function change_butterfly() {
    var rand;
	var ddx;
	var ddy;
	rand = Math.random();
	

	if (rand < 0.8) {
		
		
		if (rand < 0.6) {
			if (rand < 0.4) {
				if (rand < 0.2) {
					ddx = 650;
					ddy = Math.floor(Math.random()*500)+0;
				}
				else {
					ddx = 600;
					ddy = Math.floor(Math.random()*500)+0;
				}
			}
			else {
				ddx = Math.floor(Math.random()*650)+00;
				ddy = 600;
			}
		}
		else {
		ddx = Math.floor(Math.random()*500)+100;
		ddy = -10;
		}
		
	}
	else {
		ddx = Math.floor(Math.random()*500)+100;
		ddy = -10;
	}
	

	document.getElementById("butterfly").style.left = (ddx+ "px");

    document.getElementById("butterfly").style.top = (ddy+ "px");

}


function getElementsByName_iefix(tag, name) {
     var elem = document.getElementsByTagName(tag);
     var arr = new Array();
     for(i = 0, iarr = 0; i < elem.length; i++) {
          att = elem[i].getAttribute("name");
          if(att == name) {
               arr[iarr] = elem[i];
               iarr++;
          }
     }
     return arr;
}



function an(img_taktil, src) {
		
				document.images[img_taktil].src= src;
		
}