1. Sort images from metadata fields?
You could use a Flickr account as a source of images by using the following settings in your gallery's XML file:
useFlickr="TRUE"
flickrUserName="your_flickr_username"
Then, you could use the flickrSort Pro Option which gives you some control over the order in which the images are displayed.
The Juicebox Flickr options can be found here.
2. Display select metadata: captions, filenames et al?
It is not yet possible to extract metadata for use as the image's <title> or <caption>.
Currently, it is possible to use the image's File Name for the <title> and/or <caption> and, additionally, the linkURL for the <caption> (via JuiceboxBuilder's 'Images -> Titles' and 'Images -> Captions' drop-down options at the top).
3. Update a site on the fly by adding images to a folder/directory, without entire re-export?
If using Flickr as a source of images, you could upload new images to your Flickr account and they would be displayed in your Juicebox gallery next time it is viewed without having to modify any gallery files.
Alternatively, you could use the following PHP code as your gallery's XML file. It will read and display all images in a folder named 'images'.
<?php
header("Content-type: application/xml");
function GetDirArray($folder)
{
$handle=opendir($folder);
while ($file=readdir($handle))
{
if ($file!="." && $file!="..")
{
$ret[]=$file;
}
}
closedir($handle);
sort($ret);
return $ret;
}
$gallery=GetDirArray('images');
echo '<?xml version="1.0" encoding="UTF-8"?>';
echo '<juiceboxgallery galleryTitle="Juicebox Gallery">';
for ($i=0; $i<sizeof($gallery); $i++)
{
echo '<image imageURL="images/'.$gallery[$i].'" thumbURL="images/'.$gallery[$i].'" linkURL="" linkTarget="">';
echo '<title></title>';
echo '<caption></caption>';
echo '</image>';
}
echo '</juiceboxgallery>';
?>
Place the above code in a file named 'config.php', place the file in your gallery folder and add the following to your gallery's embedding code:
(You may wish to modify the code to handle thumbnails in a similar fashion.)
Each time you upload images to the 'images' folder, they will automatically be displayed in the gallery when the gallery is viewed.