#TREE IT UE4 SERIES#

IsValid() could crash the game it might be a dangling pointer because it wasn't explicitly set to nullptr. Pointers that aren't marked with UPROPERTY() are not exposed to the reflection system, thus won't explicitly be set to nullptr when the address is no longer valid.

Garbage collection reliance is the tradeoff made for attaining an easy scripting experience, as the allocated memory gets handled automatically and intelligently.

Using TWeakPtr for classes derived from FGCObject works well, while using TSharedPtr creates tricky situations.

These nodes can't simultaneously participate in Unreal's separate memory tracking system geared for game-code, thus would preferably not be UObjects or classes derived from FGCObject.

TSharedPtr is excellent for managing the lifetime of tree-like nodes.

Again, not really related to tangible gameplay mechanics, or a part of the entire surface-level Player Controller, Player State, Pawn, etc. Let's not forget mentioning TSharedFromThis, which is the class many classes derive from to directly get an instance as TSharedRef. You'd also see TWeakPtr being used on FGCObjects once in a while. Those nodes are stored as TSharedPtr, which reminds me of how std::shared_ptr is commonly used for creating tree-like relationships.ДЄfter all, lots of back-end modules make use of TSharedPtr and TWeakPtr for doing all kinds of non-gameplay related things. The primary way UGameplayTagManager stores and retrieves gameplay tags is by storing them as nodes in a tree-like fashion, parallel to how gameplay tag strings maintain hierarchy with dot delimiters. More ways the engine uses TWeakPtr or TSharedPtr TScriptDelegate stores the object bound to the delegate as FWeakObjectPtr, which makes a lot of sense if you think about how you would logically expect the ownership to be handled. The macros that declare a dynamic delegate create a class that inherits from TBaseDynamicDelegate, which inherits from TScriptDelegate. (It actually uses the non-generic FWeakObjectPtr, which implies UObject only.)

#TREE IT UE4 SERIES#

Most likely as an observer, while not 'telling the engine it should not be GC'ed because your UPROPERTY() marked field is storing the address.'ДЄ great example of where TWeakObjectPtr shines is its usage by the series of DECLARE_DYNAMIC_ delegate variants. It's a great way to add detail on how you're using it. TWeakObjectPtr doesn't prevent GC and becomes NULL when the underlying object is destroyed. TSharedPtr, TSharedRef, TWeakPtr, TUniquePtr Drawing the line Not compatible with UObject Your might have heard the story about how using Unreal's smart pointers ( TSharedPtr, TSharedRef, TWeakPtr, TUniquePtr) causes unexpected results on UObjects, because the UObject memory management system is geared for game code, which is much more garbage collection oriented.ДЄ clear distinction between what is exposed to the uobject memory management system and what not must not be foreign. How does Unreal's smart pointer library work with UObjects? Let's establish a clear distinction.

Tree it ue4