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fps-herotoday at 11:03 AM1 replyview on HN

I find it weird today that we are still fascinated by video wall papers.

This was literally my first hack I did in high school in 2005. Doing something I’d never seen done before, a video wallpaper.

Step one, grab a handle to the video memory serving the wall paper. My “game trainer cheats” experience served me well. That was easy.

I had to figure out the hard way that per pixel calculations are extremely CPU taxing, the YUV to RGB video color space conversion. With a pirated Intel compiler I could get the naive blit into memory videy background working.

But then I wondered how other video apps were working so efficiently?

They used a GPU overlay! How it worked is you’d designate a color on your screen as the overlay color, and, when the screen was rendered, any pixel that was the overlay color was swapped with the full screen rendered video. I forget the specifics, it was some directX api. So, set the wallpaper to the hottest hot pink, run the renderer, and bobs your uncle, video wallpaper.

Everyone I showed this to was amazed, I really though I was on to something! Trouble was, I couldn’t get the damn thing to run on other people’s computers!

Little did I know or understand about the dreaded VCruntime redistributable. It wasn’t until 10 years later when I started working in industry I learned about “software distribution”. Linux makes it too easy, windows makes it too hard, static linking everything that isn’t network facing is probably the right approach.

I was so annoyed when Vista had the video wallpaper feature. “Man I was doing this years ago!”.


Replies

jbs789today at 11:15 AM

So in summary… it’s fun when you do it but “weird” when others do the same.

This is life. We discover things for ourselves, on our own time.