I was working my way through the Terraform Two-Tier example and after finding omissions I wrote down the missing parts and posted them to a GitHub gist. I used a gist as, I think, search engines will likely rank this higher than a posting here in my blog and so is better for folks looking for help.
I don't use GitHub gists much, but, apparently, I have been using them them for a long time -- 11 years! I had forgotten about some of the work I had done and dropped into gists. The horizon chart gist was part of my Horizon Chart blog post. I don't seemed to have posted anything about PDF Thumbnailer, however.
I originally created PDF Thumbnailer as part of a larger project to enable public commentary on South Kingstown, RI's budget. (SK is my home town.) When this project started in 2007 there were no available online tools for multiple users commenting on a PDF. So I needed to build one. The web interface consisted of just two principle pages, an overview page containing thumbnails of the whole budget with comment indicators laid over the thumbnails, and a details page of the whole budget and commentary interleaved.
To interleave the comments I needed to place them between the text, charts, and tables of the budget document. Parsing and rebuilding the PDF or converting it to HTML and rending it in the browsers of the time was more work than I could commit too. Instead, I compromised on the spacial proximity of a comment and its context. I converted the PDF pages to images and sliced each image into 1" tall strips. I could then interleave strips and comments on the details page as needed. While a comment was not attached to the context it was close enough to establish the connection.
In these sketches the pages are bounded in red, the strips in blue, and the comments in purple.
The project was never completed, but it did leave behind the thumbnail creator. I rebuilt it this morning and here are a few example pages from Rescue.org's recent report Missing Persons: Refugees Left Out and Left Behind in the SDGs