Kyle Halladay, a game programmer, writes about graphics hacks, DirectX hooking, Vulkan and Game Boy Advance development.
HN commenters link his Notepad rendering posts to explain how the demos work, and his post on a game-dev hack that exploited a EULA.
> The first thing that jumped out at me in this story was the part about sending machine code over the network to be executed by the game. It had never occurred to me that this was possible, despite it being obvious in hindsight.
This is a good reminder that us software devs generally live in bubbles, not really thinking about or (sometimes intentionally) ignoring things that are not immediately relevant to our work.
The author appears to mostly work in game development, specifically shading, 3D, and engine development. Generally you think very little about writing secure code in those fields.
You can actually see him going down the "low-level rabbit-hole" if have a look at his posts: http://kylehalladay.com/archive.html
As far as I know, most of this stuff still works. There might be some security boundaries that apps can opt into, but most of them do not. So something running as your user, you can probably manipulate the UI of.
There's been some amusing ones even not so long ago, like this one:
http://kylehalladay.com/blog/2020/05/20/Rendering-With-Notepad.html
edit: Bad example, they are using WriteProcessMemory. Still a lot of fun, but not the same. I was thinking of this:
https://twitter.com/steveklabnik/status/1263190719721766918
The parts where it exits fullscreen and starts messing around with separate windows is really well done. In a way it's playing with the limits of what defines a demo (ie. the user's desktop is part of the performance), which is something I love to see. Same with the notepad animation part. I wonder if they implemented their own notepad-alike from scratch or it they used something like this: https://kylehalladay.com/blog/2020/05/20/Rendering-With-Notepad.html
Related, and recently discussed here[1], a ray tracer that uses Notepad for its UI: http://kylehalladay.com/blog/2020/05/20/Rendering-With-Notepad.html
Though the ray tracer used a more complicated, and more efficient way of manipulating the Notepad "framebuffer".
[1] https://news.ycombinator.com/item?id=23246221
Amazing story. Here is one of my favorite ones as well, when Naughty Dog intentionally exploited EULA to fix Ratchet and Clank.
https://kylehalladay.com/blog/2019/12/04/Recreating-A-Dirty-Gamedev-Hack.html
Won't somebody please think of backcompat with the Notepad raytracer?![1]
[1] http://kylehalladay.com/blog/2020/05/20/Rendering-With-Notepad.html