Particles system jitters back & forth when pausing the SceneTree if Engine.time_scale != 1.0

[razcore-rad]

Godot version

v4.0.2.stable.official [7a0977c]

System information

Ubuntu 22.10, Vulkan, NVIDIA GeForce RTX™ 2060 / NVIDIA GeForce RTX™ 2060

Issue description

The title is self-explanatory, but here's a screen capture code & motion artifacts as well:

Screencast.from.2023-04-14.14-37-44.webm

Steps to reproduce

Engine.time_scale = ts # where `ts != 1.0`
get_tree().paused = true

Through some experimentation I found that setting Engine.time_scale = 1.0 before setting get_tree().paused = true is a workaround for this edge case.

Minimal reproduction project

godot-4-dbg.zip

[MikeFrom]

when you want to pause (particle) shaders, I think you have to set Engine.time_scale = 0.0.

[Calinou]

• Duplicate of Particle jitter on low speed scale, when the SceneTree is paused or when process mode is Disabled due to interpolation #50824.