/**
 *  pos and pictures array in lbljavascript
 **/
function NextPicture() {
        
    if (pos < pictures.length - 1) {    
        pos++;
    } else {
        pos = 0;
    }
        
    document.getElementById("largePicture").src=pictures[pos];
}

function PreviousPicture() {
    if (pos > 0) {    
        pos--;
    } else {
        pos = pictures.length - 1;
    }
     
    document.getElementById("largePicture").src=pictures[pos];
}