PhotonDust - new particle system testing - Phase 1 (stability)

[Frooxius]

Hello everyone!

The time has finally come! Our new in-house particle system PhotonDust is ready to start testing! This testing is divided into two phases:

• Phase 1 - stability testing
• Phase 2 - compatibility testing

This testing is for Phase 1

Build Version

2024.12.5.1194

What is being tested

As part of our performance optimizations, we are replacing the existing (now called "Legacy") particle system in Resonite with our custom one called PhotonDust.

The legacy particle system is a hybrid between Unity and FrooxEngine, with Unity handling most of the simulation. This tight integration prevents moving FrooxEngine from being moved out of Unity into a more performant .NET 9 process. PhotonDust solves this problem, by handling most parts of the simulation completely within FrooxEngine and only submitting simulated results to Unity for rendering.

Since this introduces a new complex system to Resonite, this has potential to cause stability issues (though most were eliminated during development itself) and content compatibility issues - our system works on different principles from the original particle system - it is a lot more modular and flexible. This requires adapters to support existing content.

You can learn a bit more about PhotonDust here:
#587

General testing notes

• The new particle system is called just "Particle System"
• The old particle system is now called "Legacy Particle System"
• During testing, any existing content will keep using the old "Legacy Particle System" by default
• You can create new instances of PhotonDust as well as the old particle system - both systems exist independently in these builds

Converting old content

NOTE: While this is already implemented, it's not focus of Phase 1. Only use this to test variety of content for stability purposes.

• You can turn on conversion of old content in the Settings -> Misc -> Debug -> Convert particle system to PhotonDust
• After this setting is enabled, any legacy particle systems on items loaded inventory items, avatars & worlds by you will be converted to PhotonDust
• The setting doesn't affect items and worlds loaded by other users

Avoiding data corruption

• DO NOT save any converted worlds/items for any purpose other than testing - they might break or have conversion issues!
• DO NOT build any long term content with PhotonDust yet - there might be breaking changes during testing and your content will break

How to test

In the Phase 1 the main focus is stability of this new system and making sure it doesn't cause crashes and other negative issues just existing alongside the legacy particle system. I expect this phase to be shorter than the second one.

• On Steam, switch to the prerelease branch and make sure the build updates before you run it
• Make sure your build version matches the one at the top of this message

What to test

• Create new instances of the new particle system and mess around with them
• Try different modules and settings (trails, lights, billboard & mesh particles...)
• Delete the instances and modules
• Load content with legacy particle system without conversion enabled - the classes and other types were renamed, we we want to check if this broke anything
• Convert existing items and mess with them - DO NOT test conversion errors yet, only use this to test variety of content for stability purposes

What to watch out for

These are good things to watch out for when testing the new particle system:

• Sessions crashing
• Client crashing
• Freezing or locking up
• Severe performance drop with typical setups (meaning if you make a >million particles then performance drop is somewhat expected and probably shouldn't report that)

What NOT to test & report

• Generally things that do not involve this system - any existing unrelated bugs with components and other systems.
  -- If you're unsure, try to replicate the issue on the main build and see if it also occurs - if it also happens there, just report it as normal bug
• Feature parity of PhotonDust with Legacy Particle System - this is for phase 2
• Conversion issues of legacy content to PhotonDust - this is also for phase 2

If you find something that got broken

• Create a GitHub issue for a pre-release bug: https://github.com/Yellow-Dog-Man/Resonite-Issues/issues/new?assignees=shiftyscales&labels=prerelease&projects=&template=prerelease.yml
• Make sure to include the log
• Please include description of what happened. Be succinct, but exact.

If you find that stuff works okay

Please report it too and include details on what you generally tested, so we know things are okay. You don't need to make a new issue for this - just a comment in this Discussion is fine.

This lets us know that a bunch of stuff was tested and get better confidence that stuff won't break with release.

How long will testing go for?

I expect this phase to be relatively short (a few days maybe) as severe stability issues tend to show up pretty quickly.

Once I get feeling that things are good, we'll move to phase 2.

What to expect from Phase 2

To give you general overview what to expect from the next phase after this:

• Once I'm reasonably confident in the stability of the new system, we'll move to Phase 2
• PhotonDust will be pushed to main builds and will exist alongside Legacy Particle System
• Conversion will happen only optionally via the Setting
• Testing focus will be on making sure that conversion works correctly and existing content looks similar
• Once we're confident we have good compatibility with old content, the legacy particle system will be removed completely and conversion will be made automatic

[Frooxius]

New prerelease update has been released!

This is now out of date! See latest builds below!

2024.12.5.546 [PRE-RELEASE]
An update to the prerelease branch addressing some issues that were found with PhotonDust so far!

New Features:

• Added ability to support multiple modules of the same internal type
  -- This fixes crashes when moving or adding multiple modules (reported by @RockstarRaccoon, @epicEaston197, @decoybird , @orange3134, @Zozokasu, @RueShejn and @ModernBalloonie, issues Photon Dust - Adding two of the same Initliaizers to a ParticleStyle crashes world #3265, [Photon Dust] Adding a Module of a kind that is already on the Particle Style crashes the editor from the world, even if it's a replacement. #3264, Photon Dust - Moving a component world crash #3261, Photon Dust - Moving a Module component attached to a ParticleStyle component causes crash. #3268)
  -- Certain modules will only have the first instance in the list functional - notably PositionSimulator, RotationSimulator and OrientByVelocity
  -- Most modules can have multiple instances - generally if they affect the same properties, their effects are multiplicative
• Added Center property to RadialForce & OverrideForceSpace to allow determining in what space are the Center & Force defined

Fixes:

• Implement handling of disabled/inactive state for particle systems (reported by @moonbase__, issue [PhotonDust] Disabling A Slot That Has A ParticleSystem Component Doesn't Unrender Particles #3260)
• Fixed RadialForce not following the inverse square law

[Frooxius]

New prerelease update!

2024.12.5.1194 [PRE-RELEASE]
Another set of fixes for PhotonDust in the prerelease branch! Since it seems relatively quiet on stability issues and they're mostly fixed pretty quick, I'll probably open up Phase 2 of testing later today - first in the prerelease branch so we can start getting initial reports and then merge it in starting next week - keep a lookout for an announcement on this!

THIS BUILD IS IF TESTING PURPOSES ONLY! If you'd like to help test, please read the instructions here: #3259

Fixes:

• Fixed AngularVelocity initializer modules breaking particle system if they're added before the Rotation module is initialized (reported by @orange3134, issue Adding AngularVelocityInitializer will cause particles to stop working #3272)
• Fixed Speed initializer modules breaking particle system if they're added before PositionSimulator module is initialized (reported by @Nytra, issue Adding SpeedRangeInitializer module without a PositionSimulator module already present breaks the Particle System #3269)
• Fixed particle system with no active modules breaking (based on report by @mirpasec, issue Configure particle systems in a specific order, the new particle systems will not work. #3271)

[Frooxius]

Hello everyone!

Since the bug reports from this phase are relatively minor and have all been fixed up so far, I'm closing the Phase 1 and opening Phase 2, which means you can now start reporting compatibility issues!

Before you do so, please check out the Phase 2 post, specifically the instructions on how to report compatibility problems:
#3276

I'm closing this one now, please continue in the Phase 2 discussion! Thanks everyone for testing so far!