Merge pull request #63 from kberg/master
[dygraphs.git] / dygraph-canvas.js
1 // Copyright 2006 Dan Vanderkam (danvdk@gmail.com)
2 // All Rights Reserved.
3
4 /**
5 * @fileoverview Based on PlotKit, but modified to meet the needs of dygraphs.
6 * In particular, support for:
7 * - grid overlays
8 * - error bars
9 * - dygraphs attribute system
10 *
11 * High level overview of classes:
12 *
13 * - DygraphLayout
14 * This contains all the data to be charted.
15 * It uses data coordinates, but also records the chart range (in data
16 * coordinates) and hence is able to calculate percentage positions ('In
17 * this view, Point A lies 25% down the x-axis.')
18 * Two things that it does not do are:
19 * 1. Record pixel coordinates for anything.
20 * 2. (oddly) determine anything about the layout of chart elements.
21 * The naming is a vestige of Dygraph's original PlotKit roots.
22 *
23 * - DygraphCanvasRenderer
24 * This class determines the charting area (in pixel coordinates), maps the
25 * percentage coordinates in the DygraphLayout to pixels and draws them.
26 * It's also responsible for creating chart DOM elements, i.e. annotations,
27 * tick mark labels, the title and the x/y-axis labels.
28 */
29
30 /**
31 * Creates a new DygraphLayout object.
32 * @return {Object} The DygraphLayout object
33 */
34 DygraphLayout = function(dygraph) {
35 this.dygraph_ = dygraph;
36 this.datasets = new Array();
37 this.annotations = new Array();
38 this.yAxes_ = null;
39
40 // TODO(danvk): it's odd that xTicks_ and yTicks_ are inputs, but xticks and
41 // yticks are outputs. Clean this up.
42 this.xTicks_ = null;
43 this.yTicks_ = null;
44 };
45
46 DygraphLayout.prototype.attr_ = function(name) {
47 return this.dygraph_.attr_(name);
48 };
49
50 DygraphLayout.prototype.addDataset = function(setname, set_xy) {
51 this.datasets[setname] = set_xy;
52 };
53
54 DygraphLayout.prototype.setAnnotations = function(ann) {
55 // The Dygraph object's annotations aren't parsed. We parse them here and
56 // save a copy. If there is no parser, then the user must be using raw format.
57 this.annotations = [];
58 var parse = this.attr_('xValueParser') || function(x) { return x; };
59 for (var i = 0; i < ann.length; i++) {
60 var a = {};
61 if (!ann[i].xval && !ann[i].x) {
62 this.dygraph_.error("Annotations must have an 'x' property");
63 return;
64 }
65 if (ann[i].icon &&
66 !(ann[i].hasOwnProperty('width') &&
67 ann[i].hasOwnProperty('height'))) {
68 this.dygraph_.error("Must set width and height when setting " +
69 "annotation.icon property");
70 return;
71 }
72 Dygraph.update(a, ann[i]);
73 if (!a.xval) a.xval = parse(a.x);
74 this.annotations.push(a);
75 }
76 };
77
78 DygraphLayout.prototype.setXTicks = function(xTicks) {
79 this.xTicks_ = xTicks;
80 };
81
82 // TODO(danvk): add this to the Dygraph object's API or move it into Layout.
83 DygraphLayout.prototype.setYAxes = function (yAxes) {
84 this.yAxes_ = yAxes;
85 };
86
87 DygraphLayout.prototype.setDateWindow = function(dateWindow) {
88 this.dateWindow_ = dateWindow;
89 };
90
91 DygraphLayout.prototype.evaluate = function() {
92 this._evaluateLimits();
93 this._evaluateLineCharts();
94 this._evaluateLineTicks();
95 this._evaluateAnnotations();
96 };
97
98 DygraphLayout.prototype._evaluateLimits = function() {
99 this.minxval = this.maxxval = null;
100 if (this.dateWindow_) {
101 this.minxval = this.dateWindow_[0];
102 this.maxxval = this.dateWindow_[1];
103 } else {
104 for (var name in this.datasets) {
105 if (!this.datasets.hasOwnProperty(name)) continue;
106 var series = this.datasets[name];
107 if (series.length > 1) {
108 var x1 = series[0][0];
109 if (!this.minxval || x1 < this.minxval) this.minxval = x1;
110
111 var x2 = series[series.length - 1][0];
112 if (!this.maxxval || x2 > this.maxxval) this.maxxval = x2;
113 }
114 }
115 }
116 this.xrange = this.maxxval - this.minxval;
117 this.xscale = (this.xrange != 0 ? 1/this.xrange : 1.0);
118
119 for (var i = 0; i < this.yAxes_.length; i++) {
120 var axis = this.yAxes_[i];
121 axis.minyval = axis.computedValueRange[0];
122 axis.maxyval = axis.computedValueRange[1];
123 axis.yrange = axis.maxyval - axis.minyval;
124 axis.yscale = (axis.yrange != 0 ? 1.0 / axis.yrange : 1.0);
125
126 if (axis.g.attr_("logscale")) {
127 axis.ylogrange = Dygraph.log10(axis.maxyval) - Dygraph.log10(axis.minyval);
128 axis.ylogscale = (axis.ylogrange != 0 ? 1.0 / axis.ylogrange : 1.0);
129 if (!isFinite(axis.ylogrange) || isNaN(axis.ylogrange)) {
130 axis.g.error('axis ' + i + ' of graph at ' + axis.g +
131 ' can\'t be displayed in log scale for range [' +
132 axis.minyval + ' - ' + axis.maxyval + ']');
133 }
134 }
135 }
136 };
137
138 DygraphLayout.prototype._evaluateLineCharts = function() {
139 // add all the rects
140 this.points = new Array();
141 for (var setName in this.datasets) {
142 if (!this.datasets.hasOwnProperty(setName)) continue;
143
144 var dataset = this.datasets[setName];
145 var axis = this.dygraph_.axisPropertiesForSeries(setName);
146
147 for (var j = 0; j < dataset.length; j++) {
148 var item = dataset[j];
149
150 var yval;
151 if (axis.logscale) {
152 yval = 1.0 - ((Dygraph.log10(parseFloat(item[1])) - Dygraph.log10(axis.minyval)) * axis.ylogscale); // really should just be yscale.
153 } else {
154 yval = 1.0 - ((parseFloat(item[1]) - axis.minyval) * axis.yscale);
155 }
156 var point = {
157 // TODO(danvk): here
158 x: ((parseFloat(item[0]) - this.minxval) * this.xscale),
159 y: yval,
160 xval: parseFloat(item[0]),
161 yval: parseFloat(item[1]),
162 name: setName
163 };
164
165 this.points.push(point);
166 }
167 }
168 };
169
170 DygraphLayout.prototype._evaluateLineTicks = function() {
171 this.xticks = new Array();
172 for (var i = 0; i < this.xTicks_.length; i++) {
173 var tick = this.xTicks_[i];
174 var label = tick.label;
175 var pos = this.xscale * (tick.v - this.minxval);
176 if ((pos >= 0.0) && (pos <= 1.0)) {
177 this.xticks.push([pos, label]);
178 }
179 }
180
181 this.yticks = new Array();
182 for (var i = 0; i < this.yAxes_.length; i++ ) {
183 var axis = this.yAxes_[i];
184 for (var j = 0; j < axis.ticks.length; j++) {
185 var tick = axis.ticks[j];
186 var label = tick.label;
187 var pos = this.dygraph_.toPercentYCoord(tick.v, i);
188 if ((pos >= 0.0) && (pos <= 1.0)) {
189 this.yticks.push([i, pos, label]);
190 }
191 }
192 }
193 };
194
195
196 /**
197 * Behaves the same way as PlotKit.Layout, but also copies the errors
198 * @private
199 */
200 DygraphLayout.prototype.evaluateWithError = function() {
201 this.evaluate();
202 if (!(this.attr_('errorBars') || this.attr_('customBars'))) return;
203
204 // Copy over the error terms
205 var i = 0; // index in this.points
206 for (var setName in this.datasets) {
207 if (!this.datasets.hasOwnProperty(setName)) continue;
208 var j = 0;
209 var dataset = this.datasets[setName];
210 for (var j = 0; j < dataset.length; j++, i++) {
211 var item = dataset[j];
212 var xv = parseFloat(item[0]);
213 var yv = parseFloat(item[1]);
214
215 if (xv == this.points[i].xval &&
216 yv == this.points[i].yval) {
217 this.points[i].errorMinus = parseFloat(item[2]);
218 this.points[i].errorPlus = parseFloat(item[3]);
219 }
220 }
221 }
222 };
223
224 DygraphLayout.prototype._evaluateAnnotations = function() {
225 // Add the annotations to the point to which they belong.
226 // Make a map from (setName, xval) to annotation for quick lookups.
227 var annotations = {};
228 for (var i = 0; i < this.annotations.length; i++) {
229 var a = this.annotations[i];
230 annotations[a.xval + "," + a.series] = a;
231 }
232
233 this.annotated_points = [];
234 for (var i = 0; i < this.points.length; i++) {
235 var p = this.points[i];
236 var k = p.xval + "," + p.name;
237 if (k in annotations) {
238 p.annotation = annotations[k];
239 this.annotated_points.push(p);
240 }
241 }
242 };
243
244 /**
245 * Convenience function to remove all the data sets from a graph
246 */
247 DygraphLayout.prototype.removeAllDatasets = function() {
248 delete this.datasets;
249 this.datasets = new Array();
250 };
251
252 /**
253 * Return a copy of the point at the indicated index, with its yval unstacked.
254 * @param int index of point in layout_.points
255 */
256 DygraphLayout.prototype.unstackPointAtIndex = function(idx) {
257 var point = this.points[idx];
258
259 // Clone the point since we modify it
260 var unstackedPoint = {};
261 for (var i in point) {
262 unstackedPoint[i] = point[i];
263 }
264
265 if (!this.attr_("stackedGraph")) {
266 return unstackedPoint;
267 }
268
269 // The unstacked yval is equal to the current yval minus the yval of the
270 // next point at the same xval.
271 for (var i = idx+1; i < this.points.length; i++) {
272 if (this.points[i].xval == point.xval) {
273 unstackedPoint.yval -= this.points[i].yval;
274 break;
275 }
276 }
277
278 return unstackedPoint;
279 }
280
281 /**
282 * The DygraphCanvasRenderer class does the actual rendering of the chart onto
283 * a canvas. It's based on PlotKit.CanvasRenderer.
284 * @param {Object} element The canvas to attach to
285 * @param {Object} elementContext The 2d context of the canvas (injected so it
286 * can be mocked for testing.)
287 * @param {Layout} layout The DygraphLayout object for this graph.
288 */
289 DygraphCanvasRenderer = function(dygraph, element, elementContext, layout) {
290 this.dygraph_ = dygraph;
291
292 this.layout = layout;
293 this.element = element;
294 this.elementContext = elementContext;
295 this.container = this.element.parentNode;
296
297 this.height = this.element.height;
298 this.width = this.element.width;
299
300 // --- check whether everything is ok before we return
301 if (!this.isIE && !(DygraphCanvasRenderer.isSupported(this.element)))
302 throw "Canvas is not supported.";
303
304 // internal state
305 this.xlabels = new Array();
306 this.ylabels = new Array();
307 this.annotations = new Array();
308 this.chartLabels = {};
309
310 this.area = this.computeArea_();
311 this.container.style.position = "relative";
312 this.container.style.width = this.width + "px";
313
314 // Set up a clipping area for the canvas (and the interaction canvas).
315 // This ensures that we don't overdraw.
316 var ctx = this.dygraph_.canvas_ctx_;
317 ctx.beginPath();
318 ctx.rect(this.area.x, this.area.y, this.area.w, this.area.h);
319 ctx.clip();
320
321 ctx = this.dygraph_.hidden_ctx_;
322 ctx.beginPath();
323 ctx.rect(this.area.x, this.area.y, this.area.w, this.area.h);
324 ctx.clip();
325 };
326
327 DygraphCanvasRenderer.prototype.attr_ = function(x) {
328 return this.dygraph_.attr_(x);
329 };
330
331 // Compute the box which the chart should be drawn in. This is the canvas's
332 // box, less space needed for axis and chart labels.
333 // TODO(danvk): this belongs in DygraphLayout.
334 DygraphCanvasRenderer.prototype.computeArea_ = function() {
335 var area = {
336 // TODO(danvk): per-axis setting.
337 x: 0,
338 y: 0
339 };
340 if (this.attr_('drawYAxis')) {
341 area.x = this.attr_('yAxisLabelWidth') + 2 * this.attr_('axisTickSize');
342 }
343
344 area.w = this.width - area.x - this.attr_('rightGap');
345 area.h = this.height;
346 if (this.attr_('drawXAxis')) {
347 area.h -= this.attr_('axisLabelFontSize') + 2 * this.attr_('axisTickSize');
348 }
349
350 // Shrink the drawing area to accomodate additional y-axes.
351 if (this.dygraph_.numAxes() == 2) {
352 // TODO(danvk): per-axis setting.
353 area.w -= (this.attr_('yAxisLabelWidth') + 2 * this.attr_('axisTickSize'));
354 } else if (this.dygraph_.numAxes() > 2) {
355 this.dygraph_.error("Only two y-axes are supported at this time. (Trying " +
356 "to use " + this.dygraph_.numAxes() + ")");
357 }
358
359 // Add space for chart labels: title, xlabel and ylabel.
360 if (this.attr_('title')) {
361 area.h -= this.attr_('titleHeight');
362 area.y += this.attr_('titleHeight');
363 }
364 if (this.attr_('xlabel')) {
365 area.h -= this.attr_('xLabelHeight');
366 }
367 if (this.attr_('ylabel')) {
368 // It would make sense to shift the chart here to make room for the y-axis
369 // label, but the default yAxisLabelWidth is large enough that this results
370 // in overly-padded charts. The y-axis label should fit fine. If it
371 // doesn't, the yAxisLabelWidth option can be increased.
372 }
373
374 return area;
375 };
376
377 DygraphCanvasRenderer.prototype.clear = function() {
378 if (this.isIE) {
379 // VML takes a while to start up, so we just poll every this.IEDelay
380 try {
381 if (this.clearDelay) {
382 this.clearDelay.cancel();
383 this.clearDelay = null;
384 }
385 var context = this.elementContext;
386 }
387 catch (e) {
388 // TODO(danvk): this is broken, since MochiKit.Async is gone.
389 this.clearDelay = MochiKit.Async.wait(this.IEDelay);
390 this.clearDelay.addCallback(bind(this.clear, this));
391 return;
392 }
393 }
394
395 var context = this.elementContext;
396 context.clearRect(0, 0, this.width, this.height);
397
398 for (var i = 0; i < this.xlabels.length; i++) {
399 var el = this.xlabels[i];
400 if (el.parentNode) el.parentNode.removeChild(el);
401 }
402 for (var i = 0; i < this.ylabels.length; i++) {
403 var el = this.ylabels[i];
404 if (el.parentNode) el.parentNode.removeChild(el);
405 }
406 for (var i = 0; i < this.annotations.length; i++) {
407 var el = this.annotations[i];
408 if (el.parentNode) el.parentNode.removeChild(el);
409 }
410 for (var k in this.chartLabels) {
411 if (!this.chartLabels.hasOwnProperty(k)) continue;
412 var el = this.chartLabels[k];
413 if (el.parentNode) el.parentNode.removeChild(el);
414 }
415 this.xlabels = new Array();
416 this.ylabels = new Array();
417 this.annotations = new Array();
418 this.chartLabels = {};
419 };
420
421
422 DygraphCanvasRenderer.isSupported = function(canvasName) {
423 var canvas = null;
424 try {
425 if (typeof(canvasName) == 'undefined' || canvasName == null)
426 canvas = document.createElement("canvas");
427 else
428 canvas = canvasName;
429 var context = canvas.getContext("2d");
430 }
431 catch (e) {
432 var ie = navigator.appVersion.match(/MSIE (\d\.\d)/);
433 var opera = (navigator.userAgent.toLowerCase().indexOf("opera") != -1);
434 if ((!ie) || (ie[1] < 6) || (opera))
435 return false;
436 return true;
437 }
438 return true;
439 };
440
441 /**
442 * @param { [String] } colors Array of color strings. Should have one entry for
443 * each series to be rendered.
444 */
445 DygraphCanvasRenderer.prototype.setColors = function(colors) {
446 this.colorScheme_ = colors;
447 };
448
449 /**
450 * Draw an X/Y grid on top of the existing plot
451 */
452 DygraphCanvasRenderer.prototype.render = function() {
453 // Draw the new X/Y grid. Lines appear crisper when pixels are rounded to
454 // half-integers. This prevents them from drawing in two rows/cols.
455 var ctx = this.elementContext;
456 function halfUp(x){return Math.round(x)+0.5};
457 function halfDown(y){return Math.round(y)-0.5};
458
459 if (this.attr_('underlayCallback')) {
460 // NOTE: we pass the dygraph object to this callback twice to avoid breaking
461 // users who expect a deprecated form of this callback.
462 this.attr_('underlayCallback')(ctx, this.area, this.dygraph_, this.dygraph_);
463 }
464
465 if (this.attr_('drawYGrid')) {
466 var ticks = this.layout.yticks;
467 ctx.save();
468 ctx.strokeStyle = this.attr_('gridLineColor');
469 ctx.lineWidth = this.attr_('gridLineWidth');
470 for (var i = 0; i < ticks.length; i++) {
471 // TODO(danvk): allow secondary axes to draw a grid, too.
472 if (ticks[i][0] != 0) continue;
473 var x = halfUp(this.area.x);
474 var y = halfDown(this.area.y + ticks[i][1] * this.area.h);
475 ctx.beginPath();
476 ctx.moveTo(x, y);
477 ctx.lineTo(x + this.area.w, y);
478 ctx.closePath();
479 ctx.stroke();
480 }
481 }
482
483 if (this.attr_('drawXGrid')) {
484 var ticks = this.layout.xticks;
485 ctx.save();
486 ctx.strokeStyle = this.attr_('gridLineColor');
487 ctx.lineWidth = this.attr_('gridLineWidth');
488 for (var i=0; i<ticks.length; i++) {
489 var x = halfUp(this.area.x + ticks[i][0] * this.area.w);
490 var y = halfDown(this.area.y + this.area.h);
491 ctx.beginPath();
492 ctx.moveTo(x, y);
493 ctx.lineTo(x, this.area.y);
494 ctx.closePath();
495 ctx.stroke();
496 }
497 }
498
499 // Do the ordinary rendering, as before
500 this._renderLineChart();
501 this._renderAxis();
502 this._renderChartLabels();
503 this._renderAnnotations();
504 };
505
506
507 DygraphCanvasRenderer.prototype._renderAxis = function() {
508 if (!this.attr_('drawXAxis') && !this.attr_('drawYAxis')) return;
509
510 // Round pixels to half-integer boundaries for crisper drawing.
511 function halfUp(x){return Math.round(x)+0.5};
512 function halfDown(y){return Math.round(y)-0.5};
513
514 var context = this.elementContext;
515
516 var labelStyle = {
517 position: "absolute",
518 fontSize: this.attr_('axisLabelFontSize') + "px",
519 zIndex: 10,
520 color: this.attr_('axisLabelColor'),
521 width: this.attr_('axisLabelWidth') + "px",
522 overflow: "hidden"
523 };
524 var makeDiv = function(txt) {
525 var div = document.createElement("div");
526 for (var name in labelStyle) {
527 if (labelStyle.hasOwnProperty(name)) {
528 div.style[name] = labelStyle[name];
529 }
530 }
531 div.appendChild(document.createTextNode(txt));
532 return div;
533 };
534
535 // axis lines
536 context.save();
537 context.strokeStyle = this.attr_('axisLineColor');
538 context.lineWidth = this.attr_('axisLineWidth');
539
540 if (this.attr_('drawYAxis')) {
541 if (this.layout.yticks && this.layout.yticks.length > 0) {
542 for (var i = 0; i < this.layout.yticks.length; i++) {
543 var tick = this.layout.yticks[i];
544 if (typeof(tick) == "function") return;
545 var x = this.area.x;
546 var sgn = 1;
547 if (tick[0] == 1) { // right-side y-axis
548 x = this.area.x + this.area.w;
549 sgn = -1;
550 }
551 var y = this.area.y + tick[1] * this.area.h;
552 context.beginPath();
553 context.moveTo(halfUp(x), halfDown(y));
554 context.lineTo(halfUp(x - sgn * this.attr_('axisTickSize')), halfDown(y));
555 context.closePath();
556 context.stroke();
557
558 var label = makeDiv(tick[2]);
559 var top = (y - this.attr_('axisLabelFontSize') / 2);
560 if (top < 0) top = 0;
561
562 if (top + this.attr_('axisLabelFontSize') + 3 > this.height) {
563 label.style.bottom = "0px";
564 } else {
565 label.style.top = top + "px";
566 }
567 if (tick[0] == 0) {
568 label.style.left = (this.area.x - this.attr_('yAxisLabelWidth') - this.attr_('axisTickSize')) + "px";
569 label.style.textAlign = "right";
570 } else if (tick[0] == 1) {
571 label.style.left = (this.area.x + this.area.w +
572 this.attr_('axisTickSize')) + "px";
573 label.style.textAlign = "left";
574 }
575 label.style.width = this.attr_('yAxisLabelWidth') + "px";
576 this.container.appendChild(label);
577 this.ylabels.push(label);
578 }
579
580 // The lowest tick on the y-axis often overlaps with the leftmost
581 // tick on the x-axis. Shift the bottom tick up a little bit to
582 // compensate if necessary.
583 var bottomTick = this.ylabels[0];
584 var fontSize = this.attr_('axisLabelFontSize');
585 var bottom = parseInt(bottomTick.style.top) + fontSize;
586 if (bottom > this.height - fontSize) {
587 bottomTick.style.top = (parseInt(bottomTick.style.top) -
588 fontSize / 2) + "px";
589 }
590 }
591
592 // draw a vertical line on the left to separate the chart from the labels.
593 context.beginPath();
594 context.moveTo(halfUp(this.area.x), halfDown(this.area.y));
595 context.lineTo(halfUp(this.area.x), halfDown(this.area.y + this.area.h));
596 context.closePath();
597 context.stroke();
598
599 // if there's a secondary y-axis, draw a vertical line for that, too.
600 if (this.dygraph_.numAxes() == 2) {
601 context.beginPath();
602 context.moveTo(halfDown(this.area.x + this.area.w), halfDown(this.area.y));
603 context.lineTo(halfDown(this.area.x + this.area.w), halfDown(this.area.y + this.area.h));
604 context.closePath();
605 context.stroke();
606 }
607 }
608
609 if (this.attr_('drawXAxis')) {
610 if (this.layout.xticks) {
611 for (var i = 0; i < this.layout.xticks.length; i++) {
612 var tick = this.layout.xticks[i];
613 if (typeof(dataset) == "function") return;
614
615 var x = this.area.x + tick[0] * this.area.w;
616 var y = this.area.y + this.area.h;
617 context.beginPath();
618 context.moveTo(halfUp(x), halfDown(y));
619 context.lineTo(halfUp(x), halfDown(y + this.attr_('axisTickSize')));
620 context.closePath();
621 context.stroke();
622
623 var label = makeDiv(tick[1]);
624 label.style.textAlign = "center";
625 label.style.top = (y + this.attr_('axisTickSize')) + 'px';
626
627 var left = (x - this.attr_('axisLabelWidth')/2);
628 if (left + this.attr_('axisLabelWidth') > this.width) {
629 left = this.width - this.attr_('xAxisLabelWidth');
630 label.style.textAlign = "right";
631 }
632 if (left < 0) {
633 left = 0;
634 label.style.textAlign = "left";
635 }
636
637 label.style.left = left + "px";
638 label.style.width = this.attr_('xAxisLabelWidth') + "px";
639 this.container.appendChild(label);
640 this.xlabels.push(label);
641 }
642 }
643
644 context.beginPath();
645 context.moveTo(halfUp(this.area.x), halfDown(this.area.y + this.area.h));
646 context.lineTo(halfUp(this.area.x + this.area.w), halfDown(this.area.y + this.area.h));
647 context.closePath();
648 context.stroke();
649 }
650
651 context.restore();
652 };
653
654
655 DygraphCanvasRenderer.prototype._renderChartLabels = function() {
656 // Generate divs for the chart title, xlabel and ylabel.
657 // Space for these divs has already been taken away from the charting area in
658 // the DygraphCanvasRenderer constructor.
659 if (this.attr_('title')) {
660 var div = document.createElement("div");
661 div.style.position = 'absolute';
662 div.style.top = '0px';
663 div.style.left = this.area.x + 'px';
664 div.style.width = this.area.w + 'px';
665 div.style.height = this.attr_('titleHeight') + 'px';
666 div.style.textAlign = 'center';
667 div.style.fontSize = (this.attr_('titleHeight') - 8) + 'px';
668 div.style.fontWeight = 'bold';
669 var class_div = document.createElement("div");
670 class_div.className = 'dygraph-label dygraph-title';
671 class_div.innerHTML = this.attr_('title');
672 div.appendChild(class_div);
673 this.container.appendChild(div);
674 this.chartLabels.title = div;
675 }
676
677 if (this.attr_('xlabel')) {
678 var div = document.createElement("div");
679 div.style.position = 'absolute';
680 div.style.bottom = 0; // TODO(danvk): this is lazy. Calculate style.top.
681 div.style.left = this.area.x + 'px';
682 div.style.width = this.area.w + 'px';
683 div.style.height = this.attr_('xLabelHeight') + 'px';
684 div.style.textAlign = 'center';
685 div.style.fontSize = (this.attr_('xLabelHeight') - 2) + 'px';
686
687 var class_div = document.createElement("div");
688 class_div.className = 'dygraph-label dygraph-xlabel';
689 class_div.innerHTML = this.attr_('xlabel');
690 div.appendChild(class_div);
691 this.container.appendChild(div);
692 this.chartLabels.xlabel = div;
693 }
694
695 if (this.attr_('ylabel')) {
696 var box = {
697 left: 0,
698 top: this.area.y,
699 width: this.attr_('yLabelWidth'),
700 height: this.area.h
701 };
702 // TODO(danvk): is this outer div actually necessary?
703 var div = document.createElement("div");
704 div.style.position = 'absolute';
705 div.style.left = box.left;
706 div.style.top = box.top + 'px';
707 div.style.width = box.width + 'px';
708 div.style.height = box.height + 'px';
709 div.style.fontSize = (this.attr_('yLabelWidth') - 2) + 'px';
710
711 var inner_div = document.createElement("div");
712 inner_div.style.position = 'absolute';
713 inner_div.style.width = box.height + 'px';
714 inner_div.style.height = box.width + 'px';
715 inner_div.style.top = (box.height / 2 - box.width / 2) + 'px';
716 inner_div.style.left = (box.width / 2 - box.height / 2) + 'px';
717 inner_div.style.textAlign = 'center';
718
719 // CSS rotation is an HTML5 feature which is not standardized. Hence every
720 // browser has its own name for the CSS style.
721 inner_div.style.transform = 'rotate(-90deg)'; // HTML5
722 inner_div.style.WebkitTransform = 'rotate(-90deg)'; // Safari/Chrome
723 inner_div.style.MozTransform = 'rotate(-90deg)'; // Firefox
724 inner_div.style.OTransform = 'rotate(-90deg)'; // Opera
725 inner_div.style.msTransform = 'rotate(-90deg)'; // IE9
726
727 if (typeof(document.documentMode) !== 'undefined' &&
728 document.documentMode < 9) {
729 // We're dealing w/ an old version of IE, so we have to rotate the text
730 // using a BasicImage transform. This uses a different origin of rotation
731 // than HTML5 rotation (top left of div vs. its center).
732 inner_div.style.filter =
733 'progid:DXImageTransform.Microsoft.BasicImage(rotation=3)';
734 inner_div.style.left = '0px';
735 inner_div.style.top = '0px';
736 }
737
738 var class_div = document.createElement("div");
739 class_div.className = 'dygraph-label dygraph-ylabel';
740 class_div.innerHTML = this.attr_('ylabel');
741
742 inner_div.appendChild(class_div);
743 div.appendChild(inner_div);
744 this.container.appendChild(div);
745 this.chartLabels.ylabel = div;
746 }
747 };
748
749
750 DygraphCanvasRenderer.prototype._renderAnnotations = function() {
751 var annotationStyle = {
752 "position": "absolute",
753 "fontSize": this.attr_('axisLabelFontSize') + "px",
754 "zIndex": 10,
755 "overflow": "hidden"
756 };
757
758 var bindEvt = function(eventName, classEventName, p, self) {
759 return function(e) {
760 var a = p.annotation;
761 if (a.hasOwnProperty(eventName)) {
762 a[eventName](a, p, self.dygraph_, e);
763 } else if (self.dygraph_.attr_(classEventName)) {
764 self.dygraph_.attr_(classEventName)(a, p, self.dygraph_,e );
765 }
766 };
767 }
768
769 // Get a list of point with annotations.
770 var points = this.layout.annotated_points;
771 for (var i = 0; i < points.length; i++) {
772 var p = points[i];
773 if (p.canvasx < this.area.x || p.canvasx > this.area.x + this.area.w) {
774 continue;
775 }
776
777 var a = p.annotation;
778 var tick_height = 6;
779 if (a.hasOwnProperty("tickHeight")) {
780 tick_height = a.tickHeight;
781 }
782
783 var div = document.createElement("div");
784 for (var name in annotationStyle) {
785 if (annotationStyle.hasOwnProperty(name)) {
786 div.style[name] = annotationStyle[name];
787 }
788 }
789 if (!a.hasOwnProperty('icon')) {
790 div.className = "dygraphDefaultAnnotation";
791 }
792 if (a.hasOwnProperty('cssClass')) {
793 div.className += " " + a.cssClass;
794 }
795
796 var width = a.hasOwnProperty('width') ? a.width : 16;
797 var height = a.hasOwnProperty('height') ? a.height : 16;
798 if (a.hasOwnProperty('icon')) {
799 var img = document.createElement("img");
800 img.src = a.icon;
801 img.width = width;
802 img.height = height;
803 div.appendChild(img);
804 } else if (p.annotation.hasOwnProperty('shortText')) {
805 div.appendChild(document.createTextNode(p.annotation.shortText));
806 }
807 div.style.left = (p.canvasx - width / 2) + "px";
808 if (a.attachAtBottom) {
809 div.style.top = (this.area.h - height - tick_height) + "px";
810 } else {
811 div.style.top = (p.canvasy - height - tick_height) + "px";
812 }
813 div.style.width = width + "px";
814 div.style.height = height + "px";
815 div.title = p.annotation.text;
816 div.style.color = this.colors[p.name];
817 div.style.borderColor = this.colors[p.name];
818 a.div = div;
819
820 Dygraph.addEvent(div, 'click',
821 bindEvt('clickHandler', 'annotationClickHandler', p, this));
822 Dygraph.addEvent(div, 'mouseover',
823 bindEvt('mouseOverHandler', 'annotationMouseOverHandler', p, this));
824 Dygraph.addEvent(div, 'mouseout',
825 bindEvt('mouseOutHandler', 'annotationMouseOutHandler', p, this));
826 Dygraph.addEvent(div, 'dblclick',
827 bindEvt('dblClickHandler', 'annotationDblClickHandler', p, this));
828
829 this.container.appendChild(div);
830 this.annotations.push(div);
831
832 var ctx = this.elementContext;
833 ctx.strokeStyle = this.colors[p.name];
834 ctx.beginPath();
835 if (!a.attachAtBottom) {
836 ctx.moveTo(p.canvasx, p.canvasy);
837 ctx.lineTo(p.canvasx, p.canvasy - 2 - tick_height);
838 } else {
839 ctx.moveTo(p.canvasx, this.area.h);
840 ctx.lineTo(p.canvasx, this.area.h - 2 - tick_height);
841 }
842 ctx.closePath();
843 ctx.stroke();
844 }
845 };
846
847
848 /**
849 * Overrides the CanvasRenderer method to draw error bars
850 */
851 DygraphCanvasRenderer.prototype._renderLineChart = function() {
852 // TODO(danvk): use this.attr_ for many of these.
853 var context = this.elementContext;
854 var fillAlpha = this.attr_('fillAlpha');
855 var errorBars = this.attr_("errorBars") || this.attr_("customBars");
856 var fillGraph = this.attr_("fillGraph");
857 var stackedGraph = this.attr_("stackedGraph");
858 var stepPlot = this.attr_("stepPlot");
859
860 var setNames = [];
861 for (var name in this.layout.datasets) {
862 if (this.layout.datasets.hasOwnProperty(name)) {
863 setNames.push(name);
864 }
865 }
866 var setCount = setNames.length;
867
868 // TODO(danvk): Move this mapping into Dygraph and get it out of here.
869 this.colors = {}
870 for (var i = 0; i < setCount; i++) {
871 this.colors[setNames[i]] = this.colorScheme_[i % this.colorScheme_.length];
872 }
873
874 // Update Points
875 // TODO(danvk): here
876 for (var i = 0; i < this.layout.points.length; i++) {
877 var point = this.layout.points[i];
878 point.canvasx = this.area.w * point.x + this.area.x;
879 point.canvasy = this.area.h * point.y + this.area.y;
880 }
881
882 // create paths
883 var ctx = context;
884 if (errorBars) {
885 if (fillGraph) {
886 this.dygraph_.warn("Can't use fillGraph option with error bars");
887 }
888
889 for (var i = 0; i < setCount; i++) {
890 var setName = setNames[i];
891 var axis = this.dygraph_.axisPropertiesForSeries(setName);
892 var color = this.colors[setName];
893
894 // setup graphics context
895 ctx.save();
896 var prevX = NaN;
897 var prevY = NaN;
898 var prevYs = [-1, -1];
899 var yscale = axis.yscale;
900 // should be same color as the lines but only 15% opaque.
901 var rgb = new RGBColor(color);
902 var err_color = 'rgba(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ',' +
903 fillAlpha + ')';
904 ctx.fillStyle = err_color;
905 ctx.beginPath();
906 for (var j = 0; j < this.layout.points.length; j++) {
907 var point = this.layout.points[j];
908 if (point.name == setName) {
909 if (!Dygraph.isOK(point.y)) {
910 prevX = NaN;
911 continue;
912 }
913
914 // TODO(danvk): here
915 if (stepPlot) {
916 var newYs = [ prevY - point.errorPlus * yscale,
917 prevY + point.errorMinus * yscale ];
918 prevY = point.y;
919 } else {
920 var newYs = [ point.y - point.errorPlus * yscale,
921 point.y + point.errorMinus * yscale ];
922 }
923 newYs[0] = this.area.h * newYs[0] + this.area.y;
924 newYs[1] = this.area.h * newYs[1] + this.area.y;
925 if (!isNaN(prevX)) {
926 if (stepPlot) {
927 ctx.moveTo(prevX, newYs[0]);
928 } else {
929 ctx.moveTo(prevX, prevYs[0]);
930 }
931 ctx.lineTo(point.canvasx, newYs[0]);
932 ctx.lineTo(point.canvasx, newYs[1]);
933 if (stepPlot) {
934 ctx.lineTo(prevX, newYs[1]);
935 } else {
936 ctx.lineTo(prevX, prevYs[1]);
937 }
938 ctx.closePath();
939 }
940 prevYs = newYs;
941 prevX = point.canvasx;
942 }
943 }
944 ctx.fill();
945 }
946 } else if (fillGraph) {
947 var baseline = [] // for stacked graphs: baseline for filling
948
949 // process sets in reverse order (needed for stacked graphs)
950 for (var i = setCount - 1; i >= 0; i--) {
951 var setName = setNames[i];
952 var color = this.colors[setName];
953 var axis = this.dygraph_.axisPropertiesForSeries(setName);
954 var axisY = 1.0 + axis.minyval * axis.yscale;
955 if (axisY < 0.0) axisY = 0.0;
956 else if (axisY > 1.0) axisY = 1.0;
957 axisY = this.area.h * axisY + this.area.y;
958
959 // setup graphics context
960 ctx.save();
961 var prevX = NaN;
962 var prevYs = [-1, -1];
963 var yscale = axis.yscale;
964 // should be same color as the lines but only 15% opaque.
965 var rgb = new RGBColor(color);
966 var err_color = 'rgba(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ',' +
967 fillAlpha + ')';
968 ctx.fillStyle = err_color;
969 ctx.beginPath();
970 for (var j = 0; j < this.layout.points.length; j++) {
971 var point = this.layout.points[j];
972 if (point.name == setName) {
973 if (!Dygraph.isOK(point.y)) {
974 prevX = NaN;
975 continue;
976 }
977 var newYs;
978 if (stackedGraph) {
979 lastY = baseline[point.canvasx];
980 if (lastY === undefined) lastY = axisY;
981 baseline[point.canvasx] = point.canvasy;
982 newYs = [ point.canvasy, lastY ];
983 } else {
984 newYs = [ point.canvasy, axisY ];
985 }
986 if (!isNaN(prevX)) {
987 ctx.moveTo(prevX, prevYs[0]);
988 if (stepPlot) {
989 ctx.lineTo(point.canvasx, prevYs[0]);
990 } else {
991 ctx.lineTo(point.canvasx, newYs[0]);
992 }
993 ctx.lineTo(point.canvasx, newYs[1]);
994 ctx.lineTo(prevX, prevYs[1]);
995 ctx.closePath();
996 }
997 prevYs = newYs;
998 prevX = point.canvasx;
999 }
1000 }
1001 ctx.fill();
1002 }
1003 }
1004
1005 for (var i = 0; i < setCount; i++) {
1006 var setName = setNames[i];
1007 var color = this.colors[setName];
1008 var strokeWidth = this.dygraph_.attr_("strokeWidth", setName);
1009
1010 // setup graphics context
1011 context.save();
1012 var point = this.layout.points[0];
1013 var pointSize = this.dygraph_.attr_("pointSize", setName);
1014 var prevX = null, prevY = null;
1015 var drawPoints = this.dygraph_.attr_("drawPoints", setName);
1016 var points = this.layout.points;
1017 for (var j = 0; j < points.length; j++) {
1018 var point = points[j];
1019 if (point.name == setName) {
1020 if (!Dygraph.isOK(point.canvasy)) {
1021 if (stepPlot && prevX != null) {
1022 // Draw a horizontal line to the start of the missing data
1023 ctx.beginPath();
1024 ctx.strokeStyle = color;
1025 ctx.lineWidth = this.attr_('strokeWidth');
1026 ctx.moveTo(prevX, prevY);
1027 ctx.lineTo(point.canvasx, prevY);
1028 ctx.stroke();
1029 }
1030 // this will make us move to the next point, not draw a line to it.
1031 prevX = prevY = null;
1032 } else {
1033 // A point is "isolated" if it is non-null but both the previous
1034 // and next points are null.
1035 var isIsolated = (!prevX && (j == points.length - 1 ||
1036 !Dygraph.isOK(points[j+1].canvasy)));
1037
1038 if (!prevX) {
1039 prevX = point.canvasx;
1040 prevY = point.canvasy;
1041 } else {
1042 // TODO(danvk): figure out why this conditional is necessary.
1043 if (strokeWidth) {
1044 ctx.beginPath();
1045 ctx.strokeStyle = color;
1046 ctx.lineWidth = strokeWidth;
1047 ctx.moveTo(prevX, prevY);
1048 if (stepPlot) {
1049 ctx.lineTo(point.canvasx, prevY);
1050 }
1051 prevX = point.canvasx;
1052 prevY = point.canvasy;
1053 ctx.lineTo(prevX, prevY);
1054 ctx.stroke();
1055 }
1056 }
1057
1058 if (drawPoints || isIsolated) {
1059 ctx.beginPath();
1060 ctx.fillStyle = color;
1061 ctx.arc(point.canvasx, point.canvasy, pointSize,
1062 0, 2 * Math.PI, false);
1063 ctx.fill();
1064 }
1065 }
1066 }
1067 }
1068 }
1069
1070 context.restore();
1071 };