I am having some trouble in my quest to build a Drupal 7 custom node based image gallery module. I've got many things that are already working, but now I need AJAX to load and manipulate comments.
###What I am doing
I've created a Drupal 7 one-image-per-node image gallery; it uses relationships, EVA and even BBQ for deep linking, when viewing the 'gallery' node, EVA feeds in the thumbs and helpful attributes, e.g. URL to full image, url to actual node. I have jQuery in my gallery node, which AJAX preloads the full images on thumb click & manipulates them for fast dynamic full screen browsing, it works perfectly! Even the BBQ deep-linking which was difficult. Some of my gallery display js code is based on http://manos.malihu.gr/tuts/sideways_jquery_fullscreen_image_gallery.html.
###Current Status
I am trying all angles to bring in the comments. Using pure jquery, as I've tried, returns too much forcing a whole node to load to just pull out the comments. Now I have finally figured out the menu callback system. I had no idea that was even there! I am playing around with that now to see what I can bring in that way. Also, I am unsure about Services & Json or the views json output module and if that would be useful to me in this situation? Would json be better to call comments?
###Update I've got it working, though it is not in the most elegant way. I'll post what I have as an answer and then try and figure out some other possibilities.