| 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"); |
| 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 | }; |