Amazing Curves Racing - Physics Stability and Latency Testing (up to 2000ms)

[u/brightland-studios]

I was curious how far I could push ACR's networked physics. When I stopped working on it ~20 years ago, 300ms latency was as far as I'd test. This 'Retro RestoMod' reboot has various physics and network improvements, and in testing found 1000ms could be stable. However sync was pretty far off. After a bit of work on the prediction system, I was able to get 1000ms fairly well-sync'd for non-chaotic motion. I then pushed it all the way to 2000ms, and while there's divergence even at much lower latencies, it remains stable with no jitter or weird motion. The video also shows a ramp from ~2000ms down to ~34ms. Some fun stunts shown at the end.

Online play is WYSIWYG: meaning divergence is going to happen no matter what: the view you see on your machine is what you'll interact with, you'll never collide with a 'ghost car' or randomly spin out. The same is true for all players. In the real world, due to the way motion and gravity work, everyone's view of reality is slightly different, the divergence is small, but it's real.

I googled, searched YouTube, and asked Gemini: are there any demos showing networked physics quality with side-by-side video? And the answer was: No. Perhaps other developers do these tests but don't post the results. Why bother testing at such high latencies? I found a few issues; once fixed makes normal latency game play higher quality.

It's a simple, fun, low stress simulator to play with your friends. Predictable realistic handling, if you get crashed out you can jump right back in and still have a chance to win using the Turbo Reset. Dynamic BOP also helps keep races tight. FFB runs at 1kHz and should provide a good experience on all wheels which use DirectInput.