Replace Rapier with Avian

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Rapier → Avian

bevy_firework Is a wonderful crate.
I'd love to do some particle physics but the current Physcis Backend is not supported, hence the migration.

bevy_hanabi has superior GPU performance but doesn't know about the physical world so it is a little booring for what I have planned, maybe I'll combine the two in the future to get the best of both worlds (physics and raw GPU power).

Montage during migration

Colliders need to be twice as large in Avian:

Not setting colliders to static leads to only the top face being collidable?
Every block basically acts like a ladder

CleanShot.2026-02-02.at.21.04.15.mp4

Bevy fps controller doesn't set Y-offset by default, leading to the player collider getting stuck on basically thin air

CleanShot.2026-02-02.at.21.29.05.mp4

Excerpt from Avian itself

How does Avian compare to Rapier and bevy_rapier?

Rapier is the biggest and most used physics engine in the Rust ecosystem, and it is currently the most mature and feature-rich option.

bevy_rapier is a great physics integration for Bevy, but it does have several problems:

• It has to maintain a separate physics world and synchronize a ton of data with Bevy each frame
• The source code is difficult to inspect, as the vast majority of it is glue code and wrappers for Bevy
• It has poor docs.rs documentation, and the documentation on rapier.rs is often outdated and missing features
• Overall, it doesn’t have a native ECS-like feel

Avian on the other hand is built for Bevy with Bevy, and it uses the ECS for both the internals and the public API. This removes the need for a separate physics world, reduces overhead, and makes the source code much more approachable and easy to inspect for Bevy users...
https://docs.rs/avian3d/latest/avian3d/index.html#how-does-avian-compare-to-rapier-and-bevy_rapier

Changes

After migrating to Avian I noticed severe

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prelude 🤤

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This is a side quest.
During the saving of a world you'd get

Saving world...
Saving world...
Saving world...
Saving world...
Saving world...

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Didn't seem to happen before..

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Maybe my setup changed?