X-Git-Url: https://adrianiainlam.tk/git/?a=blobdiff_plain;f=dygraph-canvas.js;h=2874990041c65bf93d36ccc9343dd4c002768402;hb=2cf95fff7f77658eccb3d00e7d52d081863c61ff;hp=bf04e13d406097daf51446cc72a26fe974a3853a;hpb=895b3657b0ab22bb35815a1687c71116b2d8b36c;p=dygraphs.git diff --git a/dygraph-canvas.js b/dygraph-canvas.js index bf04e13..2874990 100644 --- a/dygraph-canvas.js +++ b/dygraph-canvas.js @@ -4,9 +4,27 @@ /** * @fileoverview Based on PlotKit, but modified to meet the needs of dygraphs. * In particular, support for: - * - grid overlays + * - 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. */ /** @@ -19,7 +37,7 @@ DygraphLayout = function(dygraph, options) { this.options = {}; // TODO(danvk): remove, use attr_ instead. Dygraph.update(this.options, options ? options : {}); this.datasets = new Array(); - this.annotations = new Array() + this.annotations = new Array(); }; DygraphLayout.prototype.attr_ = function(name) { @@ -32,8 +50,9 @@ DygraphLayout.prototype.addDataset = function(setname, set_xy) { DygraphLayout.prototype.setAnnotations = function(ann) { // The Dygraph object's annotations aren't parsed. We parse them here and - // save a copy. - var parse = this.attr_('xValueParser'); + // 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) { @@ -69,20 +88,35 @@ DygraphLayout.prototype._evaluateLimits = function() { for (var name in this.datasets) { if (!this.datasets.hasOwnProperty(name)) continue; var series = this.datasets[name]; - 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; + 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); - this.minyval = this.options.yAxis[0]; - this.maxyval = this.options.yAxis[1]; - this.yrange = this.maxyval - this.minyval; - this.yscale = (this.yrange != 0 ? 1/this.yrange : 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() { @@ -92,24 +126,26 @@ DygraphLayout.prototype._evaluateLineCharts = function() { 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: 1.0 - ((parseFloat(item[1]) - this.minyval) * this.yscale), + y: yval, xval: parseFloat(item[0]), yval: parseFloat(item[1]), name: setName }; - // limit the x, y values so they do not overdraw - if (point.y <= 0.0) { - point.y = 0.0; - } - if (point.y >= 1.0) { - point.y = 1.0; - } this.points.push(point); } } @@ -127,12 +163,15 @@ DygraphLayout.prototype._evaluateLineTicks = function() { } this.yticks = new Array(); - for (var i = 0; i < this.options.yTicks.length; i++) { - var tick = this.options.yTicks[i]; - var label = tick.label; - var pos = 1.0 - (this.yscale * (tick.v - this.minyval)); - if ((pos >= 0.0) && (pos <= 1.0)) { - this.yticks.push([pos, label]); + 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]); + } } } }; @@ -238,10 +277,13 @@ DygraphLayout.prototype.unstackPointAtIndex = function(idx) { /** * Sets some PlotKit.CanvasRenderer options * @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 */ -DygraphCanvasRenderer = function(dygraph, element, layout, options) { +DygraphCanvasRenderer = function(dygraph, element, elementContext, layout, + options) { // TODO(danvk): remove options, just use dygraph.attr_. this.dygraph_ = dygraph; @@ -267,6 +309,7 @@ DygraphCanvasRenderer = function(dygraph, element, layout, options) { this.layout = layout; this.element = element; + this.elementContext = elementContext; this.container = this.element.parentNode; this.height = this.element.height; @@ -280,8 +323,11 @@ DygraphCanvasRenderer = function(dygraph, element, layout, options) { this.xlabels = new Array(); this.ylabels = new Array(); this.annotations = new Array(); + this.chartLabels = {}; + // TODO(danvk): consider all axes in this computation. this.area = { + // TODO(danvk): per-axis setting. x: this.options.yAxisLabelWidth + 2 * this.options.axisTickSize, y: 0 }; @@ -289,8 +335,48 @@ DygraphCanvasRenderer = function(dygraph, element, layout, options) { this.area.h = this.height - this.options.axisLabelFontSize - 2 * this.options.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); + } else if (this.dygraph_.numAxes() > 2) { + this.dygraph_.error("Only two y-axes are supported at this time. (Trying " + + "to use " + this.dygraph_.numAxes() + ")"); + } + + // 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'); + } + if (this.attr_('xlabel')) { + this.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 + // label, but the default yAxisLabelWidth is large enough that this results + // in overly-padded charts. The y-axis label should fit fine. If it + // 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_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); }; DygraphCanvasRenderer.prototype.clear = function() { @@ -301,7 +387,7 @@ 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. @@ -311,24 +397,30 @@ 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++) { var el = this.xlabels[i]; - el.parentNode.removeChild(el); + if (el.parentNode) el.parentNode.removeChild(el); } for (var i = 0; i < this.ylabels.length; i++) { var el = this.ylabels[i]; - el.parentNode.removeChild(el); + if (el.parentNode) el.parentNode.removeChild(el); } for (var i = 0; i < this.annotations.length; i++) { var el = this.annotations[i]; - el.parentNode.removeChild(el); + if (el.parentNode) el.parentNode.removeChild(el); + } + 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 = new Array(); this.ylabels = new Array(); this.annotations = new Array(); + this.chartLabels = {}; }; @@ -355,11 +447,16 @@ DygraphCanvasRenderer.isSupported = function(canvasName) { * Draw an X/Y grid on top of the existing plot */ DygraphCanvasRenderer.prototype.render = function() { - // Draw the new X/Y grid - var ctx = this.element.getContext("2d"); + // 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.options.underlayCallback) { - this.options.underlayCallback(ctx, this.area, this.layout, this.dygraph_); + // 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_); } if (this.options.drawYGrid) { @@ -368,8 +465,10 @@ DygraphCanvasRenderer.prototype.render = function() { ctx.strokeStyle = this.options.gridLineColor; 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; + // TODO(danvk): allow secondary axes to draw a grid, too. + if (ticks[i][0] != 0) continue; + var x = halfUp(this.area.x); + var y = halfDown(this.area.y + ticks[i][1] * this.area.h); ctx.beginPath(); ctx.moveTo(x, y); ctx.lineTo(x + this.area.w, y); @@ -384,8 +483,8 @@ DygraphCanvasRenderer.prototype.render = function() { ctx.strokeStyle = this.options.gridLineColor; ctx.lineWidth = this.options.axisLineWidth; for (var i=0; i this.width) { @@ -515,8 +640,8 @@ DygraphCanvasRenderer.prototype._renderAxis = function() { } context.beginPath(); - context.moveTo(this.area.x, this.area.y + this.area.h); - context.lineTo(this.area.x + this.area.w, this.area.y + this.area.h); + 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(); } @@ -525,6 +650,101 @@ DygraphCanvasRenderer.prototype._renderAxis = function() { }; +DygraphCanvasRenderer.prototype._renderChartLabels = function() { + // 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')) { + var 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'; + var 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')) { + var 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'; + + var 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; + } + + if (this.attr_('ylabel')) { + var box = { + left: 0, + top: this.area.y, + width: this.attr_('yLabelWidth'), + height: this.area.h + }; + // TODO(danvk): is this outer div actually necessary? + var div = document.createElement("div"); + div.style.position = 'absolute'; + div.style.left = box.left; + div.style.top = box.top + 'px'; + div.style.width = box.width + 'px'; + div.style.height = box.height + 'px'; + div.style.fontSize = (this.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. + 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 + + 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'; + class_div.innerHTML = this.attr_('ylabel'); + + inner_div.appendChild(class_div); + div.appendChild(inner_div); + this.container.appendChild(div); + this.chartLabels.ylabel = div; + } +}; + + DygraphCanvasRenderer.prototype._renderAnnotations = function() { var annotationStyle = { "position": "absolute", @@ -607,7 +827,7 @@ 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) { @@ -627,12 +847,13 @@ DygraphCanvasRenderer.prototype._renderAnnotations = function() { * Overrides the CanvasRenderer method to draw error bars */ DygraphCanvasRenderer.prototype._renderLineChart = function() { - var context = this.element.getContext("2d"); + // TODO(danvk): use this.attr_ for many of these. + var context = this.elementContext; var colorCount = this.options.colorScheme.length; var colorScheme = this.options.colorScheme; var fillAlpha = this.options.fillAlpha; var errorBars = this.layout.options.errorBars; - var fillGraph = this.layout.options.fillGraph; + var fillGraph = this.attr_("fillGraph"); var stackedGraph = this.layout.options.stackedGraph; var stepPlot = this.layout.options.stepPlot; @@ -658,8 +879,6 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() { } // create paths - var isOK = function(x) { return x && !isNaN(x); }; - var ctx = context; if (errorBars) { if (fillGraph) { @@ -668,6 +887,8 @@ 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 color = this.colors[setName]; // setup graphics context @@ -675,7 +896,7 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() { var prevX = NaN; var prevY = NaN; var prevYs = [-1, -1]; - var yscale = this.layout.yscale; + var yscale = axis.yscale; // should be same color as the lines but only 15% opaque. var rgb = new RGBColor(color); var err_color = 'rgba(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ',' + @@ -685,7 +906,7 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() { for (var j = 0; j < this.layout.points.length; j++) { var point = this.layout.points[j]; if (point.name == setName) { - if (!isOK(point.y)) { + if (!Dygraph.isOK(point.y)) { prevX = NaN; continue; } @@ -723,23 +944,24 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() { ctx.fill(); } } else if (fillGraph) { - var axisY = 1.0 + this.layout.minyval * this.layout.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 baseline = [] // for stacked graphs: baseline for filling // process sets in reverse order (needed for stacked graphs) 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 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; // setup graphics context ctx.save(); var prevX = NaN; var prevYs = [-1, -1]; - var yscale = this.layout.yscale; + var yscale = axis.yscale; // should be same color as the lines but only 15% opaque. var rgb = new RGBColor(color); var err_color = 'rgba(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ',' + @@ -749,7 +971,7 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() { for (var j = 0; j < this.layout.points.length; j++) { var point = this.layout.points[j]; if (point.name == setName) { - if (!isOK(point.y)) { + if (!Dygraph.isOK(point.y)) { prevX = NaN; continue; } @@ -796,14 +1018,23 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() { for (var j = 0; j < points.length; j++) { var point = points[j]; if (point.name == setName) { - if (!isOK(point.canvasy)) { + if (!Dygraph.isOK(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.options.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 || - !isOK(points[j+1].canvasy))); + !Dygraph.isOK(points[j+1].canvasy))); if (!prevX) { prevX = point.canvasx;