//Hauptnavigation

var buttonheight=15;
var buttonheight_Level2=15;

var DiffRechnungLoaded = false;
var TrigonometrieLoaded = false;

var DHTML = 0, DOM = 0, MS = 0, NS = 0, OP = 0, FF = 0;

var BrowserTyp = "";
var BesucherZaehlen = 0;

function MathematikInit(b_zaehl) {

    BesucherZaehlen = b_zaehl;
    
    DiffRechnungLoaded = false;
    TrigonometrieLoaded = false;

    var elem;

	GetBrowser();

    if (!DOM) {
	  if (NS) {
         window.location.href="Index-Zwei.html";
		 return;
	  }
	}

	var Knoten = document.getElementById("DynamischeButtonleiste").firstChild;
	var ebene1_Zaehler=0;
	var ebene2_Zaehler=0;
	var i=0;
    while (Knoten != null) {
      while (!Knoten["id"]) Knoten = Knoten.nextSibling;
      var KnotenId = Knoten.getAttribute("id");
	  ebene1_Zaehler = parseInt(KnotenId.substring(3,5),10);

	  if (KnotenId.length == 7) {
	    ebene2_Zaehler = parseInt(KnotenId.substring(5,7),10);
	  }
	  else {
	    ebene2_Zaehler = 0;
	  }

	  if(ebene2_Zaehler != 0) {
        document.getElementById(KnotenId).style.visibility="hidden";
	  }
	  else {
        document.getElementById(KnotenId).style.visibility="visible";
      	document.getElementById(KnotenId).style.top=i*(buttonheight+2);
		i++;
	  }		
      Knoten = Knoten.nextSibling;

    }	
    document.getElementById("DynamischeButtonleiste").style.visibility="visible";
}


function GetBrowser() {


  if (window.opera) {
      OP = 1;
      BrowserTyp="OP";
    }
  if(document.getElementById) {
    DHTML = 1;
    DOM = 1;
  }
  if(document.all && !OP) {
    DHTML = 1;
    MS = 1;
    BrowserTyp="MS";
  }
 if(document.layers && !OP) {
    DHTML = 1;
    NS = 1;
    BrowserTyp="NS";
  }
 if (enthaelt(navigator.userAgent, "Firefox")) {
    FF = 1;
    BrowserTyp="FF";
  }
 if (enthaelt(navigator.userAgent, "Netscape")) {
    NS = 1;
    BrowserTyp="NS";
  }

}

function enthaelt(zeichenkette_in, gesuchte_zeichenkette) {
    m=0;
    for (n=0;n<zeichenkette_in.length && n < 200;n++) {
	  if (zeichenkette_in.charAt(n) == gesuchte_zeichenkette.charAt(m)) {
	    m++;
	  }
	  else {
	    m=0;
	  }
	  if (m >= gesuchte_zeichenkette.length) {

		return true;
	  }
	  
	}

    return false;
}

function selectButton(button_level) {

    if (MS) {
    	document.GifAnimation.src="BK_G_3d.gif";
    	document.SpezGif.src="images/Animation1.gif";
    }

    var Knoten = document.getElementById("DynamischeButtonleiste").firstChild;
	var ebene1_Zaehler=0;
	var ebene2_Zaehler=0;
	var topAbstand=0;
    while (Knoten != null) {
      while (!Knoten["id"]) Knoten = Knoten.nextSibling;
      var KnotenId = Knoten.getAttribute("id");
	  ebene1_Zaehler = parseInt(KnotenId.substring(3,5),10);
	  if (KnotenId.length == 7) {
	    ebene2_Zaehler = parseInt(KnotenId.substring(5,7),10);
	  }
	  else {
	    ebene2_Zaehler = 0;
	  }

	  if(ebene1_Zaehler == button_level && ebene2_Zaehler != 0) {
         if(document.getElementById(KnotenId).style.visibility=="hidden") {
			if (FF && ebene2_Zaehler == 1) topAbstand+=4;
            document.getElementById(KnotenId).style.visibility="visible";
    	    document.getElementById(KnotenId).style.top=topAbstand;
			topAbstand+=buttonheight_Level2+1;
         }
		 else {
            document.getElementById(KnotenId).style.visibility="hidden";
		 }
	  }
	  else {
         if(document.getElementById(KnotenId).style.visibility!="hidden") {
	  	   if(ebene2_Zaehler != 0) {
	      document.getElementById(KnotenId).style.visibility = "hidden";
//      	      document.getElementById(KnotenId).style.top=topAbstand;
//		      topAbstand+=buttonheight_Level2+1;
		   }
		   else {
      	      document.getElementById(KnotenId).style.top=topAbstand;
		      topAbstand+=buttonheight+2;
		   }
	     }
	  }
      Knoten = Knoten.nextSibling;
    }	



return;
}


function chgBesZaehl() {
  if (BesucherZaehlen == 0) BesucherZaehlen = 1;
  else BesucherZaehlen = 0;
}

function selectAnzeige(newHTML, SteuerFlag) {

    if (MS) {
    	document.GifAnimation.src="BK_G_3d.gif";
    }
    
    if (SteuerFlag == 1) {
      newHTML+="&param3=";
      newHTML+=BrowserTyp;
    }
    if (BesucherZaehlen == 0)  {
      if (newHTML.indexOf("?") == -1) newHTML+="?bz=no";
      else newHTML+="&bz=no";
    }
    
    var inhalt = "<object data='"+newHTML+"' type='text/plain' width='780px' height='540px'></object>";

    document.getElementById("InhaltDiv").innerHTML=inhalt;

return;
}