Initial commit: Item Interaction Ecosystem plugin (UE5.7)

Server-authoritative, data-driven item/inventory/interaction/carry/equipment/
world-slot/placement/crafting framework. 8 modules, compiles against UE 5.7.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Source/ItemWorld/Public/PickupItemActor.h

@@ -0,0 +1,82 @@
+// Copyright ExByte Studios. Item Interaction Ecosystem.
+
+#pragma once
+
+#include "CoreMinimal.h"
+#include "GameFramework/Actor.h"
+#include "ItemInstanceData.h"
+#include "ItemInteractionInterfaces.h"
+#include "PickupItemActor.generated.h"
+
+class UStaticMeshComponent;
+class UInteractableComponent;
+
+/**
+ * The world representation of an item lying on the ground / a surface (section 12).
+ *
+ * One actor per world item only (never one per inventory item - section 32/34).
+ * Implements IWorldItemProvider so the interaction layer can pick it up, carry it
+ * or take part of its stack without ItemWorld <-> ItemInteraction coupling.
+ */
+UCLASS()
+class ITEMWORLD_API APickupItemActor : public AActor, public IWorldItemProvider
+{
+	GENERATED_BODY()
+
+public:
+	APickupItemActor();
+
+	virtual void GetLifetimeReplicatedProps(TArray<FLifetimeProperty>& OutLifetimeProps) const override;
+	virtual void BeginPlay() override;
+
+	/** Server: stamp this pickup with an item and refresh its visuals. */
+	UFUNCTION(BlueprintCallable, Category = "Item|World")
+	void InitializeFromItem(const FItemInstanceData& InItem);
+
+	/** Server convenience: spawn a fresh pickup for ItemId at a transform. */
+	UFUNCTION(BlueprintCallable, Category = "Item|World", meta = (WorldContext = "WorldContext"))
+	static APickupItemActor* SpawnPickup(UObject* WorldContext, FName ItemId, int32 Quantity, const FTransform& Transform);
+
+	/** Server convenience: spawn a pickup carrying an existing instance (e.g. on drop). */
+	static APickupItemActor* SpawnPickupFromInstance(UObject* WorldContext, const FItemInstanceData& Item, const FTransform& Transform);
+
+	//~ IWorldItemProvider
+	virtual bool GetProvidedItem(FItemInstanceData& OutItem) const override;
+	virtual bool IsItemAvailable() const override;
+	virtual void NotifyItemTaken(AActor* Taker) override;
+	virtual void UpdateProvidedItem(const FItemInstanceData& RemainingItem) override;
+	virtual void SetCarried(AActor* Holder, bool bCarried) override;
+
+	/** Server: drop this carried actor back into the world at a transform. */
+	void ReleaseToWorld(const FTransform& WorldTransform);
+
+	UStaticMeshComponent* GetMeshComponent() const { return Mesh; }
+
+	UFUNCTION(BlueprintPure, Category = "Item|World")
+	const FItemInstanceData& GetItemData() const { return ItemData; }
+
+protected:
+	UPROPERTY(VisibleAnywhere, BlueprintReadOnly, Category = "Item|World")
+	TObjectPtr<USceneComponent> Root;
+
+	UPROPERTY(VisibleAnywhere, BlueprintReadOnly, Category = "Item|World")
+	TObjectPtr<UStaticMeshComponent> Mesh;
+
+	UPROPERTY(VisibleAnywhere, BlueprintReadOnly, Category = "Item|World")
+	TObjectPtr<UInteractableComponent> Interactable;
+
+	UPROPERTY(ReplicatedUsing = OnRep_ItemData, BlueprintReadOnly, Category = "Item|World")
+	FItemInstanceData ItemData;
+
+	UPROPERTY(Replicated, BlueprintReadOnly, Category = "Item|World")
+	bool bIsLocked = false;
+
+	UPROPERTY(Replicated, BlueprintReadOnly, Category = "Item|World")
+	TObjectPtr<AActor> CurrentHolder = nullptr;
+
+	UFUNCTION()
+	void OnRep_ItemData();
+
+	/** Resolves the definition and applies WorldMesh + interactable display name. */
+	void RefreshVisuals();
+};