-// 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
* - error bars
* - dygraphs attribute system
- *
- * High level overview of classes:
- *
- * - DygraphLayout
- * This contains all the data to be charted.
- * It uses data coordinates, but also records the chart range (in data
- * coordinates) and hence is able to calculate percentage positions ('In
- * this view, Point A lies 25% down the x-axis.')
- * Two things that it does not do are:
- * 1. Record pixel coordinates for anything.
- * 2. (oddly) determine anything about the layout of chart elements.
- * The naming is a vestige of Dygraph's original PlotKit roots.
- *
- * - DygraphCanvasRenderer
- * This class determines the charting area (in pixel coordinates), maps the
- * percentage coordinates in the DygraphLayout to pixels and draws them.
- * It's also responsible for creating chart DOM elements, i.e. annotations,
- * tick mark labels, the title and the x/y-axis labels.
*/
/**
- * Creates a new DygraphLayout object.
- * @return {Object} The DygraphLayout object
- */
-DygraphLayout = function(dygraph) {
- this.dygraph_ = dygraph;
- this.datasets = new Array();
- this.annotations = new Array();
- this.yAxes_ = null;
-
- // TODO(danvk): it's odd that xTicks_ and yTicks_ are inputs, but xticks and
- // yticks are outputs. Clean this up.
- this.xTicks_ = null;
- this.yTicks_ = null;
-};
-
-DygraphLayout.prototype.attr_ = function(name) {
- return this.dygraph_.attr_(name);
-};
-
-DygraphLayout.prototype.addDataset = function(setname, set_xy) {
- this.datasets[setname] = set_xy;
-};
-
-DygraphLayout.prototype.setAnnotations = function(ann) {
- // The Dygraph object's annotations aren't parsed. We parse them here and
- // save a copy. If there is no parser, then the user must be using raw format.
- this.annotations = [];
- var parse = this.attr_('xValueParser') || function(x) { return x; };
- for (var i = 0; i < ann.length; i++) {
- var a = {};
- if (!ann[i].xval && !ann[i].x) {
- this.dygraph_.error("Annotations must have an 'x' property");
- return;
- }
- if (ann[i].icon &&
- !(ann[i].hasOwnProperty('width') &&
- ann[i].hasOwnProperty('height'))) {
- this.dygraph_.error("Must set width and height when setting " +
- "annotation.icon property");
- return;
- }
- Dygraph.update(a, ann[i]);
- if (!a.xval) a.xval = parse(a.x);
- this.annotations.push(a);
- }
-};
-
-DygraphLayout.prototype.setXTicks = function(xTicks) {
- this.xTicks_ = xTicks;
-};
-
-// TODO(danvk): add this to the Dygraph object's API or move it into Layout.
-DygraphLayout.prototype.setYAxes = function (yAxes) {
- this.yAxes_ = yAxes;
-};
-
-DygraphLayout.prototype.setDateWindow = function(dateWindow) {
- this.dateWindow_ = dateWindow;
-};
-
-DygraphLayout.prototype.evaluate = function() {
- this._evaluateLimits();
- this._evaluateLineCharts();
- this._evaluateLineTicks();
- this._evaluateAnnotations();
-};
-
-DygraphLayout.prototype._evaluateLimits = function() {
- this.minxval = this.maxxval = null;
- if (this.dateWindow_) {
- this.minxval = this.dateWindow_[0];
- this.maxxval = this.dateWindow_[1];
- } else {
- for (var name in this.datasets) {
- if (!this.datasets.hasOwnProperty(name)) continue;
- var series = this.datasets[name];
- if (series.length > 1) {
- 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);
-
- for (var i = 0; i < this.yAxes_.length; i++) {
- var axis = this.yAxes_[i];
- axis.minyval = axis.computedValueRange[0];
- axis.maxyval = axis.computedValueRange[1];
- axis.yrange = axis.maxyval - axis.minyval;
- axis.yscale = (axis.yrange != 0 ? 1.0 / axis.yrange : 1.0);
-
- if (axis.g.attr_("logscale")) {
- axis.ylogrange = Dygraph.log10(axis.maxyval) - Dygraph.log10(axis.minyval);
- axis.ylogscale = (axis.ylogrange != 0 ? 1.0 / axis.ylogrange : 1.0);
- if (!isFinite(axis.ylogrange) || isNaN(axis.ylogrange)) {
- axis.g.error('axis ' + i + ' of graph at ' + axis.g +
- ' can\'t be displayed in log scale for range [' +
- axis.minyval + ' - ' + axis.maxyval + ']');
- }
- }
- }
-};
-
-DygraphLayout.prototype._evaluateLineCharts = function() {
- // add all the rects
- this.points = new Array();
- for (var setName in this.datasets) {
- if (!this.datasets.hasOwnProperty(setName)) continue;
-
- var dataset = this.datasets[setName];
- var axis = this.dygraph_.axisPropertiesForSeries(setName);
-
- for (var j = 0; j < dataset.length; j++) {
- var item = dataset[j];
-
- var yval;
- if (axis.logscale) {
- yval = 1.0 - ((Dygraph.log10(parseFloat(item[1])) - Dygraph.log10(axis.minyval)) * axis.ylogscale); // really should just be yscale.
- } else {
- yval = 1.0 - ((parseFloat(item[1]) - axis.minyval) * axis.yscale);
- }
- var point = {
- // TODO(danvk): here
- x: ((parseFloat(item[0]) - this.minxval) * this.xscale),
- y: yval,
- xval: parseFloat(item[0]),
- yval: parseFloat(item[1]),
- name: setName
- };
-
- this.points.push(point);
- }
- }
-};
-
-DygraphLayout.prototype._evaluateLineTicks = function() {
- this.xticks = new Array();
- for (var i = 0; i < this.xTicks_.length; i++) {
- var tick = this.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.yAxes_.length; i++ ) {
- var axis = this.yAxes_[i];
- for (var j = 0; j < axis.ticks.length; j++) {
- var tick = axis.ticks[j];
- var label = tick.label;
- var pos = this.dygraph_.toPercentYCoord(tick.v, i);
- if ((pos >= 0.0) && (pos <= 1.0)) {
- this.yticks.push([i, pos, label]);
- }
- }
- }
-};
-
-
-/**
- * Behaves the same way as PlotKit.Layout, but also copies the errors
- * @private
- */
-DygraphLayout.prototype.evaluateWithError = function() {
- this.evaluate();
- if (!(this.attr_('errorBars') || this.attr_('customBars'))) return;
-
- // Copy over the error terms
- var i = 0; // index in this.points
- for (var setName in this.datasets) {
- if (!this.datasets.hasOwnProperty(setName)) continue;
- var j = 0;
- var dataset = this.datasets[setName];
- for (var j = 0; j < dataset.length; j++, i++) {
- var item = dataset[j];
- var xv = parseFloat(item[0]);
- var yv = parseFloat(item[1]);
-
- if (xv == this.points[i].xval &&
- yv == this.points[i].yval) {
- this.points[i].errorMinus = parseFloat(item[2]);
- this.points[i].errorPlus = parseFloat(item[3]);
- }
- }
- }
-};
-
-DygraphLayout.prototype._evaluateAnnotations = function() {
- // Add the annotations to the point to which they belong.
- // Make a map from (setName, xval) to annotation for quick lookups.
- var annotations = {};
- for (var i = 0; i < this.annotations.length; i++) {
- var a = this.annotations[i];
- annotations[a.xval + "," + a.series] = a;
- }
-
- this.annotated_points = [];
- for (var i = 0; i < this.points.length; i++) {
- var p = this.points[i];
- var k = p.xval + "," + p.name;
- if (k in annotations) {
- p.annotation = annotations[k];
- this.annotated_points.push(p);
- }
- }
-};
-
-/**
- * Convenience function to remove all the data sets from a graph
- */
-DygraphLayout.prototype.removeAllDatasets = function() {
- delete this.datasets;
- this.datasets = new Array();
-};
-
-/**
- * Return a copy of the point at the indicated index, with its yval unstacked.
- * @param int index of point in layout_.points
- */
-DygraphLayout.prototype.unstackPointAtIndex = function(idx) {
- var point = this.points[idx];
-
- // Clone the point since we modify it
- var unstackedPoint = {};
- for (var i in point) {
- unstackedPoint[i] = point[i];
- }
-
- if (!this.attr_("stackedGraph")) {
- return unstackedPoint;
- }
-
- // The unstacked yval is equal to the current yval minus the yval of the
- // next point at the same xval.
- for (var i = idx+1; i < this.points.length; i++) {
- if (this.points[i].xval == point.xval) {
- unstackedPoint.yval -= this.points[i].yval;
- break;
- }
- }
-
- return unstackedPoint;
-}
-
-/**
* 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
*/
DygraphCanvasRenderer = function(dygraph, element, elementContext, layout) {
this.dygraph_ = dygraph;
this.annotations = new Array();
this.chartLabels = {};
- this.area = this.computeArea_();
+ this.area = layout.getPlotArea();
this.container.style.position = "relative";
this.container.style.width = this.width + "px";
return this.dygraph_.attr_(x);
};
-// Compute the box which the chart should be drawn in. This is the canvas's
-// box, less space needed for axis and chart labels.
-// TODO(danvk): this belongs in DygraphLayout.
-DygraphCanvasRenderer.prototype.computeArea_ = function() {
- var area = {
- // TODO(danvk): per-axis setting.
- x: 0,
- y: 0
- };
- if (this.attr_('drawYAxis')) {
- area.x = this.attr_('yAxisLabelWidth') + 2 * this.attr_('axisTickSize');
- }
-
- area.w = this.width - area.x - this.attr_('rightGap');
- area.h = this.height;
- if (this.attr_('drawXAxis')) {
- area.h -= this.attr_('axisLabelFontSize') + 2 * this.attr_('axisTickSize');
- }
-
- // Shrink the drawing area to accomodate additional y-axes.
- if (this.dygraph_.numAxes() == 2) {
- // TODO(danvk): per-axis setting.
- area.w -= (this.attr_('yAxisLabelWidth') + 2 * this.attr_('axisTickSize'));
- } else if (this.dygraph_.numAxes() > 2) {
- this.dygraph_.error("Only two y-axes are supported at this time. (Trying " +
- "to use " + this.dygraph_.numAxes() + ")");
- }
-
- // Add space for chart labels: title, xlabel and ylabel.
- if (this.attr_('title')) {
- area.h -= this.attr_('titleHeight');
- area.y += this.attr_('titleHeight');
- }
- if (this.attr_('xlabel')) {
- area.h -= this.attr_('xLabelHeight');
- }
- if (this.attr_('ylabel')) {
- // It would make sense to shift the chart here to make room for the y-axis
- // label, but the default yAxisLabelWidth is large enough that this results
- // in overly-padded charts. The y-axis label should fit fine. If it
- // doesn't, the yAxisLabelWidth option can be increased.
- }
-
- return area;
-};
-
DygraphCanvasRenderer.prototype.clear = function() {
if (this.isIE) {
// VML takes a while to start up, so we just poll every this.IEDelay
// Do the ordinary rendering, as before
this._renderLineChart();
this._renderAxis();
- this._renderChartLabels();
+ this._renderChartLabels();
this._renderAnnotations();
};
zIndex: 10,
color: this.attr_('axisLabelColor'),
width: this.attr_('axisLabelWidth') + "px",
+ // height: this.attr_('axisLabelFontSize') + 2 + "px",
+ lineHeight: "normal", // Something other than "normal" line-height screws up label positioning.
overflow: "hidden"
};
- var makeDiv = function(txt, axis) {
+ var makeDiv = function(txt, axis, prec_axis) {
var div = document.createElement("div");
for (var name in labelStyle) {
if (labelStyle.hasOwnProperty(name)) {
}
}
var inner_div = document.createElement("div");
- // TODO(danvk): separate class for secondary y-axis
- inner_div.className = 'dygraph-axis-label dygraph-axis-label-' + axis;
+ inner_div.className = 'dygraph-axis-label' +
+ ' dygraph-axis-label-' + axis +
+ (prec_axis ? ' dygraph-axis-label-' + prec_axis : '');
inner_div.appendChild(document.createTextNode(txt));
div.appendChild(inner_div);
return div;
if (this.attr_('drawYAxis')) {
if (this.layout.yticks && this.layout.yticks.length > 0) {
+ var num_axes = this.dygraph_.numAxes();
for (var i = 0; i < this.layout.yticks.length; i++) {
var tick = this.layout.yticks[i];
if (typeof(tick) == "function") return;
var x = this.area.x;
var 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';
}
var y = this.area.y + tick[1] * this.area.h;
context.beginPath();
context.closePath();
context.stroke();
- var label = makeDiv(tick[2], 'y');
+ var label = makeDiv(tick[2], 'y', num_axes == 2 ? prec_axis : null);
var top = (y - this.attr_('axisLabelFontSize') / 2);
if (top < 0) top = 0;
* Overrides the CanvasRenderer method to draw error bars
*/
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 fillGraph = this.attr_("fillGraph");
var stackedGraph = this.attr_("stackedGraph");
var stepPlot = this.attr_("stepPlot");
+ var points = this.layout.points;
+ var pointsLength = points.length;
var setNames = [];
for (var name in this.layout.datasets) {
// Update Points
// TODO(danvk): here
- for (var i = 0; i < this.layout.points.length; i++) {
- var point = this.layout.points[i];
+ for (var i = pointsLength; 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;
}
fillAlpha + ')';
ctx.fillStyle = err_color;
ctx.beginPath();
- for (var j = 0; j < this.layout.points.length; j++) {
- var point = this.layout.points[j];
+ for (var j = 0; j < pointsLength; j++) {
+ var point = points[j];
if (point.name == setName) {
if (!Dygraph.isOK(point.y)) {
prevX = NaN;
// TODO(danvk): here
if (stepPlot) {
- var newYs = [ prevY - point.errorPlus * yscale,
- prevY + point.errorMinus * yscale ];
+ var newYs = [ point.y_bottom, point.y_top ];
prevY = point.y;
} else {
- var newYs = [ point.y - point.errorPlus * yscale,
- point.y + point.errorMinus * yscale ];
+ var 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;
fillAlpha + ')';
ctx.fillStyle = err_color;
ctx.beginPath();
- for (var j = 0; j < this.layout.points.length; j++) {
- var point = this.layout.points[j];
+ for (var j = 0; j < pointsLength; j++) {
+ var point = points[j];
if (point.name == setName) {
if (!Dygraph.isOK(point.y)) {
prevX = NaN;
}
}
- for (var i = 0; i < setCount; i++) {
+ // Drawing the lines.
+ var firstIndexInSet = 0;
+ var afterLastIndexInSet = 0;
+ var setLength = 0;
+ for (var i = 0; i < setCount; i += 1) {
+ setLength = this.layout.setPointsLengths[i];
+ afterLastIndexInSet += setLength;
var setName = setNames[i];
var color = this.colors[setName];
var strokeWidth = this.dygraph_.attr_("strokeWidth", setName);
// setup graphics context
context.save();
- var point = this.layout.points[0];
var pointSize = this.dygraph_.attr_("pointSize", setName);
var prevX = null, prevY = null;
var drawPoints = this.dygraph_.attr_("drawPoints", setName);
- var points = this.layout.points;
- for (var j = 0; j < points.length; j++) {
+ for (var j = firstIndexInSet; j < afterLastIndexInSet; j++) {
var point = points[j];
- if (point.name == setName) {
- if (!Dygraph.isOK(point.canvasy)) {
- if (stepPlot && prevX != null) {
- // Draw a horizontal line to the start of the missing data
+ 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');
+ ctx.moveTo(prevX, prevY);
+ ctx.lineTo(point.canvasx, prevY);
+ ctx.stroke();
+ }
+ // this will make us move to the next point, not draw a line to it.
+ prevX = prevY = null;
+ } 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;
+ } 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 = this.attr_('strokeWidth');
+ ctx.lineWidth = strokeWidth;
ctx.moveTo(prevX, prevY);
- ctx.lineTo(point.canvasx, prevY);
- ctx.stroke();
- }
- // this will make us move to the next point, not draw a line to it.
- prevX = prevY = null;
- } 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 ||
- !Dygraph.isOK(points[j+1].canvasy)));
-
- if (!prevX) {
+ if (stepPlot) {
+ ctx.lineTo(point.canvasx, prevY);
+ }
prevX = point.canvasx;
prevY = point.canvasy;
- } else {
- // TODO(danvk): figure out why this conditional is necessary.
- if (strokeWidth) {
- ctx.beginPath();
- ctx.strokeStyle = color;
- ctx.lineWidth = strokeWidth;
- ctx.moveTo(prevX, prevY);
- if (stepPlot) {
- ctx.lineTo(point.canvasx, prevY);
- }
- prevX = point.canvasx;
- prevY = point.canvasy;
- ctx.lineTo(prevX, prevY);
- ctx.stroke();
- }
+ ctx.lineTo(prevX, prevY);
+ ctx.stroke();
}
+ }
- if (drawPoints || isIsolated) {
- ctx.beginPath();
- ctx.fillStyle = color;
- ctx.arc(point.canvasx, point.canvasy, pointSize,
- 0, 2 * Math.PI, false);
- ctx.fill();
- }
+ if (drawPoints || isIsolated) {
+ ctx.beginPath();
+ ctx.fillStyle = color;
+ ctx.arc(point.canvasx, point.canvasy, pointSize,
+ 0, 2 * Math.PI, false);
+ ctx.fill();
}
}
}
+ firstIndexInSet = afterLastIndexInSet;
}
context.restore();