This Gallerytemplate uses the PhotoSwipe script version 4.1.3 by Code Computerlove and was contributed by Rolf Tjassens.
NOTE: The smartytemplate makes use of a method described at https://www.cmscanbesimple.org/blog/getting-the-image-dimensions-in-smarty
Because of this you need to add this line to the config.php file: $config['permissive_smarty'] = 1;
Documentation can be found at https://photoswipe.com
Files that come with PhotoSwipe are stored in assets/modules/Gallery/templates/photoswipe/
PhotoSwipe is free to use for personal and commercial projects. It falls under the MIT license.