ns4=(document.layers)?true:false

var displayImgAmount=4	//视区窗口可显示个数
var divWidth=180	//每块图片占位宽
var divHeight=90	//每块图片占位高

var startDnum=0
var nextDnum=startDnum+displayImgAmount
var timeID
var outHover=false

var startDivClipLeft
var nextDivClipRight

function initDivPlace(){
	if (ns4){
		for (i=0;i<displayImgAmount;i++){
			eval("document.divOuter.document.divAds"+i+".left="+divWidth*i)
		}
		for (i=displayImgAmount;i<imgArr.length;i++){
			eval("document.divOuter.document.divAds"+i+".left="+divWidth*displayImgAmount)
		}
	}else{
		for (i=0;i<displayImgAmount;i++){
			eval("document.all.divAds"+i+".style.left="+divWidth*i)
		}
		for (i=displayImgAmount;i<imgArr.length;i++){
			eval("document.all.divAds"+i+".style.left="+divWidth*displayImgAmount)
		}
	}
}

function mvStart(){
	timeID=setTimeout(moveLeftDiv,moveRelax)
}

function mvStop(){
	clearTimeout(timeID)
}

function moveLeftDiv(){
	if (ns4){
		for (i=0;i<=displayImgAmount;i++){
			eval("document.divOuter.document.divAds"+parseInt((startDnum+i)%imgArr.length)+".left=document.divOuter.document.divAds"+parseInt((startDnum+i)%imgArr.length)+".left-moveStep")
		}

		startDivClipLeft=parseInt(eval("document.divOuter.document.divAds"+startDnum+".clip.left"))
		nextDivClipRight=parseInt(eval("document.divOuter.document.divAds"+nextDnum+".clip.right"))

		if (startDivClipLeft+moveStep>divWidth){
			eval("document.divOuter.document.divAds"+nextDnum+".clip.right="+divWidth)
			
			eval("document.divOuter.document.divAds"+startDnum+".left="+divWidth*displayImgAmount)
			eval("document.divOuter.document.divAds"+parseInt((nextDnum+1)%imgArr.length)+".left=document.divOuter.document.divAds"+nextDnum+".left+"+divWidth)
			eval("document.divOuter.document.divAds"+parseInt((nextDnum+1)%imgArr.length)+".clip.left=0")
			
			
			startDnum=(++startDnum)%imgArr.length
			nextDnum=(startDnum+displayImgAmount)%imgArr.length
			
			startDivClipLeft=moveStep-(divWidth-startDivClipLeft)
			nextDivClipRight=moveStep-(divWidth-nextDivClipRight)
		}else{
			eval("document.divOuter.document.divAds"+nextDnum+".clip.left=0")
			startDivClipLeft+=moveStep
			nextDivClipRight+=moveStep
		}
		eval("document.divOuter.document.divAds"+startDnum+".clip.left="+startDivClipLeft)
		eval("document.divOuter.document.divAds"+nextDnum+".clip.right="+nextDivClipRight)
	}else{
		for (i=0;i<=displayImgAmount;i++){
			eval("document.all.divAds"+parseInt((startDnum+i)%imgArr.length)+".style.left=document.all.divAds"+parseInt((startDnum+i)%imgArr.length)+".style.pixelLeft-moveStep")
		}
	
		startDivClipLeft=parseInt(eval("document.all.divAds"+startDnum+".currentStyle.clipLeft"))
		nextDivClipRight=parseInt(eval("document.all.divAds"+nextDnum+".currentStyle.clipRight"))
	
		if (startDivClipLeft+moveStep>divWidth){
			eval("document.all.divAds"+nextDnum+".style.clip='rect(0,"+divWidth+","+divHeight+",0"+")'")
			
			eval("document.all.divAds"+startDnum+".style.left="+divWidth*displayImgAmount)
			eval("document.all.divAds"+parseInt((nextDnum+1)%imgArr.length)+".style.left=document.all.divAds"+nextDnum+".style.pixelLeft+"+divWidth)
			
			startDnum=(++startDnum)%imgArr.length
			nextDnum=(startDnum+displayImgAmount)%imgArr.length
			
			startDivClipLeft=moveStep-(divWidth-startDivClipLeft)
			nextDivClipRight=moveStep-(divWidth-nextDivClipRight)
		}else{
			startDivClipLeft+=moveStep
			nextDivClipRight+=moveStep
		}
		eval("document.all.divAds"+startDnum+".style.clip='rect(0,"+divWidth+","+divHeight+","+startDivClipLeft+")'")
		eval("document.all.divAds"+nextDnum+".style.clip='rect(0,"+nextDivClipRight+","+divHeight+",0)'")
	}

	if (outHover){
		mvStop()
	}else{
		mvStart()
	}
	
	
}

function writeDivs(){
	if (ns4){
		document.write("<ilayer name=divOuter width=750 height="+divHeight+">")
		
		for (i=0;i<imgArr.length;i++){
			document.write("<layer name=divAds"+i+">")
			document.write(imgArr[i]+" ")
			document.write("</layer>")
		}
		document.write("</ilayer>")
		document.close()
		for (i=displayImgAmount;i<imgArr.length;i++){
			eval("document.divOuter.document.divAds"+i+".clip.right=0")
		}
	}else{
		document.write("<div id=divOuter style='position:relative' width=750 height="+divHeight+">")
		
		for (i=0;i<imgArr.length;i++){
			document.write("<div id=divAds"+i+" style='position:absolute;clip:rect(0,"+divWidth+","+divHeight+",0)'>")
			document.write(imgArr[i]+" ")
			document.write("</div>")
		}
		document.write("</div>")
		for (i=displayImgAmount;i<imgArr.length;i++){
			eval("document.all.divAds"+i+".style.clip='rect(0,0,"+divHeight+",0)'")
		}
	}
}