| 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 | * @param {Object} options Options for PlotKit.Layout |
| 33 | * @return {Object} The DygraphLayout object |
| 34 | */ |
| 35 | DygraphLayout = function(dygraph, options) { |
| 36 | this.dygraph_ = dygraph; |
| 37 | this.options = {}; // TODO(danvk): remove, use attr_ instead. |
| 38 | Dygraph.update(this.options, options ? options : {}); |
| 39 | this.datasets = new Array(); |
| 40 | this.annotations = new Array(); |
| 41 | }; |
| 42 | |
| 43 | DygraphLayout.prototype.attr_ = function(name) { |
| 44 | return this.dygraph_.attr_(name); |
| 45 | }; |
| 46 | |
| 47 | DygraphLayout.prototype.addDataset = function(setname, set_xy) { |
| 48 | this.datasets[setname] = set_xy; |
| 49 | }; |
| 50 | |
| 51 | DygraphLayout.prototype.setAnnotations = function(ann) { |
| 52 | // The Dygraph object's annotations aren't parsed. We parse them here and |
| 53 | // save a copy. If there is no parser, then the user must be using raw format. |
| 54 | this.annotations = []; |
| 55 | var parse = this.attr_('xValueParser') || function(x) { return x; }; |
| 56 | for (var i = 0; i < ann.length; i++) { |
| 57 | var a = {}; |
| 58 | if (!ann[i].xval && !ann[i].x) { |
| 59 | this.dygraph_.error("Annotations must have an 'x' property"); |
| 60 | return; |
| 61 | } |
| 62 | if (ann[i].icon && |
| 63 | !(ann[i].hasOwnProperty('width') && |
| 64 | ann[i].hasOwnProperty('height'))) { |
| 65 | this.dygraph_.error("Must set width and height when setting " + |
| 66 | "annotation.icon property"); |
| 67 | return; |
| 68 | } |
| 69 | Dygraph.update(a, ann[i]); |
| 70 | if (!a.xval) a.xval = parse(a.x); |
| 71 | this.annotations.push(a); |
| 72 | } |
| 73 | }; |
| 74 | |
| 75 | DygraphLayout.prototype.evaluate = function() { |
| 76 | this._evaluateLimits(); |
| 77 | this._evaluateLineCharts(); |
| 78 | this._evaluateLineTicks(); |
| 79 | this._evaluateAnnotations(); |
| 80 | }; |
| 81 | |
| 82 | DygraphLayout.prototype._evaluateLimits = function() { |
| 83 | this.minxval = this.maxxval = null; |
| 84 | if (this.options.dateWindow) { |
| 85 | this.minxval = this.options.dateWindow[0]; |
| 86 | this.maxxval = this.options.dateWindow[1]; |
| 87 | } else { |
| 88 | for (var name in this.datasets) { |
| 89 | if (!this.datasets.hasOwnProperty(name)) continue; |
| 90 | var series = this.datasets[name]; |
| 91 | if (series.length > 1) { |
| 92 | var x1 = series[0][0]; |
| 93 | if (!this.minxval || x1 < this.minxval) this.minxval = x1; |
| 94 | |
| 95 | var x2 = series[series.length - 1][0]; |
| 96 | if (!this.maxxval || x2 > this.maxxval) this.maxxval = x2; |
| 97 | } |
| 98 | } |
| 99 | } |
| 100 | this.xrange = this.maxxval - this.minxval; |
| 101 | this.xscale = (this.xrange != 0 ? 1/this.xrange : 1.0); |
| 102 | |
| 103 | for (var i = 0; i < this.options.yAxes.length; i++) { |
| 104 | var axis = this.options.yAxes[i]; |
| 105 | axis.minyval = axis.computedValueRange[0]; |
| 106 | axis.maxyval = axis.computedValueRange[1]; |
| 107 | axis.yrange = axis.maxyval - axis.minyval; |
| 108 | axis.yscale = (axis.yrange != 0 ? 1.0 / axis.yrange : 1.0); |
| 109 | |
| 110 | if (axis.g.attr_("logscale")) { |
| 111 | axis.ylogrange = Dygraph.log10(axis.maxyval) - Dygraph.log10(axis.minyval); |
| 112 | axis.ylogscale = (axis.ylogrange != 0 ? 1.0 / axis.ylogrange : 1.0); |
| 113 | if (!isFinite(axis.ylogrange) || isNaN(axis.ylogrange)) { |
| 114 | axis.g.error('axis ' + i + ' of graph at ' + axis.g + |
| 115 | ' can\'t be displayed in log scale for range [' + |
| 116 | axis.minyval + ' - ' + axis.maxyval + ']'); |
| 117 | } |
| 118 | } |
| 119 | } |
| 120 | }; |
| 121 | |
| 122 | DygraphLayout.prototype._evaluateLineCharts = function() { |
| 123 | // add all the rects |
| 124 | this.points = new Array(); |
| 125 | for (var setName in this.datasets) { |
| 126 | if (!this.datasets.hasOwnProperty(setName)) continue; |
| 127 | |
| 128 | var dataset = this.datasets[setName]; |
| 129 | var axis = this.options.yAxes[this.options.seriesToAxisMap[setName]]; |
| 130 | |
| 131 | for (var j = 0; j < dataset.length; j++) { |
| 132 | var item = dataset[j]; |
| 133 | |
| 134 | var yval; |
| 135 | if (axis.logscale) { |
| 136 | yval = 1.0 - ((Dygraph.log10(parseFloat(item[1])) - Dygraph.log10(axis.minyval)) * axis.ylogscale); // really should just be yscale. |
| 137 | } else { |
| 138 | yval = 1.0 - ((parseFloat(item[1]) - axis.minyval) * axis.yscale); |
| 139 | } |
| 140 | var point = { |
| 141 | // TODO(danvk): here |
| 142 | x: ((parseFloat(item[0]) - this.minxval) * this.xscale), |
| 143 | y: yval, |
| 144 | xval: parseFloat(item[0]), |
| 145 | yval: parseFloat(item[1]), |
| 146 | name: setName |
| 147 | }; |
| 148 | |
| 149 | this.points.push(point); |
| 150 | } |
| 151 | } |
| 152 | }; |
| 153 | |
| 154 | DygraphLayout.prototype._evaluateLineTicks = function() { |
| 155 | this.xticks = new Array(); |
| 156 | for (var i = 0; i < this.options.xTicks.length; i++) { |
| 157 | var tick = this.options.xTicks[i]; |
| 158 | var label = tick.label; |
| 159 | var pos = this.xscale * (tick.v - this.minxval); |
| 160 | if ((pos >= 0.0) && (pos <= 1.0)) { |
| 161 | this.xticks.push([pos, label]); |
| 162 | } |
| 163 | } |
| 164 | |
| 165 | this.yticks = new Array(); |
| 166 | for (var i = 0; i < this.options.yAxes.length; i++ ) { |
| 167 | var axis = this.options.yAxes[i]; |
| 168 | for (var j = 0; j < axis.ticks.length; j++) { |
| 169 | var tick = axis.ticks[j]; |
| 170 | var label = tick.label; |
| 171 | var pos = this.dygraph_.toPercentYCoord(tick.v, i); |
| 172 | if ((pos >= 0.0) && (pos <= 1.0)) { |
| 173 | this.yticks.push([i, pos, label]); |
| 174 | } |
| 175 | } |
| 176 | } |
| 177 | }; |
| 178 | |
| 179 | |
| 180 | /** |
| 181 | * Behaves the same way as PlotKit.Layout, but also copies the errors |
| 182 | * @private |
| 183 | */ |
| 184 | DygraphLayout.prototype.evaluateWithError = function() { |
| 185 | this.evaluate(); |
| 186 | if (!this.options.errorBars) return; |
| 187 | |
| 188 | // Copy over the error terms |
| 189 | var i = 0; // index in this.points |
| 190 | for (var setName in this.datasets) { |
| 191 | if (!this.datasets.hasOwnProperty(setName)) continue; |
| 192 | var j = 0; |
| 193 | var dataset = this.datasets[setName]; |
| 194 | for (var j = 0; j < dataset.length; j++, i++) { |
| 195 | var item = dataset[j]; |
| 196 | var xv = parseFloat(item[0]); |
| 197 | var yv = parseFloat(item[1]); |
| 198 | |
| 199 | if (xv == this.points[i].xval && |
| 200 | yv == this.points[i].yval) { |
| 201 | this.points[i].errorMinus = parseFloat(item[2]); |
| 202 | this.points[i].errorPlus = parseFloat(item[3]); |
| 203 | } |
| 204 | } |
| 205 | } |
| 206 | }; |
| 207 | |
| 208 | DygraphLayout.prototype._evaluateAnnotations = function() { |
| 209 | // Add the annotations to the point to which they belong. |
| 210 | // Make a map from (setName, xval) to annotation for quick lookups. |
| 211 | var annotations = {}; |
| 212 | for (var i = 0; i < this.annotations.length; i++) { |
| 213 | var a = this.annotations[i]; |
| 214 | annotations[a.xval + "," + a.series] = a; |
| 215 | } |
| 216 | |
| 217 | this.annotated_points = []; |
| 218 | for (var i = 0; i < this.points.length; i++) { |
| 219 | var p = this.points[i]; |
| 220 | var k = p.xval + "," + p.name; |
| 221 | if (k in annotations) { |
| 222 | p.annotation = annotations[k]; |
| 223 | this.annotated_points.push(p); |
| 224 | } |
| 225 | } |
| 226 | }; |
| 227 | |
| 228 | /** |
| 229 | * Convenience function to remove all the data sets from a graph |
| 230 | */ |
| 231 | DygraphLayout.prototype.removeAllDatasets = function() { |
| 232 | delete this.datasets; |
| 233 | this.datasets = new Array(); |
| 234 | }; |
| 235 | |
| 236 | /** |
| 237 | * Change the values of various layout options |
| 238 | * @param {Object} new_options an associative array of new properties |
| 239 | */ |
| 240 | DygraphLayout.prototype.updateOptions = function(new_options) { |
| 241 | Dygraph.update(this.options, new_options ? new_options : {}); |
| 242 | }; |
| 243 | |
| 244 | /** |
| 245 | * Return a copy of the point at the indicated index, with its yval unstacked. |
| 246 | * @param int index of point in layout_.points |
| 247 | */ |
| 248 | DygraphLayout.prototype.unstackPointAtIndex = function(idx) { |
| 249 | var point = this.points[idx]; |
| 250 | |
| 251 | // Clone the point since we modify it |
| 252 | var unstackedPoint = {}; |
| 253 | for (var i in point) { |
| 254 | unstackedPoint[i] = point[i]; |
| 255 | } |
| 256 | |
| 257 | if (!this.attr_("stackedGraph")) { |
| 258 | return unstackedPoint; |
| 259 | } |
| 260 | |
| 261 | // The unstacked yval is equal to the current yval minus the yval of the |
| 262 | // next point at the same xval. |
| 263 | for (var i = idx+1; i < this.points.length; i++) { |
| 264 | if (this.points[i].xval == point.xval) { |
| 265 | unstackedPoint.yval -= this.points[i].yval; |
| 266 | break; |
| 267 | } |
| 268 | } |
| 269 | |
| 270 | return unstackedPoint; |
| 271 | } |
| 272 | |
| 273 | // Subclass PlotKit.CanvasRenderer to add: |
| 274 | // 1. X/Y grid overlay |
| 275 | // 2. Ability to draw error bars (if required) |
| 276 | |
| 277 | /** |
| 278 | * Sets some PlotKit.CanvasRenderer options |
| 279 | * @param {Object} element The canvas to attach to |
| 280 | * @param {Object} elementContext The 2d context of the canvas (injected so it |
| 281 | * can be mocked for testing.) |
| 282 | * @param {Layout} layout The DygraphLayout object for this graph. |
| 283 | * @param {Object} options Options to pass on to CanvasRenderer |
| 284 | */ |
| 285 | DygraphCanvasRenderer = function(dygraph, element, elementContext, layout, |
| 286 | options) { |
| 287 | // TODO(danvk): remove options, just use dygraph.attr_. |
| 288 | this.dygraph_ = dygraph; |
| 289 | |
| 290 | // default options |
| 291 | this.options = { |
| 292 | "strokeWidth": 0.5, |
| 293 | "drawXAxis": true, |
| 294 | "drawYAxis": true, |
| 295 | "axisLineColor": "black", |
| 296 | "axisLineWidth": 0.5, |
| 297 | "axisTickSize": 3, |
| 298 | "axisLabelColor": "black", |
| 299 | "axisLabelFont": "Arial", |
| 300 | "axisLabelFontSize": 9, |
| 301 | "axisLabelWidth": 50, |
| 302 | "drawYGrid": true, |
| 303 | "drawXGrid": true, |
| 304 | "gridLineColor": "rgb(128,128,128)", |
| 305 | "fillAlpha": 0.15, |
| 306 | "underlayCallback": null |
| 307 | }; |
| 308 | Dygraph.update(this.options, options); |
| 309 | |
| 310 | this.layout = layout; |
| 311 | this.element = element; |
| 312 | this.elementContext = elementContext; |
| 313 | this.container = this.element.parentNode; |
| 314 | |
| 315 | this.height = this.element.height; |
| 316 | this.width = this.element.width; |
| 317 | |
| 318 | // --- check whether everything is ok before we return |
| 319 | if (!this.isIE && !(DygraphCanvasRenderer.isSupported(this.element))) |
| 320 | throw "Canvas is not supported."; |
| 321 | |
| 322 | // internal state |
| 323 | this.xlabels = new Array(); |
| 324 | this.ylabels = new Array(); |
| 325 | this.annotations = new Array(); |
| 326 | this.chartLabels = {}; |
| 327 | |
| 328 | // TODO(danvk): consider all axes in this computation. |
| 329 | this.area = { |
| 330 | // TODO(danvk): per-axis setting. |
| 331 | x: this.options.yAxisLabelWidth + 2 * this.options.axisTickSize, |
| 332 | y: 0 |
| 333 | }; |
| 334 | this.area.w = this.width - this.area.x - this.options.rightGap; |
| 335 | this.area.h = this.height - this.options.axisLabelFontSize - |
| 336 | 2 * this.options.axisTickSize; |
| 337 | |
| 338 | // Shrink the drawing area to accomodate additional y-axes. |
| 339 | if (this.dygraph_.numAxes() == 2) { |
| 340 | // TODO(danvk): per-axis setting. |
| 341 | this.area.w -= (this.options.yAxisLabelWidth + 2 * this.options.axisTickSize); |
| 342 | } else if (this.dygraph_.numAxes() > 2) { |
| 343 | this.dygraph_.error("Only two y-axes are supported at this time. (Trying " + |
| 344 | "to use " + this.dygraph_.numAxes() + ")"); |
| 345 | } |
| 346 | |
| 347 | // Add space for chart labels: title, xlabel and ylabel. |
| 348 | if (this.attr_('title')) { |
| 349 | this.area.h -= this.attr_('titleHeight'); |
| 350 | this.area.y += this.attr_('titleHeight'); |
| 351 | } |
| 352 | if (this.attr_('xlabel')) { |
| 353 | this.area.h -= this.attr_('xLabelHeight'); |
| 354 | } |
| 355 | if (this.attr_('ylabel')) { |
| 356 | // It would make sense to shift the chart here to make room for the y-axis |
| 357 | // label, but the default yAxisLabelWidth is large enough that this results |
| 358 | // in overly-padded charts. The y-axis label should fit fine. If it |
| 359 | // doesn't, the yAxisLabelWidth option can be increased. |
| 360 | } |
| 361 | |
| 362 | this.container.style.position = "relative"; |
| 363 | this.container.style.width = this.width + "px"; |
| 364 | |
| 365 | // Set up a clipping area for the canvas (and the interaction canvas). |
| 366 | // This ensures that we don't overdraw. |
| 367 | var ctx = this.dygraph_.canvas_ctx_; |
| 368 | ctx.beginPath(); |
| 369 | ctx.rect(this.area.x, this.area.y, this.area.w, this.area.h); |
| 370 | ctx.clip(); |
| 371 | |
| 372 | ctx = this.dygraph_.hidden_ctx_; |
| 373 | ctx.beginPath(); |
| 374 | ctx.rect(this.area.x, this.area.y, this.area.w, this.area.h); |
| 375 | ctx.clip(); |
| 376 | }; |
| 377 | |
| 378 | DygraphCanvasRenderer.prototype.attr_ = function(x) { |
| 379 | return this.dygraph_.attr_(x); |
| 380 | }; |
| 381 | |
| 382 | DygraphCanvasRenderer.prototype.clear = function() { |
| 383 | if (this.isIE) { |
| 384 | // VML takes a while to start up, so we just poll every this.IEDelay |
| 385 | try { |
| 386 | if (this.clearDelay) { |
| 387 | this.clearDelay.cancel(); |
| 388 | this.clearDelay = null; |
| 389 | } |
| 390 | var context = this.elementContext; |
| 391 | } |
| 392 | catch (e) { |
| 393 | // TODO(danvk): this is broken, since MochiKit.Async is gone. |
| 394 | this.clearDelay = MochiKit.Async.wait(this.IEDelay); |
| 395 | this.clearDelay.addCallback(bind(this.clear, this)); |
| 396 | return; |
| 397 | } |
| 398 | } |
| 399 | |
| 400 | var context = this.elementContext; |
| 401 | context.clearRect(0, 0, this.width, this.height); |
| 402 | |
| 403 | for (var i = 0; i < this.xlabels.length; i++) { |
| 404 | var el = this.xlabels[i]; |
| 405 | if (el.parentNode) el.parentNode.removeChild(el); |
| 406 | } |
| 407 | for (var i = 0; i < this.ylabels.length; i++) { |
| 408 | var el = this.ylabels[i]; |
| 409 | if (el.parentNode) el.parentNode.removeChild(el); |
| 410 | } |
| 411 | for (var i = 0; i < this.annotations.length; i++) { |
| 412 | var el = this.annotations[i]; |
| 413 | if (el.parentNode) el.parentNode.removeChild(el); |
| 414 | } |
| 415 | for (var k in this.chartLabels) { |
| 416 | if (!this.chartLabels.hasOwnProperty(k)) continue; |
| 417 | var el = this.chartLabels[k]; |
| 418 | if (el.parentNode) el.parentNode.removeChild(el); |
| 419 | } |
| 420 | this.xlabels = new Array(); |
| 421 | this.ylabels = new Array(); |
| 422 | this.annotations = new Array(); |
| 423 | this.chartLabels = {}; |
| 424 | }; |
| 425 | |
| 426 | |
| 427 | DygraphCanvasRenderer.isSupported = function(canvasName) { |
| 428 | var canvas = null; |
| 429 | try { |
| 430 | if (typeof(canvasName) == 'undefined' || canvasName == null) |
| 431 | canvas = document.createElement("canvas"); |
| 432 | else |
| 433 | canvas = canvasName; |
| 434 | var context = canvas.getContext("2d"); |
| 435 | } |
| 436 | catch (e) { |
| 437 | var ie = navigator.appVersion.match(/MSIE (\d\.\d)/); |
| 438 | var opera = (navigator.userAgent.toLowerCase().indexOf("opera") != -1); |
| 439 | if ((!ie) || (ie[1] < 6) || (opera)) |
| 440 | return false; |
| 441 | return true; |
| 442 | } |
| 443 | return true; |
| 444 | }; |
| 445 | |
| 446 | /** |
| 447 | * Draw an X/Y grid on top of the existing plot |
| 448 | */ |
| 449 | DygraphCanvasRenderer.prototype.render = function() { |
| 450 | // Draw the new X/Y grid. Lines appear crisper when pixels are rounded to |
| 451 | // half-integers. This prevents them from drawing in two rows/cols. |
| 452 | var ctx = this.elementContext; |
| 453 | function halfUp(x){return Math.round(x)+0.5}; |
| 454 | function halfDown(y){return Math.round(y)-0.5}; |
| 455 | |
| 456 | if (this.options.underlayCallback) { |
| 457 | // NOTE: we pass the dygraph object to this callback twice to avoid breaking |
| 458 | // users who expect a deprecated form of this callback. |
| 459 | this.options.underlayCallback(ctx, this.area, this.dygraph_, this.dygraph_); |
| 460 | } |
| 461 | |
| 462 | if (this.options.drawYGrid) { |
| 463 | var ticks = this.layout.yticks; |
| 464 | ctx.save(); |
| 465 | ctx.strokeStyle = this.options.gridLineColor; |
| 466 | ctx.lineWidth = this.options.axisLineWidth; |
| 467 | for (var i = 0; i < ticks.length; i++) { |
| 468 | // TODO(danvk): allow secondary axes to draw a grid, too. |
| 469 | if (ticks[i][0] != 0) continue; |
| 470 | var x = halfUp(this.area.x); |
| 471 | var y = halfDown(this.area.y + ticks[i][1] * this.area.h); |
| 472 | ctx.beginPath(); |
| 473 | ctx.moveTo(x, y); |
| 474 | ctx.lineTo(x + this.area.w, y); |
| 475 | ctx.closePath(); |
| 476 | ctx.stroke(); |
| 477 | } |
| 478 | } |
| 479 | |
| 480 | if (this.options.drawXGrid) { |
| 481 | var ticks = this.layout.xticks; |
| 482 | ctx.save(); |
| 483 | ctx.strokeStyle = this.options.gridLineColor; |
| 484 | ctx.lineWidth = this.options.axisLineWidth; |
| 485 | for (var i=0; i<ticks.length; i++) { |
| 486 | var x = halfUp(this.area.x + ticks[i][0] * this.area.w); |
| 487 | var y = halfDown(this.area.y + this.area.h); |
| 488 | ctx.beginPath(); |
| 489 | ctx.moveTo(x, y); |
| 490 | ctx.lineTo(x, this.area.y); |
| 491 | ctx.closePath(); |
| 492 | ctx.stroke(); |
| 493 | } |
| 494 | } |
| 495 | |
| 496 | // Do the ordinary rendering, as before |
| 497 | this._renderLineChart(); |
| 498 | this._renderAxis(); |
| 499 | this._renderChartLabels(); |
| 500 | this._renderAnnotations(); |
| 501 | }; |
| 502 | |
| 503 | |
| 504 | DygraphCanvasRenderer.prototype._renderAxis = function() { |
| 505 | if (!this.options.drawXAxis && !this.options.drawYAxis) |
| 506 | return; |
| 507 | |
| 508 | // Round pixels to half-integer boundaries for crisper drawing. |
| 509 | function halfUp(x){return Math.round(x)+0.5}; |
| 510 | function halfDown(y){return Math.round(y)-0.5}; |
| 511 | |
| 512 | var context = this.elementContext; |
| 513 | |
| 514 | var labelStyle = { |
| 515 | "position": "absolute", |
| 516 | "fontSize": this.options.axisLabelFontSize + "px", |
| 517 | "zIndex": 10, |
| 518 | "color": this.options.axisLabelColor, |
| 519 | "width": this.options.axisLabelWidth + "px", |
| 520 | "overflow": "hidden" |
| 521 | }; |
| 522 | var makeDiv = function(txt) { |
| 523 | var div = document.createElement("div"); |
| 524 | for (var name in labelStyle) { |
| 525 | if (labelStyle.hasOwnProperty(name)) { |
| 526 | div.style[name] = labelStyle[name]; |
| 527 | } |
| 528 | } |
| 529 | div.appendChild(document.createTextNode(txt)); |
| 530 | return div; |
| 531 | }; |
| 532 | |
| 533 | // axis lines |
| 534 | context.save(); |
| 535 | context.strokeStyle = this.options.axisLineColor; |
| 536 | context.lineWidth = this.options.axisLineWidth; |
| 537 | |
| 538 | if (this.options.drawYAxis) { |
| 539 | if (this.layout.yticks && this.layout.yticks.length > 0) { |
| 540 | for (var i = 0; i < this.layout.yticks.length; i++) { |
| 541 | var tick = this.layout.yticks[i]; |
| 542 | if (typeof(tick) == "function") return; |
| 543 | var x = this.area.x; |
| 544 | var sgn = 1; |
| 545 | if (tick[0] == 1) { // right-side y-axis |
| 546 | x = this.area.x + this.area.w; |
| 547 | sgn = -1; |
| 548 | } |
| 549 | var y = this.area.y + tick[1] * this.area.h; |
| 550 | context.beginPath(); |
| 551 | context.moveTo(halfUp(x), halfDown(y)); |
| 552 | context.lineTo(halfUp(x - sgn * this.options.axisTickSize), halfDown(y)); |
| 553 | context.closePath(); |
| 554 | context.stroke(); |
| 555 | |
| 556 | var label = makeDiv(tick[2]); |
| 557 | var top = (y - this.options.axisLabelFontSize / 2); |
| 558 | if (top < 0) top = 0; |
| 559 | |
| 560 | if (top + this.options.axisLabelFontSize + 3 > this.height) { |
| 561 | label.style.bottom = "0px"; |
| 562 | } else { |
| 563 | label.style.top = top + "px"; |
| 564 | } |
| 565 | if (tick[0] == 0) { |
| 566 | label.style.left = (this.area.x - this.options.yAxisLabelWidth - this.options.axisTickSize) + "px"; |
| 567 | label.style.textAlign = "right"; |
| 568 | } else if (tick[0] == 1) { |
| 569 | label.style.left = (this.area.x + this.area.w + |
| 570 | this.options.axisTickSize) + "px"; |
| 571 | label.style.textAlign = "left"; |
| 572 | } |
| 573 | label.style.width = this.options.yAxisLabelWidth + "px"; |
| 574 | this.container.appendChild(label); |
| 575 | this.ylabels.push(label); |
| 576 | } |
| 577 | |
| 578 | // The lowest tick on the y-axis often overlaps with the leftmost |
| 579 | // tick on the x-axis. Shift the bottom tick up a little bit to |
| 580 | // compensate if necessary. |
| 581 | var bottomTick = this.ylabels[0]; |
| 582 | var fontSize = this.options.axisLabelFontSize; |
| 583 | var bottom = parseInt(bottomTick.style.top) + fontSize; |
| 584 | if (bottom > this.height - fontSize) { |
| 585 | bottomTick.style.top = (parseInt(bottomTick.style.top) - |
| 586 | fontSize / 2) + "px"; |
| 587 | } |
| 588 | } |
| 589 | |
| 590 | // draw a vertical line on the left to separate the chart from the labels. |
| 591 | context.beginPath(); |
| 592 | context.moveTo(halfUp(this.area.x), halfDown(this.area.y)); |
| 593 | context.lineTo(halfUp(this.area.x), halfDown(this.area.y + this.area.h)); |
| 594 | context.closePath(); |
| 595 | context.stroke(); |
| 596 | |
| 597 | // if there's a secondary y-axis, draw a vertical line for that, too. |
| 598 | if (this.dygraph_.numAxes() == 2) { |
| 599 | context.beginPath(); |
| 600 | context.moveTo(halfDown(this.area.x + this.area.w), halfDown(this.area.y)); |
| 601 | context.lineTo(halfDown(this.area.x + this.area.w), halfDown(this.area.y + this.area.h)); |
| 602 | context.closePath(); |
| 603 | context.stroke(); |
| 604 | } |
| 605 | } |
| 606 | |
| 607 | if (this.options.drawXAxis) { |
| 608 | if (this.layout.xticks) { |
| 609 | for (var i = 0; i < this.layout.xticks.length; i++) { |
| 610 | var tick = this.layout.xticks[i]; |
| 611 | if (typeof(dataset) == "function") return; |
| 612 | |
| 613 | var x = this.area.x + tick[0] * this.area.w; |
| 614 | var y = this.area.y + this.area.h; |
| 615 | context.beginPath(); |
| 616 | context.moveTo(halfUp(x), halfDown(y)); |
| 617 | context.lineTo(halfUp(x), halfDown(y + this.options.axisTickSize)); |
| 618 | context.closePath(); |
| 619 | context.stroke(); |
| 620 | |
| 621 | var label = makeDiv(tick[1]); |
| 622 | label.style.textAlign = "center"; |
| 623 | label.style.top = (y + this.options.axisTickSize) + 'px'; |
| 624 | |
| 625 | var left = (x - this.options.axisLabelWidth/2); |
| 626 | if (left + this.options.axisLabelWidth > this.width) { |
| 627 | left = this.width - this.options.xAxisLabelWidth; |
| 628 | label.style.textAlign = "right"; |
| 629 | } |
| 630 | if (left < 0) { |
| 631 | left = 0; |
| 632 | label.style.textAlign = "left"; |
| 633 | } |
| 634 | |
| 635 | label.style.left = left + "px"; |
| 636 | label.style.width = this.options.xAxisLabelWidth + "px"; |
| 637 | this.container.appendChild(label); |
| 638 | this.xlabels.push(label); |
| 639 | } |
| 640 | } |
| 641 | |
| 642 | context.beginPath(); |
| 643 | context.moveTo(halfUp(this.area.x), halfDown(this.area.y + this.area.h)); |
| 644 | context.lineTo(halfUp(this.area.x + this.area.w), halfDown(this.area.y + this.area.h)); |
| 645 | context.closePath(); |
| 646 | context.stroke(); |
| 647 | } |
| 648 | |
| 649 | context.restore(); |
| 650 | }; |
| 651 | |
| 652 | |
| 653 | DygraphCanvasRenderer.prototype._renderChartLabels = function() { |
| 654 | // Generate divs for the chart title, xlabel and ylabel. |
| 655 | // Space for these divs has already been taken away from the charting area in |
| 656 | // the DygraphCanvasRenderer constructor. |
| 657 | if (this.attr_('title')) { |
| 658 | var div = document.createElement("div"); |
| 659 | div.style.position = 'absolute'; |
| 660 | div.style.top = '0px'; |
| 661 | div.style.left = this.area.x + 'px'; |
| 662 | div.style.width = this.area.w + 'px'; |
| 663 | div.style.height = this.attr_('titleHeight') + 'px'; |
| 664 | div.style.textAlign = 'center'; |
| 665 | div.style.fontSize = (this.attr_('titleHeight') - 8) + 'px'; |
| 666 | div.style.fontWeight = 'bold'; |
| 667 | var class_div = document.createElement("div"); |
| 668 | class_div.className = 'dygraph-label dygraph-title'; |
| 669 | class_div.innerHTML = this.attr_('title'); |
| 670 | div.appendChild(class_div); |
| 671 | this.container.appendChild(div); |
| 672 | this.chartLabels.title = div; |
| 673 | } |
| 674 | |
| 675 | if (this.attr_('xlabel')) { |
| 676 | var div = document.createElement("div"); |
| 677 | div.style.position = 'absolute'; |
| 678 | div.style.bottom = 0; // TODO(danvk): this is lazy. Calculate style.top. |
| 679 | div.style.left = this.area.x + 'px'; |
| 680 | div.style.width = this.area.w + 'px'; |
| 681 | div.style.height = this.attr_('xLabelHeight') + 'px'; |
| 682 | div.style.textAlign = 'center'; |
| 683 | div.style.fontSize = (this.attr_('xLabelHeight') - 2) + 'px'; |
| 684 | |
| 685 | var class_div = document.createElement("div"); |
| 686 | class_div.className = 'dygraph-label dygraph-xlabel'; |
| 687 | class_div.innerHTML = this.attr_('xlabel'); |
| 688 | div.appendChild(class_div); |
| 689 | this.container.appendChild(div); |
| 690 | this.chartLabels.xlabel = div; |
| 691 | } |
| 692 | |
| 693 | if (this.attr_('ylabel')) { |
| 694 | var box = { |
| 695 | left: 0, |
| 696 | top: this.area.y, |
| 697 | width: this.attr_('yLabelWidth'), |
| 698 | height: this.area.h |
| 699 | }; |
| 700 | // TODO(danvk): is this outer div actually necessary? |
| 701 | var div = document.createElement("div"); |
| 702 | div.style.position = 'absolute'; |
| 703 | div.style.left = box.left; |
| 704 | div.style.top = box.top + 'px'; |
| 705 | div.style.width = box.width + 'px'; |
| 706 | div.style.height = box.height + 'px'; |
| 707 | div.style.fontSize = (this.attr_('yLabelWidth') - 2) + 'px'; |
| 708 | |
| 709 | var inner_div = document.createElement("div"); |
| 710 | inner_div.style.position = 'absolute'; |
| 711 | inner_div.style.width = box.height + 'px'; |
| 712 | inner_div.style.height = box.width + 'px'; |
| 713 | inner_div.style.top = (box.height / 2 - box.width / 2) + 'px'; |
| 714 | inner_div.style.left = (box.width / 2 - box.height / 2) + 'px'; |
| 715 | inner_div.style.textAlign = 'center'; |
| 716 | |
| 717 | // CSS rotation is an HTML5 feature which is not standardized. Hence every |
| 718 | // browser has its own name for the CSS style. |
| 719 | inner_div.style.transform = 'rotate(-90deg)'; // HTML5 |
| 720 | inner_div.style.WebkitTransform = 'rotate(-90deg)'; // Safari/Chrome |
| 721 | inner_div.style.MozTransform = 'rotate(-90deg)'; // Firefox |
| 722 | inner_div.style.OTransform = 'rotate(-90deg)'; // Opera |
| 723 | inner_div.style.msTransform = 'rotate(-90deg)'; // IE9 |
| 724 | |
| 725 | if (typeof(document.documentMode) !== 'undefined' && |
| 726 | document.documentMode < 9) { |
| 727 | // We're dealing w/ an old version of IE, so we have to rotate the text |
| 728 | // using a BasicImage transform. This uses a different origin of rotation |
| 729 | // than HTML5 rotation (top left of div vs. its center). |
| 730 | inner_div.style.filter = |
| 731 | 'progid:DXImageTransform.Microsoft.BasicImage(rotation=3)'; |
| 732 | inner_div.style.left = '0px'; |
| 733 | inner_div.style.top = '0px'; |
| 734 | } |
| 735 | |
| 736 | var class_div = document.createElement("div"); |
| 737 | class_div.className = 'dygraph-label dygraph-ylabel'; |
| 738 | class_div.innerHTML = this.attr_('ylabel'); |
| 739 | |
| 740 | inner_div.appendChild(class_div); |
| 741 | div.appendChild(inner_div); |
| 742 | this.container.appendChild(div); |
| 743 | this.chartLabels.ylabel = div; |
| 744 | } |
| 745 | }; |
| 746 | |
| 747 | |
| 748 | DygraphCanvasRenderer.prototype._renderAnnotations = function() { |
| 749 | var annotationStyle = { |
| 750 | "position": "absolute", |
| 751 | "fontSize": this.options.axisLabelFontSize + "px", |
| 752 | "zIndex": 10, |
| 753 | "overflow": "hidden" |
| 754 | }; |
| 755 | |
| 756 | var bindEvt = function(eventName, classEventName, p, self) { |
| 757 | return function(e) { |
| 758 | var a = p.annotation; |
| 759 | if (a.hasOwnProperty(eventName)) { |
| 760 | a[eventName](a, p, self.dygraph_, e); |
| 761 | } else if (self.dygraph_.attr_(classEventName)) { |
| 762 | self.dygraph_.attr_(classEventName)(a, p, self.dygraph_,e ); |
| 763 | } |
| 764 | }; |
| 765 | } |
| 766 | |
| 767 | // Get a list of point with annotations. |
| 768 | var points = this.layout.annotated_points; |
| 769 | for (var i = 0; i < points.length; i++) { |
| 770 | var p = points[i]; |
| 771 | if (p.canvasx < this.area.x || p.canvasx > this.area.x + this.area.w) { |
| 772 | continue; |
| 773 | } |
| 774 | |
| 775 | var a = p.annotation; |
| 776 | var tick_height = 6; |
| 777 | if (a.hasOwnProperty("tickHeight")) { |
| 778 | tick_height = a.tickHeight; |
| 779 | } |
| 780 | |
| 781 | var div = document.createElement("div"); |
| 782 | for (var name in annotationStyle) { |
| 783 | if (annotationStyle.hasOwnProperty(name)) { |
| 784 | div.style[name] = annotationStyle[name]; |
| 785 | } |
| 786 | } |
| 787 | if (!a.hasOwnProperty('icon')) { |
| 788 | div.className = "dygraphDefaultAnnotation"; |
| 789 | } |
| 790 | if (a.hasOwnProperty('cssClass')) { |
| 791 | div.className += " " + a.cssClass; |
| 792 | } |
| 793 | |
| 794 | var width = a.hasOwnProperty('width') ? a.width : 16; |
| 795 | var height = a.hasOwnProperty('height') ? a.height : 16; |
| 796 | if (a.hasOwnProperty('icon')) { |
| 797 | var img = document.createElement("img"); |
| 798 | img.src = a.icon; |
| 799 | img.width = width; |
| 800 | img.height = height; |
| 801 | div.appendChild(img); |
| 802 | } else if (p.annotation.hasOwnProperty('shortText')) { |
| 803 | div.appendChild(document.createTextNode(p.annotation.shortText)); |
| 804 | } |
| 805 | div.style.left = (p.canvasx - width / 2) + "px"; |
| 806 | if (a.attachAtBottom) { |
| 807 | div.style.top = (this.area.h - height - tick_height) + "px"; |
| 808 | } else { |
| 809 | div.style.top = (p.canvasy - height - tick_height) + "px"; |
| 810 | } |
| 811 | div.style.width = width + "px"; |
| 812 | div.style.height = height + "px"; |
| 813 | div.title = p.annotation.text; |
| 814 | div.style.color = this.colors[p.name]; |
| 815 | div.style.borderColor = this.colors[p.name]; |
| 816 | a.div = div; |
| 817 | |
| 818 | Dygraph.addEvent(div, 'click', |
| 819 | bindEvt('clickHandler', 'annotationClickHandler', p, this)); |
| 820 | Dygraph.addEvent(div, 'mouseover', |
| 821 | bindEvt('mouseOverHandler', 'annotationMouseOverHandler', p, this)); |
| 822 | Dygraph.addEvent(div, 'mouseout', |
| 823 | bindEvt('mouseOutHandler', 'annotationMouseOutHandler', p, this)); |
| 824 | Dygraph.addEvent(div, 'dblclick', |
| 825 | bindEvt('dblClickHandler', 'annotationDblClickHandler', p, this)); |
| 826 | |
| 827 | this.container.appendChild(div); |
| 828 | this.annotations.push(div); |
| 829 | |
| 830 | var ctx = this.elementContext; |
| 831 | ctx.strokeStyle = this.colors[p.name]; |
| 832 | ctx.beginPath(); |
| 833 | if (!a.attachAtBottom) { |
| 834 | ctx.moveTo(p.canvasx, p.canvasy); |
| 835 | ctx.lineTo(p.canvasx, p.canvasy - 2 - tick_height); |
| 836 | } else { |
| 837 | ctx.moveTo(p.canvasx, this.area.h); |
| 838 | ctx.lineTo(p.canvasx, this.area.h - 2 - tick_height); |
| 839 | } |
| 840 | ctx.closePath(); |
| 841 | ctx.stroke(); |
| 842 | } |
| 843 | }; |
| 844 | |
| 845 | |
| 846 | /** |
| 847 | * Overrides the CanvasRenderer method to draw error bars |
| 848 | */ |
| 849 | DygraphCanvasRenderer.prototype._renderLineChart = function() { |
| 850 | // TODO(danvk): use this.attr_ for many of these. |
| 851 | var context = this.elementContext; |
| 852 | var colorCount = this.options.colorScheme.length; |
| 853 | var colorScheme = this.options.colorScheme; |
| 854 | var fillAlpha = this.options.fillAlpha; |
| 855 | var errorBars = this.layout.options.errorBars; |
| 856 | var fillGraph = this.attr_("fillGraph"); |
| 857 | var stackedGraph = this.layout.options.stackedGraph; |
| 858 | var stepPlot = this.layout.options.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 | this.colors = {} |
| 869 | for (var i = 0; i < setCount; i++) { |
| 870 | this.colors[setNames[i]] = colorScheme[i % colorCount]; |
| 871 | } |
| 872 | |
| 873 | // Update Points |
| 874 | // TODO(danvk): here |
| 875 | for (var i = 0; i < this.layout.points.length; i++) { |
| 876 | var point = this.layout.points[i]; |
| 877 | point.canvasx = this.area.w * point.x + this.area.x; |
| 878 | point.canvasy = this.area.h * point.y + this.area.y; |
| 879 | } |
| 880 | |
| 881 | // create paths |
| 882 | var ctx = context; |
| 883 | if (errorBars) { |
| 884 | if (fillGraph) { |
| 885 | this.dygraph_.warn("Can't use fillGraph option with error bars"); |
| 886 | } |
| 887 | |
| 888 | for (var i = 0; i < setCount; i++) { |
| 889 | var setName = setNames[i]; |
| 890 | var axis = this.layout.options.yAxes[ |
| 891 | this.layout.options.seriesToAxisMap[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.layout.options.yAxes[ |
| 954 | this.layout.options.seriesToAxisMap[setName]]; |
| 955 | var axisY = 1.0 + axis.minyval * axis.yscale; |
| 956 | if (axisY < 0.0) axisY = 0.0; |
| 957 | else if (axisY > 1.0) axisY = 1.0; |
| 958 | axisY = this.area.h * axisY + this.area.y; |
| 959 | |
| 960 | // setup graphics context |
| 961 | ctx.save(); |
| 962 | var prevX = NaN; |
| 963 | var prevYs = [-1, -1]; |
| 964 | var yscale = axis.yscale; |
| 965 | // should be same color as the lines but only 15% opaque. |
| 966 | var rgb = new RGBColor(color); |
| 967 | var err_color = 'rgba(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ',' + |
| 968 | fillAlpha + ')'; |
| 969 | ctx.fillStyle = err_color; |
| 970 | ctx.beginPath(); |
| 971 | for (var j = 0; j < this.layout.points.length; j++) { |
| 972 | var point = this.layout.points[j]; |
| 973 | if (point.name == setName) { |
| 974 | if (!Dygraph.isOK(point.y)) { |
| 975 | prevX = NaN; |
| 976 | continue; |
| 977 | } |
| 978 | var newYs; |
| 979 | if (stackedGraph) { |
| 980 | lastY = baseline[point.canvasx]; |
| 981 | if (lastY === undefined) lastY = axisY; |
| 982 | baseline[point.canvasx] = point.canvasy; |
| 983 | newYs = [ point.canvasy, lastY ]; |
| 984 | } else { |
| 985 | newYs = [ point.canvasy, axisY ]; |
| 986 | } |
| 987 | if (!isNaN(prevX)) { |
| 988 | ctx.moveTo(prevX, prevYs[0]); |
| 989 | if (stepPlot) { |
| 990 | ctx.lineTo(point.canvasx, prevYs[0]); |
| 991 | } else { |
| 992 | ctx.lineTo(point.canvasx, newYs[0]); |
| 993 | } |
| 994 | ctx.lineTo(point.canvasx, newYs[1]); |
| 995 | ctx.lineTo(prevX, prevYs[1]); |
| 996 | ctx.closePath(); |
| 997 | } |
| 998 | prevYs = newYs; |
| 999 | prevX = point.canvasx; |
| 1000 | } |
| 1001 | } |
| 1002 | ctx.fill(); |
| 1003 | } |
| 1004 | } |
| 1005 | |
| 1006 | for (var i = 0; i < setCount; i++) { |
| 1007 | var setName = setNames[i]; |
| 1008 | var color = this.colors[setName]; |
| 1009 | var strokeWidth = this.dygraph_.attr_("strokeWidth", setName); |
| 1010 | |
| 1011 | // setup graphics context |
| 1012 | context.save(); |
| 1013 | var point = this.layout.points[0]; |
| 1014 | var pointSize = this.dygraph_.attr_("pointSize", setName); |
| 1015 | var prevX = null, prevY = null; |
| 1016 | var drawPoints = this.dygraph_.attr_("drawPoints", setName); |
| 1017 | var points = this.layout.points; |
| 1018 | for (var j = 0; j < points.length; j++) { |
| 1019 | var point = points[j]; |
| 1020 | if (point.name == setName) { |
| 1021 | if (!Dygraph.isOK(point.canvasy)) { |
| 1022 | if (stepPlot && prevX != null) { |
| 1023 | // Draw a horizontal line to the start of the missing data |
| 1024 | ctx.beginPath(); |
| 1025 | ctx.strokeStyle = color; |
| 1026 | ctx.lineWidth = this.options.strokeWidth; |
| 1027 | ctx.moveTo(prevX, prevY); |
| 1028 | ctx.lineTo(point.canvasx, prevY); |
| 1029 | ctx.stroke(); |
| 1030 | } |
| 1031 | // this will make us move to the next point, not draw a line to it. |
| 1032 | prevX = prevY = null; |
| 1033 | } else { |
| 1034 | // A point is "isolated" if it is non-null but both the previous |
| 1035 | // and next points are null. |
| 1036 | var isIsolated = (!prevX && (j == points.length - 1 || |
| 1037 | !Dygraph.isOK(points[j+1].canvasy))); |
| 1038 | |
| 1039 | if (!prevX) { |
| 1040 | prevX = point.canvasx; |
| 1041 | prevY = point.canvasy; |
| 1042 | } else { |
| 1043 | // TODO(danvk): figure out why this conditional is necessary. |
| 1044 | if (strokeWidth) { |
| 1045 | ctx.beginPath(); |
| 1046 | ctx.strokeStyle = color; |
| 1047 | ctx.lineWidth = strokeWidth; |
| 1048 | ctx.moveTo(prevX, prevY); |
| 1049 | if (stepPlot) { |
| 1050 | ctx.lineTo(point.canvasx, prevY); |
| 1051 | } |
| 1052 | prevX = point.canvasx; |
| 1053 | prevY = point.canvasy; |
| 1054 | ctx.lineTo(prevX, prevY); |
| 1055 | ctx.stroke(); |
| 1056 | } |
| 1057 | } |
| 1058 | |
| 1059 | if (drawPoints || isIsolated) { |
| 1060 | ctx.beginPath(); |
| 1061 | ctx.fillStyle = color; |
| 1062 | ctx.arc(point.canvasx, point.canvasy, pointSize, |
| 1063 | 0, 2 * Math.PI, false); |
| 1064 | ctx.fill(); |
| 1065 | } |
| 1066 | } |
| 1067 | } |
| 1068 | } |
| 1069 | } |
| 1070 | |
| 1071 | context.restore(); |
| 1072 | }; |