-// Copyright 2006 Dan Vanderkam (danvdk@gmail.com)
-// All Rights Reserved.
+/**
+ * @license
+ * Copyright 2006 Dan Vanderkam (danvdk@gmail.com)
+ * MIT-licensed (http://opensource.org/licenses/MIT)
+ */
/**
- * @fileoverview Based on PlotKit, but modified to meet the needs of dygraphs.
+ * @fileoverview Based on PlotKit.CanvasRenderer, but modified to meet the
+ * needs of dygraphs.
+ *
* In particular, support for:
- * - grid overlays
+ * - grid overlays
* - error bars
* - dygraphs attribute system
*/
/**
- * Creates a new DygraphLayout object.
- * @param {Object} options Options for PlotKit.Layout
- * @return {Object} The DygraphLayout object
- */
-DygraphLayout = function(dygraph, options) {
- this.dygraph_ = dygraph;
- this.options = {}; // TODO(danvk): remove, use attr_ instead.
- MochiKit.Base.update(this.options, options ? options : {});
- this.datasets = new Array();
-};
-
-DygraphLayout.prototype.attr_ = function(name) {
- return this.dygraph_.attr_(name);
-};
-
-DygraphLayout.prototype.addDataset = function(setname, set_xy) {
- this.datasets[setname] = set_xy;
-};
-
-DygraphLayout.prototype.evaluate = function() {
- this._evaluateLimits();
- this._evaluateLineCharts();
- this._evaluateLineTicks();
-};
-
-DygraphLayout.prototype._evaluateLimits = function() {
- this.minxval = this.maxxval = null;
- for (var name in this.datasets) {
- var series = this.datasets[name];
- var x1 = series[0][0];
- if (!this.minxval || x1 < this.minxval) this.minxval = x1;
-
- var x2 = series[series.length - 1][0];
- if (!this.maxxval || x2 > this.maxxval) this.maxxval = x2;
- }
- this.xrange = this.maxxval - this.minxval;
- this.xscale = (this.xrange != 0 ? 1/this.xrange : 1.0);
-
- this.minyval = this.options.yAxis[0];
- this.maxyval = this.options.yAxis[1];
- this.yrange = this.maxyval - this.minyval;
- this.yscale = (this.yrange != 0 ? 1/this.yrange : 1.0);
-};
-
-DygraphLayout.prototype._evaluateLineCharts = function() {
- // add all the rects
- this.points = new Array();
- for (var setName in this.datasets) {
- var dataset = this.datasets[setName];
- for (var j = 0; j < dataset.length; j++) {
- var item = dataset[j];
- var point = {
- 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;
- }
- if ((point.x >= 0.0) && (point.x <= 1.0)) {
- this.points.push(point);
- }
- }
- }
-};
-
-DygraphLayout.prototype._evaluateLineTicks = function() {
- this.xticks = new Array();
- for (var i = 0; i < this.options.xTicks.length; i++) {
- var tick = this.options.xTicks[i];
- var label = tick.label;
- var pos = this.xscale * (tick.v - this.minxval);
- if ((pos >= 0.0) && (pos <= 1.0)) {
- this.xticks.push([pos, label]);
- }
- }
-
- this.yticks = new Array();
- for (var i = 0; i < this.options.yTicks.length; i++) {
- var tick = this.options.yTicks[i];
- var label = tick.label;
- var pos = 1.0 - (this.yscale * (tick.v - this.minyval));
- if ((pos >= 0.0) && (pos <= 1.0)) {
- this.yticks.push([pos, label]);
- }
- }
-};
-
-
-/**
- * Behaves the same way as PlotKit.Layout, but also copies the errors
- * @private
- */
-DygraphLayout.prototype.evaluateWithError = function() {
- this.evaluate();
- if (!this.options.errorBars) return;
-
- // Copy over the error terms
- var i = 0; // index in this.points
- for (var setName in this.datasets) {
- var j = 0;
- var dataset = this.datasets[setName];
- for (var j = 0; j < dataset.length; j++, i++) {
- var item = dataset[j];
- var xv = parseFloat(item[0]);
- var yv = parseFloat(item[1]);
-
- if (xv == this.points[i].xval &&
- yv == this.points[i].yval) {
- this.points[i].errorMinus = parseFloat(item[2]);
- this.points[i].errorPlus = parseFloat(item[3]);
- }
- }
- }
-};
-
-/**
- * Convenience function to remove all the data sets from a graph
+ * The DygraphCanvasRenderer class does the actual rendering of the chart onto
+ * a canvas. It's based on PlotKit.CanvasRenderer.
+ * @param {Object} element The canvas to attach to
+ * @param {Object} elementContext The 2d context of the canvas (injected so it
+ * can be mocked for testing.)
+ * @param {Layout} layout The DygraphLayout object for this graph.
+ * @constructor
*/
-DygraphLayout.prototype.removeAllDatasets = function() {
- delete this.datasets;
- this.datasets = new Array();
-};
-/**
- * Change the values of various layout options
- * @param {Object} new_options an associative array of new properties
- */
-DygraphLayout.prototype.updateOptions = function(new_options) {
- MochiKit.Base.update(this.options, new_options ? new_options : {});
-};
+/*jshint globalstrict: true */
+/*global Dygraph:false,RGBColor:false */
+"use strict";
-// Subclass PlotKit.CanvasRenderer to add:
-// 1. X/Y grid overlay
-// 2. Ability to draw error bars (if required)
/**
- * Sets some PlotKit.CanvasRenderer options
- * @param {Object} element The canvas to attach to
- * @param {Layout} layout The DygraphLayout object for this graph.
- * @param {Object} options Options to pass on to CanvasRenderer
+ * @constructor
+ *
+ * This gets called when there are "new points" to chart. This is generally the
+ * case when the underlying data being charted has changed. It is _not_ called
+ * in the common case that the user has zoomed or is panning the view.
+ *
+ * The chart canvas has already been created by the Dygraph object. The
+ * renderer simply gets a drawing context.
+ *
+ * @param {Dyraph} dygraph The chart to which this renderer belongs.
+ * @param {Canvas} element The <canvas> DOM element on which to draw.
+ * @param {CanvasRenderingContext2D} elementContext The drawing context.
+ * @param {DygraphLayout} layout The chart's DygraphLayout object.
+ *
+ * TODO(danvk): remove the elementContext property.
*/
-DygraphCanvasRenderer = function(dygraph, element, layout, options) {
- // TODO(danvk): remove options, just use dygraph.attr_.
+var DygraphCanvasRenderer = function(dygraph, element, elementContext, layout) {
this.dygraph_ = dygraph;
- // default options
- this.options = {
- "strokeWidth": 0.5,
- "drawXAxis": true,
- "drawYAxis": true,
- "axisLineColor": Color.blackColor(),
- "axisLineWidth": 0.5,
- "axisTickSize": 3,
- "axisLabelColor": Color.blackColor(),
- "axisLabelFont": "Arial",
- "axisLabelFontSize": 9,
- "axisLabelWidth": 50,
- "drawYGrid": true,
- "drawXGrid": true,
- "gridLineColor": MochiKit.Color.Color.grayColor()
- };
- MochiKit.Base.update(this.options, options);
-
this.layout = layout;
- this.element = MochiKit.DOM.getElement(element);
+ this.element = element;
+ this.elementContext = elementContext;
this.container = this.element.parentNode;
- // Stuff relating to Canvas on IE support
- this.isIE = (/MSIE/.test(navigator.userAgent) && !window.opera);
-
- if (this.isIE && !isNil(G_vmlCanvasManager)) {
- this.IEDelay = 0.5;
- this.maxTries = 5;
- this.renderDelay = null;
- this.clearDelay = null;
- this.element = G_vmlCanvasManager.initElement(this.element);
- }
-
this.height = this.element.height;
this.width = this.element.width;
throw "Canvas is not supported.";
// internal state
- this.xlabels = new Array();
- this.ylabels = new Array();
+ this.area = layout.getPlotArea();
+ this.container.style.position = "relative";
+ this.container.style.width = this.width + "px";
+
+ // Set up a clipping area for the canvas (and the interaction canvas).
+ // This ensures that we don't overdraw.
+ if (this.dygraph_.isUsingExcanvas_) {
+ this._createIEClipArea();
+ } else {
+ // on Android 3 and 4, setting a clipping area on a canvas prevents it from
+ // displaying anything.
+ if (!Dygraph.isAndroid()) {
+ var ctx = this.dygraph_.canvas_ctx_;
+ ctx.beginPath();
+ ctx.rect(this.area.x, this.area.y, this.area.w, this.area.h);
+ ctx.clip();
- 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;
+ ctx = this.dygraph_.hidden_ctx_;
+ ctx.beginPath();
+ ctx.rect(this.area.x, this.area.y, this.area.w, this.area.h);
+ ctx.clip();
+ }
+ }
+};
- MochiKit.DOM.updateNodeAttributes(this.container,
- {"style":{ "position": "relative", "width": this.width + "px"}});
+/**
+ * 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) {
// VML takes a while to start up, so we just poll every this.IEDelay
try {
this.clearDelay.cancel();
this.clearDelay = null;
}
- var context = this.element.getContext("2d");
+ context = this.elementContext;
}
catch (e) {
- this.clearDelay = MochiKit.Async.wait(this.IEDelay);
- this.clearDelay.addCallback(bind(this.clear, this));
+ // 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;
}
}
- var context = this.element.getContext("2d");
+ context = this.elementContext;
context.clearRect(0, 0, this.width, this.height);
-
- MochiKit.Iter.forEach(this.xlabels, MochiKit.DOM.removeElement);
- MochiKit.Iter.forEach(this.ylabels, MochiKit.DOM.removeElement);
- this.xlabels = new Array();
- this.ylabels = new Array();
};
-
+/**
+ * Checks whether the browser supports the <canvas> tag.
+ * @private
+ */
DygraphCanvasRenderer.isSupported = function(canvasName) {
var canvas = null;
try {
- if (MochiKit.Base.isUndefinedOrNull(canvasName))
- canvas = MochiKit.DOM.CANVAS({});
- else
- canvas = MochiKit.DOM.getElement(canvasName);
- var context = canvas.getContext("2d");
+ if (typeof(canvasName) == 'undefined' || canvasName === null) {
+ canvas = document.createElement("canvas");
+ } else {
+ canvas = canvasName;
+ }
+ canvas.getContext("2d");
}
catch (e) {
var ie = navigator.appVersion.match(/MSIE (\d\.\d)/);
};
/**
- * Draw an X/Y grid on top of the existing plot
+ * This method is responsible for drawing everything on the chart, including
+ * lines, error bars, fills and axes.
+ * It is called immediately after clear() on every frame, including during pans
+ * and zooms.
+ * @private
*/
DygraphCanvasRenderer.prototype.render = function() {
- // Draw the new X/Y grid
- var ctx = this.element.getContext("2d");
- if (this.options.drawYGrid) {
- var ticks = this.layout.yticks;
- ctx.save();
- ctx.strokeStyle = this.options.gridLineColor.toRGBString();
- 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();
+ // attaches point.canvas{x,y}
+ this._updatePoints();
+
+ // actually draws the chart.
+ this._renderLineChart();
+};
+
+DygraphCanvasRenderer.prototype._createIEClipArea = function() {
+ var className = 'dygraph-clip-div';
+ var graphDiv = this.dygraph_.graphDiv;
+
+ // Remove old clip divs.
+ for (var i = graphDiv.childNodes.length-1; i >= 0; i--) {
+ if (graphDiv.childNodes[i].className == className) {
+ graphDiv.removeChild(graphDiv.childNodes[i]);
}
}
- if (this.options.drawXGrid) {
- var ticks = this.layout.xticks;
- ctx.save();
- ctx.strokeStyle = this.options.gridLineColor.toRGBString();
- ctx.lineWidth = this.options.axisLineWidth;
- for (var i=0; i<ticks.length; i++) {
- var x = this.area.x + ticks[i][0] * this.area.w;
- var y = this.area.y + this.area.h;
- ctx.beginPath();
- ctx.moveTo(x, y);
- ctx.lineTo(x, this.area.y);
- ctx.closePath();
- ctx.stroke();
+ // Determine background color to give clip divs.
+ var backgroundColor = document.bgColor;
+ var element = this.dygraph_.graphDiv;
+ while (element != document) {
+ var bgcolor = element.currentStyle.backgroundColor;
+ if (bgcolor && bgcolor != 'transparent') {
+ backgroundColor = bgcolor;
+ break;
}
+ element = element.parentNode;
}
- // Do the ordinary rendering, as before
- // TODO(danvk) Call super.render()
- this._renderLineChart();
- this._renderAxis();
+ 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);
+ }
+
+ 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
+ });
};
-DygraphCanvasRenderer.prototype._renderAxis = function() {
- if (!this.options.drawXAxis && !this.options.drawYAxis)
- return;
+/**
+ * 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;
+};
+
+DygraphCanvasRenderer._predicateThatSkipsEmptyPoints =
+ function(array, idx) {
+ return array[idx].yval !== null;
+};
+
+/**
+ * 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"); // TODO(danvk): per-series
+ if (!Dygraph.isArrayLike(strokePattern)) {
+ strokePattern = null;
+ }
+
+ 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?
+
+ var stroking = strokePattern && (strokePattern.length >= 2);
- var context = this.element.getContext("2d");
+ var ctx = e.drawingContext;
+ ctx.save();
+ if (stroking) {
+ ctx.installPattern(strokePattern);
+ }
+
+ var pointsOnLine = DygraphCanvasRenderer._drawSeries(
+ e, iter, strokeWidth, pointSize, drawPoints, drawGapPoints, stepPlot, color);
+ DygraphCanvasRenderer._drawPointsOnLine(
+ e, pointsOnLine, drawPointCallback, color, pointSize);
+
+ if (stroking) {
+ ctx.uninstallPattern();
+ }
- var labelStyle = {"style":
- {"position": "absolute",
- "fontSize": this.options.axisLabelFontSize + "px",
- "zIndex": 10,
- "color": this.options.axisLabelColor.toRGBString(),
- "width": this.options.axisLabelWidth + "px",
- "overflow": "hidden"
+ 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
+
+ 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++;
+ }
+ if (i == limit) break;
+ point = arr[i];
}
- };
- // axis lines
- context.save();
- context.strokeStyle = this.options.axisLineColor.toRGBString();
- context.lineWidth = this.options.axisLineWidth;
-
-
- if (this.options.drawYAxis) {
- if (this.layout.yticks) {
- var drawTick = function(tick) {
- 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 = DIV(labelStyle, tick[1]);
- var top = (y - this.options.axisLabelFontSize / 2);
- if (top < 0) top = 0;
-
- if (top + this.options.axisLabelFontSize + 3 > this.height) {
- label.style.bottom = "0px";
- } else {
- label.style.top = top + "px";
+ 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;
+ var peek = 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;
+ }
}
- label.style.left = "0px";
- label.style.textAlign = "right";
- label.style.width = this.options.yAxisLabelWidth + "px";
- MochiKit.DOM.appendChildNodes(this.container, label);
- this.ylabels.push(label);
- };
-
- MochiKit.Iter.forEach(this.layout.yticks, bind(drawTick, this));
-
- // 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";
}
- }
- 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();
- }
+ if (prevCanvasX !== null) {
+ if (strokeWidth) {
+ if (stepPlot) {
+ ctx.moveTo(prevCanvasX, prevCanvasY);
+ ctx.lineTo(point.canvasx, prevCanvasY);
+ }
- if (this.options.drawXAxis) {
- if (this.layout.xticks) {
- var drawTick = function(tick) {
- 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 = DIV(labelStyle, 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";
+ ctx.lineTo(point.canvasx, point.canvasy);
}
+ } else {
+ 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;
+};
- label.style.left = left + "px";
- label.style.width = this.options.xAxisLabelWidth + "px";
- MochiKit.DOM.appendChildNodes(this.container, label);
- this.xlabels.push(label);
- };
+/**
+ * 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);
+ ctx.restore();
+ }
+};
- MochiKit.Iter.forEach(this.layout.xticks, bind(drawTick, this));
+/**
+ * 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;
}
+ }
+};
+
+/**
+ * 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(opt_seriesName, opt_ctx) {
+ var ctx = opt_ctx || this.elementContext;
+ var errorBars = this.attr_("errorBars") || this.attr_("customBars");
+ var fillGraph = this.attr_("fillGraph");
+ var i;
+
+ var sets = this.layout.points;
+ var setNames = this.layout.setNames;
+ var setCount = setNames.length;
+ var setName;
+
+ this.colors = this.dygraph_.colorsMap_;
+
+ // Determine which series have specialized plotters.
+ var plotter_attr = this.attr_("plotter");
+ var plotters = plotter_attr;
+ if (!Dygraph.isArrayLike(plotters)) {
+ plotters = [plotters];
+ }
+
+ 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.
+
+ setPlotters[setName] = setPlotter;
+ }
+
+ for (i = 0; i < plotters.length; i++) {
+ var plotter = plotters[i];
+ var is_last = (i == plotters.length - 1);
+
+ for (var j = 0; j < sets.length; j++) {
+ setName = setNames[j];
+ if (opt_seriesName && setName != opt_seriesName) continue;
+
+ var points = sets[j];
+
+ // 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;
+ }
+ }
- 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();
+ 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,
+ allSeriesPoints: sets
+ });
+ ctx.restore();
+ }
}
+};
+
+/**
+ * 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);
+ },
- context.restore();
+ errorPlotter: function(e) {
+ DygraphCanvasRenderer._errorPlotter(e);
+ }
};
+/**
+ * Plotter which draws the central lines for a series.
+ * @private
+ */
+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 (borderWidth && strokeWidth) {
+ DygraphCanvasRenderer._drawStyledLine(e,
+ g.getOption("strokeBorderColor", setName),
+ strokeWidth + 2 * borderWidth,
+ strokePattern,
+ drawPoints,
+ drawPointCallback,
+ pointSize
+ );
+ }
+
+ DygraphCanvasRenderer._drawStyledLine(e,
+ e.color,
+ strokeWidth,
+ strokePattern,
+ drawPoints,
+ drawPointCallback,
+ pointSize
+ );
+};
/**
- * Overrides the CanvasRenderer method to draw error bars
+ * 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._renderLineChart = function() {
- var context = this.element.getContext("2d");
- var colorCount = this.options.colorScheme.length;
- var colorScheme = this.options.colorScheme;
- var setNames = MochiKit.Base.keys(this.layout.datasets);
- var errorBars = this.layout.options.errorBars;
- var setCount = setNames.length;
- var bind = MochiKit.Base.bind;
- var partial = MochiKit.Base.partial;
+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");
+ }
- //Update Points
- var updatePoint = function(point) {
- point.canvasx = this.area.w * point.x + this.area.x;
- point.canvasy = this.area.h * point.y + this.area.y;
+ var ctx = e.drawingContext;
+ var color = e.color;
+ var fillAlpha = g.getOption('fillAlpha', setName);
+ var stepPlot = g.getOption('stepPlot'); // TODO(danvk): per-series
+ var axis = e.axis;
+ 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];
+ 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();
+
+ 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 (stepPlot) {
+ newYs = [ point.y_bottom, point.y_top ];
+ prevY = point.y;
+ } else {
+ 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;
}
- MochiKit.Iter.forEach(this.layout.points, updatePoint, this);
-
- // create paths
- var isOK = function(x) { return x && !isNaN(x); };
- var makePath = function(ctx) {
- for (var i = 0; i < setCount; i++) {
- var setName = setNames[i];
- var color = colorScheme[i%colorCount];
- var strokeX = this.options.strokeColorTransform;
-
- // setup graphics context
- context.save();
- context.strokeStyle = color.toRGBString();
- context.lineWidth = this.options.strokeWidth;
- 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;
+ 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) {
+ // 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 stepPlot = g.getOption('stepPlot');
+ var stackedGraph = g.getOption("stackedGraph");
+ var colors = g.getColors();
+
+ var baseline = {}; // for stacked graphs: baseline for filling
+ var currBaseline;
+
+ // 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 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;
+ 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 {
- // 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;
- } else {
- ctx.beginPath();
- ctx.moveTo(prevX, prevY);
- prevX = point.canvasx;
- prevY = point.canvasy;
- ctx.lineTo(prevX, prevY);
- ctx.stroke();
- }
-
- if (drawPoints || isIsolated) {
- ctx.beginPath();
- ctx.fillStyle = color.toRGBString();
- ctx.arc(point.canvasx, point.canvasy, pointSize, 0, 360, false);
- ctx.fill();
- }
+ lastY = currBaseline;
}
}
- }
- }
- };
+ newYs = [ point.canvasy, lastY ];
- var makeErrorBars = function(ctx) {
- for (var i = 0; i < setCount; i++) {
- var setName = setNames[i];
- var color = colorScheme[i % colorCount];
- var strokeX = this.options.strokeColorTransform;
-
- // setup graphics context
- context.save();
- context.strokeStyle = color.toRGBString();
- context.lineWidth = this.options.strokeWidth;
- var prevX = -1;
- var prevYs = [-1, -1];
- var count = 0;
- var yscale = this.layout.yscale;
- var errorTrapezoid = function(ctx_,point) {
- count++;
- if (point.name == setName) {
- if (!point.y || isNaN(point.y)) {
- prevX = -1;
- return;
+ 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] ];
}
- 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();
+ } 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]);
}
- prevYs[0] = newYs[0];
- prevYs[1] = newYs[1];
- prevX = point.canvasx;
+ } else {
+ ctx.lineTo(point.canvasx, newYs[0]);
+ ctx.lineTo(point.canvasx, newYs[1]);
}
- };
- // should be same color as the lines
- var err_color = color.colorWithAlpha(0.15);
- ctx.fillStyle = err_color.toRGBString();
- ctx.beginPath();
- MochiKit.Iter.forEach(this.layout.points, partial(errorTrapezoid, ctx), this);
- ctx.fill();
- }
- };
- if (errorBars)
- bind(makeErrorBars, this)(context);
- bind(makePath, this)(context);
- context.restore();
+ ctx.lineTo(prevX, prevYs[1]);
+ ctx.closePath();
+ }
+ prevYs = newYs;
+ prevX = point.canvasx;
+ }
+ ctx.fill();
+ }
};