/**
* @fileoverview Based on PlotKit, but modified to meet the needs of dygraphs.
* In particular, support for:
- * - grid overlays
+ * - 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.
*/
/**
this.options = {}; // TODO(danvk): remove, use attr_ instead.
Dygraph.update(this.options, options ? options : {});
this.datasets = new Array();
- this.annotations = new Array()
+ this.annotations = new Array();
};
DygraphLayout.prototype.attr_ = function(name) {
DygraphLayout.prototype.setAnnotations = function(ann) {
// The Dygraph object's annotations aren't parsed. We parse them here and
- // save a copy.
+ // save a copy. If there is no parser, then the user must be using raw format.
this.annotations = [];
- var parse = this.attr_('xValueParser');
+ 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) {
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 + ']');
+ }
+ }
}
};
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: 1.0 - ((parseFloat(item[1]) - axis.minyval) * axis.yscale),
+ y: yval,
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;
- }
this.points.push(point);
}
}
for (var j = 0; j < axis.ticks.length; j++) {
var tick = axis.ticks[j];
var label = tick.label;
- var pos = 1.0 - (axis.yscale * (tick.v - axis.minyval));
+ var pos = this.dygraph_.toPercentYCoord(tick.v, i);
if ((pos >= 0.0) && (pos <= 1.0)) {
this.yticks.push([i, pos, label]);
}
/**
* Sets some PlotKit.CanvasRenderer options
* @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.
* @param {Object} options Options to pass on to CanvasRenderer
*/
-DygraphCanvasRenderer = function(dygraph, element, layout, options) {
+DygraphCanvasRenderer = function(dygraph, element, elementContext, layout,
+ options) {
// TODO(danvk): remove options, just use dygraph.attr_.
this.dygraph_ = dygraph;
this.layout = layout;
this.element = element;
+ this.elementContext = elementContext;
this.container = this.element.parentNode;
this.height = this.element.height;
this.xlabels = new Array();
this.ylabels = new Array();
this.annotations = new Array();
+ this.chartLabels = {};
// TODO(danvk): consider all axes in this computation.
this.area = {
"to use " + this.dygraph_.numAxes() + ")");
}
+ // Add space for chart labels: title, xlabel and ylabel.
+ if (this.attr_('title')) {
+ this.area.h -= this.attr_('titleHeight');
+ this.area.y += this.attr_('titleHeight');
+ }
+ if (this.attr_('xlabel')) {
+ this.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.
+ }
+
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.
- var ctx = this.element.getContext("2d");
+ var ctx = this.dygraph_.canvas_ctx_;
ctx.beginPath();
ctx.rect(this.area.x, this.area.y, this.area.w, this.area.h);
ctx.clip();
- var ctx = this.dygraph_.hidden_.getContext("2d");
+ ctx = this.dygraph_.hidden_ctx_;
ctx.beginPath();
ctx.rect(this.area.x, this.area.y, this.area.w, this.area.h);
ctx.clip();
};
+DygraphCanvasRenderer.prototype.attr_ = function(x) {
+ return this.dygraph_.attr_(x);
+};
+
DygraphCanvasRenderer.prototype.clear = function() {
if (this.isIE) {
// VML takes a while to start up, so we just poll every this.IEDelay
this.clearDelay.cancel();
this.clearDelay = null;
}
- var context = this.element.getContext("2d");
+ var context = this.elementContext;
}
catch (e) {
// TODO(danvk): this is broken, since MochiKit.Async is gone.
}
}
- var context = this.element.getContext("2d");
+ var context = this.elementContext;
context.clearRect(0, 0, this.width, this.height);
for (var i = 0; i < this.xlabels.length; i++) {
var el = this.xlabels[i];
- el.parentNode.removeChild(el);
+ if (el.parentNode) el.parentNode.removeChild(el);
}
for (var i = 0; i < this.ylabels.length; i++) {
var el = this.ylabels[i];
- el.parentNode.removeChild(el);
+ if (el.parentNode) el.parentNode.removeChild(el);
}
for (var i = 0; i < this.annotations.length; i++) {
var el = this.annotations[i];
- el.parentNode.removeChild(el);
+ if (el.parentNode) el.parentNode.removeChild(el);
+ }
+ 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 = new Array();
this.ylabels = new Array();
this.annotations = new Array();
+ this.chartLabels = {};
};
* Draw an X/Y grid on top of the existing plot
*/
DygraphCanvasRenderer.prototype.render = function() {
- // Draw the new X/Y grid
- var ctx = this.element.getContext("2d");
+ // 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.options.underlayCallback) {
- this.options.underlayCallback(ctx, this.area, this.layout, this.dygraph_);
+ // NOTE: we pass the dygraph object to this callback twice to avoid breaking
+ // users who expect a deprecated form of this callback.
+ this.options.underlayCallback(ctx, this.area, this.dygraph_, this.dygraph_);
}
if (this.options.drawYGrid) {
for (var i = 0; i < ticks.length; i++) {
// TODO(danvk): allow secondary axes to draw a grid, too.
if (ticks[i][0] != 0) continue;
- var x = this.area.x;
- var y = this.area.y + ticks[i][1] * this.area.h;
+ var x = halfUp(this.area.x);
+ var 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.strokeStyle = this.options.gridLineColor;
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;
+ var x = halfUp(this.area.x + ticks[i][0] * this.area.w);
+ var y = halfDown(this.area.y + this.area.h);
ctx.beginPath();
ctx.moveTo(x, y);
ctx.lineTo(x, this.area.y);
// Do the ordinary rendering, as before
this._renderLineChart();
this._renderAxis();
+ this._renderChartLabels();
this._renderAnnotations();
};
if (!this.options.drawXAxis && !this.options.drawYAxis)
return;
- var context = this.element.getContext("2d");
+ // Round pixels to half-integer boundaries for crisper drawing.
+ function halfUp(x){return Math.round(x)+0.5};
+ function halfDown(y){return Math.round(y)-0.5};
+
+ var context = this.elementContext;
var labelStyle = {
"position": "absolute",
}
var y = this.area.y + tick[1] * this.area.h;
context.beginPath();
- context.moveTo(x, y);
- context.lineTo(x - sgn * this.options.axisTickSize, y);
+ context.moveTo(halfUp(x), halfDown(y));
+ context.lineTo(halfUp(x - sgn * this.options.axisTickSize), halfDown(y));
context.closePath();
context.stroke();
label.style.top = top + "px";
}
if (tick[0] == 0) {
- label.style.left = "0px";
+ label.style.left = (this.area.x - this.options.yAxisLabelWidth - this.options.axisTickSize) + "px";
label.style.textAlign = "right";
} else if (tick[0] == 1) {
label.style.left = (this.area.x + this.area.w +
}
}
+ // draw a vertical line on the left to separate the chart from the labels.
context.beginPath();
- context.moveTo(this.area.x, this.area.y);
- context.lineTo(this.area.x, this.area.y + this.area.h);
+ 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(this.area.x + this.area.w, this.area.y);
- context.lineTo(this.area.x + this.area.w, this.area.y + this.area.h);
+ 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();
}
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.moveTo(halfUp(x), halfDown(y));
+ context.lineTo(halfUp(x), halfDown(y + this.options.axisTickSize));
context.closePath();
context.stroke();
var label = makeDiv(tick[1]);
label.style.textAlign = "center";
- label.style.bottom = "0px";
+ label.style.top = (y + this.options.axisTickSize) + 'px';
var left = (x - this.options.axisLabelWidth/2);
if (left + this.options.axisLabelWidth > this.width) {
}
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.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();
}
};
+DygraphCanvasRenderer.prototype._renderChartLabels = function() {
+ // 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')) {
+ var 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';
+ var 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;
+ }
+
+ if (this.attr_('xlabel')) {
+ var 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';
+
+ var 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;
+ }
+
+ if (this.attr_('ylabel')) {
+ var box = {
+ left: 0,
+ top: this.area.y,
+ width: this.attr_('yLabelWidth'),
+ height: this.area.h
+ };
+ // TODO(danvk): is this outer div actually necessary?
+ var div = document.createElement("div");
+ div.style.position = 'absolute';
+ div.style.left = box.left;
+ div.style.top = box.top + 'px';
+ div.style.width = box.width + 'px';
+ div.style.height = box.height + 'px';
+ div.style.fontSize = (this.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.
+ inner_div.style.transform = 'rotate(-90deg)'; // HTML5
+ inner_div.style.WebkitTransform = 'rotate(-90deg)'; // Safari/Chrome
+ inner_div.style.MozTransform = 'rotate(-90deg)'; // Firefox
+ inner_div.style.OTransform = 'rotate(-90deg)'; // Opera
+ inner_div.style.msTransform = 'rotate(-90deg)'; // 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=3)';
+ inner_div.style.left = '0px';
+ inner_div.style.top = '0px';
+ }
+
+ var class_div = document.createElement("div");
+ class_div.className = 'dygraph-label dygraph-ylabel';
+ class_div.innerHTML = this.attr_('ylabel');
+
+ inner_div.appendChild(class_div);
+ div.appendChild(inner_div);
+ this.container.appendChild(div);
+ this.chartLabels.ylabel = div;
+ }
+};
+
+
DygraphCanvasRenderer.prototype._renderAnnotations = function() {
var annotationStyle = {
"position": "absolute",
this.container.appendChild(div);
this.annotations.push(div);
- var ctx = this.element.getContext("2d");
+ var ctx = this.elementContext;
ctx.strokeStyle = this.colors[p.name];
ctx.beginPath();
if (!a.attachAtBottom) {
* Overrides the CanvasRenderer method to draw error bars
*/
DygraphCanvasRenderer.prototype._renderLineChart = function() {
- var context = this.element.getContext("2d");
+ // TODO(danvk): use this.attr_ for many of these.
+ var context = this.elementContext;
var colorCount = this.options.colorScheme.length;
var colorScheme = this.options.colorScheme;
var fillAlpha = this.options.fillAlpha;
var errorBars = this.layout.options.errorBars;
- var fillGraph = this.layout.options.fillGraph;
+ var fillGraph = this.attr_("fillGraph");
var stackedGraph = this.layout.options.stackedGraph;
var stepPlot = this.layout.options.stepPlot;
}
// create paths
- var isOK = function(x) { return x && !isNaN(x); };
-
var ctx = context;
if (errorBars) {
if (fillGraph) {
for (var j = 0; j < this.layout.points.length; j++) {
var point = this.layout.points[j];
if (point.name == setName) {
- if (!isOK(point.y)) {
+ if (!Dygraph.isOK(point.y)) {
prevX = NaN;
continue;
}
for (var j = 0; j < this.layout.points.length; j++) {
var point = this.layout.points[j];
if (point.name == setName) {
- if (!isOK(point.y)) {
+ if (!Dygraph.isOK(point.y)) {
prevX = NaN;
continue;
}
for (var j = 0; j < points.length; j++) {
var point = points[j];
if (point.name == setName) {
- if (!isOK(point.canvasy)) {
+ if (!Dygraph.isOK(point.canvasy)) {
if (stepPlot && prevX != null) {
// Draw a horizontal line to the start of the missing data
ctx.beginPath();
// 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)));
+ !Dygraph.isOK(points[j+1].canvasy)));
if (!prevX) {
prevX = point.canvasx;
projects / dygraphs.git / blobdiff