Add initial candles adapter.

js/adapters/flotr/candles.js

@@ -0,0 +1,142 @@
+Flotr.addType( 'candles', {
+	options: {
+		show: false,           // => setting to true will show candle sticks, false will hide
+		lineWidth: 1,          // => in pixels
+		wickLineWidth: 1,      // => in pixels
+		candleWidth: 0.6,      // => in units of the x axis
+		fill: true,            // => true to fill the area from the line to the x axis, false for (transparent) no fill
+		upFillColor: '#00A8F0',// => up sticks fill color
+		downFillColor: '#CB4B4B',// => down sticks fill color
+		fillOpacity: 0.5,      // => opacity of the fill color, set to 1 for a solid fill, 0 hides the fill
+		// TODO Test this barcharts option.
+		barcharts: false       // => draw as barcharts (not standard bars but financial barcharts)
+	},
+
+	draw : function (options) {
+		var context = options.context;
+
+		context.save();
+		context.lineJoin = 'miter';
+		context.lineCap = 'butt';
+		// @TODO linewidth not interpreted the right way.
+		context.lineWidth = options.wickLineWidth || options.lineWidth;
+
+		this.plot(options);
+
+		context.restore();
+	},
+
+	plot : function (options) {
+		var
+			data          = options.data,
+			context       = options.context,
+			xScale        = options.xScale,
+			yScale        = options.yScale,
+			width         = options.candleWidth / 2,
+			shadowSize    = options.shadowSize,
+			lineWidth     = options.lineWidth,
+			wickLineWidth = options.wickLineWidth,
+			pixelOffset   = (wickLineWidth % 2) / 2,
+			color,
+			x, y,
+			open, high, low, close,
+			left, right, bottom, top, bottom2, top2,
+			i;
+
+		if (data.length < 1) return;
+
+		for (i = 0; i < data.length; i++) {
+			x = data[i][0];
+
+			var candleIndex = data[i][0];
+			var qb = options.quotes[candleIndex]; // Note : this assumes the candles are stored in options.quotes as JSON objects.
+			open    = qb.o;
+			high    = qb.h;
+			low     = qb.l;
+			close   = qb.c;
+			left    = xScale(x - width);
+			right   = xScale(x + width);
+			bottom  = yScale(low);
+			top     = yScale(high);
+			bottom2 = yScale(Math.min(open, close));
+			top2    = yScale(Math.max(open, close));
+
+			/*
+			// TODO skipping
+			if(right < xa.min || left > xa.max || top < ya.min || bottom > ya.max)
+				continue;
+			 */
+
+			color = options[open > close ? 'downFillColor' : 'upFillColor'];
+
+			// Fill the candle.
+			// TODO Test the barcharts option
+			if (options.fill && !options.barcharts) {
+				context.fillStyle = 'rgba(0,0,0,0.05)';
+				context.fillRect(left + shadowSize, top2 + shadowSize, right - left, bottom2 - top2);
+				context.save();
+				context.globalAlpha = options.fillOpacity;
+				context.fillStyle = color;
+				context.fillRect(left, top2 + lineWidth, right - left, bottom2 - top2);
+				context.restore();
+			}
+
+			// Draw candle outline/border, high, low.
+			if (lineWidth || wickLineWidth) {
+				x = Math.floor((left + right) / 2) + pixelOffset;
+
+				context.strokeStyle = color;
+				context.beginPath();
+
+				// TODO Again with the bartcharts
+				if (options.barcharts) {
+
+				context.moveTo(x, Math.floor(top + width));
+				context.lineTo(x, Math.floor(bottom + width));
+
+				y = Math.floor(open + width) + 0.5;
+				context.moveTo(Math.floor(left) + pixelOffset, y);
+				context.lineTo(x, y);
+
+				y = Math.floor(close + width) + 0.5;
+				context.moveTo(Math.floor(right) + pixelOffset, y);
+				context.lineTo(x, y);
+				} else {
+				context.strokeRect(left, top2 + lineWidth, right - left, bottom2 - top2);
+
+				context.moveTo(x, Math.floor(top2 + lineWidth));
+				context.lineTo(x, Math.floor(top + lineWidth));
+				context.moveTo(x, Math.floor(bottom2 + lineWidth));
+				context.lineTo(x, Math.floor(bottom + lineWidth));
+				}
+
+				context.closePath();
+				context.stroke();
+			}
+		}
+	},
+
+	extendXRange: function (axis, data, options) {
+		axis.max = Math.max( axis.datamax , axis.max ) + options.candleWidth / 2;
+		axis.min = Math.min( axis.datamin, axis.min ) - options.candleWidth / 2;
+	},
+
+	extendYRange: function (axis, data, options) {
+		var maxHigh = null, minLow = null;
+
+		for (i = 0; i < data.length; i++) {
+			var candleIndex = data[i][0];
+			var qb = options.quotes[candleIndex]; // Note : this assumes the candles are stored in options.quotes as JSON objects.
+
+			if( maxHigh === null || maxHigh < qb.h )
+				maxHigh = qb.h;
+			if( minLow === null || minLow < qb.l )
+				minLow = qb.l;
+		}
+
+		if( maxHigh != null && minLow != null ){
+			axis.max = Math.max( maxHigh, axis.max );
+			axis.min = Math.min( minLow, axis.min );
+		}
+	}
+} );