Neat. I did a related project a little while ago. I wasn't interested in how far I can see from everywhere, so much as what I can see from one place in particular.
So in mine you can click on a spot and it draws black lines over any land that is occluded by terrain, within 100km.
(But all with AI-generated JavaScript, not cool Rust and SIMD stuff)
I am not sure if I'm experiencing what you describe. I just see a radiating circle of black lines, no matter where I click. I decided to click a local, notable "long line" viewpoint -- Lick Observatory outside San Jose. From here, on a clear day, you can see Half Dome in Yosemite, 120mi away. I still just see a black circle.
Are you standing on a raised platform when you see the Half Dome?
This is what I get when I set the observer height to 20m, and increase the "max distance" to 300km (200km = ~124 miles so may not be enough).
https://img.incoherency.co.uk/6478
It's also possible that the half dome is too short and the sampling rate of the line-of-sight jumps over it!
It seems that sometimes it fails to load the height map, try reloading the page. You should see terrain shading if it's loaded properly.
I think the lines indicate areas that you can't see?
It's buggy. Mission peak shows much of the bay area occluded.
> But all with AI-generated JavaScript, not cool Rust and SIMD stuff
Heh, I almost hit back at the "in Rust" mention.
Would the end result have been different if it were done in python calling C libraries for performance? I strongly doubt it.
Isn't cross language function calling expensive? I assume it is significant.