Show HN: Asdf Overlay – High performance in-game overlay library for Windows

68 storycraft 16 5/30/2025, 6:27:44 PM github.com ↗
I am making a open source overlay library.

Game overlay is for rendering contents on top of game screen. Representative examples are Discord and Steam in-game overlay. They are complicated because it has to hook rendering part of a game.

Asdf overlay provides easy to use interfaces for rendering on top of game screen. I recognize game performance degradation due to overlay rendering, so GPU shared texture was used to avoid CPU framebuffer copy. Asdf Overlay is capable of rendering full screen overlay without noticeable performance loss.

Comments (16)

jnettome · 1d ago
I've tried to implement this so many times, and it's always been a pain. I really like this Rust implementation — I'm going to take a closer look and run some tests now. Congrats on the launch!
lwansbrough · 1d ago
Have you had any issues with EAC or Vanguard?

I'd like to see if I can get something like this to work with Flutter, though I suspect it would be a challenge to integrate with Skia.

storycraft · 18h ago
Unfortunately most anticheats does not allow loading untrusted dll in game. But It's on plan to release code signed library.

If Flutter provides an interface to render on offscreen texture, integrating with it shouldn't be that hard.

lwansbrough · 17h ago
I did end up looking into it a bit. One would have to build a new Embedder Engine for Flutter, which they provide examples for. But the implementation is significant. Probably achievable for a small team.
MarcelOlsz · 1d ago
This looks great and might solve some woes in the iRacing/simracing community. Is it possible to embed another app a la OpenKneeboard? Also any future plans of having it working in OpenXR/OpenVR?
storycraft · 18h ago
Although I am not providing easy to use interface for that, It is possible to overlay another app to game. Not sure about OpenXR/OpenVR.
next_coder_ · 1d ago
That's cool, I can imagine quite some appliances for game dev.
terminalbraid · 1d ago
Is this related to asdf vm or the common lisp build system?
Alifatisk · 1d ago
I thought this was related to asdf-vm!
pawelduda · 1d ago
No
Sleaker · 1d ago
I feel a little dumb asking this, but why is 'asdf' used in the moniker? Is there any significance to it?
storycraft · 18h ago
It was the first name that came to mind when I was thinking about easy to remember name. Other than that, there's no significance.
MarcelOlsz · 1d ago
Default character movement keys in videogames, middle 3 fingers resting on awd by default.
Sleaker · 23h ago
I don't really buy this. Asdf is where your fingers land for general purpose typing, which predates computers, thats not something gaming gets to own.

Default movement in games is also WASD.

MarcelOlsz · 21h ago
Oh whoops I completely messed up lol.
singron · 1d ago
wasd are the default movement keys. asdf is just the qwerty left hand home row.