| 1 | /* |
| 2 | PlotKit Canvas |
| 3 | ============== |
| 4 | |
| 5 | Provides HTML Canvas Renderer. This is supported under: |
| 6 | |
| 7 | - Safari 2.0 |
| 8 | - Mozilla Firefox 1.5 |
| 9 | - Opera 9.0 preview 2 |
| 10 | - IE 6 (via VML Emulation) |
| 11 | |
| 12 | It uses DIVs for labels. |
| 13 | |
| 14 | Copyright |
| 15 | --------- |
| 16 | Copyright 2005,2006 (c) Alastair Tse <alastair^liquidx.net> |
| 17 | For use under the BSD license. <http://www.liquidx.net/plotkit> |
| 18 | |
| 19 | */ |
| 20 | // -------------------------------------------------------------------- |
| 21 | // Check required components |
| 22 | // -------------------------------------------------------------------- |
| 23 | |
| 24 | try { |
| 25 | if ((typeof(PlotKit.Base) == 'undefined') || |
| 26 | (typeof(PlotKit.Layout) == 'undefined')) |
| 27 | { |
| 28 | throw ""; |
| 29 | } |
| 30 | } |
| 31 | catch (e) { |
| 32 | throw "PlotKit.Layout depends on MochiKit.{Base,Color,DOM,Format} and PlotKit.{Base,Layout}" |
| 33 | } |
| 34 | |
| 35 | |
| 36 | // ------------------------------------------------------------------------ |
| 37 | // Defines the renderer class |
| 38 | // ------------------------------------------------------------------------ |
| 39 | |
| 40 | if (typeof(PlotKit.CanvasRenderer) == 'undefined') { |
| 41 | PlotKit.CanvasRenderer = {}; |
| 42 | } |
| 43 | |
| 44 | PlotKit.CanvasRenderer.NAME = "PlotKit.CanvasRenderer"; |
| 45 | PlotKit.CanvasRenderer.VERSION = PlotKit.VERSION; |
| 46 | |
| 47 | PlotKit.CanvasRenderer.__repr__ = function() { |
| 48 | return "[" + this.NAME + " " + this.VERSION + "]"; |
| 49 | }; |
| 50 | |
| 51 | PlotKit.CanvasRenderer.toString = function() { |
| 52 | return this.__repr__(); |
| 53 | } |
| 54 | |
| 55 | PlotKit.CanvasRenderer = function(element, layout, options) { |
| 56 | if (arguments.length > 0) |
| 57 | this.__init__(element, layout, options); |
| 58 | }; |
| 59 | |
| 60 | PlotKit.CanvasRenderer.prototype.__init__ = function(element, layout, options) { |
| 61 | var isNil = MochiKit.Base.isUndefinedOrNull; |
| 62 | var Color = MochiKit.Color.Color; |
| 63 | |
| 64 | // default options |
| 65 | this.options = { |
| 66 | "drawBackground": true, |
| 67 | "backgroundColor": Color.whiteColor(), |
| 68 | "colorScheme": PlotKit.Base.palette(PlotKit.Base.baseColors()[0]), |
| 69 | "strokeColor": Color.whiteColor(), |
| 70 | "strokeColorTransform": "asStrokeColor", |
| 71 | "strokeWidth": 0.5, |
| 72 | "shouldFill": true, |
| 73 | "shouldStroke": true, |
| 74 | "drawXAxis": true, |
| 75 | "drawYAxis": true, |
| 76 | "axisLineColor": Color.blackColor(), |
| 77 | "axisLineWidth": 0.5, |
| 78 | "axisTickSize": 3, |
| 79 | "axisLabelColor": Color.blackColor(), |
| 80 | "axisLabelFont": "Arial", |
| 81 | "axisLabelFontSize": 9, |
| 82 | "axisLabelWidth": 50, |
| 83 | "pieRadius": 0.4, |
| 84 | "enableEvents": true |
| 85 | }; |
| 86 | MochiKit.Base.update(this.options, options ? options : {}); |
| 87 | |
| 88 | this.layout = layout; |
| 89 | this.element = MochiKit.DOM.getElement(element); |
| 90 | this.container = this.element.parentNode; |
| 91 | |
| 92 | // Stuff relating to Canvas on IE support |
| 93 | this.isIE = PlotKit.Base.excanvasSupported(); |
| 94 | |
| 95 | if (this.isIE && !isNil(G_vmlCanvasManager)) { |
| 96 | this.IEDelay = 0.5; |
| 97 | this.maxTries = 5; |
| 98 | this.renderDelay = null; |
| 99 | this.clearDelay = null; |
| 100 | this.element = G_vmlCanvasManager.initElement(this.element); |
| 101 | } |
| 102 | |
| 103 | this.height = this.element.height; |
| 104 | this.width = this.element.width; |
| 105 | |
| 106 | // --- check whether everything is ok before we return |
| 107 | |
| 108 | if (isNil(this.element)) |
| 109 | throw "CanvasRenderer() - passed canvas is not found"; |
| 110 | |
| 111 | if (!this.isIE && !(PlotKit.CanvasRenderer.isSupported(this.element))) |
| 112 | throw "CanvasRenderer() - Canvas is not supported."; |
| 113 | |
| 114 | if (isNil(this.container) || (this.container.nodeName.toLowerCase() != "div")) |
| 115 | throw "CanvasRenderer() - <canvas> needs to be enclosed in <div>"; |
| 116 | |
| 117 | // internal state |
| 118 | this.xlabels = new Array(); |
| 119 | this.ylabels = new Array(); |
| 120 | this.isFirstRender = true; |
| 121 | |
| 122 | this.area = { |
| 123 | x: this.options.yAxisLabelWidth + 2 * this.options.axisTickSize, |
| 124 | y: 0 |
| 125 | }; |
| 126 | this.area.w = this.width - this.area.x - this.options.rightGap; |
| 127 | this.area.h = this.height - this.options.axisLabelFontSize - |
| 128 | 2 * this.options.axisTickSize; |
| 129 | |
| 130 | MochiKit.DOM.updateNodeAttributes(this.container, |
| 131 | {"style":{ "position": "relative", "width": this.width + "px"}}); |
| 132 | }; |
| 133 | |
| 134 | |
| 135 | PlotKit.CanvasRenderer.prototype._renderLineAxis = function() { |
| 136 | this._renderAxis(); |
| 137 | }; |
| 138 | |
| 139 | |
| 140 | PlotKit.CanvasRenderer.prototype._renderAxis = function() { |
| 141 | if (!this.options.drawXAxis && !this.options.drawYAxis) |
| 142 | return; |
| 143 | |
| 144 | var context = this.element.getContext("2d"); |
| 145 | |
| 146 | var labelStyle = {"style": |
| 147 | {"position": "absolute", |
| 148 | "fontSize": this.options.axisLabelFontSize + "px", |
| 149 | "zIndex": 10, |
| 150 | "color": this.options.axisLabelColor.toRGBString(), |
| 151 | "width": this.options.axisLabelWidth + "px", |
| 152 | "overflow": "hidden" |
| 153 | } |
| 154 | }; |
| 155 | |
| 156 | // axis lines |
| 157 | context.save(); |
| 158 | context.strokeStyle = this.options.axisLineColor.toRGBString(); |
| 159 | context.lineWidth = this.options.axisLineWidth; |
| 160 | |
| 161 | |
| 162 | if (this.options.drawYAxis) { |
| 163 | if (this.layout.yticks) { |
| 164 | var drawTick = function(tick) { |
| 165 | if (typeof(tick) == "function") return; |
| 166 | var x = this.area.x; |
| 167 | var y = this.area.y + tick[0] * this.area.h; |
| 168 | context.beginPath(); |
| 169 | context.moveTo(x, y); |
| 170 | context.lineTo(x - this.options.axisTickSize, y); |
| 171 | context.closePath(); |
| 172 | context.stroke(); |
| 173 | |
| 174 | var label = DIV(labelStyle, tick[1]); |
| 175 | var top = (y - this.options.axisLabelFontSize / 2); |
| 176 | if (top < 0) top = 0; |
| 177 | |
| 178 | if (top + this.options.axisLabelFontSize + 3 > this.height) { |
| 179 | label.style.bottom = "0px"; |
| 180 | } else { |
| 181 | label.style.top = top + "px"; |
| 182 | } |
| 183 | label.style.left = "0px"; |
| 184 | label.style.textAlign = "right"; |
| 185 | label.style.width = this.options.yAxisLabelWidth + "px"; |
| 186 | MochiKit.DOM.appendChildNodes(this.container, label); |
| 187 | this.ylabels.push(label); |
| 188 | }; |
| 189 | |
| 190 | MochiKit.Iter.forEach(this.layout.yticks, bind(drawTick, this)); |
| 191 | |
| 192 | // The lowest tick on the y-axis often overlaps with the leftmost |
| 193 | // tick on the x-axis. Shift the bottom tick up a little bit to |
| 194 | // compensate if necessary. |
| 195 | var bottomTick = this.ylabels[0]; |
| 196 | var fontSize = this.options.axisLabelFontSize; |
| 197 | var bottom = parseInt(bottomTick.style.top) + fontSize; |
| 198 | if (bottom > this.height - fontSize) { |
| 199 | bottomTick.style.top = (parseInt(bottomTick.style.top) - |
| 200 | fontSize / 2) + "px"; |
| 201 | } |
| 202 | } |
| 203 | |
| 204 | context.beginPath(); |
| 205 | context.moveTo(this.area.x, this.area.y); |
| 206 | context.lineTo(this.area.x, this.area.y + this.area.h); |
| 207 | context.closePath(); |
| 208 | context.stroke(); |
| 209 | } |
| 210 | |
| 211 | if (this.options.drawXAxis) { |
| 212 | if (this.layout.xticks) { |
| 213 | var drawTick = function(tick) { |
| 214 | if (typeof(dataset) == "function") return; |
| 215 | |
| 216 | var x = this.area.x + tick[0] * this.area.w; |
| 217 | var y = this.area.y + this.area.h; |
| 218 | context.beginPath(); |
| 219 | context.moveTo(x, y); |
| 220 | context.lineTo(x, y + this.options.axisTickSize); |
| 221 | context.closePath(); |
| 222 | context.stroke(); |
| 223 | |
| 224 | var label = DIV(labelStyle, tick[1]); |
| 225 | label.style.textAlign = "center"; |
| 226 | label.style.bottom = "0px"; |
| 227 | |
| 228 | var left = (x - this.options.axisLabelWidth/2); |
| 229 | if (left + this.options.axisLabelWidth > this.width) { |
| 230 | left = this.width - this.options.xAxisLabelWidth; |
| 231 | label.style.textAlign = "right"; |
| 232 | } |
| 233 | if (left < 0) { |
| 234 | left = 0; |
| 235 | label.style.textAlign = "left"; |
| 236 | } |
| 237 | |
| 238 | label.style.left = left + "px"; |
| 239 | label.style.width = this.options.xAxisLabelWidth + "px"; |
| 240 | MochiKit.DOM.appendChildNodes(this.container, label); |
| 241 | this.xlabels.push(label); |
| 242 | }; |
| 243 | |
| 244 | MochiKit.Iter.forEach(this.layout.xticks, bind(drawTick, this)); |
| 245 | } |
| 246 | |
| 247 | context.beginPath(); |
| 248 | context.moveTo(this.area.x, this.area.y + this.area.h); |
| 249 | context.lineTo(this.area.x + this.area.w, this.area.y + this.area.h); |
| 250 | context.closePath(); |
| 251 | context.stroke(); |
| 252 | } |
| 253 | |
| 254 | context.restore(); |
| 255 | |
| 256 | }; |
| 257 | |
| 258 | PlotKit.CanvasRenderer.prototype.clear = function() { |
| 259 | if (this.isIE) { |
| 260 | // VML takes a while to start up, so we just poll every this.IEDelay |
| 261 | try { |
| 262 | if (this.clearDelay) { |
| 263 | this.clearDelay.cancel(); |
| 264 | this.clearDelay = null; |
| 265 | } |
| 266 | var context = this.element.getContext("2d"); |
| 267 | } |
| 268 | catch (e) { |
| 269 | this.isFirstRender = false; |
| 270 | this.clearDelay = MochiKit.Async.wait(this.IEDelay); |
| 271 | this.clearDelay.addCallback(bind(this.clear, this)); |
| 272 | return; |
| 273 | } |
| 274 | } |
| 275 | |
| 276 | var context = this.element.getContext("2d"); |
| 277 | context.clearRect(0, 0, this.width, this.height); |
| 278 | |
| 279 | MochiKit.Iter.forEach(this.xlabels, MochiKit.DOM.removeElement); |
| 280 | MochiKit.Iter.forEach(this.ylabels, MochiKit.DOM.removeElement); |
| 281 | this.xlabels = new Array(); |
| 282 | this.ylabels = new Array(); |
| 283 | }; |
| 284 | |
| 285 | // ---------------------------------------------------------------- |
| 286 | // Everything below here is experimental and undocumented. |
| 287 | // ---------------------------------------------------------------- |
| 288 | |
| 289 | |
| 290 | PlotKit.CanvasRenderer.isSupported = function(canvasName) { |
| 291 | var canvas = null; |
| 292 | try { |
| 293 | if (MochiKit.Base.isUndefinedOrNull(canvasName)) |
| 294 | canvas = MochiKit.DOM.CANVAS({}); |
| 295 | else |
| 296 | canvas = MochiKit.DOM.getElement(canvasName); |
| 297 | var context = canvas.getContext("2d"); |
| 298 | } |
| 299 | catch (e) { |
| 300 | var ie = navigator.appVersion.match(/MSIE (\d\.\d)/); |
| 301 | var opera = (navigator.userAgent.toLowerCase().indexOf("opera") != -1); |
| 302 | if ((!ie) || (ie[1] < 6) || (opera)) |
| 303 | return false; |
| 304 | return true; |
| 305 | } |
| 306 | return true; |
| 307 | }; |
| 308 | |
| 309 | // Namespace Iniitialisation |
| 310 | |
| 311 | PlotKit.Canvas = {} |
| 312 | PlotKit.Canvas.CanvasRenderer = PlotKit.CanvasRenderer; |
| 313 | |
| 314 | PlotKit.Canvas.EXPORT = [ |
| 315 | "CanvasRenderer" |
| 316 | ]; |
| 317 | |
| 318 | PlotKit.Canvas.EXPORT_OK = [ |
| 319 | "CanvasRenderer" |
| 320 | ]; |
| 321 | |
| 322 | PlotKit.Canvas.__new__ = function() { |
| 323 | var m = MochiKit.Base; |
| 324 | |
| 325 | m.nameFunctions(this); |
| 326 | |
| 327 | this.EXPORT_TAGS = { |
| 328 | ":common": this.EXPORT, |
| 329 | ":all": m.concat(this.EXPORT, this.EXPORT_OK) |
| 330 | }; |
| 331 | }; |
| 332 | |
| 333 | PlotKit.Canvas.__new__(); |
| 334 | MochiKit.Base._exportSymbols(this, PlotKit.Canvas); |
| 335 | |