var actImgI = null;

function galleryPreview(i){
  
   actImgI = i;
  //alert(1);
   document.getElementById('imgPreview').style.height = "291px";
   document.getElementById('imgCont').style.width = productImageWidths[i]+"px";
   document.getElementById('imgCont').style.display = 'block';
   var photoId = productImageIds[i];
   document.getElementById('imgPreview').innerHTML = "<img src='?img:"+photoId+":3000:291' />";
   document.getElementById('productDescription').innerHTML = productImageDescriptions[i];
   productDescription
   //window.location.href = "#imgGallery";
  //alert(2);
}

function galleryPrev(){
  if(actImgI > 0 && productImageIds[actImgI-1] > 0){
    galleryPreview(actImgI-1, 100);
  }
}

function galleryNext(){
  if(productImageWidths.length > actImgI+1 && productImageIds[actImgI+1] > 0){
    galleryPreview(actImgI+1, 100);
  }
}