[smokel]

Yup. I wrote a TSR program to extend Deluxe Paint II on PC with animation features. Never heard about APIs, and simply copied data from the VGA memory, overlaying my own user interface on top of DP.

The thought of doing this with contemporary systems just seems ... wrong :)

[ddalex]

I wrote lots of TSR extensions, I remember one that would allow you to switch between DOS programs.... it broke when the next version of DOS came out.

I was most fond of my image viewer program that worked only on my video card (a cirrus logic) but was 10x faster then others because it used some hw acceleration on the card (not remembering details right now).

It's basically impossible to replicate this level on todays extra-locked-down machines - the bar to entry and just tinker is so much higher.

[kimixa]

It's all still available, arguably more accessible from a cost and documentation point of view - I'd argue that the bar to getting something is so much higher.

You can today start banging registers on GPUs, or write your own shader programs, there's well documented modern hardware (e.g. [0]) and completely open-source drivers just sitting there for reference. The issue is that there's so moving parts now that to get anything visible to actually happen it's not just wiring up a couple of registers, but thousands just to get it into a state you can even see the registers you want, then a thousand more.

[0] https://gpuopen.com/amd-gpu-architecture-programming-documen...

[smokel]

Hah, I spent countless hours poking bits around in the Cirrus Logic card that I had.

I found an undocumented (to me, at least) mode that showed 16-bit images by alternating two 8-bit images. I put it in a demo to show at a demoparty, but the projector system did not have a compatible VGA card :(

[SmellTheGlove]

Well back then we didn’t have all of that memory for those fancy abstraction layers. Sticking your finger in the framebuffer probably wasn’t the worst way to do that!