asdfffdsa: feel free to expand on my code and use it however you wish. Giving me credit is welcome but not required. I do not like software licensing, as you can probably tell from my embedded "disclaimer". Users should exercise responsibility and not expect others to pay for their mistakes. You can use whatever license you feel comfortable with. A lot of people here seem to prefer GPL for some reason. To me, GPL seems a little like clapping your hands in applause after dipping them in cyanoacrylate adhesive.
One useful feature to add would be hotkey monitoring. I was thinking that reposition and/or resize could be done using the last adjusted settings, when the "next page" key is released. That gives time for a PDF (or other ebook format) to render the page and finish updating the framebuffer, controlled by how long the user holds the key. Also, it would be nice to have a continuous adjustment mode using the 5-way pad, using the "fast" mode while pressed, with full flash draw on release. And the ability to move and resize horizontally would be useful too. But most importantly, have fun with it!
In another recent thread (
here), a new program was provided that also directly reads the framebuffer. What is special about it is that it does OCR to convert the currently selected (underlined) book title back to text. I think this is the beginning of something great.