Physics in `physics.ts` and Misskey's Bubble Game are framerate-dependant

[CenTdemeern1]

💡 Summary

Physics in Misskey's Bubble Game and physics.ts were likely meant to run consistently across devices and screens, but instead they run faster at higher frame rates.

This was first brought up on Sharkey's issue tracker: https://activitypub.software/TransFem-org/Sharkey/-/issues/684

I have fixed this bug and I am creating issue before creating the accompanying pull request.

🥰 Expected Behavior

Misskey's Bubble Game and physics.ts should run at the same speed on a 60hz screen and a 120hz screen.

🤬 Actual Behavior

Misskey's Bubble Game and physics.ts run at twice the speed on a 120hz screen compared to a 60hz screen.

📝 Steps to Reproduce

Open Misskey's Bubble Game or find the hidden physics easter egg. Compare behavior across different refresh rate screens. (Note: Safari calls window.requestAnimationFrame at 60hz even on higher rate screens by default for consistency. This can be bypassed via a feature flag.)

💻 Frontend Environment

Desktop:

• Model and OS of the device(s): Mac Mini M2 running macOS Sequoia 15.0.1 (24A348)
• Browser: Arc Version 1.66.0 (55166) running Chromium Engine Version 130.0.6723.70
• Server URL: localhost
• Misskey: 2024.10.2-alpha.2 (a96f09cee352f8ae7cc11c3dd45e0182a5623350)

Mobile

• Model and OS of the device(s): iPad Pro (11 inch) (3rd generation) running iPadOS 18.0.1
• Browser: Safari 18
• Server URL: (local IP address)
• Misskey: 2024.10.2-alpha.2 (a96f09cee352f8ae7cc11c3dd45e0182a5623350)

🛰 Backend Environment (for server admin)

• Installation Method or Hosting Service: development environment
• Misskey: 2024.10.2-alpha.2 (a96f09cee352f8ae7cc11c3dd45e0182a5623350)
• Node: v22.9.0
• PostgreSQL: postgres (PostgreSQL) 15.8
• Redis: Redis server v=7.4.0 sha=00000000:0 malloc=jemalloc-5.3.0 bits=64 build=c7883ba45b24b5e8
• OS and Architecture: Mac Mini M2 running macOS Sequoia 15.0.1 (24A348) on Apple Silicon

Do you want to address this bug yourself?

• [x] Yes, I will patch the bug myself and send a pull request

[KisaragiEffective]

Thanks for forwarding report. I marked this as actual bug because a few people have reported same issue from distinct server (plus the Sharkey's thread).