Unreal Engine Upgrades

DataConfig is committed to support multiple UE versions with no deprecations and warnings. On this page we'll document important upgrade and migration info.

UE5.7

  • FindObject series of functions deprecates bExactClass in favor of EFindObjectFlags.
  • Many metadata fields like BaseStruct, AllowedClasses requires full long names:
    • for example previously for instanced struct we can do this: UPROPERTY(EditAnywhere, meta = (BaseStruct = "DcStructShapeBase")). Now it has to be using the full path starting with / like UPROPERTY(EditAnywhere, meta = (BaseStruct = "/Script/DataConfigExtra.DcStructShapeBase")).
    • See the full list in LongPathNameMetaDataSpecifierValidator in UhtDefaultSpecifiers.cs.

UE5.6

  • FString::Appendf and series of functions now do compile time check on the format string, requires the format string to be a static constexpr.
  • GMalloc access is deprecated.
  • 'UClass::ClassDefaultObject' is deprecated in favor of global GetDefault<>() or GetMutableDefault<>().

UE5.5

  • A new series batch scripts named Engine/Build/BatchFiles/RunUBT are added which will will do a bunch of checks before running UnrealBuildTool. One should now use RunUBT instead of UnrealBuildTool otherwise it won't work in some configuration.
  • EAutomationTestFlags is now a enum class type.
  • TIsTriviallyDestructible is deprecated over std::is_trivially_destructible_v.
  • TFieldPath(OtherPropertyType*) constructor now checks for actual type safety.
  • FProperty::ElementSize deprecated over GetElementSize.
  • StructUtils plugin is deprecated with all things moved in engine.
  • PER_MODULE_BOILERPLATE not needed anymore as UBT handles it automatically.
  • FVerseValueProperty renamed to FVValueProperty, also compiled only with WITH_VERSE_VM define.

UE5.4

  • New property Optional and VValue are added. We fully support Optional starting by adding EDcDataEntry::OptionalRoot/OptionalEnd and then evantually it works with all DataConfig APIs including JSON/MsgPack serialization and property builder.
  • FObjectPtrProperty/FClassPtrProperty are deprecated. It's introduced in 5.0 now removed and alias to FObjectProperty/FClassProperty respectively.
  • Defaults to MSVC \W4 flag now which checks for unreachable code. It reports confusing locations and you can set bUseUnity = false in your *.Build.cs module rules to locate whereabout.
  • FText internal pointer changed from TSharedRef to TRefCountPtr.

UE5.3

  • Introduces BuildSettingsVersion.V4 which now defaults to C++ 20.
  • TRemoveConst is deprecated over std::remove_const.
  • FScriptDelegate etc now has additional checkers based on threading model and debug/release build. Thus we change how FScriptDelegateAccess works.

UE5.2

  • TIsSame is deprecated over std::is_same.
  • In Build.cs bEnforceIWYU is changed to enum IWYUSupport.

UE5.1

  • UE5.1 deprecates ANY_PACKAGE in favor of a new method FindFirstObject. In DataConfig we provided DcSerdeUtils::FindFirstObject which calls FindObject(ANY_PACKAGE) pre 5.1 and calls FindFirstObject() for 5.1 and onwards.

UE5.0

  • New TObjectPtr to replace raw UObject pointers. Turns out this is mostly handled within the engine and is transparent to DataConfig.

  • New property types FObjectPtrProperty and FClassPtrProperty are added. They're handled the same as FObjectProperty and FClassProperty respectively.

  • FVector now is 3 doubles, and Real data type in Blueprint now is also double. This is also mostly transparent to DataConfig.

  • FScriptArrayHelperAccess size changes with a added uint32 ElementAlignment.

  • TStringBuilderWithBuffer API changes. At call sites we now do Sb << TCHAR('\n') instead of Sb.Append(TCHAR('\n')) .

UE4

  • The oldest version DataConfig supports is UE 4.25, in which it introduces a major refactor that changes UProperty to FProperty. We intended to support UE4 in the foreseeable future, especially when we now have separated uplugin for UE4 and UE5.