// basic methods.
	ypSimpleScroll.prototype.scrollNorth = function() { this.startScroll(90) }
	ypSimpleScroll.prototype.scrollSouth = function() { this.startScroll(270)  }
	ypSimpleScroll.prototype.scrollWest  = function() { this.startScroll(180) }
	ypSimpleScroll.prototype.scrollEast  = function() { this.startScroll(0)   }
	
	
	// start scrolling in an arbitrary direction, with an optional arbitrary speed.
	// if no speed is provided, the default speed from the constructor parameter is used.
	ypSimpleScroll.prototype.startScroll = function(deg, speed) {
	  if (this.loaded)
	  {
		if (this.aniTimer) window.clearTimeout(this.aniTimer)
		this.overrideScrollAngle(deg)
	
		this.speed    = speed ? speed : this.origSpeed
		this.lastTime = (new Date()).getTime() - this.y.minRes
		this.aniTimer = window.setTimeout(this.gRef + ".scroll()", this.y.minRes)
	  }
	}
	
	// kills pending calls to .scroll(), resets speed
	ypSimpleScroll.prototype.endScroll = function() {
	  if (this.loaded)
	  {
		window.clearTimeout(this.aniTimer)
		this.aniTimer = 0;
		this.speed = this.origSpeed
	  }
	}

	// override the current angle from startScroll() with a new angle
	// this method should not be used with scrollTo() because it will
	// override the angle created by the first two params to scrollTo().
	ypSimpleScroll.prototype.overrideScrollAngle = function(deg) {
	  if (this.loaded)
	  {
		deg = deg % 360
		if (deg % 90 == 0) {
		  var cos = deg == 0  ? 1 : deg == 180 ? -1 : 0
		  var sin = deg == 90 ? -1 : deg == 270 ? 1 : 0
		} else {
		  var angle = deg * Math.PI / 180
		  var cos   = Math.cos(angle)
		  var sin   = Math.sin(angle)
		  sin = -sin
		}
		this.fx = cos / (Math.abs(cos) + Math.abs(sin))
		this.fy = sin / (Math.abs(cos) + Math.abs(sin))
		this.stopH = deg == 90 || deg == 270 ? this.scrollLeft : deg < 90 || deg > 270 ? this.scrollW : 0
		this.stopV = deg == 0 || deg == 180 ? this.scrollTop : deg < 180 ? 0 : this.scrollH
	  }
	}

	// override the speed for the current scroll.
	// should not be used with scrollTo, unless you want to 
	// override the speed computed from the aniLen param of scrollTo()
	ypSimpleScroll.prototype.overrideScrollSpeed = function(speed) {
	  if (this.loaded) this.speed = speed
	}

	// scroll to an arbitrary position in two dimensions over in
	// an arbitrary lenth of time.
	ypSimpleScroll.prototype.scrollTo = function(stopH, stopV, aniLen) {
	  if (this.loaded)
	  {
		if (stopH != this.scrollLeft || stopV != this.scrollTop) {
		  if (this.aniTimer) window.clearTimeout(this.aniTimer)
		  this.lastTime = (new Date()).getTime()
		  var dx = Math.abs(stopH - this.scrollLeft)
		  var dy = Math.abs(stopV - this.scrollTop)
		  var d = Math.sqrt(Math.pow(dx,2) + Math.pow(dy,2))
		  this.fx = (stopH - this.scrollLeft) / (dx + dy)
		  this.fy = (stopV - this.scrollTop) / (dx + dy)
		  this.stopH = stopH
		  this.stopV = stopV
		  this.speed = d / aniLen * 1000
		  window.setTimeout(this.gRef + ".scroll()", this.y.minRes)
		}
	  }
	}
	
	// jump to an arbitrary position in two dimensions.
	ypSimpleScroll.prototype.jumpTo = function(nx, ny) { 
	  if (this.loaded)
	  {
		nx = Math.min(Math.max(nx, 0), this.scrollW)
		ny = Math.min(Math.max(ny, 0), this.scrollH)
		this.scrollLeft = nx
		this.scrollTop = ny
		if (this.y.ns4)this.content.moveTo(-nx, -ny)
		else {
		  this.content.style.left = -nx + "px"
		  this.content.style.top = -ny + "px"
		}
	  }
	}

	ypSimpleScroll.minRes = 10
	ypSimpleScroll.ie  = document.all ? 1 : 0
	ypSimpleScroll.ns4 = document.layers ? 1 : 0
	ypSimpleScroll.dom = document.getElementById ? 1 : 0
	ypSimpleScroll.mac = navigator.platform == "MacPPC"
	ypSimpleScroll.mo5 = document.getElementById && !document.all ? 1 : 0

	// recursively calls itself to animate
	ypSimpleScroll.prototype.scroll = function() {
	  this.aniTimer = window.setTimeout(this.gRef + ".scroll()", this.y.minRes)
	  var nt = (new Date()).getTime()
	  var d = Math.round((nt - this.lastTime) / 1000 * this.speed)
	  if (d > 0)
	  {
		var nx = d * this.fx + this.scrollLeft
		var ny = d * this.fy + this.scrollTop
	
		var xOut = (nx >= this.scrollLeft && nx >= this.stopH) || (nx <= this.scrollLeft && nx <= this.stopH)
		var yOut = (ny >= this.scrollTop && ny >= this.stopV)  || (ny <= this.scrollTop && ny <= this.stopV)
		//window.status = nx + " " + this.fx + " " + this.scrollLeft + " " + this.stopH + " | " + ny + " " + this.fy + " " + this.scrollTop + " " + this.stopV + " : " + d
		if (nt - this.lastTime != 0 &&
		  ((this.fx == 0 && this.fy == 0) ||
		   (this.fy == 0 && xOut) ||
		   (this.fx == 0 && yOut) ||
		   (this.fx != 0 && this.fy != 0 && xOut && yOut)))
		{
		  this.jumpTo(this.stopH, this.stopV)
		  this.endScroll()
		 //  test.scrollWest();
		}
		else {
		  this.jumpTo(nx, ny)
		  this.lastTime = nt
		}
	  }
	}

	// constructor
	function ypSimpleScroll(id, left, top, width, height, speed, contentWidth, initLeft, initTop)
	{
	
	  var y = this.y = ypSimpleScroll
	  if (!initLeft)     initLeft     = 0
	  if (!initTop)      initTop      = 0
	  if (!contentWidth) contentWidth = width
	
	  // fix for netscape4 first-page bug.
	  if (document.layers && !y.ns4) history.go(0)
	
	  if (y.ie || y.ns4 || y.dom) {
		this.loaded    = false
		this.id      = id
		this.origSpeed  = speed
		this.aniTimer  = false
		this.op      = ""
		this.lastTime  = 0
		this.clipH    = height
		this.clipW    = width
		this.scrollTop  = initTop
		this.scrollLeft  = initLeft
		// global reference to this object
		this.gRef = "ypSimpleScroll_"+id
		eval(this.gRef+"=this")
	
		var d = document
		d.write('<style type="text/css">')
		d.write('#' + this.id + 'Container { position:relative; width:' + width + 'px; height:' + height + 'px; clip:rect(0 ' + width + ' ' + height + ' 0); overflow:hidden; }')
		d.write('#' + this.id + 'Container, #' + this.id + 'Content { position:relative; }')
		d.write('#' + this.id + 'Content { left:' + (-initLeft) + 'px; width:' + contentWidth + 'px; }')
		d.write('</style>')
	  }
	}
	
	// once the nceesary objects are present in the DOM, this gathers some info about them.
	ypSimpleScroll.prototype.load = function() {
	  var d, lyrId1, lyrId2
	
	  d = document
	  lyrId1 = this.id + "Container"
	  lyrId2 = this.id + "Content"
	  this.container  = this.y.dom ? d.getElementById(lyrId1) : this.y.ie ? d.all[lyrId1] : d.layers[lyrId1]
	  this.content  = obj2 = this.y.ns4 ? this.container.layers[lyrId2] : this.y.ie ? d.all[lyrId2] : d.getElementById(lyrId2)
	  this.docH    = Math.max(this.y.ns4 ? this.content.document.height : this.content.offsetHeight, this.clipH)
	  this.docW    = Math.max(this.y.ns4 ? this.content.document.width  : this.content.offsetWidth,  this.clipW)
	  this.scrollH  = this.docH - this.clipH
	  this.scrollW  = this.docW - this.clipW
	   this.loaded    = true
	  this.scrollLeft = Math.max(Math.min(this.scrollLeft, this.scrollW),0)
	   this.scrollTop  = Math.max(Math.min(this.scrollTop, this.scrollH),0)
	  this.jumpTo(this.scrollLeft, this.scrollTop)
	}
	

  // var test  = new ypSimpleScroll("myScroll", 10, 10, 20, 30, 100, 300)
  var test  = new ypSimpleScroll("myScroll", 0, 0, 20, 30, 150, 2500)
  
	//function ypSimpleScroll(id, left, top, width, height, speed, contentWidth, initLeft, initTop)
	//var test1  = new ypSimpleScroll("myScroll1", 0, 0, 310, 280, 150, 500)
	//var test2  = new ypSimpleScroll("myScroll2", 0, 0, 310, 280, 150, 500)
	//var test3  = new ypSimpleScroll("myScroll3", 0, 0, 310, 280, 150, 500)
	//var test4  = new ypSimpleScroll("myScroll4", 0, 0, 310, 180, 150, <?//=$src_wid?>)

		/*function ypSimpleScroll(id, left, top, width, height, speed, contentWidth, initLeft, initTop)
		var testYahoo  = new ypSimpleScroll("myScrollY", 0, 0, 320, 115, 150, 500);*/