points, partial(addPoint, ctx), this); - ctx.stroke(); + } + ctx.fill(); } - }; + ctx.restore(); + } else if (fillGraph) { + ctx.save(); + var baseline = {}; // for stacked graphs: baseline for filling + var currBaseline; + + // process sets in reverse order (needed for stacked graphs) + for (i = setCount - 1; i >= 0; i--) { + setName = setNames[i]; + color = this.colors[setName]; + 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; + axisY = this.area.h * axisY + this.area.y; + var firstIndexInSet = this.layout.setPointsOffsets[i]; + var setLength = this.layout.setPointsLengths[i]; + var afterLastIndexInSet = firstIndexInSet + setLength; - var makeErrorBars = function(ctx) { - for (var i = 0; i < setCount; i++) { - var setName = setNames[i]; - var color = colorScheme[i % colorCount]; - var strokeX = this.options.strokeColorTransform; + var next = DygraphCanvasRenderer.makeNextPointStep_( + this.attr_('connectSeparatedPoints'), points, + afterLastIndexInSet); // setup graphics context - context.save(); - context.strokeStyle = color.toRGBString(); - context.lineWidth = this.options.strokeWidth; - var prevX = -1; - var prevYs = [-1, -1]; - var count = 0; - var yscale = this.layout.yscale; - var errorTrapezoid = function(ctx_,point) { - count++; - if (point.name == setName) { - var newYs = [ point.y - point.errorPlus * yscale, - point.y + point.errorMinus * yscale ]; - newYs[0] = this.area.h * newYs[0] + this.area.y; - newYs[1] = this.area.h * newYs[1] + this.area.y; - if (prevX >= 0) { - ctx_.moveTo(prevX, prevYs[0]); - ctx_.lineTo(point.canvasx, newYs[0]); - ctx_.lineTo(point.canvasx, newYs[1]); - ctx_.lineTo(prevX, prevYs[1]); - ctx_.closePath(); + prevX = NaN; + prevYs = [-1, -1]; + yscale = axis.yscale; + // should be same color as the lines but only 15% opaque. + rgb = new RGBColor(color); + err_color = 'rgba(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ',' + + fillAlpha + ')'; + ctx.fillStyle = err_color; + ctx.beginPath(); + for (j = firstIndexInSet; j < afterLastIndexInSet; j = next(j)) { + point = points[j]; + if (point.name == setName) { // TODO(klausw): this is always true + if (!Dygraph.isOK(point.y)) { + prevX = NaN; + continue; + } + if (stackedGraph) { + currBaseline = baseline[point.canvasx]; + var lastY; + if (currBaseline === undefined) { + lastY = axisY; + } else { + if(stepPlot) { + lastY = currBaseline[0]; + } else { + lastY = currBaseline; + } + } + newYs = [ point.canvasy, lastY ]; + + if(stepPlot) { + // Step plots must keep track of the top and bottom of + // the baseline at each point. + if(prevYs[0] === -1) { + baseline[point.canvasx] = [ point.canvasy, axisY ]; + } else { + baseline[point.canvasx] = [ point.canvasy, prevYs[0] ]; + } + } else { + baseline[point.canvasx] = point.canvasy; + } + + } else { + newYs = [ point.canvasy, axisY ]; + } + if (!isNaN(prevX)) { + ctx.moveTo(prevX, prevYs[0]); + + if (stepPlot) { + ctx.lineTo(point.canvasx, prevYs[0]); + if(currBaseline) { + // Draw to the bottom of the baseline + ctx.lineTo(point.canvasx, currBaseline[1]); + } else { + ctx.lineTo(point.canvasx, newYs[1]); + } + } else { + ctx.lineTo(point.canvasx, newYs[0]); + ctx.lineTo(point.canvasx, newYs[1]); + } + + ctx.lineTo(prevX, prevYs[1]); + ctx.closePath(); } - prevYs[0] = newYs[0]; - prevYs[1] = newYs[1]; + prevYs = newYs; prevX = point.canvasx; } - }; - // should be same color as the lines - var err_color = color.colorWithAlpha(0.15); - ctx.fillStyle = err_color.toRGBString(); - ctx.beginPath(); - MochiKit.Iter.forEach(this.layout.points, partial(errorTrapezoid, ctx), this); + } ctx.fill(); } - }; + ctx.restore(); + } - if (errorBars) - bind(makeErrorBars, this)(context); - bind(makePath, this)(context); - context.restore(); + // Drawing the lines. + for (i = 0; i < setCount; i += 1) { + this._drawLine(ctx, i); + } +}; + +/** + * This does dashed lines onto a canvas for a given pattern. You must call + * ctx.stroke() after to actually draw it, much line ctx.lineTo(). It remembers + * the state of the line in regards to where we left off on drawing the pattern. + * You can draw a dashed line in several function calls and the pattern will be + * continous as long as you didn't call this function with a different pattern + * in between. + * @param ctx The canvas 2d context to draw on. + * @param x The start of the line's x coordinate. + * @param y The start of the line's y coordinate. + * @param x2 The end of the line's x coordinate. + * @param y2 The end of the line's y coordinate. + * @param pattern The dash pattern to draw, an array of integers where even + * index is drawn and odd index is not drawn (Ex. [10, 2, 5, 2], 10 is drawn 5 + * is drawn, 2 is the space between.). A null pattern, array of length one, or + * empty array will do just a solid line. + * @private + */ +DygraphCanvasRenderer.prototype._dashedLine = function(ctx, x, y, x2, y2, pattern) { + // Original version http://stackoverflow.com/questions/4576724/dotted-stroke-in-canvas + // Modified by Russell Valentine to keep line history and continue the pattern + // where it left off. + var dx, dy, len, rot, patternIndex, segment; + + // If we don't have a pattern or it is an empty array or of size one just + // do a solid line. + if (!pattern || pattern.length <= 1) { + ctx.moveTo(x, y); + ctx.lineTo(x2, y2); + return; + } + + // If we have a different dash pattern than the last time this was called we + // reset our dash history and start the pattern from the begging + // regardless of state of the last pattern. + if (!Dygraph.compareArrays(pattern, this._dashedLineToHistoryPattern)) { + this._dashedLineToHistoryPattern = pattern; + this._dashedLineToHistory = [0, 0]; + } + ctx.save(); + + // Calculate transformation parameters + dx = (x2-x); + dy = (y2-y); + len = Math.sqrt(dx*dx + dy*dy); + rot = Math.atan2(dy, dx); + + // Set transformation + ctx.translate(x, y); + ctx.moveTo(0, 0); + ctx.rotate(rot); + + // Set last pattern index we used for this pattern. + patternIndex = this._dashedLineToHistory[0]; + x = 0; + while (len > x) { + // Get the length of the pattern segment we are dealing with. + segment = pattern[patternIndex]; + // If our last draw didn't complete the pattern segment all the way we + // will try to finish it. Otherwise we will try to do the whole segment. + if (this._dashedLineToHistory[1]) { + x += this._dashedLineToHistory[1]; + } else { + x += segment; + } + if (x > len) { + // We were unable to complete this pattern index all the way, keep + // where we are the history so our next draw continues where we left off + // in the pattern. + this._dashedLineToHistory = [patternIndex, x-len]; + x = len; + } else { + // We completed this patternIndex, we put in the history that we are on + // the beginning of the next segment. + this._dashedLineToHistory = [(patternIndex+1)%pattern.length, 0]; + } + + // We do a line on a even pattern index and just move on a odd pattern index. + // The move is the empty space in the dash. + if(patternIndex % 2 === 0) { + ctx.lineTo(x, 0); + } else { + ctx.moveTo(x, 0); + } + // If we are not done, next loop process the next pattern segment, or the + // first segment again if we are at the end of the pattern. + patternIndex = (patternIndex+1) % pattern.length; + } + ctx.restore(); };