X-Git-Url: https://adrianiainlam.tk/git/?a=blobdiff_plain;f=dygraph-canvas.js;h=4606dfb906a00c89c9c20ca392902eac61e569ba;hb=0f20de1c01823dd14dadff582c264a05605ee67b;hp=2eb5ce1bb296bb702ee20ecda268cff330416837;hpb=476007577849faaa48d1c6d8405ca1c5b75dcdd4;p=dygraphs.git diff --git a/dygraph-canvas.js b/dygraph-canvas.js index 2eb5ce1..887c6ff 100644 --- a/dygraph-canvas.js +++ b/dygraph-canvas.js @@ -1,198 +1,57 @@ -// 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 + * - grid overlays * - error bars * - dygraphs attribute system */ /** - * 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(); -}; - -DygraphLayout.prototype.attr_ = function(name) { - return this.dygraph_.attr_(name); -}; - -DygraphLayout.prototype.addDataset = function(setname, set_xy) { - this.datasets[setname] = set_xy; -}; - -DygraphLayout.prototype.evaluate = function() { - this._evaluateLimits(); - this._evaluateLineCharts(); - this._evaluateLineTicks(); -}; - -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]; - 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); -}; - -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]; - for (var j = 0; j < dataset.length; j++) { - var item = dataset[j]; - var point = { - // TODO(danvk): here - x: ((parseFloat(item[0]) - this.minxval) * this.xscale), - y: 1.0 - ((parseFloat(item[1]) - this.minyval) * this.yscale), - 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); - } - } -}; - -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.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]); - } - } -}; - - -/** - * 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]); - } - } - } -}; - -/** - * Convenience function to remove all the data sets from a graph + * 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 */ -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 : {}); -}; +/*jshint globalstrict: true */ +/*global Dygraph:false,RGBColor:false */ +"use strict"; -// Subclass PlotKit.CanvasRenderer to add: -// 1. X/Y grid overlay -// 2. Ability to draw error bars (if required) /** - * Sets some PlotKit.CanvasRenderer options - * @param {Object} element The canvas to attach to - * @param {Layout} layout The DygraphLayout object for this graph. - * @param {Object} options Options to pass on to CanvasRenderer + * @constructor + * + * This gets called when there are "new points" to chart. This is generally the + * case when the underlying data being charted has changed. It is _not_ called + * in the common case that the user has zoomed or is panning the view. + * + * The chart canvas has already been created by the Dygraph object. The + * renderer simply gets a drawing context. + * + * @param {Dyraph} dygraph The chart to which this renderer belongs. + * @param {Canvas} element The <canvas> DOM element on which to draw. + * @param {CanvasRenderingContext2D} elementContext The drawing context. + * @param {DygraphLayout} layout The chart's DygraphLayout object. + * + * TODO(danvk): remove the elementContext property. */ -DygraphCanvasRenderer = function(dygraph, element, layout, options) { - // TODO(danvk): remove options, just use dygraph.attr_. +var 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; @@ -203,22 +62,43 @@ DygraphCanvasRenderer = function(dygraph, element, layout, options) { throw "Canvas is not supported."; // internal state - this.xlabels = new Array(); - this.ylabels = new Array(); - - this.area = { - x: this.options.yAxisLabelWidth + 2 * this.options.axisTickSize, - 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; - + 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(); + } + } +}; + +DygraphCanvasRenderer.prototype.attr_ = function(x) { + return this.dygraph_.attr_(x); }; +/** + * Clears out all chart content and DOM elements. + * This is called immediately before render() on every frame, including + * during zooms and pans. + * @private + */ DygraphCanvasRenderer.prototype.clear = function() { + var context; if (this.isIE) { // VML takes a while to start up, so we just poll every this.IEDelay try { @@ -226,40 +106,33 @@ DygraphCanvasRenderer.prototype.clear = function() { this.clearDelay.cancel(); this.clearDelay = null; } - var context = this.element.getContext("2d"); + 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)); + // this.clearDelay = MochiKit.Async.wait(this.IEDelay); + // this.clearDelay.addCallback(bind(this.clear, this)); return; } } - var context = this.element.getContext("2d"); + 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); - } - for (var i = 0; i < this.ylabels.length; i++) { - var el = this.ylabels[i]; - el.parentNode.removeChild(el); - } - this.xlabels = new Array(); - this.ylabels = new Array(); }; - +/** + * Checks whether the browser supports the <canvas> tag. + * @private + */ DygraphCanvasRenderer.isSupported = function(canvasName) { var canvas = null; try { - if (typeof(canvasName) == 'undefined' || canvasName == null) + if (typeof(canvasName) == 'undefined' || canvasName === null) { canvas = document.createElement("canvas"); - else + } else { canvas = canvasName; - var context = canvas.getContext("2d"); + } + canvas.getContext("2d"); } catch (e) { var ie = navigator.appVersion.match(/MSIE (\d\.\d)/); @@ -272,386 +145,492 @@ DygraphCanvasRenderer.isSupported = function(canvasName) { }; /** - * Draw an X/Y grid on top of the existing plot + * This method is responsible for drawing everything on the chart, including + * lines, error bars, fills and axes. + * It is called immediately after clear() on every frame, including during pans + * and zooms. + * @private */ DygraphCanvasRenderer.prototype.render = function() { - // Draw the new X/Y grid - var ctx = this.element.getContext("2d"); + this._renderLineChart(); +}; - if (this.options.underlayCallback) { - this.options.underlayCallback(ctx, this.area, this.layout, this.dygraph_); +DygraphCanvasRenderer.prototype._createIEClipArea = function() { + var className = 'dygraph-clip-div'; + var graphDiv = this.dygraph_.graphDiv; + + // Remove old clip divs. + for (var i = graphDiv.childNodes.length-1; i >= 0; i--) { + if (graphDiv.childNodes[i].className == className) { + graphDiv.removeChild(graphDiv.childNodes[i]); + } } - if (this.options.drawYGrid) { - var ticks = this.layout.yticks; - ctx.save(); - 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; - ctx.beginPath(); - ctx.moveTo(x, y); - ctx.lineTo(x + this.area.w, y); - ctx.closePath(); - ctx.stroke(); + // 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; } - if (this.options.drawXGrid) { - var ticks = this.layout.xticks; - ctx.save(); - ctx.strokeStyle = this.options.gridLineColor; - ctx.lineWidth = this.options.axisLineWidth; - for (var i=0; i 0) { - 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 y = this.area.y + tick[0] * this.area.h; - context.beginPath(); - context.moveTo(x, y); - context.lineTo(x - this.options.axisTickSize, y); - context.closePath(); - context.stroke(); - - var label = makeDiv(tick[1]); - var top = (y - this.options.axisLabelFontSize / 2); - if (top < 0) top = 0; - - if (top + this.options.axisLabelFontSize + 3 > this.height) { - label.style.bottom = "0px"; - } else { - label.style.top = top + "px"; - } - label.style.left = "0px"; - label.style.textAlign = "right"; - label.style.width = this.options.yAxisLabelWidth + "px"; - this.container.appendChild(label); - this.ylabels.push(label); - } +/** + * Returns a predicate to be used with an iterator, which will + * iterate over points appropriately, depending on whether + * connectSeparatedPoints is true. When it's false, the predicate will + * skip over points with missing yVals. + */ +DygraphCanvasRenderer._getIteratorPredicate = function(connectSeparatedPoints) { + return connectSeparatedPoints + ? DygraphCanvasRenderer._predicateThatSkipsEmptyPoints + : null; +}; - // 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.options.axisLabelFontSize; - var bottom = parseInt(bottomTick.style.top) + fontSize; - if (bottom > this.height - fontSize) { - bottomTick.style.top = (parseInt(bottomTick.style.top) - - fontSize / 2) + "px"; - } - } +DygraphCanvasRenderer._predicateThatSkipsEmptyPoints = + function(array, idx) { + return array[idx].yval !== null; +}; - context.beginPath(); - context.moveTo(this.area.x, this.area.y); - context.lineTo(this.area.x, this.area.y + this.area.h); - context.closePath(); - context.stroke(); +/** + * + * @private + */ +DygraphCanvasRenderer.prototype._drawStyledLine = function( + ctx, i, setName, color, strokeWidth, strokePattern, drawPoints, + drawPointCallback, pointSize) { + // TODO(konigsberg): Compute attributes outside this method call. + var stepPlot = this.attr_("stepPlot"); + var firstIndexInSet = this.layout.setPointsOffsets[i]; + var setLength = this.layout.setPointsLengths[i]; + var points = this.layout.points; + if (!Dygraph.isArrayLike(strokePattern)) { + strokePattern = null; } + var drawGapPoints = this.dygraph_.attr_('drawGapEdgePoints', setName); - if (this.options.drawXAxis) { - if (this.layout.xticks) { - for (var i = 0; i < this.layout.xticks.length; i++) { - var tick = this.layout.xticks[i]; - if (typeof(dataset) == "function") return; - - var x = this.area.x + tick[0] * this.area.w; - var y = this.area.y + this.area.h; - context.beginPath(); - context.moveTo(x, y); - context.lineTo(x, y + this.options.axisTickSize); - context.closePath(); - context.stroke(); - - var label = makeDiv(tick[1]); - label.style.textAlign = "center"; - label.style.bottom = "0px"; - - var left = (x - this.options.axisLabelWidth/2); - if (left + this.options.axisLabelWidth > this.width) { - left = this.width - this.options.xAxisLabelWidth; - label.style.textAlign = "right"; - } - if (left < 0) { - left = 0; - label.style.textAlign = "left"; + var iter = Dygraph.createIterator(points, firstIndexInSet, setLength, + DygraphCanvasRenderer._getIteratorPredicate( + this.attr_("connectSeparatedPoints"))); + + var stroking = strokePattern && (strokePattern.length >= 2); + + ctx.save(); + if (stroking) { + ctx.installPattern(strokePattern); + } + + var pointsOnLine = this._drawSeries(ctx, iter, strokeWidth, pointSize, drawPoints, drawGapPoints, stepPlot, color); + this._drawPointsOnLine(ctx, pointsOnLine, drawPointCallback, setName, color, pointSize); + + if (stroking) { + ctx.uninstallPattern(); + } + + ctx.restore(); +}; + +DygraphCanvasRenderer.prototype._drawPointsOnLine = function(ctx, pointsOnLine, drawPointCallback, setName, color, pointSize) { + 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(); + } +} + +DygraphCanvasRenderer.prototype._drawSeries = function( + ctx, iter, strokeWidth, pointSize, drawPoints, drawGapPoints, + stepPlot, color) { + + var prevCanvasX = null; + var prevCanvasY = null; + var nextCanvasY = null; + var isIsolated; // true if this point is isolated (no line segments) + var point; // the point being processed in the while loop + var pointsOnLine = []; // Array of [canvasx, canvasy] pairs. + var first = true; // the first cycle through the while loop + + ctx.beginPath(); + ctx.strokeStyle = color; + ctx.lineWidth = strokeWidth; + + for (var i = iter.start_; i < iter.end_; i++) { + // while (iter.hasNext) { + point = iter.array_[i]; + if (iter.predicate_) { + while (i < iter.end_ && !iter.predicate_(iter.array_, i)) { + i++; + } + if (i == iter.end_) break; + } + + if (point.canvasy === null || point.canvasy != point.canvasy) { + if (stepPlot && prevCanvasX !== null) { + // Draw a horizontal line to the start of the missing data + ctx.moveTo(prevX, prevY); + ctx.lineTo(point.canvasx, prevY); + } + prevCanvasX = prevCanvasY = null; + } else { + isIsolated = false; + if (drawGapPoints || !prevCanvasX) { + // nextCanvasY = iter.hasNext ? iter.peek.canvasy : null; + // var next_i = i + 1; + // while (next_i < iter.end_ && (!iter.predicate_ || !iter.predicate_(iter.array_, next_i))) { + // next_i++; + // } + iter.nextIdx_ = i; + var peek = iter.next(); + nextCanvasY = peek ? peek.canvasy : null; + // nextCanvasY = next_i < iter.end_ ? iter.array_[next_i].canvasy : null; + + // TODO: we calculate isNullOrNaN for this point, and the next, and then, + // when we iterate, test for isNullOrNaN again. Why bother? + var isNextCanvasYNullOrNaN = nextCanvasY === null || + nextCanvasY != nextCanvasY; + isIsolated = (!prevCanvasX && isNextCanvasYNullOrNaN); + if (drawGapPoints) { + // Also consider a point to be "isolated" if it's adjacent to a + // null point, excluding the graph edges. + if ((!first && !prevCanvasX) || + (iter.hasNext && isNextCanvasYNullOrNaN)) { + isIsolated = true; + } } + } - label.style.left = left + "px"; - label.style.width = this.options.xAxisLabelWidth + "px"; - this.container.appendChild(label); - this.xlabels.push(label); + if (prevCanvasX !== null) { + if (strokeWidth) { + if (stepPlot) { + ctx.moveTo(prevCanvasX, prevCanvasY); + ctx.lineTo(point.canvasx, prevCanvasY); + prevCanvasX = point.canvasx; + } + ctx.moveTo(prevCanvasX, prevCanvasY); + ctx.lineTo(point.canvasx, point.canvasy); + } } + if (drawPoints || isIsolated) { + pointsOnLine.push([point.canvasx, point.canvasy]); + } + prevCanvasX = point.canvasx; + prevCanvasY = point.canvasy; } + first = false; + } + ctx.stroke(); + return pointsOnLine; +}; - 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.closePath(); - context.stroke(); +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)); } - context.restore(); + 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. + * @private */ DygraphCanvasRenderer.prototype._renderLineChart = function() { - 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 fillGraph = this.layout.options.fillGraph; - var stackedGraph = this.layout.options.stackedGraph; - var stepPlot = this.layout.options.stepPlot; - - var setNames = []; - for (var name in this.layout.datasets) { - if (this.layout.datasets.hasOwnProperty(name)) { - setNames.push(name); - } - } + var ctx = this.elementContext; + var errorBars = this.attr_("errorBars") || this.attr_("customBars"); + var fillGraph = this.attr_("fillGraph"); + var i; + + var setNames = this.layout.setNames; var setCount = setNames.length; - this.colors = {} - for (var i = 0; i < setCount; i++) { - this.colors[setNames[i]] = colorScheme[i % colorCount]; - } + this.colors = this.dygraph_.colorsMap_; // Update Points // TODO(danvk): here - for (var i = 0; i < this.layout.points.length; i++) { - var point = this.layout.points[i]; + // + // TODO(bhs): this loop is a hot-spot for high-point-count charts. These + // transformations can be pushed into the canvas via linear transformation + // matrices. + var points = this.layout.points; + for (i = points.length; 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; } - // create paths - var isOK = function(x) { return x && !isNaN(x); }; - - var ctx = context; + // Draw any "fills", i.e. error bars or the filled area under a series. + // These must all be drawn before any lines, so that the main lines of a + // series are drawn on top. if (errorBars) { if (fillGraph) { this.dygraph_.warn("Can't use fillGraph option with error bars"); } - for (var i = 0; i < setCount; i++) { - var setName = setNames[i]; - var color = this.colors[setName]; - - // setup graphics context - ctx.save(); - var prevX = NaN; - var prevY = NaN; - var prevYs = [-1, -1]; - var yscale = this.layout.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 + ',' + - fillAlpha + ')'; - ctx.fillStyle = err_color; - ctx.beginPath(); - for (var j = 0; j < this.layout.points.length; j++) { - var point = this.layout.points[j]; - if (point.name == setName) { - if (!isOK(point.y)) { - prevX = NaN; - continue; - } - // TODO(danvk): here - if (stepPlot) { - var newYs = [ prevY - point.errorPlus * yscale, - prevY + point.errorMinus * yscale ]; - prevY = point.y; - } else { - 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 (!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; - } - } - ctx.fill(); - } + ctx.save(); + this.drawErrorBars_(points); + ctx.restore(); } 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; + ctx.save(); + this.drawFillBars_(points); + ctx.restore(); + } - 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]; - - // setup graphics context - ctx.save(); - var prevX = NaN; - var prevYs = [-1, -1]; - var yscale = this.layout.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 + ',' + - fillAlpha + ')'; - ctx.fillStyle = err_color; - ctx.beginPath(); - for (var j = 0; j < this.layout.points.length; j++) { - var point = this.layout.points[j]; - if (point.name == setName) { - if (!isOK(point.y)) { - prevX = NaN; - continue; - } - var newYs; - if (stackedGraph) { - lastY = baseline[point.canvasx]; - if (lastY === undefined) lastY = axisY; - baseline[point.canvasx] = point.canvasy; - newYs = [ point.canvasy, lastY ]; - } else { - newYs = [ point.canvasy, axisY ]; - } - if (!isNaN(prevX)) { - ctx.moveTo(prevX, prevYs[0]); - if (stepPlot) { - ctx.lineTo(point.canvasx, prevYs[0]); - } else { - ctx.lineTo(point.canvasx, newYs[0]); - } - ctx.lineTo(point.canvasx, newYs[1]); - ctx.lineTo(prevX, prevYs[1]); - ctx.closePath(); - } - prevYs = newYs; - prevX = point.canvasx; + // Drawing the lines. + for (i = 0; i < setCount; i += 1) { + this._drawLine(ctx, i); + } +}; + +/** + * Draws the shaded error bars/confidence intervals for each series. + * This happens before the center lines are drawn, since the center lines + * need to be drawn on top of the error bars for all series. + * + * @private + */ +DygraphCanvasRenderer.prototype.drawErrorBars_ = function(points) { + var ctx = this.elementContext; + var setNames = this.layout.setNames; + var setCount = setNames.length; + var fillAlpha = this.attr_('fillAlpha'); + var stepPlot = this.attr_('stepPlot'); + + var newYs; + + for (var i = 0; i < setCount; i++) { + var setName = setNames[i]; + var axis = this.dygraph_.axisPropertiesForSeries(setName); + var color = this.colors[setName]; + + var firstIndexInSet = this.layout.setPointsOffsets[i]; + var setLength = this.layout.setPointsLengths[i]; + + var iter = Dygraph.createIterator(points, firstIndexInSet, setLength, + DygraphCanvasRenderer._getIteratorPredicate( + this.attr_("connectSeparatedPoints"))); + + // setup graphics context + var prevX = NaN; + var prevY = NaN; + var prevYs = [-1, -1]; + 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 + ',' + fillAlpha + ')'; + ctx.fillStyle = err_color; + ctx.beginPath(); + while (iter.hasNext) { + var point = iter.next(); + 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(); } - ctx.fill(); + prevYs = newYs; + prevX = point.canvasx; } + ctx.fill(); } +}; - for (var i = 0; i < setCount; i++) { +/** + * Draws the shaded regions when "fillGraph" is set. Not to be confused with + * error bars. + * + * @private + */ +DygraphCanvasRenderer.prototype.drawFillBars_ = function(points) { + var ctx = this.elementContext; + var setNames = this.layout.setNames; + var setCount = setNames.length; + var fillAlpha = this.attr_('fillAlpha'); + var stepPlot = this.attr_('stepPlot'); + var stackedGraph = this.attr_("stackedGraph"); + + var baseline = {}; // for stacked graphs: baseline for filling + var currBaseline; + + // 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.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 iter = Dygraph.createIterator(points, firstIndexInSet, setLength, + DygraphCanvasRenderer._getIteratorPredicate( + this.attr_("connectSeparatedPoints"))); // setup graphics context - context.save(); - var point = this.layout.points[0]; - var pointSize = this.dygraph_.attr_("pointSize"); - var prevX = null, prevY = null; - var drawPoints = this.dygraph_.attr_("drawPoints"); - var points = this.layout.points; - for (var j = 0; j < points.length; j++) { - var point = points[j]; - if (point.name == setName) { - if (!isOK(point.canvasy)) { - // this will make us move to the next point, not draw a line to it. - prevX = prevY = null; + var prevX = NaN; + var prevYs = [-1, -1]; + var newYs; + 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 + ',' + fillAlpha + ')'; + ctx.fillStyle = err_color; + ctx.beginPath(); + while(iter.hasNext) { + var point = iter.next(); + if (!Dygraph.isOK(point.y)) { + prevX = NaN; + continue; + } + if (stackedGraph) { + currBaseline = baseline[point.canvasx]; + var lastY; + if (currBaseline === undefined) { + lastY = axisY; } 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))); - - if (!prevX) { - prevX = point.canvasx; - prevY = point.canvasy; + if(stepPlot) { + lastY = currBaseline[0]; } else { - ctx.beginPath(); - ctx.strokeStyle = color; - ctx.lineWidth = this.options.strokeWidth; - ctx.moveTo(prevX, prevY); - if (stepPlot) { - ctx.lineTo(point.canvasx, prevY); - } - prevX = point.canvasx; - prevY = point.canvasy; - ctx.lineTo(prevX, prevY); - ctx.stroke(); + 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; + } - if (drawPoints || isIsolated) { - ctx.beginPath(); - ctx.fillStyle = color; - ctx.arc(point.canvasx, point.canvasy, pointSize, - 0, 2 * Math.PI, false); - ctx.fill(); + } 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 = newYs; + prevX = point.canvasx; } + ctx.fill(); } - - context.restore(); };