file
function     struct BLUEPRINTGRAPH_API FBlueprintMetadata { public: // Struct/Enum/Class: // If true, this class, struct, or enum is a valid type for use as a variable in a blueprint static const FName MD_Allow

	static const FName MD_RestrictedToClasses;

	/// [ClassMetadata] Used for Actor and Component classes. If the native class cannot tick, Blueprint generated classes based this Actor or Component can have bCanEverTick flag overridden even if bCanBlueprintsTickByDefault is false.
	static const FName MD_ChildCanTick;

	/// [ClassMetadata] Used for Actor and Component classes. If the native class cannot tick, Blueprint generated classes based this Actor or Component can never tick even if bCanBlueprintsTickByDefault is true.
	static const FName MD_ChildCannotTick;

	/// [ClassMetadata] Used to make the first subclass of a class ignore all inherited showCategories and hideCategories commands
	static const FName MD_IgnoreCategoryKeywordsInSubclasses;

	/** Specifies which struct implements the custom thunk functions for this class */

file
function     void FKismetCompilerContext::SetCanEverTick

			const UEngine* EngineSettings = GetDefault<UEngine>();
			const bool bAllowTickingByDefault = EngineSettings->bCanBlueprintsTickByDefault;

			const UClass* FirstNativeClass = FBlueprintEditorUtils::FindFirstNativeClass(NewClass);
			const bool bHasCanTickMetadata = (FirstNativeClass != nullptr) && FirstNativeClass->HasMetaData(FBlueprintMetadata::MD_ChildCanTick);
			const bool bHasCannotTickMetadata = (FirstNativeClass != nullptr) && FirstNativeClass->HasMetaData(FBlueprintMetadata::MD_ChildCannotTick);
			const bool bHasUniversalParent = (FirstNativeClass != nullptr) && ((AActor::StaticClass() == FirstNativeClass) || (UActorComponent::StaticClass() == FirstNativeClass));

file
function     void UEditorEngine::PostEditChangeProperty

		FBlueprintCoreDelegates::SetScriptMaximumLoopIterations( MaximumLoopIterationCount );
	}
	else if (PropertyName == GET_MEMBER_NAME_CHECKED(UEngine, bCanBlueprintsTickByDefault))
	{
		FScopedSlowTask SlowTask(100, LOCTEXT("DirtyingBlueprintsDueToTickChange", "InvalidatingAllBlueprints"));

		// Flag all Blueprints as out of date (this doesn't dirty the package as needs saving but will force a recompile during PIE)
		for (TObjectIterator<UBlueprint> BlueprintIt; BlueprintIt; ++BlueprintIt)
		{

file
namespace    UM

		BlueprintSpawnableComponent,

		/// [ClassMetadata] Used for Actor and Component classes. If the native class cannot tick, Blueprint generated classes based this Actor or Component can have bCanEverTick flag overridden even if bCanBlueprintsTickByDefault is false.
		ChildCanTick,

		/// [ClassMetadata] Used for Actor and Component classes. If the native class cannot tick, Blueprint generated classes based this Actor or Component can never tick even if bCanBlueprintsTickByDefault is true.
		ChildCannotTick,
		
		/// [ClassMetadata] Used for objects with hundreds of nested properties like animation data to stop the editor from hanging to build debug data.
		DebugTreeLeaf,

		/// [ClassMetadata] Used to make the first subclass of a class ignore all inherited showCategories and hideCategories commands

	// Blueprints that derive from native C++ classes that have bCanEverTick=true will always be able to tick
	// Blueprints that derive from exactly AActor or UActorComponent will always be able to tick
	// Otherwise, they can tick as long as the parent doesn't have meta=(ChildCannotTick) and either bCanBlueprintsTickByDefault is true or the parent has meta=(ChildCanTick)
	UPROPERTY(EditAnywhere, config, Category=Blueprints)
	uint32 bCanBlueprintsTickByDefault:1;

	/** Controls whether anim blueprint nodes that access member variables of their class directly should use the optimized path that avoids a thunk to the Blueprint VM. This will force all anim blueprints to be recompiled. */
	UPROPERTY(EditAnywhere, config, Category="Anim Blueprints")
	uint32 bOptimizeAnimBlueprintMemberVariableAccess:1;

	/** Controls whether by default we allow anim blueprint graph updates to be performed on non-game threads. This enables some extra checks in the anim blueprint compiler that will warn when unsafe operations are being attempted. This will force all anim blueprints to be recompiled. */

file
function     UEngine::UEngine

	EndStreamingPauseDelegate = NULL;

	bCanBlueprintsTickByDefault = true;
	bOptimizeAnimBlueprintMemberVariableAccess = true;
	bAllowMultiThreadedAnimationUpdate = true;

	bUseFixedFrameRate = false;
	FixedFrameRate = 30.f;