Severe FPS drop down to < 1 FPS / lag at high time warp due to launch particle FX scaling with simulation speed

[Maxi]

Game Version​

2026.5.12.4510

Operating System​

Windows 10

What Happened​

Increasing time warp while controlling a vehicle in flight causes a severe, progressively worsening frame-rate collapse down to < 1 FPS.

The slowdown scales with the selected simulation speed: it is already noticeable a few warp steps up and becomes near-unresponsive at high warp (e.g. x86400).
It happens during normal flight and in orbit, with or without a maneuver planned, and also occurs when auto/warp-to ramps the speed up on its own (e.g. after the transfer planner planned an LEO -> Mars burn).

It is important that this only happens if the ice particles have still not fallen of the Rocket. E.g. You spawn the Rocket in Orbit -> The Ice Particles introduced in 2026.5.12.4510 have not fallen of yet because the rocket engine was never active -> timewarp to first burn is the issue.

What Was Expected​

High time warp should stay smooth and performant, as it did in the previous build (2026.5.11.4462). Raising the simulation speed should not scale per-frame CPU work without bound.

Reproduction Steps​

1. Disable all mods so only Core is enabled.
2. Launch or load a vehicle that has cryogenic propellant tanks (e.g. the default Rocket).
3. Increase time warp.
4. Observe the frame rate collapse; the slowdown gets worse the higher the simulation speed.

Reproduction Rate​

Always (whenever a moving vehicle with cryogenic tanks - where the ice particles have not fallen off yet - is at elevated warp).

Possible Root Cause​

A new method Vehicle.TrySpawnLaunchParticles() (cryogenic-tank frost / ice / insulation-debris FX, called from Vehicle.SpawnParticles() every frame) spawns particles in loops bounded by "1.0 * Universe.SimulationSpeed" and "5.0 * Universe.SimulationSpeed".

The per-spawn random throttle "Random > Math.Min(1, 0.3636 * SimulationSpeed)" saturates at a simulation speed of about x2.75, so above ~x3 every loop iteration performs full emitter work AND the iteration count grows linearly with warp (about 432,000 iterations per affected tank per frame at x86400).

This method did not exist in previous versions such as 2026.5.11.4462 since the ice particles just got added in this version.

Additional Info​

• Hardware:
  • Processor AMD Ryzen 7 1800X Eight-Core Processor 3.60 GHz
  • Installed RAM 32,0 GB
  • Graphics Card NVIDIA GeForce RTX 2080 Ti (11 GB)