var dummyImg = new Image();
var currentActiveObject = dummyImg;

function naviOut( htmlObject ){
    if ( currentActiveObject.name != htmlObject.name ) { 
        htmlObject.src='pix/but_'+ htmlObject.name +'.png';
    }	
}

function naviIn( htmlObject ){
    htmlObject.src='pix/but_'+ htmlObject.name +'_hi.png';
}

function naviClick( htmlObject ){
	currentActiveObject.src = 'pix/but_'+ currentActiveObject.name +'.png'; 
	currentActiveObject = htmlObject; 
	currentActiveObject.name = htmlObject.name; 
	htmlObject.src = 'pix/but_'+ htmlObject.name +'_hi.png';
}

function unsetNavi(){
    currentActiveObject.src = 'pix/but_'+ currentActiveObject.name +'.png';
    currentActiveObject = new Image();
}

function toggleEventsPicture( num ){
    for( var i=6; i>0; i--){
        if(  document.getElementById('events-image'+ i) ){
            document.getElementById('events-image'+ i).style.visibility = 'hidden';
  	}  
    }	
    document.getElementById('events-image'+ num).style.visibility = 'visible';
}

function toggleNextSongtext( num ){
    var maxnum=20;
    for( var i=maxnum; i>0; i--){
        if(  document.getElementById('songtext-'+ i) ){
  	    document.getElementById('songtext-'+ i).style.visibility = 'hidden';
  	}  
    }	
    num++;
    while ( ! document.getElementById('songtext-'+ num) ){
        num++;
        if ( num > maxnum ){
            num = 0;
        }
    }        		 
    document.getElementById('songtext-'+ num).style.visibility = 'visible';
}

function toggleLastSongtext( num ){
    var maxnum=20;
    for( var i=maxnum; i>0; i--){
        if(  document.getElementById('songtext-'+ i) ){
            document.getElementById('songtext-'+ i).style.visibility = 'hidden';
        }  
    }	
    num--;
    while ( ! document.getElementById('songtext-'+ num) ){
        num--;
        if ( num < 0 ){
            num = maxnum;
        }
    }        		 
    document.getElementById('songtext-'+ num).style.visibility = 'visible';
}

function closeSongtext( num ){
  document.getElementById('songtext-'+ num).style.visibility = 'hidden';
}


//