/*
ASCII Plasma (c) 2006 by Lee W. Fastenau
Feel free to use and/or modify this code as long as you don't make money from it.
This attribution must stay.  Stay, it must.  Yes.
*/
Plasma = function (elem,width,height) {
	this.elem = elem;
	this.width = width;
	this.height = height;
	
	this.row = 0;
	this.timeShift = 0;
	this.renderString = '';
	
	this.functions = [
		function (x,y,t) {
			return (Math.sin(x*.15-new Date()*.008))+1;
		},
		function (x,y,t) {
			return (Math.sin((y-10)*.3*(t-2)+new Date()*.008))+1;
		},
		function (x,y,t) {
			return (Math.sin(Math.sqrt(Math.pow(x/2-10,2)+Math.pow(y-10,2))*(0.4)))+1;
		}
	];
	var theThis = this;
	this.intervalId = setInterval (function(){theThis.draw()},1);
}

Plasma.prototype.draw = function () {
		this.timeShift = new Date();
		this.renderString = '\r\n';

	for (var y=0;y<this.height;y++) {
		for (var x=0;x<this.width;x++) {
			this.renderString += Plasma.palette.charAt(Math.round(this.calcValueFaster(x,y,this.timeShift)*(Plasma.maxPaletteIndex)));
		}
		this.renderString += '\r\n';
	}
	//outStr += ' ';
	this.elem.firstChild.nodeValue = this.renderString;
}

Plasma.prototype.calcValue = function (x,y,t) {
	var retVal = 0;
	var numFunctions = this.functions.length;
	for (var i=0;i<numFunctions;i++) {
		retVal += this.functions[i](x,y,t);
	}
	return retVal/(numFunctions*2);
}

Plasma.prototype.calcValueFaster = function (x,y,t) {
	var retVal = (Math.sin(x*.15-t*.008));
	retVal += (Math.sin((y-10)*.3*(Math.sin(t/700)-2)+new Date()*.008));
	retVal += (Math.sin(Math.sqrt(Math.pow(x/2-10,2)+Math.pow(y-10,2))*(0.4)));
	retVal = retVal / 6 + 0.5;
	return retVal;
}

Plasma.palette = ' `.!:/;([icILYOPXBMBXPOYLIci[(;/:!.`';
Plasma.palette = ' `.!:/;([icILYOPXBMBXPOYLIci[(;/:!.` .:;[cLOXMPLi;!           ';
Plasma.maxPaletteIndex = Plasma.palette.length-1;