Camera Smoothing causes jittering in Player again

[Wladastic]

Tested versions

• Reproducable in 4.2

System information

Windows 10, Mac OS 14.2 Godot 4.2.stable.official

Issue description

Issue was already fixed in Godot 3.x but reappeared:
#43800

It is essentially the same issue as before, when moving the player and having camera Position Smoothing enabled, it jitters the whole screen when following the Player.

Steps to reproduce

Camera on 1920x1080,
Stretch: Viewport, keep_height, scale: 1.0, scale mode: fractional

Character Body 2D for Player with AnimatedSprite2D and AnimationPlayer/AnimationTree.
When I move slow around 150 velocity it is fine, when above 400, then it appears like the Character body is jittering back and forth.

Minimal reproduction project (MRP)

Will look for some youtube videos where this was also mentioned (recent video of around 4 weeks ago)

[Calinou]

This will occur if your monitor's refresh rate or FPS cap differs from the physics FPS defined in the Project Settings. As a workaround, set the Camera2D's process callback property to Physics instead of Idle. A proper solution is to use physics interpolation, which hasn't been implemented in 4.x yet (and not in 2D yet either). Use https://github.com/lawnjelly/smoothing-addon/tree/4.x in the meantime.

Also note that #84137 can make this issue more noticeable, even if workarounds or physics interpolation are used.

Closing in favor of godotengine/godot-proposals#6389 and other related issues, as there are many open issues on the subject already.