X-Git-Url: https://adrianiainlam.tk/git/?a=blobdiff_plain;f=dygraph-canvas.js;h=2824003ffd8ebfdad5810a0c3fbaeea35eb9d76d;hb=7b00a3cd1eedf449f0d08f63efc544ffb566ed08;hp=f19e7a3d53394b59a47ec83511adaeb9d3c8c784;hpb=b843b52c15b95e0f97a172e67da0a3b865d1d5ee;p=dygraphs.git diff --git a/dygraph-canvas.js b/dygraph-canvas.js index f19e7a3..2824003 100644 --- a/dygraph-canvas.js +++ b/dygraph-canvas.js @@ -25,10 +25,27 @@ */ /*jshint globalstrict: true */ -/*global Dygraph:false,RGBColor:false */ +/*global Dygraph:false,RGBColorParser: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 {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. + */ var DygraphCanvasRenderer = function(dygraph, element, elementContext, layout) { this.dygraph_ = dygraph; @@ -45,11 +62,6 @@ var DygraphCanvasRenderer = function(dygraph, element, elementContext, layout) { 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"; @@ -75,10 +87,21 @@ var DygraphCanvasRenderer = function(dygraph, element, elementContext, layout) { } }; -DygraphCanvasRenderer.prototype.attr_ = function(x) { - return this.dygraph_.attr_(x); +/** + * This just forwards to dygraph.attr_. + * TODO(danvk): remove this? + * @private + */ +DygraphCanvasRenderer.prototype.attr_ = function(name, opt_seriesName) { + return this.dygraph_.attr_(name, opt_seriesName); }; +/** + * 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) { @@ -100,30 +123,12 @@ DygraphCanvasRenderer.prototype.clear = function() { 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 = {}; }; - +/** + * Checks whether the browser supports the <canvas> tag. + * @private + */ DygraphCanvasRenderer.isSupported = function(canvasName) { var canvas = null; try { @@ -145,72 +150,18 @@ DygraphCanvasRenderer.isSupported = function(canvasName) { }; /** - * @param { [String] } colors Array of color strings. Should have one entry for - * each series to be rendered. - */ -DygraphCanvasRenderer.prototype.setColors = function(colors) { - this.colorScheme_ = colors; -}; - -/** - * Draw an X/Y grid on top of the existing plot + * 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. 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_); - } + // attaches point.canvas{x,y} + this._updatePoints(); - 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.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.attr_('drawXGrid')) { - ticks = this.layout.xticks; - ctx.save(); - ctx.strokeStyle = this.attr_('gridLineColor'); - ctx.lineWidth = this.attr_('gridLineWidth'); - for (i=0; i 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. - var axisX; - if (this.attr_('drawAxesAtZero')) { - var r = this.dygraph_.toPercentXCoord(0); - if (r > 1 || r < 0) r = 0; - axisX = halfUp(this.area.x + r * this.area.w); - } else { - axisX = halfUp(this.area.x); - } - context.beginPath(); - context.moveTo(axisX, halfDown(this.area.y)); - context.lineTo(axisX, 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(); - } - } +/** + * 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; +}; - 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"; - } +DygraphCanvasRenderer._predicateThatSkipsEmptyPoints = + function(array, idx) { + return array[idx].yval !== null; +}; - label.style.left = left + "px"; - label.style.width = this.attr_('xAxisLabelWidth') + "px"; - this.container.appendChild(label); - this.xlabels.push(label); - } - } +/** + * 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._drawStyledLine = function(e, + color, strokeWidth, strokePattern, drawPoints, + drawPointCallback, pointSize) { + var g = e.dygraph; + // TODO(konigsberg): Compute attributes outside this method call. + var stepPlot = g.getOption("stepPlot", e.setName); - context.beginPath(); - var axisY; - if (this.attr_('drawAxesAtZero')) { - var r = this.dygraph_.toPercentYCoord(0, 0); - if (r > 1 || r < 0) r = 1; - axisY = halfDown(this.area.y + r * this.area.h); - } else { - axisY = halfDown(this.area.y + this.area.h); - } - context.moveTo(halfUp(this.area.x), axisY); - context.lineTo(halfUp(this.area.x + this.area.w), axisY); - context.closePath(); - context.stroke(); + if (!Dygraph.isArrayLike(strokePattern)) { + strokePattern = null; } - context.restore(); -}; + var drawGapPoints = g.getOption('drawGapEdgePoints', e.setName); + var points = e.points; + var iter = Dygraph.createIterator(points, 0, points.length, + DygraphCanvasRenderer._getIteratorPredicate( + g.getOption("connectSeparatedPoints"))); // TODO(danvk): per-series? -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; - } + var stroking = strokePattern && (strokePattern.length >= 2); - 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 ctx = e.drawingContext; + ctx.save(); + if (stroking) { + ctx.installPattern(strokePattern); } - 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'; - } + var pointsOnLine = DygraphCanvasRenderer._drawSeries( + e, iter, strokeWidth, pointSize, drawPoints, drawGapPoints, stepPlot, color); + DygraphCanvasRenderer._drawPointsOnLine( + e, pointsOnLine, drawPointCallback, color, pointSize); - class_div = document.createElement("div"); - class_div.className = classes; - class_div.innerHTML = html; - - inner_div.appendChild(class_div); - div.appendChild(inner_div); - return div; + if (stroking) { + ctx.uninstallPattern(); } - 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; - } + ctx.restore(); }; +/** + * 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 -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 ctx = e.drawingContext; + ctx.beginPath(); + ctx.strokeStyle = color; + ctx.lineWidth = strokeWidth; - 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(); - } -}; + // 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_; -DygraphCanvasRenderer.makeNextPointStep_ = function( - connect, points, start, end) { - if (connect) { - return function(j) { - while (++j + start < end) { - if (!(points[start + j].yval === null)) break; + for (var i = iter.start_; i < limit; i++) { + point = arr[i]; + if (predicate) { + while (i < limit && !predicate(arr, i)) { + i++; } - return j; + if (i == limit) break; + point = arr[i]; } - } else { - return function(j) { return j + 1 }; - } -}; -var _isNullOrNaN = function(x) { - return (x === null || isNaN(x)); -}; - -DygraphCanvasRenderer.prototype._drawStyledLine = function( - ctx, i, setName, color, strokeWidth, strokePattern, drawPoints, - drawPointCallback, pointSize) { - 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); - - ctx.save(); - if (strokeWidth && !stepPlot && (!strokePattern || strokePattern.length <= 1)) { - this._drawTrivialLine(ctx, points, setLength, firstIndexInSet, setName, color, strokeWidth, drawPointCallback, pointSize, drawPoints, drawGapPoints); - } else { - this._drawNonTrivialLine(ctx, points, setLength, firstIndexInSet, setName, color, strokeWidth, strokePattern, drawPointCallback, pointSize, drawPoints, drawGapPoints, stepPlot); - } - ctx.restore(); -}; - -DygraphCanvasRenderer.prototype._drawNonTrivialLine = function( - ctx, points, setLength, firstIndexInSet, setName, color, strokeWidth, strokePattern, drawPointCallback, pointSize, drawPoints, drawGapPoints, stepPlot) { - var prevX = null; - var prevY = null; - var nextY = null; - var point, nextPoint; - var pointsOnLine = []; // Array of [canvasx, canvasy] pairs. - var next = DygraphCanvasRenderer.makeNextPointStep_( - this.attr_('connectSeparatedPoints'), points, firstIndexInSet, - firstIndexInSet + setLength); - for (var j = 0; j < setLength; j = next(j)) { - point = points[firstIndexInSet + j]; - nextY = (next(j) < setLength) ? - points[firstIndexInSet + next(j)].canvasy : null; - if (_isNullOrNaN(point.canvasy)) { - if (stepPlot && prevX !== null) { + if (point.canvasy === null || point.canvasy != point.canvasy) { + if (stepPlot && prevCanvasX !== 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(); + ctx.moveTo(prevCanvasX, prevCanvasY); + ctx.lineTo(point.canvasx, prevCanvasY); } - // this will make us move to the next point, not draw a line to it. - prevX = prevY = null; + prevCanvasX = prevCanvasY = null; } else { - // A point is "isolated" if it is non-null but both the previous - // and next points are null. - var isIsolated = (!prevX && _isNullOrNaN(nextY)); - if (drawGapPoints) { - // Also consider a point to be is "isolated" if it's adjacent to a - // null point, excluding the graph edges. - if ((j > 0 && !prevX) || - (next(j) < setLength && _isNullOrNaN(nextY))) { - isIsolated = true; + 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; + } } } - 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 (prevCanvasX !== null) { if (strokeWidth) { - ctx.beginPath(); - ctx.strokeStyle = color; - ctx.lineWidth = strokeWidth; if (stepPlot) { - this._dashedLine(ctx, prevX, prevY, point.canvasx, prevY, strokePattern); - prevX = point.canvasx; + ctx.moveTo(prevCanvasX, prevCanvasY); + ctx.lineTo(point.canvasx, prevCanvasY); } - 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(); - } -}; -DygraphCanvasRenderer.prototype._drawTrivialLine = function( - ctx, points, setLength, firstIndexInSet, setName, color, strokeWidth, drawPointCallback, pointSize, drawPoints, drawGapPoints) { - var prevX = null; - var prevY = null; - var nextY = null; - var pointsOnLine = []; // Array of [canvasx, canvasy] pairs. - ctx.beginPath(); - ctx.strokeStyle = color; - ctx.lineWidth = strokeWidth; - for (var j = firstIndexInSet; j < firstIndexInSet + setLength; ++j) { - var point = points[j]; - nextY = (j + 1 < firstIndexInSet + setLength) ? points[j + 1].canvasy : null; - if (_isNullOrNaN(point.canvasy)) { - prevX = prevY = null; - } else { - var isIsolated = (!prevX && _isNullOrNaN(nextY)); - if (drawGapPoints) { - // Also consider a point to be is "isolated" if it's adjacent to a - // null point, excluding the graph edges. - if ((j > firstIndexInSet && !prevX) || - ((j + 1 < firstIndexInSet + setLength) && _isNullOrNaN(nextY))) { - isIsolated = true; - } - } - if (prevX === null) { - prevX = point.canvasx; - prevY = point.canvasy; - if (j === firstIndexInSet) { - ctx.moveTo(point.canvasx, point.canvasy); + ctx.lineTo(point.canvasx, point.canvasy); } } else { - ctx.lineTo(point.canvasx, point.canvasy); + ctx.moveTo(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; +}; + +/** + * 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( - this.dygraph_, setName, ctx, cb[0], cb[1], color, pointSize); + e.dygraph, e.setName, ctx, cb[0], cb[1], color, pointSize); 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)); +/** + * Attaches canvas coordinates to the points array. + * @private + */ +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; + } } - - 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)); }; /** - * Actually draw the lines chart, including error bars. - * TODO(danvk): split this into several smaller functions. + * Add canvas Actually draw the lines chart, including error bars. + * If opt_seriesName is specified, only that series will be drawn. + * (This is used for expedited redrawing with highlightSeriesOpts) + * Lines are typically drawn in the non-interactive dygraph canvas. If opt_ctx + * is specified, they can be drawn elsewhere. + * + * This function can only be called if DygraphLayout's points array has been + * updated with canvas{x,y} attributes, i.e. by + * DygraphCanvasRenderer._updatePoints. * @private */ -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; +DygraphCanvasRenderer.prototype._renderLineChart = function(opt_seriesName, opt_ctx) { + var ctx = opt_ctx || this.elementContext; + var i; + var sets = this.layout.points; var setNames = this.layout.setNames; - var setCount = setNames.length; + var setName; - // 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]; - } + this.colors = this.dygraph_.colorsMap_; - // 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. - 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; + // Determine which series have specialized plotters. + var plotter_attr = this.attr_("plotter"); + var plotters = plotter_attr; + if (!Dygraph.isArrayLike(plotters)) { + plotters = [plotters]; } - // create paths - if (errorBars) { - ctx.save(); - if (fillGraph) { - this.dygraph_.warn("Can't use fillGraph option with error bars"); - } + var setPlotters = {}; // series name -> plotter fn. + for (i = 0; i < setNames.length; i++) { + setName = setNames[i]; + var setPlotter = this.attr_("plotter", setName); + if (setPlotter == plotter_attr) continue; // not specialized. - for (i = 0; i < setCount; i++) { - setName = setNames[i]; - axis = this.dygraph_.axisPropertiesForSeries(setName); - color = this.colors[setName]; + setPlotters[setName] = setPlotter; + } - var firstIndexInSet = this.layout.setPointsOffsets[i]; - var setLength = this.layout.setPointsLengths[i]; - var afterLastIndexInSet = firstIndexInSet + setLength; + for (i = 0; i < plotters.length; i++) { + var plotter = plotters[i]; + var is_last = (i == plotters.length - 1); - var next = DygraphCanvasRenderer.makeNextPointStep_( - this.attr_('connectSeparatedPoints'), points, - afterLastIndexInSet); + for (var j = 0; j < sets.length; j++) { + setName = setNames[j]; + if (opt_seriesName && setName != opt_seriesName) continue; - // setup graphics context - 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(); - 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; - } + var points = sets[j]; - // 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; + // Only throw in the specialized plotters on the last iteration. + var p = plotter; + if (setName in setPlotters) { + if (is_last) { + p = setPlotters[setName]; + } else { + // Don't use the standard plotters in this case. + continue; } } - 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 next = DygraphCanvasRenderer.makeNextPointStep_( - this.attr_('connectSeparatedPoints'), points, - afterLastIndexInSet); - - // setup graphics context - 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 = newYs; - prevX = point.canvasx; - } - } - ctx.fill(); + var color = this.colors[setName]; + var strokeWidth = this.dygraph_.getOption("strokeWidth", setName); + + 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(); } - ctx.restore(); } +}; - // Drawing the lines. - for (i = 0; i < setCount; i += 1) { - this._drawLine(ctx, i); +/** + * 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); + }, + + fillPlotter: function(e) { + DygraphCanvasRenderer._fillPlotter(e); + }, + + errorPlotter: function(e) { + DygraphCanvasRenderer._errorPlotter(e); } }; /** - * 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. + * Plotter which draws the central lines for a series. * @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; - } +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.getOption("strokeBorderWidth", setName); + var drawPointCallback = g.getOption("drawPointCallback", setName) || + Dygraph.Circles.DEFAULT; + var strokePattern = g.getOption("strokePattern", setName); + var drawPoints = g.getOption("drawPoints", setName); + var pointSize = g.getOption("pointSize", setName); - // 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]; + if (borderWidth && strokeWidth) { + DygraphCanvasRenderer._drawStyledLine(e, + g.getOption("strokeBorderColor", setName), + strokeWidth + 2 * borderWidth, + strokePattern, + drawPoints, + drawPointCallback, + pointSize + ); } - 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; + 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.getOption("errorBars") || g.getOption("customBars"); + if (!errorBars) return; + + var fillGraph = g.getOption("fillGraph", setName); + if (fillGraph) { + g.warn("Can't use fillGraph option with error bars"); + } + + var ctx = e.drawingContext; + var color = e.color; + var fillAlpha = g.getOption('fillAlpha', setName); + var stepPlot = g.getOption("stepPlot", setName); + var points = e.points; + + var iter = Dygraph.createIterator(points, 0, points.length, + DygraphCanvasRenderer._getIteratorPredicate( + g.getOption("connectSeparatedPoints"))); + + 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 = new RGBColorParser(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)); + }; + + while (iter.hasNext) { + var point = iter.next(); + if ((!stepPlot && isNullUndefinedOrNaN(point.y)) || + (stepPlot && !isNaN(prevY) && isNullUndefinedOrNaN(prevY))) { + prevX = NaN; + continue; } - 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; + + if (stepPlot) { + newYs = [ point.y_bottom, point.y_top ]; + prevY = point.y; } 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]; + newYs = [ point.y_bottom, point.y_top ]; + } + 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.lineTo(prevX, prevYs[1]); + ctx.closePath(); } + prevYs = newYs; + prevX = point.canvasx; + } + ctx.fill(); +}; - // 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); +/** + * 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); + } + + var anySeriesFilled = (function() { + for (var i = 0; i < setNames.length; i++) { + if (g.getOption("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.getOption('fillAlpha'); + var stackedGraph = g.getOption("stackedGraph"); + var colors = g.getColors(); + + var baseline = {}; // for stacked graphs: baseline for filling + 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.getOption('fillGraph', setName)) continue; + + var stepPlot = g.getOption('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.getOption("connectSeparatedPoints"))); + + // setup graphics context + var prevX = NaN; + var prevYs = [-1, -1]; + var newYs; + // should be same color as the lines but only 15% opaque. + var rgb = new RGBColorParser(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; + 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 { + if(prevStepPlot) { + 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]); + + // 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; } - // 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; + prevStepPlot = stepPlot; + ctx.fill(); } - ctx.restore(); };