[Fall Guys island][Scene Graph] Fortnite crashes with a Scene Graph Entity with a custom rotator component when colliding with character

General Issues and Bug Reporting
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1

Please select what you are reporting on:

Unreal Editor for Fortnite

What Type of Bug are you experiencing?

Stability

Summary

Entity with a custom transform rotation component crashes when the Fall Guys character gets close enough to collide with it

Steps to Reproduce

Create a Fall Guys island
Enable Scene Graph
Create an entity
Add mesh component with default cube
Add collision component
Add the following custom component:

using { /Verse.org }
using { /Verse.org/Native }
using { /Verse.org/Simulation }
using { /UnrealEngine.com/Temporary/SpatialMath }
using { /UnrealEngine.com/Temporary/SceneGraph }

rotator_component<public> := class(component):
    @editable
    var RotationDegrees<public>:float = 10.0

    var TransformComp : ?transform_component = false

    var PrePhysicsCancelable : ?cancelable = false

    OnBeginSimulation<override>():void =
        (super:)OnBeginSimulation()
        if:
            Transform := Entity.GetComponent[transform_component]
        then:
            set TransformComp = option{Transform}
            set PrePhysicsCancelable = option{ TickEvents.PrePhysics.Subscribe(OnPrePhysics) }
        
    OnEndSimulation<override>():void=
        (super:)OnEndSimulation()
        option {PrePhysicsCancelable?.Cancel()}
        set PrePhysicsCancelable = false
    
    OnPrePhysics(DeltaTime:float):void=
        if:
            Transform := TransformComp?
        then:
            OriginalTransform := Transform.GetTransform()
            UpdatedRotation := OriginalTransform.Rotation.ApplyRoll(DegreesToRadians(RotationDegrees*DeltaTime))
            NewTransform := transform{Translation:=OriginalTransform.Translation, Rotation :=UpdatedRotation, Scale:=OriginalTransform.Scale}
            Transform.SetTransform(NewTransform)

    OnSimulate<override>()<suspends>:void={}
        
(Entity:entity).GetComponent<public>(component_type:subtype(component))<decides><transacts>:component_type=
    Entity.GetComponents(component_type)[0]

Place entity in the scene
Run Session
Start Game
Move character to where the component would collide with the character

Expected Result

The player should be able to stand in the rotating cube and collide normally, this issue is not present in regular fortnite islands this is the expected behavior

Observed Result

Fortnite crashes as soon as it is in collision range of the cube

Platform(s)

All

Additional Notes

crash log

2

I was thinking about it and came to a conclusion that this may be related to how the game calculates speed forces to be applied on beans on impacts:

In normal creative props and devices, we have anim_controller and MoveTo() to handle continuous movement across the scene… But, with scene graph, we only have SetTransform() wich is basically the same as TeleporTo[] wich is instant.

That can cause lots of problems depending on how the game handles the forces, if when calculating the prop move speed, it will take MoveSpeed = DistanceTravelled / MovementTime, and since TeleportTo is instant, can make the values absurdly big, almost nearly infinite if the time considered is a single frame, or if the game considers it as a zero value, that turns into a division by zero problem and maybe be the reason why the game is crashing.