Files
UnrealEngine/Engine/Source/Runtime/MovieScene/Public/MovieSceneCommonHelpers.h
2025-05-18 13:04:45 +08:00

649 lines
26 KiB
C++

// Copyright Epic Games, Inc. All Rights Reserved.
#pragma once
#include "CoreMinimal.h"
#include "Engine/EngineTypes.h"
#include "UObject/UnrealType.h"
#include "UObject/ObjectKey.h"
#include "Curves/KeyHandle.h"
#include "Misc/FrameNumber.h"
#include "UObject/WeakFieldPtr.h"
class AActor;
class UCameraComponent;
class UMovieScene;
class UMovieSceneSection;
class UMovieSceneSubSection;
class UMovieSceneSequence;
class USceneComponent;
class USoundBase;
template <class TClass> class TSubclassOf;
class UMovieSceneCustomBinding;
struct FRichCurve;
enum class EMovieSceneKeyInterpolation : uint8;
struct FMovieSceneSequenceID;
class UMovieSceneCondition;
class UMovieSceneTrack;
namespace UE::MovieScene
{
struct FSharedPlaybackState;
}
class MovieSceneHelpers
{
public:
/*
* Helper struct to cache the package dirty state and then to restore it
* after this leaves scope. This is for a few minor areas where calling
* functions on actors dirties them, but Sequencer doesn't actually want
* the package to be dirty as it causes Sequencer to unnecessairly dirty
* actors.
*/
struct FMovieSceneScopedPackageDirtyGuard
{
MOVIESCENE_API FMovieSceneScopedPackageDirtyGuard(class USceneComponent* InComponent);
MOVIESCENE_API virtual ~FMovieSceneScopedPackageDirtyGuard();
private:
class USceneComponent* Component;
bool bPackageWasDirty;
};
/**
* @return Whether the section is keyable (active, on a track that is not muted, etc
*/
static MOVIESCENE_API bool IsSectionKeyable(const UMovieSceneSection*);
/**
* Finds a section that exists at a given time
*
* @param Time The time to find a section at
* @param RowIndex Limit the search to a given row index
* @return The found section or null
*/
static MOVIESCENE_API UMovieSceneSection* FindSectionAtTime( TArrayView<UMovieSceneSection* const> Sections, FFrameNumber Time, int32 RowIndex = INDEX_NONE );
/**
* Finds the nearest section to the given time
*
* @param Time The time to find a section at
* @param RowIndex Limit the search to a given row index
* @return The found section or null
*/
static MOVIESCENE_API UMovieSceneSection* FindNearestSectionAtTime( TArrayView<UMovieSceneSection* const> Sections, FFrameNumber Time, int32 RowIndex = INDEX_NONE );
/** Find the next section that doesn't overlap - the section that has the next closest start time to the requested start time */
static MOVIESCENE_API UMovieSceneSection* FindNextSection(TArrayView<UMovieSceneSection* const> Sections, FFrameNumber Time);
/** Find the previous section that doesn't overlap - the section that has the previous closest start time to the requested start time */
static MOVIESCENE_API UMovieSceneSection* FindPreviousSection(TArrayView<UMovieSceneSection* const> Sections, FFrameNumber Time);
/*
* Fix up consecutive sections so that there are no gaps
*
* @param Sections All the sections
* @param Section The section that was modified
* @param bDelete Was this a deletion?
* @param bCleanUp Should we cleanup any invalid sections?
* @return Whether the list of sections was modified as part of the clean-up
*/
static MOVIESCENE_API bool FixupConsecutiveSections(TArray<UMovieSceneSection*>& Sections, UMovieSceneSection& Section, bool bDelete, bool bCleanUp = false);
/**
* Fix up consecutive sections so that there are no gaps, but there can be overlaps, in which case the sections
* blend together.
*
* @param Sections All the sections
* @param Section The section that was modified
* @param bDelete Was this a deletion?
* @param bCleanUp Should we cleanup any invalid sections?
* @return Whether the list of sections was modified as part of the clean-up
*/
static MOVIESCENE_API bool FixupConsecutiveBlendingSections(TArray<UMovieSceneSection*>& Sections, UMovieSceneSection& Section, bool bDelete, bool bCleanUp = false);
/*
* Sort consecutive sections so that they are in order based on start time
*/
static MOVIESCENE_API void SortConsecutiveSections(TArray<UMovieSceneSection*>& Sections);
/*
* Gather up descendant movie scenes from the incoming sequence
*/
static MOVIESCENE_API void GetDescendantMovieScenes(UMovieSceneSequence* InSequence, TArray<UMovieScene*> & InMovieScenes);
/*
* Gather up descendant movie scene sub-sections from the incoming movie scene
*/
static MOVIESCENE_API void GetDescendantSubSections(const UMovieScene* InMovieScene, TArray<UMovieSceneSubSection*>& InSubSections);
/**
* Get the scene component from the runtime object
*
* @param Object The object to get the scene component for
* @return The found scene component
*/
static MOVIESCENE_API USceneComponent* SceneComponentFromRuntimeObject(UObject* Object);
static MOVIESCENE_API UObject* ResolveSceneComponentBoundObject(UObject* Object);
/**
* Get the active camera component from the actor
*
* @param InActor The actor to look for the camera component on
* @return The active camera component
*/
static MOVIESCENE_API UCameraComponent* CameraComponentFromActor(const AActor* InActor);
/**
* Find and return camera component from the runtime object
*
* @param Object The object to get the camera component for
* @return The found camera component
*/
static MOVIESCENE_API UCameraComponent* CameraComponentFromRuntimeObject(UObject* RuntimeObject);
/**
* Set the runtime object movable
*
* @param Object The object to set the mobility for
* @param Mobility The mobility of the runtime object
*/
static MOVIESCENE_API void SetRuntimeObjectMobility(UObject* Object, EComponentMobility::Type ComponentMobility = EComponentMobility::Movable);
/*
* Get the duration for the given sound
* @param Sound The sound to get the duration for
* @return The duration in seconds
*/
static MOVIESCENE_API float GetSoundDuration(USoundBase* Sound);
/**
* Sort predicate that sorts lower bounds of a range
*/
static bool SortLowerBounds(TRangeBound<FFrameNumber> A, TRangeBound<FFrameNumber> B)
{
return TRangeBound<FFrameNumber>::MinLower(A, B) == A && A != B;
}
/**
* Sort predicate that sorts upper bounds of a range
*/
static bool SortUpperBounds(TRangeBound<FFrameNumber> A, TRangeBound<FFrameNumber> B)
{
return TRangeBound<FFrameNumber>::MinUpper(A, B) == A && A != B;
}
/**
* Sort predicate that sorts overlapping sections by row primarily, then by overlap priority
*/
static MOVIESCENE_API bool SortOverlappingSections(const UMovieSceneSection* A, const UMovieSceneSection* B);
/*
* Get weight needed to modify the global difference in order to correctly key this section due to it possibly being blended by other sections.
* @param Section The Section who's weight we are calculating.
* @param Time we are at.
* @return Returns the weight that needs to be applied to the global difference to correctly key this section.
*/
static MOVIESCENE_API float CalculateWeightForBlending(UMovieSceneSection* SectionToKey, FFrameNumber Time);
/*
* Return a name unique to the binding names in the given movie scene
* @param InMovieScene The movie scene to look for existing possessables.
* @param InName The requested name to make unique.
* @return The unique name
*/
static MOVIESCENE_API FString MakeUniqueBindingName(UMovieScene* InMovieScene, const FString& InName);
/*
* Return a name unique to the spawnable names in the given movie scene
* @param InMovieScene The movie scene to look for existing spawnables.
* @param InName The requested name to make unique.
* @return The unique name
*/
static MOVIESCENE_API FString MakeUniqueSpawnableName(UMovieScene* InMovieScene, const FString& InName);
/**
* Return a copy of the source object, suitable for use as a spawnable template.
* @param InSourceObject The source object to convert into a spawnable template
* @param InMovieScene The movie scene the spawnable template will be associated with
* @param InName The name to use for the spawnable template
* @return The spawnable template
*/
static MOVIESCENE_API UObject* MakeSpawnableTemplateFromInstance(UObject& InSourceObject, UMovieScene* InMovieScene, FName InName);
/*
* Returns whether the given ObjectId is valid and is currently bound to at least 1 spawnable give the current context.
* More specifically, if a FMovieSceneSpawnable exists with this ObjectId, true will be returned.
* If a Level Sequence binding reference exists with a Custom Binding implementing MovieSceneSpawnableBindingBase, true will be returned.
* If a Level Sequence binding reference exists with a Custom Binding implementing MovieSceneReplaceableBindingBase and the Context is an editor world, then true will be returned.
* Otherwise, false will be returned.
*/
static MOVIESCENE_API bool IsBoundToAnySpawnable(UMovieSceneSequence* Sequence, const FGuid& ObjectId, TSharedRef<const UE::MovieScene::FSharedPlaybackState> SharedPlaybackState);
/*
* Returns whether the given ObjectId is valid and is the given bindingindex is currently bound to a spawnable give the current context.
* More specifically, if a FMovieSceneSpawnable exists with this ObjectId, true will be returned.
* If a Level Sequence binding reference for this guid with the given BindingIndex exists with a Custom Binding implementing MovieSceneSpawnableBindingBase, true will be returned.
* If a Level Sequence binding reference for this guid with the given BindingIndex exists with a Custom Binding implementing MovieSceneReplaceableBindingBase and the Context is an editor world, then true will be returned.
* Otherwise, false will be returned.
*/
static MOVIESCENE_API bool IsBoundToSpawnable(UMovieSceneSequence* Sequence, const FGuid& ObjectId, TSharedRef<const UE::MovieScene::FSharedPlaybackState> SharedPlaybackState, int32 BindingIndex = 0);
/*
* Attempts to create a new custom spawnable binding for the passed in UObject*.
* Where possible, it is preferred to call FSequencerUtilities::CreateOrReplaceBinding as it handles more cases. This should only be called in cases where there is no editor or sequencer context.
* FactoryCreatedActor may be passed in as an alternative option for creating the binding in the case an actor factory was able to create an actor from this object.
*/
static MOVIESCENE_API FGuid TryCreateCustomSpawnableBinding(UMovieSceneSequence* Sequence, UObject* CustomBindingObject);
/*
* Returns the single bound object currently bound to the given objectid and binding index (optional).
*/
static MOVIESCENE_API UObject* GetSingleBoundObject(UMovieSceneSequence* Sequence, const FGuid& ObjectId, TSharedRef<const UE::MovieScene::FSharedPlaybackState> SharedPlaybackState, int32 BindingIndex = 0);
/*
* If the binding for the given ObjectId supports object templates, returns the template, otherwise returns nullptr
*/
static MOVIESCENE_API UObject* GetObjectTemplate(UMovieSceneSequence* Sequence, const FGuid& ObjectId, TSharedRef<const UE::MovieScene::FSharedPlaybackState> SharedPlaybackState, int32 BindingIndex = 0);
/*
* If the binding for the given ObjectId supports object templates, sets the template and returns true, otherwise returns false
*/
static MOVIESCENE_API bool SetObjectTemplate(UMovieSceneSequence* Sequence, const FGuid& ObjectId, UObject* InSourceObject, TSharedRef<const UE::MovieScene::FSharedPlaybackState> SharedPlaybackState, int32 BindingIndex = 0);
/*
* Returns whether the binding for the given ObjectId supports object templates
*/
static MOVIESCENE_API bool SupportsObjectTemplate(UMovieSceneSequence* Sequence, const FGuid& ObjectId, TSharedRef<const UE::MovieScene::FSharedPlaybackState> SharedPlaybackState, int32 BindingIndex = 0);
/*
* If the binding for the given ObjectId supports object templates, copies the object template into the binding and returns true, otherwise returns false
*/
static MOVIESCENE_API bool CopyObjectTemplate(UMovieSceneSequence* Sequence, const FGuid& ObjectId, UObject* InSourceObject, TSharedRef<const UE::MovieScene::FSharedPlaybackState> SharedPlaybackState, int32 BindingIndex = 0);
#if WITH_EDITORONLY_DATA
/*
* Returns the bound object class for the binding for the given ObjectId.
*/
static MOVIESCENE_API const UClass* GetBoundObjectClass(UMovieSceneSequence* Sequence, const FGuid& ObjectId, int32 BindingIndex = 0);
#endif
/* Returns a sorted list of all custom binding type classes currently known. Slow, may desire to cache result*/
static void MOVIESCENE_API GetPrioritySortedCustomBindingTypes(TArray<const TSubclassOf<UMovieSceneCustomBinding>>& OutCustomBindingTypes);
/* For cases where the user does not have a IMovieScenePlayer with a shared playback state, creates a transient one. Use sparingly. */
static TSharedRef<UE::MovieScene::FSharedPlaybackState> MOVIESCENE_API CreateTransientSharedPlaybackState(UObject* WorldContext, UMovieSceneSequence* Sequence);
/* Finds the resolution context to use to resolve the given guid. */
static MOVIESCENE_API UObject* GetResolutionContext(UMovieSceneSequence* Sequence, const FGuid& ObjectId, const FMovieSceneSequenceID& SequenceID, TSharedRef<const UE::MovieScene::FSharedPlaybackState> SharedPlaybackState);
/* Given a movie scene track and an optional section inside it, returns an optional single condition that needs to be evaluated.
* If multiple conditions exist in the given scope (for example a track condition, a track row condition for the row the section is on, and a section),
* a UMovieSceneGroupCondition will be generated, and the caller is responsible for holding a reference to this new UObject.
* If bFromCompilation is true, then any generated conditions will be stored on the movie scene.
*/
static MOVIESCENE_API const UMovieSceneCondition* GetSequenceCondition(const UMovieSceneTrack* Track, const UMovieSceneSection* Section, bool bFromCompilation=false);
/* Helper function for evaluating a condition in a movie scene, taking advantage of any cacheing that may apply. */
static MOVIESCENE_API bool EvaluateSequenceCondition(const FGuid& BindingID, const FMovieSceneSequenceID& SequenceID, const UMovieSceneCondition* Condition, UObject* ConditionOwnerObject, TSharedRef<const UE::MovieScene::FSharedPlaybackState> SharedPlaybackState);
};
/**
* Manages bindings to keyed properties for a track instance.
* Calls UFunctions to set the value on runtime objects
*/
class FTrackInstancePropertyBindings
{
public:
MOVIESCENE_API FTrackInstancePropertyBindings(FName InPropertyName, const FString& InPropertyPath);
/**
* Calls the setter function for a specific runtime object or if the setter function does not exist, the property is set directly
*
* @param InRuntimeObject The runtime object whose function to call
* @param PropertyValue The new value to assign to the property
*/
template <typename ValueType>
void CallFunction(UObject& InRuntimeObject, typename TCallTraits<ValueType>::ParamType PropertyValue)
{
FResolvedPropertyAndFunction PropAndFunction = FindOrAdd(InRuntimeObject);
FProperty* Property = PropAndFunction.ResolvedProperty.GetValidProperty();
if (Property && Property->HasSetter())
{
Property->CallSetter(&InRuntimeObject, &PropertyValue);
}
else if (UFunction* SetterFunction = PropAndFunction.SetterFunction.Get())
{
InvokeSetterFunction(&InRuntimeObject, SetterFunction, PropertyValue);
}
else if (ValueType* Val = PropAndFunction.GetPropertyAddress<ValueType>())
{
*Val = MoveTempIfPossible(PropertyValue);
}
if (UFunction* NotifyFunction = PropAndFunction.NotifyFunction.Get())
{
InRuntimeObject.ProcessEvent(NotifyFunction, nullptr);
}
}
/**
* Calls the setter function for a specific runtime object or if the setter function does not exist, the property is set directly
*
* @param InRuntimeObject The runtime object whose function to call
* @param PropertyValue The new value to assign to the property
*/
MOVIESCENE_API void CallFunctionForEnum( UObject& InRuntimeObject, int64 PropertyValue );
/**
* Rebuilds the property and function mappings for a single runtime object, and adds them to the cache
*
* @param InRuntimeObject The object to cache mappings for
*/
MOVIESCENE_API void CacheBinding(const UObject& InRuntimeObject);
/**
* Gets the FProperty that is bound to the track instance.
*
* @param Object The Object that owns the property
* @return The property on the object if it exists
*/
MOVIESCENE_API FProperty* GetProperty(const UObject& Object);
/**
* Returns whether this binding is valid for the given object.
*
* @param Object The Object that owns the property
* @return Whether the property binding is valid
*/
MOVIESCENE_API bool HasValidBinding(const UObject& Object);
/**
* Gets the structure type of the bound property if it is a property of that type.
*
* @param Object The Object that owns the property
* @return The structure type
*/
MOVIESCENE_API const UStruct* GetPropertyStruct(const UObject& Object);
/**
* Gets the current value of a property on an object
*
* @param Object The object to get the property from
* @return ValueType The current value
*/
template <typename ValueType>
ValueType GetCurrentValue(const UObject& Object)
{
ValueType Value{};
FResolvedPropertyAndFunction PropAndFunction = FindOrAdd(Object);
TryGetPropertyValue<ValueType>(PropAndFunction.ResolvedProperty, Value);
return Value;
}
/**
* Optionally gets the current value of a property on an object
*
* @param Object The object to get the property from
* @return (Optional) The current value of the property on the object
*/
template <typename ValueType>
TOptional<ValueType> GetOptionalValue(const UObject& Object)
{
ValueType Value{};
FResolvedPropertyAndFunction PropAndFunction = FindOrAdd(Object);
if (TryGetPropertyValue<ValueType>(PropAndFunction.ResolvedProperty, Value))
{
return Value;
}
return TOptional<ValueType>();
}
/**
* Static function for accessing a property value on an object without caching its address
*
* @param Object The object to get the property from
* @param InPropertyPath The path to the property to retrieve
* @return (Optional) The current value of the property on the object
*/
template <typename ValueType>
static TOptional<ValueType> StaticValue(const UObject* Object, const FString& InPropertyPath)
{
checkf(Object, TEXT("No object specified"));
FTrackInstancePropertyBindings Temp(NAME_None, InPropertyPath);
FResolvedProperty ResolvedProperty = ResolveProperty(Temp, *Object);
ValueType Value;
if (TryGetPropertyValue<ValueType>(ResolvedProperty, Value))
{
return Value;
}
return TOptional<ValueType>();
}
/**
* Gets the current value of a property on an object
*
* @param Object The object to get the property from
* @return ValueType The current value
*/
MOVIESCENE_API int64 GetCurrentValueForEnum(const UObject& Object);
/**
* Sets the current value of a property on an object
*
* @param Object The object to set the property on
* @param InValue The value to set
*/
template <typename ValueType>
void SetCurrentValue(UObject& Object, typename TCallTraits<ValueType>::ParamType InValue)
{
FResolvedPropertyAndFunction PropAndFunction = FindOrAdd(Object);
if (ValueType* Val = PropAndFunction.GetPropertyAddress<ValueType>())
{
*Val = InValue;
if (UFunction* NotifyFunction = PropAndFunction.NotifyFunction.Get())
{
Object.ProcessEvent(NotifyFunction, nullptr);
}
}
}
/** @return the property path that this binding was initialized from */
const FString& GetPropertyPath() const
{
return PropertyPath;
}
/** @return the property name that this binding was initialized from */
const FName& GetPropertyName() const
{
return PropertyName;
}
static MOVIESCENE_API FProperty* FindProperty(const UObject* Object, const FString& InPropertyPath);
private:
/**
* Wrapper for UObject::ProcessEvent that attempts to pass the new property value directly to the function as a parameter,
* but handles cases where multiple parameters or a return value exists. The setter parameter must be the first in the list,
* any other parameters will be default constructed.
*/
template<typename T>
static void InvokeSetterFunction(UObject* InRuntimeObject, UFunction* Setter, T&& InPropertyValue);
struct FResolvedProperty
{
TWeakFieldPtr<FProperty> Property;
void* ContainerAddress;
int32 ArrayIndex = INDEX_NONE;
FProperty* GetValidProperty() const
{
FProperty* PropertyPtr = Property.Get();
if (PropertyPtr && ContainerAddress && !PropertyPtr->HasAnyFlags(RF_BeginDestroyed | RF_FinishDestroyed))
{
return PropertyPtr;
}
return nullptr;
}
template<typename ValueType>
ValueType* GetPropertyAddress() const
{
if (FProperty* PropertyPtr = GetValidProperty())
{
if (ArrayIndex == INDEX_NONE)
{
return PropertyPtr->ContainerPtrToValuePtr<ValueType>(ContainerAddress);
}
else if (FArrayProperty* ArrayProp = CastFieldChecked<FArrayProperty>(PropertyPtr))
{
FScriptArrayHelper ArrayHelper(ArrayProp, ArrayProp->ContainerPtrToValuePtr<void>(ContainerAddress));
check(ArrayHelper.IsValidIndex(ArrayIndex));
return (ValueType*)ArrayHelper.GetRawPtr(ArrayIndex);
}
}
return nullptr;
}
FResolvedProperty()
: Property(nullptr)
, ContainerAddress(nullptr)
{}
};
struct FResolvedPropertyAndFunction
{
FResolvedProperty ResolvedProperty;
TWeakObjectPtr<UFunction> SetterFunction;
TWeakObjectPtr<UFunction> NotifyFunction;
template<typename ValueType>
ValueType* GetPropertyAddress() const
{
return ResolvedProperty.GetPropertyAddress<ValueType>();
}
FResolvedPropertyAndFunction()
: ResolvedProperty()
, SetterFunction( nullptr )
, NotifyFunction( nullptr )
{}
};
template <typename ValueType>
static bool TryGetPropertyValue(const FResolvedProperty& ResolvedProperty, ValueType& OutValue)
{
if (const ValueType* Value = ResolvedProperty.GetPropertyAddress<ValueType>())
{
OutValue = *Value;
return true;
}
return false;
}
static MOVIESCENE_API FResolvedProperty ResolvePropertyRecursive(FTrackInstancePropertyBindings& Bindings, void* BasePointer, UStruct* InStruct, TArray<FString>& InPropertyNames, uint32 Index);
static MOVIESCENE_API FResolvedProperty ResolveProperty(FTrackInstancePropertyBindings& Bindings, const UObject& Object);
static MOVIESCENE_API void FindProperty(FTrackInstancePropertyBindings& Bindings, void* BasePointer, UStruct* InStruct, const FString& InPropertyName, FResolvedProperty& OutResolvedProperty);
static MOVIESCENE_API FResolvedProperty FindPropertyAndArrayIndex(FTrackInstancePropertyBindings& Bindings, void* BasePointer, UStruct* InStruct, const FString& PropertyName);
/** Find or add the FResolvedPropertyAndFunction for the specified object */
MOVIESCENE_API FResolvedPropertyAndFunction FindOrAdd(const UObject& InObject);
private:
/** Mapping of objects to bound functions that will be called to update data on the track */
TMap< FObjectKey, FResolvedPropertyAndFunction > RuntimeObjectToFunctionMap;
/** Path to the property we are bound to */
FString PropertyPath;
/** Name of the function to call to set values */
FName FunctionName;
/** Name of a function to call when a value has been set */
FName NotifyFunctionName;
/** Actual name of the property we are bound to */
FName PropertyName;
};
/** Explicit specializations for bools */
template<> MOVIESCENE_API void FTrackInstancePropertyBindings::CallFunction<bool>(UObject& InRuntimeObject, TCallTraits<bool>::ParamType PropertyValue);
template<> MOVIESCENE_API bool FTrackInstancePropertyBindings::TryGetPropertyValue<bool>(const FResolvedProperty& ResolvedProperty, bool& OutValue);
template<> MOVIESCENE_API void FTrackInstancePropertyBindings::SetCurrentValue<bool>(UObject& Object, TCallTraits<bool>::ParamType InValue);
/** Explicit specializations for object pointers */
template<> MOVIESCENE_API void FTrackInstancePropertyBindings::CallFunction<UObject*>(UObject& InRuntimeObject, UObject* PropertyValue);
template<> MOVIESCENE_API bool FTrackInstancePropertyBindings::TryGetPropertyValue<UObject*>(const FResolvedProperty& ResolvedProperty, UObject*& OutValue);
template<> MOVIESCENE_API void FTrackInstancePropertyBindings::SetCurrentValue<UObject*>(UObject& Object, UObject* InValue);
template<typename T>
void FTrackInstancePropertyBindings::InvokeSetterFunction(UObject* InRuntimeObject, UFunction* Setter, T&& InPropertyValue)
{
// CacheBinding already guarantees that the function has >= 1 parameters
const int32 ParmsSize = Setter->ParmsSize;
// This should all be const really, but ProcessEvent only takes a non-const void*
void* InputParameter = const_cast<typename TDecay<T>::Type*>(&InPropertyValue);
// By default we try and use the existing stack value
uint8* Params = reinterpret_cast<uint8*>(InputParameter);
check(InRuntimeObject && Setter);
if (Setter->ReturnValueOffset != MAX_uint16 || Setter->NumParms > 0)
{
// Function has a return value or multiple parameters, we need to initialize memory for the entire parameter pack
// We use alloca here (as in UObject::ProcessEvent) to avoid a heap allocation. Alloca memory survives the current function's stack frame.
Params = reinterpret_cast<uint8*>(FMemory_Alloca(ParmsSize));
bool bFirstProperty = true;
for (FProperty* Property = Setter->PropertyLink; Property; Property = Property->PropertyLinkNext)
{
// Initialize the parameter pack with any param properties that reside in the container
if (Property->IsInContainer(ParmsSize))
{
Property->InitializeValue_InContainer(Params);
// The first encountered property is assumed to be the input value so initialize this with the user-specified value from InPropertyValue
if (Property->HasAnyPropertyFlags(CPF_Parm) && !Property->HasAnyPropertyFlags(CPF_ReturnParm) && bFirstProperty)
{
const bool bIsValid = ensureMsgf(sizeof(T) == Property->GetElementSize(), TEXT("Property type does not match for Sequencer setter function %s::%s (%" SIZE_T_FMT "bytes != %ibytes"), *InRuntimeObject->GetName(), *Setter->GetName(), sizeof(T), Property->GetElementSize());
if (bIsValid)
{
Property->CopyCompleteValue(Property->ContainerPtrToValuePtr<void>(Params), &InPropertyValue);
}
else
{
return;
}
}
bFirstProperty = false;
}
}
}
// Now we have the parameters set up correctly, call the function
InRuntimeObject->ProcessEvent(Setter, Params);
}