X-Git-Url: https://adrianiainlam.tk/git/?a=blobdiff_plain;f=dygraph-canvas.js;h=887c6ff68a2650c8c8838ee020d3def7014e798f;hb=0f20de1c01823dd14dadff582c264a05605ee67b;hp=c0d142f34aa0f9c1e32e4f8234adf67732c63c8b;hpb=79253bd07d1fd37d53e0793c08030df4aaf871be;p=dygraphs.git diff --git a/dygraph-canvas.js b/dygraph-canvas.js index c0d142f..887c6ff 100644 --- a/dygraph-canvas.js +++ b/dygraph-canvas.js @@ -29,6 +29,23 @@ "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 {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. + */ 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"; @@ -79,6 +91,12 @@ 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) { @@ -100,30 +118,12 @@ 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 { @@ -145,70 +145,14 @@ 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_); - } - - 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(); - } - } - - 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. - context.beginPath(); - context.moveTo(halfUp(this.area.x), halfDown(this.area.y)); - context.lineTo(halfUp(this.area.x), halfDown(this.area.y + this.area.h)); - context.closePath(); - context.stroke(); - - // if there's a secondary y-axis, draw a vertical line for that, too. - if (this.dygraph_.numAxes() == 2) { - context.beginPath(); - context.moveTo(halfDown(this.area.x + this.area.w), halfDown(this.area.y)); - context.lineTo(halfDown(this.area.x + this.area.w), halfDown(this.area.y + this.area.h)); - context.closePath(); - context.stroke(); - } - } - if (this.attr_('drawXAxis')) { - if (this.layout.xticks) { - for (i = 0; i < this.layout.xticks.length; i++) { - tick = this.layout.xticks[i]; - x = this.area.x + tick[0] * this.area.w; - y = this.area.y + this.area.h; - - /* Tick marks are currently clipped, so don't bother drawing them. - context.beginPath(); - context.moveTo(halfUp(x), halfDown(y)); - context.lineTo(halfUp(x), halfDown(y + this.attr_('axisTickSize'))); - context.closePath(); - context.stroke(); - */ - - label = makeDiv(tick[1], 'x'); - label.style.textAlign = "center"; - label.style.top = (y + this.attr_('axisTickSize')) + 'px'; - - var left = (x - this.attr_('axisLabelWidth')/2); - if (left + this.attr_('axisLabelWidth') > this.width) { - left = this.width - this.attr_('xAxisLabelWidth'); - label.style.textAlign = "right"; - } - if (left < 0) { - left = 0; - label.style.textAlign = "left"; - } +/** + * 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; +}; - label.style.left = left + "px"; - label.style.width = this.attr_('xAxisLabelWidth') + "px"; - this.container.appendChild(label); - this.xlabels.push(label); - } - } +DygraphCanvasRenderer._predicateThatSkipsEmptyPoints = + function(array, idx) { + return array[idx].yval !== null; +}; - context.beginPath(); - context.moveTo(halfUp(this.area.x), halfDown(this.area.y + this.area.h)); - context.lineTo(halfUp(this.area.x + this.area.w), halfDown(this.area.y + this.area.h)); - context.closePath(); - context.stroke(); +/** + * + * @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); - context.restore(); -}; - + var iter = Dygraph.createIterator(points, firstIndexInSet, setLength, + DygraphCanvasRenderer._getIteratorPredicate( + this.attr_("connectSeparatedPoints"))); -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; + 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 = this._drawSeries(ctx, iter, strokeWidth, pointSize, drawPoints, drawGapPoints, stepPlot, color); + this._drawPointsOnLine(ctx, pointsOnLine, drawPointCallback, setName, 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(); }; - -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 ); +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++; } - }; - }; - - // 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) { - continue; - } - - var a = p.annotation; - var tick_height = 6; - if (a.hasOwnProperty("tickHeight")) { - tick_height = a.tickHeight; + if (i == iter.end_) break; } - var div = document.createElement("div"); - for (var name in annotationStyle) { - if (annotationStyle.hasOwnProperty(name)) { - div.style[name] = annotationStyle[name]; + 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); } - } - if (!a.hasOwnProperty('icon')) { - div.className = "dygraphDefaultAnnotation"; - } - if (a.hasOwnProperty('cssClass')) { - div.className += " " + a.cssClass; - } - - var width = a.hasOwnProperty('width') ? a.width : 16; - var height = a.hasOwnProperty('height') ? a.height : 16; - if (a.hasOwnProperty('icon')) { - var img = document.createElement("img"); - img.src = a.icon; - img.width = width; - img.height = height; - div.appendChild(img); - } else if (p.annotation.hasOwnProperty('shortText')) { - div.appendChild(document.createTextNode(p.annotation.shortText)); - } - div.style.left = (p.canvasx - width / 2) + "px"; - if (a.attachAtBottom) { - div.style.top = (this.area.h - height - tick_height) + "px"; - } else { - div.style.top = (p.canvasy - height - tick_height) + "px"; - } - div.style.width = width + "px"; - div.style.height = height + "px"; - div.title = p.annotation.text; - div.style.color = this.colors[p.name]; - div.style.borderColor = this.colors[p.name]; - a.div = div; - - Dygraph.addEvent(div, 'click', - bindEvt('clickHandler', 'annotationClickHandler', p, this)); - Dygraph.addEvent(div, 'mouseover', - bindEvt('mouseOverHandler', 'annotationMouseOverHandler', p, this)); - Dygraph.addEvent(div, 'mouseout', - bindEvt('mouseOutHandler', 'annotationMouseOutHandler', p, 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); + prevCanvasX = prevCanvasY = null; } else { - ctx.moveTo(p.canvasx, this.area.h); - ctx.lineTo(p.canvasx, this.area.h - 2 - tick_height); + 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; + } + } + } + + 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; } - ctx.closePath(); - ctx.stroke(); + first = false; } + ctx.stroke(); + return pointsOnLine; }; +DygraphCanvasRenderer.prototype._drawLine = function(ctx, i) { + var setNames = this.layout.setNames; + var setName = setNames[i]; + + var strokeWidth = this.dygraph_.attr_("strokeWidth", setName); + var borderWidth = this.dygraph_.attr_("strokeBorderWidth", setName); + var drawPointCallback = this.dygraph_.attr_("drawPointCallback", setName) || + Dygraph.Circles.DEFAULT; + + if (borderWidth && strokeWidth) { + this._drawStyledLine(ctx, i, setName, + this.dygraph_.attr_("strokeBorderColor", setName), + strokeWidth + 2 * borderWidth, + this.dygraph_.attr_("strokePattern", setName), + this.dygraph_.attr_("drawPoints", setName), + drawPointCallback, + this.dygraph_.attr_("pointSize", setName)); + } + + this._drawStyledLine(ctx, i, setName, + this.colors[setName], + strokeWidth, + this.dygraph_.attr_("strokePattern", setName), + this.dygraph_.attr_("drawPoints", setName), + drawPointCallback, + this.dygraph_.attr_("pointSize", setName)); +}; /** * Actually draw the lines chart, including error bars. - * TODO(danvk): split this into several smaller functions. * @private */ DygraphCanvasRenderer.prototype._renderLineChart = function() { - var isNullOrNaN = function(x) { - return (x === null || isNaN(x)); - }; - - // TODO(danvk): use this.attr_ for many of these. - var context = this.elementContext; - var fillAlpha = this.attr_('fillAlpha'); + var ctx = this.elementContext; var errorBars = this.attr_("errorBars") || this.attr_("customBars"); var fillGraph = this.attr_("fillGraph"); - var stackedGraph = this.attr_("stackedGraph"); - var stepPlot = this.attr_("stepPlot"); - var points = this.layout.points; - var pointsLength = points.length; - var point, i, j, prevX, prevY, prevYs, color, setName, newYs, err_color, rgb, yscale, axis; + var i; - var setNames = []; - for (var name in this.layout.datasets) { - if (this.layout.datasets.hasOwnProperty(name)) { - setNames.push(name); - } - } + var setNames = this.layout.setNames; var setCount = setNames.length; - // 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 - for (i = pointsLength; i--;) { - point = 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 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 (i = 0; i < setCount; i++) { - setName = setNames[i]; - axis = this.dygraph_.axisPropertiesForSeries(setName); - color = this.colors[setName]; - - // setup graphics context - ctx.save(); - 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 = 0; j < pointsLength; j++) { - point = points[j]; - if (point.name == setName) { - if (!Dygraph.isOK(point.y)) { - prevX = NaN; - continue; - } - - // TODO(danvk): here - if (stepPlot) { - newYs = [ point.y_bottom, point.y_top ]; - prevY = point.y; - } else { - newYs = [ point.y_bottom, point.y_top ]; - } - newYs[0] = this.area.h * newYs[0] + this.area.y; - newYs[1] = this.area.h * newYs[1] + this.area.y; - if (!isNaN(prevX)) { - if (stepPlot) { - ctx.moveTo(prevX, newYs[0]); - } else { - ctx.moveTo(prevX, prevYs[0]); - } - ctx.lineTo(point.canvasx, newYs[0]); - ctx.lineTo(point.canvasx, newYs[1]); - if (stepPlot) { - ctx.lineTo(prevX, newYs[1]); - } else { - ctx.lineTo(prevX, prevYs[1]); - } - ctx.closePath(); - } - prevYs = newYs; - prevX = point.canvasx; - } - } - ctx.fill(); - } + ctx.save(); + this.drawErrorBars_(points); + ctx.restore(); } else if (fillGraph) { - var baseline = []; // for stacked graphs: baseline for filling - - // 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; - - // setup graphics context - ctx.save(); - 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 = 0; j < pointsLength; j++) { - point = points[j]; - if (point.name == setName) { - if (!Dygraph.isOK(point.y)) { - prevX = NaN; - continue; - } - if (stackedGraph) { - var 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; - } - } - ctx.fill(); - } + ctx.save(); + this.drawFillBars_(points); + ctx.restore(); } // Drawing the lines. - var firstIndexInSet = 0; - var afterLastIndexInSet = 0; - var setLength = 0; for (i = 0; i < setCount; i += 1) { - setLength = this.layout.setPointsLengths[i]; - afterLastIndexInSet += setLength; - setName = setNames[i]; - color = this.colors[setName]; - var strokeWidth = this.dygraph_.attr_("strokeWidth", setName); + 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 - context.save(); - var pointSize = this.dygraph_.attr_("pointSize", setName); - prevX = null; - prevY = null; - var drawPoints = this.dygraph_.attr_("drawPoints", setName); - var strokePattern = this.dygraph_.attr_("strokePattern", setName); - if (!Dygraph.isArrayLike(strokePattern)) { - strokePattern = null; - } - for (j = firstIndexInSet; j < afterLastIndexInSet; j++) { - point = points[j]; - if (isNullOrNaN(point.canvasy)) { - if (stepPlot && prevX !== null) { - // Draw a horizontal line to the start of the missing data - ctx.beginPath(); - ctx.strokeStyle = color; - ctx.lineWidth = this.attr_('strokeWidth'); - this._dashedLine(ctx, prevX, prevY, point.canvasx, prevY, strokePattern); - ctx.stroke(); - } - // this will make us move to the next point, not draw a line to it. - prevX = prevY = null; + 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 { - // A point is "isolated" if it is non-null but both the previous - // and next points are null. - var isIsolated = (!prevX && (j == points.length - 1 || - isNullOrNaN(points[j+1].canvasy))); - if (prevX === null) { - prevX = point.canvasx; - prevY = point.canvasy; + 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 { - // Skip over points that will be drawn in the same pixel. - if (Math.round(prevX) == Math.round(point.canvasx) && - Math.round(prevY) == Math.round(point.canvasy)) { - continue; - } - // TODO(antrob): skip over points that lie on a line that is already - // going to be drawn. There is no need to have more than 2 - // consecutive points that are collinear. - if (strokeWidth) { - ctx.beginPath(); - ctx.strokeStyle = color; - ctx.lineWidth = strokeWidth; - if (stepPlot) { - this._dashedLine(ctx, prevX, prevY, point.canvasx, prevY, strokePattern); - } - this._dashedLine(ctx, prevX, prevY, point.canvasx, point.canvasy, strokePattern); - prevX = point.canvasx; - prevY = point.canvasy; - ctx.stroke(); - } + ctx.moveTo(prevX, prevYs[0]); } - - if (drawPoints || isIsolated) { - ctx.beginPath(); - ctx.fillStyle = color; - ctx.arc(point.canvasx, point.canvasy, pointSize, - 0, 2 * Math.PI, false); - ctx.fill(); + 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; } - firstIndexInSet = afterLastIndexInSet; + ctx.fill(); } - - context.restore(); }; /** - * 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. + * Draws the shaded regions when "fillGraph" is set. Not to be confused with + * error bars. + * * @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.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"); - // If we have a different dash pattern than the last time this was called we - // reset our dash history and start the pattern from the begging - // regardless of state of the last pattern. - if (!Dygraph.compareArrays(pattern, this._dashedLineToHistoryPattern)) { - this._dashedLineToHistoryPattern = pattern; - this._dashedLineToHistory = [0, 0]; - } - ctx.save(); + 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"))); - // Calculate transformation parameters - dx = (x2-x); - dy = (y2-y); - len = Math.sqrt(dx*dx + dy*dy); - rot = Math.atan2(dy, dx); - - // Set transformation - ctx.translate(x, y); - ctx.moveTo(0, 0); - ctx.rotate(rot); - - // Set last pattern index we used for this pattern. - patternIndex = this._dashedLineToHistory[0]; - x = 0; - while (len > x) { - // Get the length of the pattern segment we are dealing with. - segment = pattern[patternIndex]; - // If our last draw didn't complete the pattern segment all the way we - // will try to finish it. Otherwise we will try to do the whole segment. - if (this._dashedLineToHistory[1]) { - x += this._dashedLineToHistory[1]; - } else { - x += segment; - } - if (x > len) { - // We were unable to complete this pattern index all the way, keep - // where we are the history so our next draw continues where we left off - // in the pattern. - this._dashedLineToHistory = [patternIndex, x-len]; - x = len; - } else { - // We completed this patternIndex, we put in the history that we are on - // the beginning of the next segment. - this._dashedLineToHistory = [(patternIndex+1)%pattern.length, 0]; - } + // setup graphics context + 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 { + if(stepPlot) { + lastY = currBaseline[0]; + } else { + lastY = currBaseline; + } + } + newYs = [ point.canvasy, lastY ]; - // We do a line on a even pattern index and just move on a odd pattern index. - // The move is the empty space in the dash. - if(patternIndex % 2 === 0) { - ctx.lineTo(x, 0); - } else { - ctx.moveTo(x, 0); + if(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; } - // If we are not done, next loop process the next pattern segment, or the - // first segment again if we are at the end of the pattern. - patternIndex = (patternIndex+1) % pattern.length; + ctx.fill(); } - ctx.restore(); };