The World API

World is how a script reaches everything beyond its own entity. It has two parts, methods on the world itself, and subsystem properties that group related functionality.

Entity Pickup = World.SpawnPrefab("/Game/Content/Prefabs/Coin", new FVector3(0, 1, 0));
World.Physics.AddImpulse(Pickup, new FVector3(0, 5, 0));   // a subsystem

Subsystems

Each subsystem is a property on World.

Property	What it does
`World.Registry`	The component store, with `Get<T>`, `Emplace<T>`, views, signals. See Entities & Components.
`World.Physics`	Forces, velocities, raycasts, overlaps. See Physics.
`World.Navigation`	Pathfinding and agent movement over the navmesh.
`World.UI`	Screen-space RmlUi documents. See User Interface.
`World.Perception`	What AI entities can see and hear. See Perception.
`World.Messages`	The gameplay message bus. See Events.
`World.Tags`	The gameplay tag registry. See Gameplay Tags.
`World.Net`	Network role and replication state. See Networking.
`World.Draw`	Debug drawing (Development and Debug builds only).
`World.Input`	Poll actions, keys, and the mouse by name. See Input.
`World.Camera`	The active camera, screen projection, and camera shakes. See Cameras.
`World.Audio`	Playing and mixing sound. See Audio.
`World.Timers`	One-shot and looping timers. See Timers.
`World.Animation`	Clips, graph parameters, and montages. See Animation.

Entities

Call	Result
`World.CreateEntity(name, location?, rotation?, scale?)`	A new named entity with a transform and nothing else
`World.SpawnPrefab(path)`	Instantiates a prefab, returns its root `Entity`
`World.SpawnPrefab(path, location, rotation?, parent?)`	Same, placed (and optionally parented) in one call
`World.SpawnPrefab(path, transform, configure, parent?)`	Same, running `configure(root)` before the next frame so values are in place for `OnReady`
`World.SpawnProjectile(origin, velocity, damage?, lifetime?)`	Fires a swept projectile entity (see Projectiles)
`World.DuplicateEntity(entity)`	Deep-copies an entity and its children, returns the new root
`World.DestroyEntity(entity)`	Removes the entity
`World.SetLifetime(entity, seconds)`	Destroys it after a delay; calling again retimes the countdown
`World.IsValidEntity(entity)`	`false` once it has been destroyed and its id recycled
`World.GetEntityByName(name)`	First entity with that name (`Entity.Null` if none)
`World.FindByTag(tag)`	First entity with that tag (`GetEntityByTag` is the same call)
`World.FindAllByTag(tag)`	Every entity with that tag, as a fresh `List<Entity>`
`World.EntityHasTag(entity, tag)`	`bool`
`World.GetEntityName(entity)`	The entity’s name
`World.GetNumEntities()`	Count of live entities

Every SpawnPrefab overload also takes a TSoftObjectPtr<CPrefab> or an FSoftObjectPath instead of a path string, so a prefab authored as a [Property] reference spawns without unwrapping it first.

[Property] public TSoftObjectPtr<CPrefab> EnemyPrefab;

Entity Enemy = World.SpawnPrefab(EnemyPrefab, Where, Configure: E =>
{
    Registry.GetScript<Enemy>(E)!.Health = 50.0f;
});

Entity Player = World.GetEntityByName("Player");
if (!Player.IsNull)
{
    World.SetEntityRotation(Player, FQuat.Identity);
}

World.CreateEntity makes a bare entity you build up with World.Registry.Emplace<T>(entity). A world system has the same pair on its context as Create() / Destroy(entity).

Transform (world space)

Call	Result
`World.GetEntityLocation(entity)` / `World.SetEntityLocation(entity, v)`	`FVector3`
`World.SetEntityRotation(entity, q)`	sets rotation
`World.TranslateEntity(entity, delta)`	moves by a world-space delta

For several operations on one entity in a single callback, resolve its STransformComponent once with World.Registry.Get<STransformComponent>(entity) and call its methods directly. Do not keep that wrapper past the callback: it points into registry storage that any structural change can move, so re-resolve it next frame, exactly as Transform does.

Hierarchy

Call	Result
`World.SetParent(child, parent)`	Reparents `child` (preserving world transform)
`World.DetachFromParent(entity)`	Detaches to the world root
`World.GetParent(entity)`	The parent, or `Entity.Null`
`World.GetRootEntity(entity)`	The top of the entity’s tree

Time

Call	Returns
`World.DeltaTime`	Seconds since the last frame
`World.ElapsedTime`	Seconds since the world was created
`World.Paused`	Get or set. Pauses systems, scripts, and physics; the UI keeps running, so a pause menu can set it back
`World.TimeDilation`	Get or set. Below 1 is slow motion, above 1 speeds the world up. Clamped to 0 or greater

OnUpdate already receives DeltaTime as its argument; World.DeltaTime is there for code reached outside a hook.

Components and scripts on other entities

Anything you can do to your own entity’s components, you can do to another’s through World.Registry, passing that entity.

Entity Door = World.GetEntityByName("Door");
SStaticMeshComponent Mesh = World.Registry.Get<SStaticMeshComponent>(Door);

To call into another entity’s script, fetch its instance by type.

Health? H = World.Registry.GetScript<Health>(Door);
H?.ApplyDamage(10);

GetScript<T> returns the live managed instance (or null), so you call its public methods directly, with no marshalling. See Events for decoupled communication that doesn’t need a direct reference.

Debug drawing

World.Draw draws shapes for tuning and visualization. The draws are no-ops in Shipping builds, and a Duration of 0 draws for a single frame.

FVector4 Red = new FVector4(1, 0, 0, 1);
World.Draw.Sphere(Transform.GetWorldLocation(), 0.5f, Red);
World.Draw.Line(a, b, Red, Thickness: 2.0f, Duration: 1.0f);

The World.Draw methods are Line, Sphere, Box, and Text (screen-space).