/********************************************************************************
版權 (C) 2001 DHTMLCentral.com
這個Script由Thomas Brattli所做其版權為DHTMLCentral.com所有.
請同學光臨此站會有意想不到的收穫 (鈺)
ZoomFade 
********************************************************************************/
//檢查瀏覽器種類
function lib_bwcheck(){ //Browsercheck (needed)
	this.ver=navigator.appVersion
	this.agent=navigator.userAgent
	this.dom=document.getElementById?1:0
	this.ie5=(this.ver.indexOf("MSIE 5")>-1 && this.dom)?1:0;
	this.ie6=(this.ver.indexOf("MSIE 6")>-1 && this.dom)?1:0;
	this.ie4=(document.all && !this.dom)?1:0;
	this.ie=this.ie4||this.ie5||this.ie6
	this.mac=this.agent.indexOf("Mac")>-1
	this.opera5=this.agent.indexOf("Opera 5")>-1
	this.ns6=(this.dom && parseInt(this.ver) >= 5) ?1:0; 
	this.ns4=(document.layers && !this.dom)?1:0;
	this.bw=(this.ie6 || this.ie5 || this.ie4 || this.ns4 || this.ns6 || this.opera5 || this.dom)
	return this
}

var bw=new lib_bwcheck()

//(顏色變化設定,(1)前面各段字的顏色(2-5)最後一段字的色變)
zColor=new Array('#aaaaaa','#aaaaaa','#aaaa99','#aaaa88','#ffff33')
var zEndSize=70             //最後字體大小
var zSpeed=50               //Zoom 速度
var zAddSize=5              //Zoom過程的各次字體增量
var zFadeSpeed=200          //顏色變化速度
var zFont='Arial Black,Arial,Helvetica'     //指定字型
var zHide=true              //結束後是否消失
var zHideWait=200           //消失前的時間
var zStartSize=10           //開始的字體大小
var zEndCode="location.href='逐項說明.htm'" // 如果指定文字結束時消失下一個出現的指令

//以下文字: (將逐段出現並消失)
zText=new Array('歡迎光臨','黃鈺','力學教室','黃鈺力學教室')


/********* 以下無需更動 ***********/
var zFont='Arial Black,Arial,Helvetica' //Font

//物件函數
function makeZoomObj(obj,font,size,endsize,color,text,zspeed,fadespeed,addsize,hide,hidewait,endcode){
   	this.css=bw.dom? document.getElementById(obj).style:bw.ie4?document.all[obj].style:bw.ns4?document.layers[obj]:0;	
   	this.writeref=bw.dom? document.getElementById(obj):bw.ie4?document.all[obj]:bw.ns4?document.layers[obj].document:0;	
	this.zoomWrite=b_zoomWrite;	this.zoomIt=b_zoomIt; this.fadeIt=b_fadeIt;	this.zoomFade=b_zoomFade;
	this.font=font; this.color=new Array(); this.color=eval(color);	this.text=new Array(); this.text=eval(text);
	this.zspeed=zspeed; this.fadespeed=fadespeed; this.addsize=addsize; this.endcode=endcode
	this.hide=hide; this.hidewait=hidewait; this.size=size; this.startsize=size; this.endsize=endsize
	if(size<endsize){this.way="<"; this.addsize=this.addsize
    }else{this.way=">"; this.addsize=-this.addsize}
	if(bw.dom || bw.ie4){ //Setting the style properties
		this.css.fontFamily=this.font; this.css.fontSize=this.size+"px"; this.css.color=this.color[0]
	}
	this.obj = obj + "Object"; 	eval(this.obj + "=this"); return this
}
function b_zoomFade(num){
	if(num<this.text.length){
		this.size=this.startsize
		this.zoomIt(num,'this.zoomFade('+(num+1)+')')
	}
	else if(num==this.text.length) this.fadeIt(0,'this.zoomFade('+(num+1)+')')
	else if(this.hide) setTimeout(this.obj+".css.visibility='hidden'; eval("+this.obj+".endcode)",this.hidewait)
}
function b_zoomWrite(num,cnum){
	if(bw.ns4){
		this.writeref.write('<span style="text-align:center; font-size:' +this.size+'px; font-family:'+this.font+'; color:'+this.color[cnum]+'">'+this.text[num]+'</span>')
		this.writeref.close()
	}else this.writeref.innerHTML="<center>"+this.text[num]+"</center>"
}
function b_zoomIt(num,fn){
	if(eval(this.size+this.way+this.endsize)){
		if(this.size==this.startsize || bw.ns4) this.zoomWrite(num,0)
		if(bw.dom || bw.ie4) this.css.fontSize=this.size+"px"
		this.size=this.size+this.addsize
		setTimeout(this.obj+".zoomIt("+num+",'"+fn+"')",this.zspeed)
	}else eval(fn)	
}
function b_fadeIt(num,fn){
	if(num<this.color.length){
		if(bw.ns4) this.zoomWrite(this.text.length-1,num)
		else this.css.color=this.color[num]
		num++
		setTimeout(this.obj+".fadeIt("+num+",'"+fn+"')",this.fadespeed)
	}else eval(fn)	
}
/*Initiates the object, shows it and starts the zoom
****************************************************************************/
function zoomInit(){
	if(bw.bw){
		oZoom=new makeZoomObj('divZoom',zFont,zStartSize,zEndSize,'zColor','zText',zSpeed,zFadeSpeed,zAddSize,zHide,zHideWait,zEndCode)
		oZoom.zoomFade(0)
		oZoom.css.visibility='visible'
	}
}