From 9479b214fab5e2a0576c737d2527fca886b03d9c Mon Sep 17 00:00:00 2001
From: Francisco Dans <fdansv@gmail.com>
Date: Wed, 25 Feb 2015 12:42:21 +0100
Subject: [PATCH] initialises layers JIT, instead of in the constructor

---
 lib/torque/renderer/ball.js | 33 ++++++++++++++++++---------------
 1 file changed, 18 insertions(+), 15 deletions(-)

diff --git a/lib/torque/renderer/ball.js b/lib/torque/renderer/ball.js
index c244534..8c6d739 100644
--- a/lib/torque/renderer/ball.js
+++ b/lib/torque/renderer/ball.js
@@ -10,8 +10,7 @@ function BallRenderer(thecanvas){
 	this.width = this.canvas.width;
 	this.height = this.canvas.height;
 	this.size = this.width * this.height;
-	this.pointList = new Uint8ClampedArray(this.size * 4);
-	this.contourLayer = new Uint8ClampedArray(this.size * 4);
+	this.pointLayer = new Uint8ClampedArray(this.size * 4);
 	this.radius = 30;
 	this.drawnTemp = [];
 	this.prof = 0;
@@ -72,24 +71,28 @@ BallRenderer.prototype = {
 		}
 		a[a.length-1] = 255;
 		var l = -step/2;
+		var gradient = new Uint8ClampedArray(1024);
 		for(var i = 0; i<a.length; i++){
-			var thisAlpha = a[i]/255;
-			this.ctx.fillStyle = "rgba(0, 0, 0, " + thisAlpha + ")";
-			this.ctx.fillRect(0, l, 1, step);
-			l+=step;
+			var y = Math.round(i*step);
+			var thisAlpha = a[i];
+			while(y<step*(i+1)){
+				gradient[y*4+3] = thisAlpha;
+				y++;
+			}
 		}
-		var _grad = this.ctx.getImageData(0, 0, 1, 255).data;
-		this.ctx.clearRect(0, 0, 1, 256);
-		
-		for (var i = 0; i< this.pointList.length; i+=4){
-			if(this.pointList[i+3] === 0) continue;
-			var currentAlpha = this.pointList[i+3];
-			this.contourLayer[i+3] = this.pointList[i+3] === 255? 255: _grad[currentAlpha*4+3];
+		if(!this.contourLayer) this.contourLayer = new Uint8ClampedArray(this.size * 4);
+		for (var i = 0; i< this.pointLayer.length; i+=4){
+			if(this.pointLayer[i+3] === 0) continue;
+			var currentAlpha = this.pointLayer[i+3];
+			this.contourLayer[i+3] = gradient[currentAlpha*4+3];
 		}
 	},
 	draw: function(dataArray){
-		if(!dataArray) dataArray = this.pointList;
-		else this.contourLayer = dataArray;
+		if (!dataArray){
+			if (this.isoplethLayer) dataArray = this.isoplethLayer;
+			else if (this.contourLayer) dataArray = this.contourLayer;
+			else dataArray = this.pointLayer;
+		}
 		if(!this.imageData) this.imageData = this.ctx.createImageData(this.width, this.height);
 	    this.imageData.data.set(dataArray);
 	    this.ctx.putImageData(this.imageData, 0, 0);