SpawnActor stuff

src/Prospect.Unreal/Core/Math/FTransform.cs

@@ -1,6 +1,6 @@
 namespace Prospect.Unreal.Core.Math;
 
-public ref struct FTransform
+public class FTransform
 {
     public FVector Location { get; set; }
     public FRotator Rotation { get; set; }

src/Prospect.Unreal/Core/Objects/FObjectInstancingGraph.cs

@@ -0,0 +1,6 @@
+namespace Prospect.Unreal.Core.Objects;
+
+public struct FObjectInstancingGraph
+{
+    
+}

src/Prospect.Unreal/Core/Objects/GUClassArray.cs

@@ -13,6 +13,6 @@ public class GUClassArray
     public static UClass StaticClass(Type type)
     {
         // TODO: Implement
-        return new UClass();
+        return new UClass(type);
     }
 }

src/Prospect.Unreal/Core/Objects/UClass.cs

@@ -4,5 +4,30 @@ namespace Prospect.Unreal.Core.Objects;
 
 public class UClass : UStruct
 {
+    public UClass(Type type)
+    {
+        Type = type;
+    }
     
+    public Type Type { get; }
+    
+    public UObject GetDefaultObject<T>() where T : UObject
+    {
+        // TODO: Implement
+        var obj = (UObject) Activator.CreateInstance<T>();
+        
+        obj.SetFlags(EObjectFlags.RF_Public | EObjectFlags.RF_ClassDefaultObject | EObjectFlags.RF_ArchetypeObject);
+        
+        return obj;
+    }
+
+    public UObject GetDefaultObject(bool bCreateIfNeeded = true)
+    {
+        throw new NotImplementedException();
+    }
+
+    public UObject CreateDefaultObject()
+    {
+        throw new NotImplementedException();
+    }
 }

src/Prospect.Unreal/Core/Objects/UObject.cs

@@ -2,5 +2,9 @@
 
 public class UObject : UObjectBaseUtility
 {
-    
+    public bool CheckDefaultSubobjects(bool bForceCheck = false)
+    {
+        // TODO: Implement
+        return true;
+    }
 }

src/Prospect.Unreal/Core/Objects/UObjectBaseUtility.cs

@@ -40,6 +40,12 @@ public class UObjectBaseUtility : UObjectBase
         return false;
     }
 
+    public bool IsPendingKill()
+    {
+        // TODO: GUObjectArray
+        return false;
+    }
+    
     /*
      * Outer & Package
      */

src/Prospect.Unreal/Core/Objects/UObjectGlobals.cs

@@ -0,0 +1,34 @@
+using Prospect.Unreal.Core.Names;
+using Prospect.Unreal.Exceptions;
+
+namespace Prospect.Unreal.Core.Objects;
+
+public class UObjectGlobals
+{
+    public static T? NewObject<T>(UObject outer,
+        UClass clazz,
+        FName? name = null,
+        EObjectFlags flags = EObjectFlags.RF_NoFlags,
+        UObject? template = null,
+        bool bCopyTransientsFromClassDefaults = false,
+        FObjectInstancingGraph? inInstanceGraph = null,
+        UPackage? externalPackage = null)
+    {
+        if (name == null)
+        {
+            name = EName.None;
+        }
+        
+        // NewObject
+        // StaticConstructObject_Internal
+        // StaticAllocateObject
+
+        var obj = Activator.CreateInstance(clazz.Type);
+        if (obj == null)
+        {
+            throw new UnrealException("Failed to create object.");
+        }
+
+        return (T?) obj;
+    }
+}

src/Prospect.Unreal/Net/Actors/AActor.cs

@@ -1,4 +1,5 @@
 using Prospect.Unreal.Core;
+using Prospect.Unreal.Core.Math;
 using Prospect.Unreal.Core.Objects;
 using Prospect.Unreal.Runtime;
 
@@ -7,6 +8,7 @@ namespace Prospect.Unreal.Net.Actors;
 public class AActor : UObject
 {
     private bool bActorInitialized;
+    private bool bActorIsBeingDestroyed;
     
     // TODO: UPROPERTY(BlueprintReadWrite, ReplicatedUsing=OnRep_Instigator, meta=(ExposeOnSpawn=true, AllowPrivateAccess=true), Category=Actor)
     /// <summary>
@@ -14,6 +16,12 @@ public class AActor : UObject
     /// </summary>
     private APawn? _instigator;
     
+    // TODO: UPROPERTY(EditAnywhere, BlueprintReadWrite, Category=Actor)
+    /// <summary>
+    ///     Controls how to handle spawning this actor in a situation where it's colliding with something else. "Default" means AlwaysSpawn here.
+    /// </summary>
+    public ESpawnActorCollisionHandlingMethod SpawnCollisionHandlingMethod { get; set; }
+    
     /// <summary>
     ///     Sets the value of Role without causing other side effects to this instance.
     /// </summary>
@@ -81,4 +89,22 @@ public class AActor : UObject
     {
         return bActorInitialized;
     }
+
+    public bool IsPendingKillPending()
+    {
+        return bActorIsBeingDestroyed || IsPendingKill();
+    }
+
+    public void PostSpawnInitialize(FTransform userSpawnTransform, AActor? inOwner, AActor? inInstigator, bool bRemoteOwned, bool bNoFail, bool bDeferConstruction)
+    {
+        // General flow here is like so
+        // - Actor sets up the basics.
+        // - Actor gets PreInitializeComponents()
+        // - Actor constructs itself, after which its components should be fully assembled
+        // - Actor components get OnComponentCreated
+        // - Actor components get InitializeComponent
+        // - Actor gets PostInitializeComponents() once everything is set up
+        //
+        // This should be the same sequence for deferred or nondeferred spawning.
+    }
 }

src/Prospect.Unreal/Net/UNetDriver.cs

@@ -2,6 +2,7 @@
 using System.Net;
 using Prospect.Unreal.Core.Names;
 using Prospect.Unreal.Exceptions;
+using Prospect.Unreal.Net.Actors;
 using Prospect.Unreal.Net.Channels;
 using Prospect.Unreal.Net.Channels.Actor;
 using Prospect.Unreal.Net.Channels.Control;
@@ -269,6 +270,29 @@ public abstract class UNetDriver : IAsyncDisposable
         };
     }
 
+    public void AddNetworkActor(AActor actor)
+    {
+        // if (!IsDormInitialStartupActor(Actor))
+        // {
+        //     GetNetworkObjectList().FindOrAdd(Actor, this);
+        //     if (ReplicationDriver)
+        //     {
+        //         ReplicationDriver->AddNetworkActor(Actor);
+        //     }
+        // }
+    }
+
+    public void RemoveNetworkActor(AActor actor)
+    {
+        // Remove from renamed list if destroyed
+        // RenamedStartupActors.Remove(Actor->GetFName());
+        //
+        // if (ReplicationDriver)
+        // {
+        //     ReplicationDriver->RemoveNetworkActor(Actor);
+        // }
+    }
+
     public virtual ValueTask DisposeAsync()
     {
         return ValueTask.CompletedTask;

src/Prospect.Unreal/Runtime/UWorld.LevelActor.cs

@@ -1,7 +1,9 @@
 using System.Text;
 using Prospect.Unreal.Core;
 using Prospect.Unreal.Core.Math;
+using Prospect.Unreal.Core.Names;
 using Prospect.Unreal.Core.Objects;
+using Prospect.Unreal.Exceptions;
 using Prospect.Unreal.Net;
 using Prospect.Unreal.Net.Actors;
 
@@ -63,7 +65,7 @@ public partial class UWorld
         return SpawnActor(clazz, transform, spawnParameters);
     }
 
-    public AActor SpawnActor(UClass? clazz, FTransform userTransform, FActorSpawnParameters spawnParameters)
+    public AActor SpawnActor(UClass? clazz, FTransform? userTransformPtr, FActorSpawnParameters spawnParameters)
     {
         if (clazz == null)
         {
@@ -84,10 +86,91 @@ public partial class UWorld
 
         if (template == null)
         {
-            // template = clazz.GetDefaultObject();
+            template = (AActor)clazz.GetDefaultObject<AActor>();
         }
 
-        return null;
+        if (newActorName == EName.None)
+        {
+            // If we are using a template object and haven't specified a name, create a name relative to the template, otherwise let the default object naming behavior in Stat
+            if (!template.HasAnyFlags(EObjectFlags.RF_ClassDefaultObject))
+            {
+                throw new NotImplementedException();
+            }
+        } 
+        /* else if (StaticFindObjectFast(nullptr, LevelToSpawnIn, NewActorName)) */
+
+        // See if we can spawn on ded.server/client only etc (check NeedsLoadForClient & NeedsLoadForServer)
+        // TODO: CanCreateInCurrentContext
+
+        var userTransform = userTransformPtr ?? new FTransform(); // TODO: FTransform::Identity
+        var collisionHandlingOverride = spawnParameters.SpawnCollisionHandlingOverride;
+        
+        // "no fail" take preedence over collision handling settings that include fails
+        if (spawnParameters.bNoFail)
+        {
+            // maybe upgrade to disallow fail
+            if (collisionHandlingOverride == ESpawnActorCollisionHandlingMethod.AdjustIfPossibleButDontSpawnIfColliding)
+            {
+                collisionHandlingOverride = ESpawnActorCollisionHandlingMethod.AdjustIfPossibleButAlwaysSpawn;
+            } 
+            else if (collisionHandlingOverride == ESpawnActorCollisionHandlingMethod.DontSpawnIfColliding)
+            {
+                collisionHandlingOverride = ESpawnActorCollisionHandlingMethod.AlwaysSpawn;
+            }
+        }
+
+        // use override if set, else fall back to actor's preference
+        var collisionHandlingMethod = (collisionHandlingOverride == ESpawnActorCollisionHandlingMethod.Undefined)
+            ? template.SpawnCollisionHandlingMethod
+            : collisionHandlingOverride;
+        
+        // see if we can avoid spawning altogether by checking native components
+        // note: we can't handle all cases here, since we don't know the full component hierarchy until after the actor is spawned
+        if (collisionHandlingMethod == ESpawnActorCollisionHandlingMethod.DontSpawnIfColliding)
+        {
+            throw new NotImplementedException();
+        }
+
+        var actorFlags = spawnParameters.ObjectFlags;
+        UPackage? externalPackage = null;
+        
+        // actually make the actor object
+        var actor = UObjectGlobals.NewObject<AActor>(levelToSpawnIn, clazz, newActorName, actorFlags, template, false, null, externalPackage);
+
+        if (actor == null)
+        {
+            throw new UnrealException("Failed to create actor");
+        }
+
+        if (actor.GetLevel() != levelToSpawnIn)
+        {
+            throw new UnrealException("Actor spawned with the incorrect level");
+        }
+        
+        // tell the actor what method to use, in case it was overridden
+        actor.SpawnCollisionHandlingMethod = collisionHandlingMethod;
+        
+        actor.PostSpawnInitialize(userTransform, spawnParameters.Owner, spawnParameters.Instigator, spawnParameters.bRemoteOwned, spawnParameters.bNoFail, spawnParameters.bDeferConstruction);
+        
+        // if we are spawning an external actor, clear the dirty flag after post spawn initialize which might have dirtied the level package through running construction scripts
+        if (externalPackage != null)
+        {
+            throw new NotImplementedException();
+        }
+
+        if (actor.IsPendingKill() && !spawnParameters.bNoFail)
+        {
+            // TODO: GetPathName
+            Logger.Debug("SpawnActor failed because the spawned actor %s IsPendingKill");
+            return null;
+        }
+
+        actor.CheckDefaultSubobjects();
+        
+        // Add this newly spawned actor to the network actor list. Do this after PostSpawnInitialize so that actor has "finished" spawning.
+        AddNetworkActor(actor);
+        
+        return actor;
     }
 
     public T SpawnActor<T>(UClass? clazz, FActorSpawnParameters spawnParameters) where T : AActor

src/Prospect.Unreal/Runtime/UWorld.cs

@@ -34,6 +34,8 @@ public abstract partial class UWorld : FNetworkNotify, IAsyncDisposable
         _owningGameInstance = null;
         _authorityGameMode = null;
         _levels = new List<ULevel>();
+
+        Url = new FUrl();
     }
     
     /// <summary>
@@ -64,7 +66,7 @@ public abstract partial class UWorld : FNetworkNotify, IAsyncDisposable
     /// <summary>
     ///     The URL that was used when loading this World.
     /// </summary>
-    public FUrl? Url { get; private set; }
+    public FUrl Url { get; private set; }
     
     /// <summary>
     ///     Time in seconds since level began play, but IS paused when the game is paused, and IS dilated/clamped.
@@ -156,7 +158,7 @@ public abstract partial class UWorld : FNetworkNotify, IAsyncDisposable
         var options = inUrl.OptionsToString();
 
         // Set level info.
-        if (!string.IsNullOrEmpty(inUrl.GetOption("load", null)))
+        if (string.IsNullOrEmpty(inUrl.GetOption("load", null)))
         {
             Url = inUrl;
         }
@@ -446,6 +448,49 @@ public abstract partial class UWorld : FNetworkNotify, IAsyncDisposable
         connection.SetClientLoginState(EClientLoginState.Welcomed);
     }
 
+    private void AddNetworkActor(AActor? actor)
+    {
+        if (actor == null)
+        {
+            Logger.Verbose("Failed to add actor, null");
+            return;
+        }
+
+        if (actor.IsPendingKillPending())
+        {
+            Logger.Verbose("Failed to add actor, IsPendingKillPending");
+            return;
+        }
+
+        var level = actor.GetLevel();
+        if (level == null || !ContainsLevel(level))
+        {
+            Logger.Verbose("Failed to add actor, world does not contain level");
+            return;
+        }
+
+        if (NetDriver != null)
+        {
+            NetDriver.AddNetworkActor(actor);
+        }
+    }
+
+    private void RemoveNetworkActor(AActor? actor)
+    {
+        if (actor != null)
+        {
+            if (NetDriver != null)
+            {
+                NetDriver.RemoveNetworkActor(actor);
+            }
+        }
+    }
+
+    private bool ContainsLevel(ULevel inLevel)
+    {
+        return _levels.Contains(inLevel);
+    }
+
     public bool IsServer()
     {
         if (NetDriver != null)