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88e95c46 DV |
1 | /** |
2 | * @license | |
3 | * Copyright 2006 Dan Vanderkam (danvdk@gmail.com) | |
4 | * MIT-licensed (http://opensource.org/licenses/MIT) | |
5 | */ | |
6a1aa64f DV |
6 | |
7 | /** | |
74a5af31 DV |
8 | * @fileoverview Based on PlotKit.CanvasRenderer, but modified to meet the |
9 | * needs of dygraphs. | |
10 | * | |
3df0ccf0 | 11 | * In particular, support for: |
0abfbd7e | 12 | * - grid overlays |
3df0ccf0 DV |
13 | * - error bars |
14 | * - dygraphs attribute system | |
6a1aa64f DV |
15 | */ |
16 | ||
6a1aa64f | 17 | /** |
423f5ed3 DV |
18 | * The DygraphCanvasRenderer class does the actual rendering of the chart onto |
19 | * a canvas. It's based on PlotKit.CanvasRenderer. | |
6a1aa64f | 20 | * @param {Object} element The canvas to attach to |
2cf95fff RK |
21 | * @param {Object} elementContext The 2d context of the canvas (injected so it |
22 | * can be mocked for testing.) | |
285a6bda | 23 | * @param {Layout} layout The DygraphLayout object for this graph. |
74a5af31 | 24 | * @constructor |
6a1aa64f | 25 | */ |
c0f54d4f | 26 | |
758a629f DV |
27 | /*jshint globalstrict: true */ |
28 | /*global Dygraph:false,RGBColor:false */ | |
c0f54d4f DV |
29 | "use strict"; |
30 | ||
79253bd0 | 31 | |
8cfe592f DV |
32 | /** |
33 | * @constructor | |
34 | * | |
35 | * This gets called when there are "new points" to chart. This is generally the | |
36 | * case when the underlying data being charted has changed. It is _not_ called | |
37 | * in the common case that the user has zoomed or is panning the view. | |
38 | * | |
39 | * The chart canvas has already been created by the Dygraph object. The | |
40 | * renderer simply gets a drawing context. | |
41 | * | |
42 | * @param {Dyraph} dygraph The chart to which this renderer belongs. | |
43 | * @param {Canvas} element The <canvas> DOM element on which to draw. | |
44 | * @param {CanvasRenderingContext2D} elementContext The drawing context. | |
45 | * @param {DygraphLayout} layout The chart's DygraphLayout object. | |
46 | * | |
47 | * TODO(danvk): remove the elementContext property. | |
48 | */ | |
c0f54d4f | 49 | var DygraphCanvasRenderer = function(dygraph, element, elementContext, layout) { |
9317362d | 50 | this.dygraph_ = dygraph; |
fbe31dc8 | 51 | |
fbe31dc8 | 52 | this.layout = layout; |
b0c3b730 | 53 | this.element = element; |
2cf95fff | 54 | this.elementContext = elementContext; |
fbe31dc8 DV |
55 | this.container = this.element.parentNode; |
56 | ||
fbe31dc8 DV |
57 | this.height = this.element.height; |
58 | this.width = this.element.width; | |
59 | ||
60 | // --- check whether everything is ok before we return | |
61 | if (!this.isIE && !(DygraphCanvasRenderer.isSupported(this.element))) | |
62 | throw "Canvas is not supported."; | |
63 | ||
64 | // internal state | |
70be5ed1 | 65 | this.area = layout.getPlotArea(); |
423f5ed3 DV |
66 | this.container.style.position = "relative"; |
67 | this.container.style.width = this.width + "px"; | |
68 | ||
69 | // Set up a clipping area for the canvas (and the interaction canvas). | |
70 | // This ensures that we don't overdraw. | |
920208fb PF |
71 | if (this.dygraph_.isUsingExcanvas_) { |
72 | this._createIEClipArea(); | |
73 | } else { | |
971870e5 DV |
74 | // on Android 3 and 4, setting a clipping area on a canvas prevents it from |
75 | // displaying anything. | |
76 | if (!Dygraph.isAndroid()) { | |
77 | var ctx = this.dygraph_.canvas_ctx_; | |
78 | ctx.beginPath(); | |
79 | ctx.rect(this.area.x, this.area.y, this.area.w, this.area.h); | |
80 | ctx.clip(); | |
920208fb | 81 | |
971870e5 DV |
82 | ctx = this.dygraph_.hidden_ctx_; |
83 | ctx.beginPath(); | |
84 | ctx.rect(this.area.x, this.area.y, this.area.w, this.area.h); | |
85 | ctx.clip(); | |
86 | } | |
920208fb | 87 | } |
423f5ed3 DV |
88 | }; |
89 | ||
90 | DygraphCanvasRenderer.prototype.attr_ = function(x) { | |
91 | return this.dygraph_.attr_(x); | |
92 | }; | |
93 | ||
8cfe592f DV |
94 | /** |
95 | * Clears out all chart content and DOM elements. | |
96 | * This is called immediately before render() on every frame, including | |
97 | * during zooms and pans. | |
98 | * @private | |
99 | */ | |
fbe31dc8 | 100 | DygraphCanvasRenderer.prototype.clear = function() { |
758a629f | 101 | var context; |
fbe31dc8 DV |
102 | if (this.isIE) { |
103 | // VML takes a while to start up, so we just poll every this.IEDelay | |
104 | try { | |
105 | if (this.clearDelay) { | |
106 | this.clearDelay.cancel(); | |
107 | this.clearDelay = null; | |
108 | } | |
758a629f | 109 | context = this.elementContext; |
fbe31dc8 DV |
110 | } |
111 | catch (e) { | |
76171648 | 112 | // TODO(danvk): this is broken, since MochiKit.Async is gone. |
758a629f DV |
113 | // this.clearDelay = MochiKit.Async.wait(this.IEDelay); |
114 | // this.clearDelay.addCallback(bind(this.clear, this)); | |
fbe31dc8 DV |
115 | return; |
116 | } | |
117 | } | |
118 | ||
758a629f | 119 | context = this.elementContext; |
fbe31dc8 | 120 | context.clearRect(0, 0, this.width, this.height); |
fbe31dc8 DV |
121 | }; |
122 | ||
8cfe592f DV |
123 | /** |
124 | * Checks whether the browser supports the <canvas> tag. | |
125 | * @private | |
126 | */ | |
fbe31dc8 DV |
127 | DygraphCanvasRenderer.isSupported = function(canvasName) { |
128 | var canvas = null; | |
129 | try { | |
758a629f | 130 | if (typeof(canvasName) == 'undefined' || canvasName === null) { |
b0c3b730 | 131 | canvas = document.createElement("canvas"); |
758a629f | 132 | } else { |
b0c3b730 | 133 | canvas = canvasName; |
758a629f DV |
134 | } |
135 | canvas.getContext("2d"); | |
fbe31dc8 DV |
136 | } |
137 | catch (e) { | |
138 | var ie = navigator.appVersion.match(/MSIE (\d\.\d)/); | |
139 | var opera = (navigator.userAgent.toLowerCase().indexOf("opera") != -1); | |
140 | if ((!ie) || (ie[1] < 6) || (opera)) | |
141 | return false; | |
142 | return true; | |
143 | } | |
144 | return true; | |
6a1aa64f | 145 | }; |
6a1aa64f DV |
146 | |
147 | /** | |
8cfe592f DV |
148 | * This method is responsible for drawing everything on the chart, including |
149 | * lines, error bars, fills and axes. | |
150 | * It is called immediately after clear() on every frame, including during pans | |
151 | * and zooms. | |
152 | * @private | |
6a1aa64f | 153 | */ |
285a6bda | 154 | DygraphCanvasRenderer.prototype.render = function() { |
2ce09b19 | 155 | this._renderLineChart(); |
fbe31dc8 DV |
156 | }; |
157 | ||
920208fb PF |
158 | DygraphCanvasRenderer.prototype._createIEClipArea = function() { |
159 | var className = 'dygraph-clip-div'; | |
160 | var graphDiv = this.dygraph_.graphDiv; | |
161 | ||
162 | // Remove old clip divs. | |
163 | for (var i = graphDiv.childNodes.length-1; i >= 0; i--) { | |
164 | if (graphDiv.childNodes[i].className == className) { | |
165 | graphDiv.removeChild(graphDiv.childNodes[i]); | |
166 | } | |
167 | } | |
168 | ||
169 | // Determine background color to give clip divs. | |
170 | var backgroundColor = document.bgColor; | |
171 | var element = this.dygraph_.graphDiv; | |
172 | while (element != document) { | |
173 | var bgcolor = element.currentStyle.backgroundColor; | |
174 | if (bgcolor && bgcolor != 'transparent') { | |
175 | backgroundColor = bgcolor; | |
176 | break; | |
177 | } | |
178 | element = element.parentNode; | |
179 | } | |
180 | ||
181 | function createClipDiv(area) { | |
758a629f | 182 | if (area.w === 0 || area.h === 0) { |
920208fb PF |
183 | return; |
184 | } | |
185 | var elem = document.createElement('div'); | |
186 | elem.className = className; | |
187 | elem.style.backgroundColor = backgroundColor; | |
188 | elem.style.position = 'absolute'; | |
189 | elem.style.left = area.x + 'px'; | |
190 | elem.style.top = area.y + 'px'; | |
191 | elem.style.width = area.w + 'px'; | |
192 | elem.style.height = area.h + 'px'; | |
193 | graphDiv.appendChild(elem); | |
194 | } | |
195 | ||
196 | var plotArea = this.area; | |
197 | // Left side | |
758a629f DV |
198 | createClipDiv({ |
199 | x:0, y:0, | |
200 | w:plotArea.x, | |
201 | h:this.height | |
202 | }); | |
203 | ||
920208fb | 204 | // Top |
758a629f DV |
205 | createClipDiv({ |
206 | x: plotArea.x, y: 0, | |
207 | w: this.width - plotArea.x, | |
208 | h: plotArea.y | |
209 | }); | |
210 | ||
920208fb | 211 | // Right side |
758a629f DV |
212 | createClipDiv({ |
213 | x: plotArea.x + plotArea.w, y: 0, | |
214 | w: this.width-plotArea.x - plotArea.w, | |
215 | h: this.height | |
216 | }); | |
217 | ||
920208fb | 218 | // Bottom |
758a629f DV |
219 | createClipDiv({ |
220 | x: plotArea.x, | |
221 | y: plotArea.y + plotArea.h, | |
222 | w: this.width - plotArea.x, | |
223 | h: this.height - plotArea.h - plotArea.y | |
224 | }); | |
225 | }; | |
fbe31dc8 | 226 | |
fbe31dc8 | 227 | |
ccb0001c | 228 | /** |
8722284b RK |
229 | * Returns a predicate to be used with an iterator, which will |
230 | * iterate over points appropriately, depending on whether | |
231 | * connectSeparatedPoints is true. When it's false, the predicate will | |
232 | * skip over points with missing yVals. | |
ccb0001c | 233 | */ |
8722284b | 234 | DygraphCanvasRenderer._getIteratorPredicate = function(connectSeparatedPoints) { |
9f6db80e DV |
235 | return connectSeparatedPoints |
236 | ? DygraphCanvasRenderer._predicateThatSkipsEmptyPoints | |
237 | : null; | |
0f20de1c | 238 | }; |
8722284b RK |
239 | |
240 | DygraphCanvasRenderer._predicateThatSkipsEmptyPoints = | |
0f20de1c DV |
241 | function(array, idx) { |
242 | return array[idx].yval !== null; | |
243 | }; | |
04c104d7 | 244 | |
9f6db80e DV |
245 | /** |
246 | * | |
247 | * @private | |
248 | */ | |
857a6931 | 249 | DygraphCanvasRenderer.prototype._drawStyledLine = function( |
a12a78ae | 250 | ctx, setIdx, setName, color, strokeWidth, strokePattern, drawPoints, |
5469113b | 251 | drawPointCallback, pointSize) { |
99a77a04 | 252 | // TODO(konigsberg): Compute attributes outside this method call. |
857a6931 | 253 | var stepPlot = this.attr_("stepPlot"); |
857a6931 KW |
254 | if (!Dygraph.isArrayLike(strokePattern)) { |
255 | strokePattern = null; | |
256 | } | |
a5a50727 | 257 | var drawGapPoints = this.dygraph_.attr_('drawGapEdgePoints', setName); |
857a6931 | 258 | |
a12a78ae DV |
259 | var points = this.layout.points[setIdx]; |
260 | var iter = Dygraph.createIterator(points, 0, points.length, | |
9f6db80e DV |
261 | DygraphCanvasRenderer._getIteratorPredicate( |
262 | this.attr_("connectSeparatedPoints"))); | |
7d1afbb9 | 263 | |
fb63bf1b DV |
264 | var stroking = strokePattern && (strokePattern.length >= 2); |
265 | ||
0140347d | 266 | ctx.save(); |
fb63bf1b DV |
267 | if (stroking) { |
268 | ctx.installPattern(strokePattern); | |
b843b52c | 269 | } |
fb63bf1b | 270 | |
0140347d | 271 | var pointsOnLine = this._drawSeries(ctx, iter, strokeWidth, pointSize, drawPoints, drawGapPoints, stepPlot, color); |
31f8e58b RK |
272 | this._drawPointsOnLine(ctx, pointsOnLine, drawPointCallback, setName, color, pointSize); |
273 | ||
fb63bf1b DV |
274 | if (stroking) { |
275 | ctx.uninstallPattern(); | |
276 | } | |
b843b52c | 277 | |
fb63bf1b | 278 | ctx.restore(); |
31f8e58b RK |
279 | }; |
280 | ||
a401ca8a RK |
281 | DygraphCanvasRenderer.prototype._drawPointsOnLine = function(ctx, pointsOnLine, drawPointCallback, setName, color, pointSize) { |
282 | for (var idx = 0; idx < pointsOnLine.length; idx++) { | |
283 | var cb = pointsOnLine[idx]; | |
284 | ctx.save(); | |
285 | drawPointCallback( | |
286 | this.dygraph_, setName, ctx, cb[0], cb[1], color, pointSize); | |
287 | ctx.restore(); | |
288 | } | |
289 | } | |
290 | ||
31f8e58b RK |
291 | DygraphCanvasRenderer.prototype._drawSeries = function( |
292 | ctx, iter, strokeWidth, pointSize, drawPoints, drawGapPoints, | |
0140347d | 293 | stepPlot, color) { |
31f8e58b | 294 | |
31f8e58b RK |
295 | var prevCanvasX = null; |
296 | var prevCanvasY = null; | |
297 | var nextCanvasY = null; | |
298 | var isIsolated; // true if this point is isolated (no line segments) | |
299 | var point; // the point being processed in the while loop | |
b843b52c | 300 | var pointsOnLine = []; // Array of [canvasx, canvasy] pairs. |
31f8e58b RK |
301 | var first = true; // the first cycle through the while loop |
302 | ||
0140347d DV |
303 | ctx.beginPath(); |
304 | ctx.strokeStyle = color; | |
305 | ctx.lineWidth = strokeWidth; | |
31f8e58b | 306 | |
239454e2 | 307 | // NOTE: we break the iterator's encapsulation here for about a 25% speedup. |
c560c848 DV |
308 | var arr = iter.array_; |
309 | var limit = iter.end_; | |
310 | var predicate = iter.predicate_; | |
311 | ||
312 | for (var i = iter.start_; i < limit; i++) { | |
313 | point = arr[i]; | |
314 | if (predicate) { | |
315 | while (i < limit && !predicate(arr, i)) { | |
0f20de1c DV |
316 | i++; |
317 | } | |
c560c848 DV |
318 | if (i == limit) break; |
319 | point = arr[i]; | |
0f20de1c DV |
320 | } |
321 | ||
a02978e2 | 322 | if (point.canvasy === null || point.canvasy != point.canvasy) { |
31f8e58b | 323 | if (stepPlot && prevCanvasX !== null) { |
857a6931 | 324 | // Draw a horizontal line to the start of the missing data |
0140347d DV |
325 | ctx.moveTo(prevX, prevY); |
326 | ctx.lineTo(point.canvasx, prevY); | |
857a6931 | 327 | } |
31f8e58b | 328 | prevCanvasX = prevCanvasY = null; |
857a6931 | 329 | } else { |
0f20de1c DV |
330 | isIsolated = false; |
331 | if (drawGapPoints || !prevCanvasX) { | |
0f20de1c DV |
332 | iter.nextIdx_ = i; |
333 | var peek = iter.next(); | |
82f9b10f | 334 | nextCanvasY = iter.hasNext ? iter.peek.canvasy : null; |
0f20de1c | 335 | |
0f20de1c DV |
336 | var isNextCanvasYNullOrNaN = nextCanvasY === null || |
337 | nextCanvasY != nextCanvasY; | |
338 | isIsolated = (!prevCanvasX && isNextCanvasYNullOrNaN); | |
339 | if (drawGapPoints) { | |
340 | // Also consider a point to be "isolated" if it's adjacent to a | |
341 | // null point, excluding the graph edges. | |
342 | if ((!first && !prevCanvasX) || | |
343 | (iter.hasNext && isNextCanvasYNullOrNaN)) { | |
344 | isIsolated = true; | |
345 | } | |
19b84fe7 KW |
346 | } |
347 | } | |
0f20de1c | 348 | |
31f8e58b | 349 | if (prevCanvasX !== null) { |
857a6931 | 350 | if (strokeWidth) { |
857a6931 | 351 | if (stepPlot) { |
0140347d DV |
352 | ctx.moveTo(prevCanvasX, prevCanvasY); |
353 | ctx.lineTo(point.canvasx, prevCanvasY); | |
31f8e58b | 354 | prevCanvasX = point.canvasx; |
857a6931 | 355 | } |
239454e2 DV |
356 | |
357 | // TODO(danvk): this moveTo is rarely necessary | |
0140347d DV |
358 | ctx.moveTo(prevCanvasX, prevCanvasY); |
359 | ctx.lineTo(point.canvasx, point.canvasy); | |
b843b52c RK |
360 | } |
361 | } | |
b843b52c RK |
362 | if (drawPoints || isIsolated) { |
363 | pointsOnLine.push([point.canvasx, point.canvasy]); | |
364 | } | |
31f8e58b RK |
365 | prevCanvasX = point.canvasx; |
366 | prevCanvasY = point.canvasy; | |
b843b52c | 367 | } |
7d1afbb9 | 368 | first = false; |
b843b52c | 369 | } |
0140347d | 370 | ctx.stroke(); |
31f8e58b | 371 | return pointsOnLine; |
857a6931 KW |
372 | }; |
373 | ||
374 | DygraphCanvasRenderer.prototype._drawLine = function(ctx, i) { | |
375 | var setNames = this.layout.setNames; | |
376 | var setName = setNames[i]; | |
377 | ||
378 | var strokeWidth = this.dygraph_.attr_("strokeWidth", setName); | |
379 | var borderWidth = this.dygraph_.attr_("strokeBorderWidth", setName); | |
5469113b KW |
380 | var drawPointCallback = this.dygraph_.attr_("drawPointCallback", setName) || |
381 | Dygraph.Circles.DEFAULT; | |
99a77a04 | 382 | |
857a6931 | 383 | if (borderWidth && strokeWidth) { |
5469113b | 384 | this._drawStyledLine(ctx, i, setName, |
857a6931 KW |
385 | this.dygraph_.attr_("strokeBorderColor", setName), |
386 | strokeWidth + 2 * borderWidth, | |
387 | this.dygraph_.attr_("strokePattern", setName), | |
388 | this.dygraph_.attr_("drawPoints", setName), | |
5469113b | 389 | drawPointCallback, |
857a6931 KW |
390 | this.dygraph_.attr_("pointSize", setName)); |
391 | } | |
392 | ||
5469113b | 393 | this._drawStyledLine(ctx, i, setName, |
857a6931 KW |
394 | this.colors[setName], |
395 | strokeWidth, | |
396 | this.dygraph_.attr_("strokePattern", setName), | |
397 | this.dygraph_.attr_("drawPoints", setName), | |
5469113b | 398 | drawPointCallback, |
857a6931 KW |
399 | this.dygraph_.attr_("pointSize", setName)); |
400 | }; | |
ce49c2fa | 401 | |
6a1aa64f | 402 | /** |
758a629f | 403 | * Actually draw the lines chart, including error bars. |
758a629f | 404 | * @private |
6a1aa64f | 405 | */ |
285a6bda | 406 | DygraphCanvasRenderer.prototype._renderLineChart = function() { |
857a6931 | 407 | var ctx = this.elementContext; |
e4182459 | 408 | var errorBars = this.attr_("errorBars") || this.attr_("customBars"); |
44c6bc29 | 409 | var fillGraph = this.attr_("fillGraph"); |
01a14b85 | 410 | var i; |
21d3323f | 411 | |
82c6fe4d | 412 | var setNames = this.layout.setNames; |
21d3323f | 413 | var setCount = setNames.length; |
6a1aa64f | 414 | |
ee53deb9 | 415 | this.colors = this.dygraph_.colorsMap_; |
f032c51d | 416 | |
ff00d3e2 DV |
417 | // Update Points |
418 | // TODO(danvk): here | |
b843b52c RK |
419 | // |
420 | // TODO(bhs): this loop is a hot-spot for high-point-count charts. These | |
421 | // transformations can be pushed into the canvas via linear transformation | |
422 | // matrices. | |
e60234cd DV |
423 | // NOTE(danvk): this is trickier than it sounds at first. The transformation |
424 | // needs to be done before the .moveTo() and .lineTo() calls, but must be | |
425 | // undone before the .stroke() call to ensure that the stroke width is | |
426 | // unaffected. An alternative is to reduce the stroke width in the | |
427 | // transformed coordinate space, but you can't specify different values for | |
428 | // each dimension (as you can with .scale()). The speedup here is ~12%. | |
a12a78ae DV |
429 | var sets = this.layout.points; |
430 | for (i = sets.length; i--;) { | |
431 | var points = sets[i]; | |
432 | for (var j = points.length; j--;) { | |
433 | var point = points[j]; | |
434 | point.canvasx = this.area.w * point.x + this.area.x; | |
435 | point.canvasy = this.area.h * point.y + this.area.y; | |
436 | } | |
6a1aa64f | 437 | } |
6a1aa64f | 438 | |
01a14b85 DV |
439 | // Draw any "fills", i.e. error bars or the filled area under a series. |
440 | // These must all be drawn before any lines, so that the main lines of a | |
441 | // series are drawn on top. | |
80aaae18 | 442 | if (errorBars) { |
6a834bbb DV |
443 | if (fillGraph) { |
444 | this.dygraph_.warn("Can't use fillGraph option with error bars"); | |
445 | } | |
446 | ||
01a14b85 | 447 | ctx.save(); |
6a6439da | 448 | this.drawErrorBars_(points); |
857a6931 | 449 | ctx.restore(); |
5954ef32 | 450 | } else if (fillGraph) { |
857a6931 | 451 | ctx.save(); |
01a14b85 | 452 | this.drawFillBars_(points); |
857a6931 | 453 | ctx.restore(); |
80aaae18 DV |
454 | } |
455 | ||
f9414b11 | 456 | // Drawing the lines. |
758a629f | 457 | for (i = 0; i < setCount; i += 1) { |
857a6931 | 458 | this._drawLine(ctx, i); |
80aaae18 | 459 | } |
6a1aa64f | 460 | }; |
79253bd0 | 461 | |
01a14b85 DV |
462 | /** |
463 | * Draws the shaded error bars/confidence intervals for each series. | |
464 | * This happens before the center lines are drawn, since the center lines | |
465 | * need to be drawn on top of the error bars for all series. | |
466 | * | |
467 | * @private | |
468 | */ | |
6a6439da DV |
469 | DygraphCanvasRenderer.prototype.drawErrorBars_ = function(points) { |
470 | var ctx = this.elementContext; | |
471 | var setNames = this.layout.setNames; | |
472 | var setCount = setNames.length; | |
473 | var fillAlpha = this.attr_('fillAlpha'); | |
01a14b85 | 474 | var stepPlot = this.attr_('stepPlot'); |
6a6439da DV |
475 | |
476 | var newYs; | |
477 | ||
478 | for (var i = 0; i < setCount; i++) { | |
479 | var setName = setNames[i]; | |
480 | var axis = this.dygraph_.axisPropertiesForSeries(setName); | |
481 | var color = this.colors[setName]; | |
482 | ||
483 | var firstIndexInSet = this.layout.setPointsOffsets[i]; | |
484 | var setLength = this.layout.setPointsLengths[i]; | |
485 | ||
486 | var iter = Dygraph.createIterator(points, firstIndexInSet, setLength, | |
01a14b85 DV |
487 | DygraphCanvasRenderer._getIteratorPredicate( |
488 | this.attr_("connectSeparatedPoints"))); | |
6a6439da DV |
489 | |
490 | // setup graphics context | |
491 | var prevX = NaN; | |
492 | var prevY = NaN; | |
493 | var prevYs = [-1, -1]; | |
494 | var yscale = axis.yscale; | |
495 | // should be same color as the lines but only 15% opaque. | |
496 | var rgb = new RGBColor(color); | |
497 | var err_color = | |
498 | 'rgba(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ',' + fillAlpha + ')'; | |
499 | ctx.fillStyle = err_color; | |
500 | ctx.beginPath(); | |
501 | while (iter.hasNext) { | |
502 | var point = iter.next(); | |
a5701188 DV |
503 | if (!Dygraph.isOK(point.y)) { |
504 | prevX = NaN; | |
505 | continue; | |
506 | } | |
6a6439da | 507 | |
a5701188 DV |
508 | if (stepPlot) { |
509 | newYs = [ point.y_bottom, point.y_top ]; | |
510 | prevY = point.y; | |
511 | } else { | |
512 | newYs = [ point.y_bottom, point.y_top ]; | |
513 | } | |
514 | newYs[0] = this.area.h * newYs[0] + this.area.y; | |
515 | newYs[1] = this.area.h * newYs[1] + this.area.y; | |
516 | if (!isNaN(prevX)) { | |
6a6439da | 517 | if (stepPlot) { |
a5701188 | 518 | ctx.moveTo(prevX, newYs[0]); |
6a6439da | 519 | } else { |
a5701188 | 520 | ctx.moveTo(prevX, prevYs[0]); |
6a6439da | 521 | } |
a5701188 DV |
522 | ctx.lineTo(point.canvasx, newYs[0]); |
523 | ctx.lineTo(point.canvasx, newYs[1]); | |
524 | if (stepPlot) { | |
525 | ctx.lineTo(prevX, newYs[1]); | |
526 | } else { | |
527 | ctx.lineTo(prevX, prevYs[1]); | |
6a6439da | 528 | } |
a5701188 | 529 | ctx.closePath(); |
6a6439da | 530 | } |
a5701188 DV |
531 | prevYs = newYs; |
532 | prevX = point.canvasx; | |
6a6439da DV |
533 | } |
534 | ctx.fill(); | |
535 | } | |
536 | }; | |
537 | ||
79253bd0 | 538 | /** |
01a14b85 DV |
539 | * Draws the shaded regions when "fillGraph" is set. Not to be confused with |
540 | * error bars. | |
541 | * | |
542 | * @private | |
543 | */ | |
544 | DygraphCanvasRenderer.prototype.drawFillBars_ = function(points) { | |
545 | var ctx = this.elementContext; | |
546 | var setNames = this.layout.setNames; | |
547 | var setCount = setNames.length; | |
548 | var fillAlpha = this.attr_('fillAlpha'); | |
549 | var stepPlot = this.attr_('stepPlot'); | |
550 | var stackedGraph = this.attr_("stackedGraph"); | |
551 | ||
552 | var baseline = {}; // for stacked graphs: baseline for filling | |
553 | var currBaseline; | |
554 | ||
555 | // process sets in reverse order (needed for stacked graphs) | |
9e85a8f4 DV |
556 | for (var setIdx = setCount - 1; setIdx >= 0; setIdx--) { |
557 | var setName = setNames[setIdx]; | |
01a14b85 DV |
558 | var color = this.colors[setName]; |
559 | var axis = this.dygraph_.axisPropertiesForSeries(setName); | |
560 | var axisY = 1.0 + axis.minyval * axis.yscale; | |
561 | if (axisY < 0.0) axisY = 0.0; | |
562 | else if (axisY > 1.0) axisY = 1.0; | |
563 | axisY = this.area.h * axisY + this.area.y; | |
01a14b85 | 564 | |
9e85a8f4 DV |
565 | var points = this.layout.points[setIdx]; |
566 | var iter = Dygraph.createIterator(points, 0, points.length, | |
01a14b85 DV |
567 | DygraphCanvasRenderer._getIteratorPredicate( |
568 | this.attr_("connectSeparatedPoints"))); | |
569 | ||
570 | // setup graphics context | |
571 | var prevX = NaN; | |
572 | var prevYs = [-1, -1]; | |
573 | var newYs; | |
574 | var yscale = axis.yscale; | |
575 | // should be same color as the lines but only 15% opaque. | |
576 | var rgb = new RGBColor(color); | |
577 | var err_color = | |
578 | 'rgba(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ',' + fillAlpha + ')'; | |
579 | ctx.fillStyle = err_color; | |
580 | ctx.beginPath(); | |
581 | while(iter.hasNext) { | |
582 | var point = iter.next(); | |
16febe6b DV |
583 | if (!Dygraph.isOK(point.y)) { |
584 | prevX = NaN; | |
585 | continue; | |
586 | } | |
587 | if (stackedGraph) { | |
588 | currBaseline = baseline[point.canvasx]; | |
589 | var lastY; | |
590 | if (currBaseline === undefined) { | |
591 | lastY = axisY; | |
592 | } else { | |
593 | if(stepPlot) { | |
594 | lastY = currBaseline[0]; | |
01a14b85 | 595 | } else { |
16febe6b | 596 | lastY = currBaseline; |
01a14b85 | 597 | } |
16febe6b DV |
598 | } |
599 | newYs = [ point.canvasy, lastY ]; | |
01a14b85 | 600 | |
16febe6b DV |
601 | if(stepPlot) { |
602 | // Step plots must keep track of the top and bottom of | |
603 | // the baseline at each point. | |
604 | if(prevYs[0] === -1) { | |
605 | baseline[point.canvasx] = [ point.canvasy, axisY ]; | |
01a14b85 | 606 | } else { |
16febe6b | 607 | baseline[point.canvasx] = [ point.canvasy, prevYs[0] ]; |
01a14b85 | 608 | } |
01a14b85 | 609 | } else { |
16febe6b | 610 | baseline[point.canvasx] = point.canvasy; |
01a14b85 | 611 | } |
01a14b85 | 612 | |
16febe6b DV |
613 | } else { |
614 | newYs = [ point.canvasy, axisY ]; | |
615 | } | |
616 | if (!isNaN(prevX)) { | |
617 | ctx.moveTo(prevX, prevYs[0]); | |
618 | ||
619 | if (stepPlot) { | |
620 | ctx.lineTo(point.canvasx, prevYs[0]); | |
621 | if(currBaseline) { | |
622 | // Draw to the bottom of the baseline | |
623 | ctx.lineTo(point.canvasx, currBaseline[1]); | |
01a14b85 | 624 | } else { |
01a14b85 DV |
625 | ctx.lineTo(point.canvasx, newYs[1]); |
626 | } | |
16febe6b DV |
627 | } else { |
628 | ctx.lineTo(point.canvasx, newYs[0]); | |
629 | ctx.lineTo(point.canvasx, newYs[1]); | |
01a14b85 | 630 | } |
16febe6b DV |
631 | |
632 | ctx.lineTo(prevX, prevYs[1]); | |
633 | ctx.closePath(); | |
01a14b85 | 634 | } |
16febe6b DV |
635 | prevYs = newYs; |
636 | prevX = point.canvasx; | |
01a14b85 DV |
637 | } |
638 | ctx.fill(); | |
639 | } | |
640 | }; |