X-Git-Url: https://adrianiainlam.tk/git/?a=blobdiff_plain;f=dygraph-canvas.js;h=6bf5fbcb457e187bb089ce0b93f395e1d9d6423f;hb=bacf5ce283d6871ce1c090f29bf5411341622248;hp=45c02ffc8f34e1598614dc03529b4740b2c31ea6;hpb=9ac5e4aea125e706201c61b0ccb13a2cafe5618f;p=dygraphs.git diff --git a/dygraph-canvas.js b/dygraph-canvas.js index 45c02ff..6bf5fbc 100644 --- a/dygraph-canvas.js +++ b/dygraph-canvas.js @@ -1,626 +1,788 @@ -// 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 + * 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 + */ + +/*jshint globalstrict: true */ +/*global Dygraph:false */ +"use strict"; + + +/** + * @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 {Dygraph} dygraph The chart to which this renderer belongs. + * @param {HTMLCanvasElement} 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. */ -DygraphLayout = function(dygraph, options) { +var DygraphCanvasRenderer = function(dygraph, element, elementContext, layout) { 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); -}; + this.layout = layout; + this.element = element; + this.elementContext = elementContext; + this.container = this.element.parentNode; -DygraphLayout.prototype.addDataset = function(setname, set_xy) { - this.datasets[setname] = set_xy; -}; + this.height = this.element.height; + this.width = this.element.width; -DygraphLayout.prototype.evaluate = function() { - this._evaluateLimits(); - this._evaluateLineCharts(); - this._evaluateLineTicks(); -}; + // --- check whether everything is ok before we return + // NOTE(konigsberg): isIE is never defined in this object. Bug of some sort. + if (!this.isIE && !(Dygraph.isCanvasSupported(this.element))) + throw "Canvas is not supported."; -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]; + // internal state + 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 { - 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; + // 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(); } } - 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; +/** + * 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 { + if (this.clearDelay) { + this.clearDelay.cancel(); + this.clearDelay = null; } - // if ((point.x >= 0.0) && (point.x <= 1.0)) { - this.points.push(point); - // } + 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); +}; + +/** + * 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() { + // attaches point.canvas{x,y} + this._updatePoints(); + + // actually draws the chart. + this._renderLineChart(); }; -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]); +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]); } } - 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]); + // 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; } -}; - -/** - * 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]); - } + 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); } -}; -/** - * Convenience function to remove all the data sets from a graph - */ -DygraphLayout.prototype.removeAllDatasets = function() { - delete this.datasets; - this.datasets = new Array(); + 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 + }); }; + /** - * Change the values of various layout options - * @param {Object} new_options an associative array of new properties + * 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. */ -DygraphLayout.prototype.updateOptions = function(new_options) { - Dygraph.update(this.options, new_options ? new_options : {}); +DygraphCanvasRenderer._getIteratorPredicate = function(connectSeparatedPoints) { + return connectSeparatedPoints ? + DygraphCanvasRenderer._predicateThatSkipsEmptyPoints : + null; }; -// Subclass PlotKit.CanvasRenderer to add: -// 1. X/Y grid overlay -// 2. Ability to draw error bars (if required) +DygraphCanvasRenderer._predicateThatSkipsEmptyPoints = + function(array, idx) { + return array[idx].yval !== null; +}; /** - * 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 + * Draws a line with the styles passed in and calls all the drawPointCallbacks. + * @param {Object} e The dictionary passed to the plotter function. + * @private */ -DygraphCanvasRenderer = function(dygraph, element, layout, options) { - // TODO(danvk): remove options, just use dygraph.attr_. - this.dygraph_ = dygraph; +DygraphCanvasRenderer._drawStyledLine = function(e, + color, strokeWidth, strokePattern, drawPoints, + drawPointCallback, pointSize) { + var g = e.dygraph; + // TODO(konigsberg): Compute attributes outside this method call. + var stepPlot = g.getBooleanOption("stepPlot", e.setName); + + if (!Dygraph.isArrayLike(strokePattern)) { + strokePattern = null; + } - // 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, - }; - Dygraph.update(this.options, options); + var drawGapPoints = g.getBooleanOption('drawGapEdgePoints', e.setName); - this.layout = layout; - this.element = element; - this.container = this.element.parentNode; + var points = e.points; + var setName = e.setName; + var iter = Dygraph.createIterator(points, 0, points.length, + DygraphCanvasRenderer._getIteratorPredicate( + g.getBooleanOption("connectSeparatedPoints", setName))); - this.height = this.element.height; - this.width = this.element.width; + var stroking = strokePattern && (strokePattern.length >= 2); - // --- check whether everything is ok before we return - if (!this.isIE && !(DygraphCanvasRenderer.isSupported(this.element))) - throw "Canvas is not supported."; + var ctx = e.drawingContext; + ctx.save(); + if (stroking) { + ctx.installPattern(strokePattern); + } - // internal state - this.xlabels = new Array(); - this.ylabels = new Array(); + var pointsOnLine = DygraphCanvasRenderer._drawSeries( + e, iter, strokeWidth, pointSize, drawPoints, drawGapPoints, stepPlot, color); + DygraphCanvasRenderer._drawPointsOnLine( + e, pointsOnLine, drawPointCallback, color, pointSize); - 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; + if (stroking) { + ctx.uninstallPattern(); + } - this.container.style.position = "relative"; - this.container.style.width = this.width + "px"; + ctx.restore(); }; -DygraphCanvasRenderer.prototype.clear = function() { - 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; +/** + * This does the actual drawing of lines on the canvas, for just one series. + * Returns a list of [canvasx, canvasy] pairs for points for which a + * drawPointCallback should be fired. These include isolated points, or all + * points if drawPoints=true. + * @param {Object} e The dictionary passed to the plotter function. + * @private + */ +DygraphCanvasRenderer._drawSeries = function(e, + 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 + + var ctx = e.drawingContext; + ctx.beginPath(); + ctx.strokeStyle = color; + ctx.lineWidth = strokeWidth; + + // NOTE: we break the iterator's encapsulation here for about a 25% speedup. + var arr = iter.array_; + var limit = iter.end_; + var predicate = iter.predicate_; + + for (var i = iter.start_; i < limit; i++) { + point = arr[i]; + if (predicate) { + while (i < limit && !predicate(arr, i)) { + i++; } - var context = this.element.getContext("2d"); - } - 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; + if (i == limit) break; + point = arr[i]; } - } - var context = this.element.getContext("2d"); - context.clearRect(0, 0, this.width, this.height); + // FIXME: The 'canvasy != canvasy' test here catches NaN values but the test + // doesn't catch Infinity values. Could change this to + // !isFinite(point.canvasy), but I assume it avoids isNaN for performance? + 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(prevCanvasX, prevCanvasY); + ctx.lineTo(point.canvasx, prevCanvasY); + } + prevCanvasX = prevCanvasY = null; + } else { + isIsolated = false; + if (drawGapPoints || !prevCanvasX) { + iter.nextIdx_ = i; + iter.next(); + nextCanvasY = iter.hasNext ? iter.peek.canvasy : null; + + 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; + } + } + } - 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); + if (prevCanvasX !== null) { + if (strokeWidth) { + if (stepPlot) { + ctx.moveTo(prevCanvasX, prevCanvasY); + ctx.lineTo(point.canvasx, prevCanvasY); + } + + ctx.lineTo(point.canvasx, point.canvasy); + } + } else { + ctx.moveTo(point.canvasx, point.canvasy); + } + if (drawPoints || isIsolated) { + pointsOnLine.push([point.canvasx, point.canvasy, point.idx]); + } + prevCanvasX = point.canvasx; + prevCanvasY = point.canvasy; + } + first = false; } - this.xlabels = new Array(); - this.ylabels = new Array(); + ctx.stroke(); + return pointsOnLine; }; - -DygraphCanvasRenderer.isSupported = function(canvasName) { - var canvas = null; - try { - if (typeof(canvasName) == 'undefined' || canvasName == null) - canvas = document.createElement("canvas"); - else - canvas = canvasName; - var context = 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; +/** + * This fires the drawPointCallback functions, which draw dots on the points by + * default. This gets used when the "drawPoints" option is set, or when there + * are isolated points. + * @param {Object} e The dictionary passed to the plotter function. + * @private + */ +DygraphCanvasRenderer._drawPointsOnLine = function( + e, pointsOnLine, drawPointCallback, color, pointSize) { + var ctx = e.drawingContext; + for (var idx = 0; idx < pointsOnLine.length; idx++) { + var cb = pointsOnLine[idx]; + ctx.save(); + drawPointCallback( + e.dygraph, e.setName, ctx, cb[0], cb[1], color, pointSize, cb[2]); + ctx.restore(); } - return true; }; /** - * Draw an X/Y grid on top of the existing plot + * Attaches canvas coordinates to the points array. + * @private */ -DygraphCanvasRenderer.prototype.render = function() { - // Draw the new X/Y grid - var ctx = this.element.getContext("2d"); - 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(); +DygraphCanvasRenderer.prototype._updatePoints = function() { + // Update Points + // TODO(danvk): here + // + // 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. + // NOTE(danvk): this is trickier than it sounds at first. The transformation + // needs to be done before the .moveTo() and .lineTo() calls, but must be + // undone before the .stroke() call to ensure that the stroke width is + // unaffected. An alternative is to reduce the stroke width in the + // transformed coordinate space, but you can't specify different values for + // each dimension (as you can with .scale()). The speedup here is ~12%. + var sets = this.layout.points; + for (var i = sets.length; i--;) { + var points = sets[i]; + for (var j = points.length; j--;) { + var point = points[j]; + point.canvasx = this.area.w * point.x + this.area.x; + point.canvasy = this.area.h * point.y + this.area.y; } } +}; - 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 plotter fn. + for (i = 0; i < setNames.length; i++) { + setName = setNames[i]; + var setPlotter = this.dygraph_.getOption("plotter", setName); + if (setPlotter == plotter_attr) continue; // not specialized. + setPlotters[setName] = setPlotter; + } -DygraphCanvasRenderer.prototype._renderAxis = function() { - if (!this.options.drawXAxis && !this.options.drawYAxis) - return; + for (i = 0; i < plotters.length; i++) { + var plotter = plotters[i]; + var is_last = (i == plotters.length - 1); - var context = this.element.getContext("2d"); + for (var j = 0; j < sets.length; j++) { + setName = setNames[j]; + if (opt_seriesName && setName != opt_seriesName) continue; - var labelStyle = { - "position": "absolute", - "fontSize": this.options.axisLabelFontSize + "px", - "zIndex": 10, - "color": this.options.axisLabelColor, - "width": this.options.axisLabelWidth + "px", - "overflow": "hidden" - }; - var makeDiv = function(txt) { - var div = document.createElement("div"); - for (var name in labelStyle) { - if (labelStyle.hasOwnProperty(name)) { - div.style[name] = labelStyle[name]; - } - } - div.appendChild(document.createTextNode(txt)); - return div; - }; + var points = sets[j]; - // axis lines - context.save(); - context.strokeStyle = this.options.axisLineColor; - context.lineWidth = this.options.axisLineWidth; - - if (this.options.drawYAxis) { - if (this.layout.yticks && this.layout.yticks.length > 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"; + // Only throw in the specialized plotters on the last iteration. + var p = plotter; + if (setName in setPlotters) { + if (is_last) { + p = setPlotters[setName]; } else { - label.style.top = top + "px"; + // Don't use the standard plotters in this case. + continue; } - label.style.left = "0px"; - label.style.textAlign = "right"; - label.style.width = this.options.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.options.axisLabelFontSize; - var bottom = parseInt(bottomTick.style.top) + fontSize; - if (bottom > this.height - fontSize) { - bottomTick.style.top = (parseInt(bottomTick.style.top) - - fontSize / 2) + "px"; - } - } + var color = this.colors[setName]; + var strokeWidth = this.dygraph_.getOption("strokeWidth", setName); - 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(); + ctx.save(); + ctx.strokeStyle = color; + ctx.lineWidth = strokeWidth; + p({ + points: points, + setName: setName, + drawingContext: ctx, + color: color, + strokeWidth: strokeWidth, + dygraph: this.dygraph_, + axis: this.dygraph_.axisPropertiesForSeries(setName), + plotArea: this.area, + seriesIndex: j, + seriesCount: sets.length, + singleSeriesName: opt_seriesName, + allSeriesPoints: sets + }); + ctx.restore(); + } } +}; - 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"; - } +/** + * Standard plotters. These may be used by clients via Dygraph.Plotters. + * See comments there for more details. + */ +DygraphCanvasRenderer._Plotters = { + linePlotter: function(e) { + DygraphCanvasRenderer._linePlotter(e); + }, - label.style.left = left + "px"; - label.style.width = this.options.xAxisLabelWidth + "px"; - this.container.appendChild(label); - this.xlabels.push(label); - } - } + fillPlotter: function(e) { + DygraphCanvasRenderer._fillPlotter(e); + }, - 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(); + errorPlotter: function(e) { + DygraphCanvasRenderer._errorPlotter(e); } - - context.restore(); }; - /** - * Overrides the CanvasRenderer method to draw error bars + * Plotter which draws the central lines for a series. + * @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 setNames = []; - for (var name in this.layout.datasets) { - if (this.layout.datasets.hasOwnProperty(name)) { - setNames.push(name); - } +DygraphCanvasRenderer._linePlotter = function(e) { + var g = e.dygraph; + var setName = e.setName; + var strokeWidth = e.strokeWidth; + + // TODO(danvk): Check if there's any performance impact of just calling + // getOption() inside of _drawStyledLine. Passing in so many parameters makes + // this code a bit nasty. + var borderWidth = g.getNumericOption("strokeBorderWidth", setName); + var drawPointCallback = g.getOption("drawPointCallback", setName) || + Dygraph.Circles.DEFAULT; + var strokePattern = g.getOption("strokePattern", setName); + var drawPoints = g.getBooleanOption("drawPoints", setName); + var pointSize = g.getNumericOption("pointSize", setName); + + if (borderWidth && strokeWidth) { + DygraphCanvasRenderer._drawStyledLine(e, + g.getOption("strokeBorderColor", setName), + strokeWidth + 2 * borderWidth, + strokePattern, + drawPoints, + drawPointCallback, + pointSize + ); } - var setCount = setNames.length; - // Update Points - // TODO(danvk): here - for (var i = 0; i < this.layout.points.length; i++) { - var point = this.layout.points[i]; - point.canvasx = this.area.w * point.x + this.area.x; - point.canvasy = this.area.h * point.y + this.area.y; + DygraphCanvasRenderer._drawStyledLine(e, + e.color, + strokeWidth, + strokePattern, + drawPoints, + drawPointCallback, + pointSize + ); +}; + +/** + * 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._errorPlotter = function(e) { + var g = e.dygraph; + var setName = e.setName; + var errorBars = g.getBooleanOption("errorBars") || + g.getBooleanOption("customBars"); + if (!errorBars) return; + + var fillGraph = g.getBooleanOption("fillGraph", setName); + if (fillGraph) { + Dygraph.warn("Can't use fillGraph option with error bars"); } - // create paths - var isOK = function(x) { return x && !isNaN(x); }; + var ctx = e.drawingContext; + var color = e.color; + var fillAlpha = g.getNumericOption('fillAlpha', setName); + var stepPlot = g.getBooleanOption("stepPlot", setName); + var points = e.points; + + var iter = Dygraph.createIterator(points, 0, points.length, + DygraphCanvasRenderer._getIteratorPredicate( + g.getBooleanOption("connectSeparatedPoints", setName))); + + var newYs; + + // setup graphics context + var prevX = NaN; + var prevY = NaN; + var prevYs = [-1, -1]; + // should be same color as the lines but only 15% opaque. + var rgb = Dygraph.toRGB_(color); + var err_color = + 'rgba(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ',' + fillAlpha + ')'; + ctx.fillStyle = err_color; + ctx.beginPath(); + + var isNullUndefinedOrNaN = function(x) { + return (x === null || + x === undefined || + isNaN(x)); + }; - var ctx = context; - if (errorBars) { - if (fillGraph) { - this.dygraph_.warn("Can't use fillGraph option with error bars"); + while (iter.hasNext) { + var point = iter.next(); + if ((!stepPlot && isNullUndefinedOrNaN(point.y)) || + (stepPlot && !isNaN(prevY) && isNullUndefinedOrNaN(prevY))) { + prevX = NaN; + continue; } - for (var i = 0; i < setCount; i++) { - var setName = setNames[i]; - var color = colorScheme[i % colorCount]; - - // setup graphics context - ctx.save(); - ctx.strokeStyle = color; - ctx.lineWidth = this.options.strokeWidth; - var prevX = -1; - var prevYs = [-1, -1]; - var count = 0; - 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]; - count++; - if (point.name == setName) { - if (!isOK(point.y)) { - prevX = -1; - continue; - } - // TODO(danvk): here - 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(); - } - prevYs[0] = newYs[0]; - prevYs[1] = newYs[1]; - prevX = point.canvasx; - } - } - ctx.fill(); + if (stepPlot) { + newYs = [ point.y_bottom, point.y_top ]; + prevY = point.y; + } else { + newYs = [ point.y_bottom, point.y_top ]; } - } else if (fillGraph) { - // TODO(danvk): merge this code with the logic above; they're very similar. - for (var i = 0; i < setCount; i++) { - var setName = setNames[i]; - var setNameLast; - if (i>0) setNameLast = setNames[i-1]; - var color = colorScheme[i % colorCount]; - - // setup graphics context - ctx.save(); - ctx.strokeStyle = color; - ctx.lineWidth = this.options.strokeWidth; - var prevX = -1; - var prevYs = [-1, -1]; - var count = 0; - 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]; - count++; - if (point.name == setName) { - if (!isOK(point.y)) { - prevX = -1; - continue; - } - var pX = 1.0 + this.layout.minyval * this.layout.yscale; - if (pX < 0.0) pX = 0.0; - else if (pX > 1.0) pX = 1.0; - var newYs = [ point.y, pX ]; - 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(); - } - prevYs[0] = newYs[0]; - prevYs[1] = newYs[1]; - prevX = point.canvasx; - } + newYs[0] = e.plotArea.h * newYs[0] + e.plotArea.y; + newYs[1] = e.plotArea.h * newYs[1] + e.plotArea.y; + if (!isNaN(prevX)) { + if (stepPlot) { + ctx.moveTo(prevX, prevYs[0]); + ctx.lineTo(point.canvasx, prevYs[0]); + ctx.lineTo(point.canvasx, prevYs[1]); + } else { + ctx.moveTo(prevX, prevYs[0]); + ctx.lineTo(point.canvasx, newYs[0]); + ctx.lineTo(point.canvasx, newYs[1]); } - ctx.fill(); + ctx.lineTo(prevX, prevYs[1]); + ctx.closePath(); } + prevYs = newYs; + prevX = point.canvasx; + } + ctx.fill(); +}; + +/** + * Draws the shaded regions when "fillGraph" is set. Not to be confused with + * error bars. + * + * For stacked charts, it's more convenient to handle all the series + * simultaneously. So this plotter plots all the points on the first series + * it's asked to draw, then ignores all the other series. + * + * @private + */ +DygraphCanvasRenderer._fillPlotter = function(e) { + // Skip if we're drawing a single series for interactive highlight overlay. + if (e.singleSeriesName) return; + + // We'll handle all the series at once, not one-by-one. + if (e.seriesIndex !== 0) return; + + var g = e.dygraph; + var setNames = g.getLabels().slice(1); // remove x-axis + + // getLabels() includes names for invisible series, which are not included in + // allSeriesPoints. We remove those to make the two match. + // TODO(danvk): provide a simpler way to get this information. + for (var i = setNames.length; i >= 0; i--) { + if (!g.visibility()[i]) setNames.splice(i, 1); } - for (var i = 0; i < setCount; i++) { - var setName = setNames[i]; - var color = colorScheme[i%colorCount]; + var anySeriesFilled = (function() { + for (var i = 0; i < setNames.length; i++) { + if (g.getBooleanOption("fillGraph", setNames[i])) return true; + } + return false; + })(); + + if (!anySeriesFilled) return; + + var ctx = e.drawingContext; + var area = e.plotArea; + var sets = e.allSeriesPoints; + var setCount = sets.length; + + var fillAlpha = g.getNumericOption('fillAlpha'); + var stackedGraph = g.getBooleanOption("stackedGraph"); + var colors = g.getColors(); + + // For stacked graphs, track the baseline for filling. + // + // The filled areas below graph lines are trapezoids with two + // vertical edges. The top edge is the line segment being drawn, and + // the baseline is the bottom edge. Each baseline corresponds to the + // top line segment from the previous stacked line. In the case of + // step plots, the trapezoids are rectangles. + var baseline = {}; + var currBaseline; + var prevStepPlot; // for different line drawing modes (line/step) per series + + // process sets in reverse order (needed for stacked graphs) + for (var setIdx = setCount - 1; setIdx >= 0; setIdx--) { + var setName = setNames[setIdx]; + if (!g.getBooleanOption('fillGraph', setName)) continue; + + var stepPlot = g.getBooleanOption('stepPlot', setName); + var color = colors[setIdx]; + var axis = g.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 = area.h * axisY + area.y; + + var points = sets[setIdx]; + var iter = Dygraph.createIterator(points, 0, points.length, + DygraphCanvasRenderer._getIteratorPredicate( + g.getBooleanOption("connectSeparatedPoints", setName))); // 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; + // should be same color as the lines but only 15% opaque. + var rgb = Dygraph.toRGB_(color); + var err_color = + 'rgba(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ',' + fillAlpha + ')'; + ctx.fillStyle = err_color; + ctx.beginPath(); + var last_x, is_first = true; + while (iter.hasNext) { + var point = iter.next(); + if (!Dygraph.isOK(point.y)) { + prevX = NaN; + if (point.y_stacked !== null && !isNaN(point.y_stacked)) { + baseline[point.canvasx] = area.h * point.y_stacked + area.y; + } + continue; + } + if (stackedGraph) { + if (!is_first && last_x == point.xval) { + continue; + } else { + is_first = false; + last_x = point.xval; + } + + 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(prevStepPlot) { + lastY = currBaseline[0]; } else { - ctx.beginPath(); - ctx.strokeStyle = color; - ctx.lineWidth = this.options.strokeWidth; - ctx.moveTo(prevX, prevY); - prevX = point.canvasx; - prevY = point.canvasy; - ctx.lineTo(prevX, prevY); - ctx.stroke(); + lastY = currBaseline; } + } + newYs = [ point.canvasy, lastY ]; - if (drawPoints || isIsolated) { - ctx.beginPath(); - ctx.fillStyle = color; - ctx.arc(point.canvasx, point.canvasy, pointSize, - 0, 2 * Math.PI, false); - ctx.fill(); + 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]); + + // Move to top fill point + if (stepPlot) { + ctx.lineTo(point.canvasx, prevYs[0]); + } else { + ctx.lineTo(point.canvasx, newYs[0]); + } + // Move to bottom fill point + if (prevStepPlot && currBaseline) { + // Draw to the bottom of the baseline + ctx.lineTo(point.canvasx, currBaseline[1]); + } else { + ctx.lineTo(point.canvasx, newYs[1]); + } + + ctx.lineTo(prevX, prevYs[1]); + ctx.closePath(); + } + prevYs = newYs; + prevX = point.canvasx; } + prevStepPlot = stepPlot; + ctx.fill(); } - - context.restore(); };