/* This script and many more are available free online at
  The JavaScript Source!! http://javascript.internet.com
  Created by: Timothy Groves | http://www.brandspankingnew.net/ */
  var useBSNns;
  
  if (useBSNns) {
           if (typeof(bsn) == "undefined")
                    bsn = {}
             var _bsn = bsn;
  } else {
            var _bsn = this;
  }
  
  _bsn.Crossfader = function (divs, fadetime, delay ) {        
           this.nAct = -1;
           this.aDivs = divs;
          
           for (var i=0;i<divs.length;i++) {
             document.getElementById(divs[i]).style.opacity = 0;
             document.getElementById(divs[i]).style.position = "absolute";
             document.getElementById(divs[i]).style.filter = "alpha(opacity=0)";
             document.getElementById(divs[i]).style.visibility = "hidden";
           }
          
           this.nDur = fadetime;
    this.nDelay = delay;
    this._newfade();
  }
  
  _bsn.Crossfader.prototype._newfade = function() {
    if (this.nID1)
      clearInterval(this.nID1);
             this.nOldAct = this.nAct;
      this.nAct++;
  
           if (!this.aDivs[this.nAct])        this.nAct = 0;
  
           if (this.nAct == this.nOldAct)
      return false;
  
    document.getElementById( this.aDivs[this.nAct] ).style.visibility = "visible";
    this.nInt = 50;
    this.nTime = 0;
    var p=this;
    this.nID2 = setInterval(function() { p._fade() }, this.nInt);
  }
  
  _bsn.Crossfader.prototype._fade = function() {
    this.nTime += this.nInt;
           var ieop = Math.round( this._easeInOut(this.nTime, 0, 1, this.nDur) * 100 );
           var op = ieop / 100;
           document.getElementById( this.aDivs[this.nAct] ).style.opacity = op;
           document.getElementById( this.aDivs[this.nAct] ).style.filter = "alpha(opacity="+ieop+")";
  
    if (this.nOldAct > -1) {
      document.getElementById( this.aDivs[this.nOldAct] ).style.opacity = 1 - op;
                    document.getElementById( this.aDivs[this.nOldAct] ).style.filter = "alpha(opacity="+(100 - ieop)+")";
           }
          
           if (this.nTime == this.nDur) {
                    clearInterval( this.nID2 );
                  
    if (this.nOldAct > -1)
             document.getElementById( this.aDivs[this.nOldAct] ).style.visibility = "hidden";        
      var p=this;
      this.nID1 = setInterval(function() { p._newfade() }, this.nDelay);
    }
  }
  
  _bsn.Crossfader.prototype._easeInOut = function(t,b,c,d) {
    return c/2 * (1 - Math.cos(Math.PI*t/d)) + b;
  }