analytics/webcontent/dojo16/dojox/charting/plot2d/Candlesticks.js

/*
	Copyright (c) 2004-2012, The Dojo Foundation All Rights Reserved.
	Available via Academic Free License >= 2.1 OR the modified BSD license.
	see: http://dojotoolkit.org/license for details
*/


if(!dojo._hasResource["dojox.charting.plot2d.Candlesticks"]){ //_hasResource checks added by build. Do not use _hasResource directly in your code.
dojo._hasResource["dojox.charting.plot2d.Candlesticks"] = true;
dojo.provide("dojox.charting.plot2d.Candlesticks");

dojo.require("dojox.charting.plot2d.common");
dojo.require("dojox.charting.plot2d.Base");

dojo.require("dojox.lang.utils");
dojo.require("dojox.lang.functional");
dojo.require("dojox.lang.functional.reversed");

(function(){
	var df = dojox.lang.functional, du = dojox.lang.utils,
		dc = dojox.charting.plot2d.common,
		purgeGroup = df.lambda("item.purgeGroup()");

	//	Candlesticks are based on the Bars plot type; we expect the following passed
	//	as values in a series:
	//	{ x?, open, close, high, low, mid? }
	//	if x is not provided, the array index is used.
	//	failing to provide the OHLC values will throw an error.
	dojo.declare("dojox.charting.plot2d.Candlesticks", dojox.charting.plot2d.Base, {
		//	summary:
		//		A plot that represents typical candlesticks (financial reporting, primarily).
		//		Unlike most charts, the Candlestick expects data points to be represented by
		//		an object of the form { x?, open, close, high, low, mid? }, where both
		//		x and mid are optional parameters.  If x is not provided, the index of the
		//		data array is used.
		defaultParams: {
			hAxis: "x",		// use a horizontal axis named "x"
			vAxis: "y",		// use a vertical axis named "y"
			gap:	2,		// gap between columns in pixels
			animate: null   // animate bars into place
		},
		optionalParams: {
			minBarSize:	1,	// minimal candle width in pixels
			maxBarSize:	1,	// maximal candle width in pixels
			// theme component
			stroke:		{},
			outline:	{},
			shadow:		{},
			fill:		{},
			font:		"",
			fontColor:	""
		},

		constructor: function(chart, kwArgs){
			//	summary:
			//		The constructor for a candlestick chart.
			//	chart: dojox.charting.Chart2D
			//		The chart this plot belongs to.
			//	kwArgs: dojox.charting.plot2d.__BarCtorArgs?
			//		An optional keyword arguments object to help define the plot.
			this.opt = dojo.clone(this.defaultParams);
			du.updateWithObject(this.opt, kwArgs);
			du.updateWithPattern(this.opt, kwArgs, this.optionalParams);
			this.series = [];
			this.hAxis = this.opt.hAxis;
			this.vAxis = this.opt.vAxis;
			this.animate = this.opt.animate;
		},

		collectStats: function(series){
			//	summary:
			//		Collect all statistics for drawing this chart.  Since the common
			//		functionality only assumes x and y, Candlesticks must create it's own
			//		stats (since data has no y value, but open/close/high/low instead).
			//	series: dojox.charting.Series[]
			//		The data series array to be drawn on this plot.
			//	returns: Object
			//		Returns an object in the form of { hmin, hmax, vmin, vmax }.

			//	we have to roll our own, since we need to use all four passed
			//	values to figure out our stats, and common only assumes x and y.
			var stats = dojo.delegate(dc.defaultStats);
			for(var i=0; i<series.length; i++){
				var run = series[i];
				if(!run.data.length){ continue; }
				var old_vmin = stats.vmin, old_vmax = stats.vmax;
				if(!("ymin" in run) || !("ymax" in run)){
					dojo.forEach(run.data, function(val, idx){
						if(val !== null){
							var x = val.x || idx + 1;
							stats.hmin = Math.min(stats.hmin, x);
							stats.hmax = Math.max(stats.hmax, x);
							stats.vmin = Math.min(stats.vmin, val.open, val.close, val.high, val.low);
							stats.vmax = Math.max(stats.vmax, val.open, val.close, val.high, val.low);
						}
					});
				}
				if("ymin" in run){ stats.vmin = Math.min(old_vmin, run.ymin); }
				if("ymax" in run){ stats.vmax = Math.max(old_vmax, run.ymax); }
			}
			return stats;	//	Object
		},

		getSeriesStats: function(){
			//	summary:
			//		Calculate the min/max on all attached series in both directions.
			//	returns: Object
			//		{hmin, hmax, vmin, vmax} min/max in both directions.
			var stats = this.collectStats(this.series);
			stats.hmin -= 0.5;
			stats.hmax += 0.5;
			return stats;
		},

		render: function(dim, offsets){
			//	summary:
			//		Run the calculations for any axes for this plot.
			//	dim: Object
			//		An object in the form of { width, height }
			//	offsets: Object
			//		An object of the form { l, r, t, b}.
			//	returns: dojox.charting.plot2d.Candlesticks
			//		A reference to this plot for functional chaining.
			if(this.zoom && !this.isDataDirty()){
				return this.performZoom(dim, offsets);
			}
			this.resetEvents();
			this.dirty = this.isDirty();
			if(this.dirty){
				dojo.forEach(this.series, purgeGroup);
				this._eventSeries = {};
				this.cleanGroup();
				var s = this.group;
				df.forEachRev(this.series, function(item){ item.cleanGroup(s); });
			}
			var t = this.chart.theme, f, gap, width,
				ht = this._hScaler.scaler.getTransformerFromModel(this._hScaler),
				vt = this._vScaler.scaler.getTransformerFromModel(this._vScaler),
				baseline = Math.max(0, this._vScaler.bounds.lower),
				baselineHeight = vt(baseline),
				events = this.events();
			f = dc.calculateBarSize(this._hScaler.bounds.scale, this.opt);
			gap = f.gap;
			width = f.size;
			for(var i = this.series.length - 1; i >= 0; --i){
				var run = this.series[i];
				if(!this.dirty && !run.dirty){
					t.skip();
					this._reconnectEvents(run.name);
					continue;
				}
				run.cleanGroup();
				var theme = t.next("candlestick", [this.opt, run]), s = run.group,
					eventSeries = new Array(run.data.length);
				for(var j = 0; j < run.data.length; ++j){
					var v = run.data[j];
					if(v !== null){
						var finalTheme = t.addMixin(theme, "candlestick", v, true);

						//	calculate the points we need for OHLC
						var x = ht(v.x || (j+0.5)) + offsets.l + gap,
							y = dim.height - offsets.b,
							open = vt(v.open),
							close = vt(v.close),
							high = vt(v.high),
							low = vt(v.low);
						if("mid" in v){
							var mid = vt(v.mid);
						}
						if(low > high){
							var tmp = high;
							high = low;
							low = tmp;
						}

						if(width >= 1){
							//	draw the line and rect, set up as a group and pass that to the events.
							var doFill = open > close;
							var line = { x1: width/2, x2: width/2, y1: y - high, y2: y - low },
								rect = {
									x: 0, y: y-Math.max(open, close),
									width: width, height: Math.max(doFill ? open-close : close-open, 1)
								};
							shape = s.createGroup();
							shape.setTransform({dx: x, dy: 0 });
							var inner = shape.createGroup();
							inner.createLine(line).setStroke(finalTheme.series.stroke);
							inner.createRect(rect).setStroke(finalTheme.series.stroke).
								setFill(doFill ? finalTheme.series.fill : "white");
							if("mid" in v){
								//	add the mid line.
								inner.createLine({
									x1: (finalTheme.series.stroke.width||1), x2: width - (finalTheme.series.stroke.width || 1),
									y1: y - mid, y2: y - mid
								}).setStroke(doFill ? "white" : finalTheme.series.stroke);
							}

							//	TODO: double check this.
							run.dyn.fill   = finalTheme.series.fill;
							run.dyn.stroke = finalTheme.series.stroke;
							if(events){
								var o = {
									element: "candlestick",
									index:   j,
									run:     run,
									shape:   inner,
									x:       x,
									y:       y-Math.max(open, close),
									cx:		 width/2,
									cy:		 (y-Math.max(open, close)) + (Math.max(doFill ? open-close : close-open, 1)/2),
									width:	 width,
									height:  Math.max(doFill ? open-close : close-open, 1),
									data:	 v
								};
								this._connectEvents(o);
								eventSeries[j] = o;
							}
						}
						if(this.animate){
							this._animateCandlesticks(shape, y - low, high - low);
						}
					}
				}
				this._eventSeries[run.name] = eventSeries;
				run.dirty = false;
			}
			this.dirty = false;
			return this;	//	dojox.charting.plot2d.Candlesticks
		},
		_animateCandlesticks: function(shape, voffset, vsize){
			dojox.gfx.fx.animateTransform(dojo.delegate({
				shape: shape,
				duration: 1200,
				transform: [
					{name: "translate", start: [0, voffset - (voffset/vsize)], end: [0, 0]},
					{name: "scale", start: [1, 1/vsize], end: [1, 1]},
					{name: "original"}
				]
			}, this.animate)).play();
		}
	});
})();

}