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Knowledge base
Free, anonymous browsing of Unreal Engine Blueprint examples, node references, and best practices. The same content the WoalzCraft plugin uses to generate Blueprints.
24 results for Object Reference
Why: '{a}' includes '{b}' as a hard reference, AND '{b}' includes '{a}' as a hard reference. UE5 can't compile either one first without the other already being compiled. Fix: Break the cycle by making ONE side use a SOFT reference (TSoftObjectPtr). Pick the side that doesn't need {b} immediately at construction — change the variable type to 'Soft Object Reference' instead of 'Object Reference'. Use Load Asset to resolve it at runtime.
A pointer to a UObject instance. If the target is destroyed the reference becomes invalid — always IsValid-check before use.
Why: Your code reads from a '{ref}' reference, but nothing was assigned to it. UE5 doesn't error at compile time, but warns that the runtime access will crash with null-pointer. Fix: Wherever this BP spawns, set the reference via Spawn Actor From Class → Set Reference. If it should be set from outside, expose the variable (eye-icon = Instance Editable) so it's set in the level editor. Add an Is Valid? Branch before each read to gracefully handle null.
Returns null if asset not loaded. Use AsyncLoadAsset first, then resolve.
Conv_SoftObjectRefToObjectUE 5.3, 5.4, 5.5, 5.6, 5.7updated 2mo agoSafely converts an Object Reference to a more specific class. Branch on the Failed output — casting to the wrong class returns null.
IsValid is a MACRO with two exec outputs: 'Is Valid' and 'Is Not Valid'. NOT a pure bool function.
IsValidUE 5.3, 5.4, 5.5, 5.6, 5.7updated 2mo agoReturns True if an Object Reference points to a live (non-destroyed) UObject. Always IsValid-check references before use to avoid crashes.
UKismetSystemLibrary::IsValid. Also check IsValidMacro for exec-based branching (Is Valid + Branch combined).
IsValidUE 5.0, 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.7updated 2mo agoK2Node_DynamicCast. Cast Failed pin name is CastFailed. As output pin is dynamically named.
CastToUE 5.4, 5.7updated 2mo agoA reference to a class (not an instance). Use as input to SpawnActor or to compare types.