/ue-gameplay-cameras

Classic Camera Stack Reference (UE 5.8)

Everything here is in the Engine module (Source/Runtime/Engine/Classes/Camera, Classes/GameFramework), the CinematicCamera module, or the EngineCameras plugin. Build.cs: "Engine", plus "CinematicCamera" and "EngineCameras" as needed.

FMinimalViewInfo

Camera/CameraTypes.h. This is the struct every camera path produces.

APlayerCameraManager

Camera/PlayerCameraManager.h. UCLASS(notplaceable, transient, BlueprintType, Blueprintable, Config=Engine, MinimalAPI), base AActor.

Key state: PCOwner, CameraStyle (FName), DefaultFOV, DefaultOrthoWidth, DefaultAspectRatio, ViewTarget and PendingViewTarget (FTViewTarget), BlendTimeToGo, BlendParams (FViewTargetTransitionParams), ModifierList, DefaultModifiers, FreeCamDistance, ViewPitchMin, ViewPitchMax, ViewYawMin, ViewYawMax, ViewRollMin, ViewRollMax, FadeColor, FadeAmount, ColorScale, bIsOrthographic.

Virtuals worth overriding:

virtual void UpdateCamera(float DeltaTime);
virtual void DoUpdateCamera(float DeltaTime);
virtual void UpdateViewTarget(FTViewTarget& OutVT, float DeltaTime);
virtual void UpdateViewTargetInternal(FTViewTarget& OutVT, float DeltaTime);
virtual void ApplyCameraModifiers(float DeltaTime, FMinimalViewInfo& InOutPOV);
virtual void InitializeFor(class APlayerController* PC);
virtual void ProcessViewRotation(float DeltaTime, FRotator& OutViewRotation, FRotator& OutDeltaRot);
virtual void SetViewTarget(class AActor* NewViewTarget, FViewTargetTransitionParams TransitionParams = FViewTargetTransitionParams());
virtual void AssignViewTarget(AActor* NewTarget, FTViewTarget& VT, struct FViewTargetTransitionParams TransitionParams = FViewTargetTransitionParams());
virtual FRotator GetCameraRotation() const;
virtual FVector GetCameraLocation() const;
virtual void LimitViewPitch(FRotator& ViewRotation, float InViewPitchMin, float InViewPitchMax);
virtual void LimitViewYaw(FRotator& ViewRotation, float InViewYawMin, float InViewYawMax);
virtual void LimitViewRoll(FRotator& ViewRotation, float InViewRollMin, float InViewRollMax);
virtual void DisplayDebug(class UCanvas* Canvas, const FDebugDisplayInfo& DebugDisplay, float& YL, float& YPos) override;

Read-only accessors: AActor* GetViewTarget() const, virtual const FMinimalViewInfo& GetCameraCacheView() const, virtual const FMinimalViewInfo& GetLastFrameCameraCacheView() const, float GetCameraCacheTime() const, float GetLockedFOV() const. OnBlendComplete() returns the FOnBlendComplete event fired when PendingViewTarget is promoted.

BlueprintUpdateCamera(AActor* CameraTarget, FVector& NewCameraLocation, FRotator& NewCameraRotation, float& NewCameraFOV) is the Blueprint hook that short-circuits UpdateViewTarget when it returns true.

FTViewTarget and FViewTargetTransitionParams

USTRUCT(BlueprintType)
struct FTViewTarget
{
    TObjectPtr<class AActor> Target;
    struct FMinimalViewInfo POV;
    class APlayerState* GetPlayerState() const;
    void SetNewTarget(AActor* NewTarget);
    class APawn* GetTargetPawn() const;
    bool Equal(const FTViewTarget& OtherTarget) const;
    void CheckViewTarget(APlayerController* OwningController);
};

FViewTargetTransitionParams holds BlendTime, BlendFunction (TEnumAsByte<enum EViewTargetBlendFunction>), BlendExp, bLockOutgoing, and float GetBlendAlpha(const float& TimePct) const.

EViewTargetBlendOrder (VTBlendOrder_Base, VTBlendOrder_Override) exists alongside EViewTargetBlendFunction for systems that stack blends.

UCameraComponent

Camera/CameraComponent.h, base USceneComponent, ClassGroup=Camera, meta=(BlueprintSpawnableComponent).

Properties: FieldOfView, FirstPersonFieldOfView, FirstPersonScale, OrthoWidth, bAutoCalculateOrthoPlanes, AutoPlaneShift, OrthoNearClipPlane, OrthoFarClipPlane, AspectRatio, bConstrainAspectRatio, bUseFieldOfViewForLOD, Overscan, bScaleResolutionWithOverscan, bCropOverscan, ProjectionMode, bLockToHmd, bUsePawnControlRotation, bEnableFirstPersonFieldOfView, bEnableFirstPersonScale, PostProcessBlendWeight, PostProcessSettings.

Setters exist for nearly all of them (SetFieldOfView, SetOrthoWidth, SetAspectRatio, SetProjectionMode, SetPostProcessBlendWeight, …). The one virtual you normally override is:

virtual void GetCameraView(float DeltaTime, FMinimalViewInfo& DesiredView);

Also useful: void AddOrUpdateBlendable(TScriptInterface<IBlendableInterface> InBlendableObject, float InWeight = 1.0f), void RemoveBlendable(TScriptInterface<IBlendableInterface> InBlendableObject), void AddAdditiveOffset(FTransform const& Transform, float FOV) / ClearAdditiveOffset() / GetAdditiveOffset(FTransform& OutAdditiveOffset, float& OutAdditiveFOVOffset) const, void AddExtraPostProcessBlend(FPostProcessSettings const& PPSettings, float PPBlendWeight) / ClearExtraPostProcessBlends() (stored only — not applied by GetCameraView, and only the level-editor viewport reads them, Camera/CameraComponent.h:323), and virtual void NotifyCameraCut().

ACameraActor wraps one: TEnumAsByte<EAutoReceiveInput::Type> AutoActivateForPlayer, int32 GetAutoActivatePlayerIndex() const, class UCameraComponent* GetCameraComponent() const.

Post-process on a camera

UCameraComponent::PostProcessSettings is an FPostProcessSettings (Engine/Scene.h) blended at PostProcessBlendWeight (0 = off, 1 = full). Every field is gated by a matching bOverride_ flag — setting DepthOfFieldFstop without bOverride_DepthOfFieldFstop = true does nothing:

// MyCharacter.cpp - include Camera/CameraComponent.h
void AMyCharacter::ApplyCinematicLook(UCameraComponent* Camera)
{
    Camera->PostProcessBlendWeight = 1.f;
    Camera->PostProcessSettings.bOverride_MotionBlurAmount = true;
    Camera->PostProcessSettings.MotionBlurAmount = 0.2f;
    Camera->PostProcessSettings.bOverride_DepthOfFieldFstop = true;
    Camera->PostProcessSettings.DepthOfFieldFstop = 2.8f;
}

Camera post-process is blended after all volumes (LocalPlayer.cpp:970), so it overrides any APostProcessVolume regardless of volume priority. FWeightedBlendables inside the settings holds material blendables added by AddOrUpdateBlendable.

UCameraModifier

Camera/CameraModifier.h, UCLASS(BlueprintType, Blueprintable, MinimalAPI), base UObject.

virtual bool ModifyCamera(float DeltaTime, struct FMinimalViewInfo& InOutPOV);
virtual bool ProcessViewRotation(class AActor* ViewTarget, float DeltaTime, FRotator& OutViewRotation, FRotator& OutDeltaRot);
virtual void AddedToCamera(APlayerCameraManager* Camera);
virtual void UpdateAlpha(float DeltaTime);
virtual float GetTargetAlpha();
virtual void EnableModifier();
virtual void DisableModifier(bool bImmediate = false);
virtual void ToggleModifier();
virtual bool IsDisabled() const;
virtual bool IsPendingDisable() const;
virtual AActor* GetViewTarget() const;
virtual void DisplayDebug(class UCanvas* Canvas, const FDebugDisplayInfo& DebugDisplay, float& YL, float& YPos);

State: Priority (uint8, 0 = highest), bExclusive, bDebug, CameraOwner, AlphaInTime, AlphaOutTime, Alpha. Blueprint-only hooks: BlueprintModifyCamera and BlueprintModifyPostProcess.

There is a second, non-virtual-extension overload virtual void ModifyCamera(float DeltaTime, FVector ViewLocation, FRotator ViewRotation, float FOV, FVector& NewViewLocation, FRotator& NewViewRotation, float& NewFOV) used internally to bridge to Blueprint. Override the FMinimalViewInfo form.

Camera shakes

UCameraShakeBase (Camera/CameraShakeBase.h, UCLASS(Abstract, Blueprintable, EditInlineNew, MinimalAPI)) owns a private RootShakePattern and exposes UCameraShakePattern* GetRootShakePattern() const, void SetRootShakePattern(UCameraShakePattern* InPattern) and the template helper ChangeRootShakePattern<ShakePatternType>(). Runtime state: bSingleInstance, ShakeScale, APlayerCameraManager* GetCameraManager() const, ECameraShakePlaySpace GetPlaySpace() const, const FMatrix& GetUserPlaySpaceMatrix() const.

Lifecycle calls the manager makes: StartShake(APlayerCameraManager* Camera, float Scale, ECameraShakePlaySpace InPlaySpace, FRotator UserPlaySpaceRot = FRotator::ZeroRotator) or StartShake(const FCameraShakeBaseStartParams& Params), then UpdateAndApplyCameraShake(float DeltaTime, float Alpha, FMinimalViewInfo& InOutPOV), bool IsFinished() const, StopShake(bool bImmediately = true), TeardownShake().

Writing a shake pattern

// MyShakePattern.h
#pragma once

#include "CoreMinimal.h"
#include "Shakes/SimpleCameraShakePattern.h"
#include "MyShakePattern.generated.h"

UCLASS()
class MYGAME_API UMyShakePattern : public USimpleCameraShakePattern
{
    GENERATED_BODY()

public:
    UMyShakePattern(const FObjectInitializer& ObjInit);

    UPROPERTY(EditAnywhere, Category = "Shake")
    float PitchAmplitude = 2.f;

    UPROPERTY(EditAnywhere, Category = "Shake")
    float PitchFrequency = 10.f;

protected:
    virtual void UpdateShakePatternImpl(const FCameraShakePatternUpdateParams& Params, FCameraShakePatternUpdateResult& OutResult) override;
};

// MyShakePattern.cpp
#include "MyShakePattern.h"

UMyShakePattern::UMyShakePattern(const FObjectInitializer& ObjInit)
    : Super(ObjInit)
{
    Duration = 0.4f;
    BlendInTime = 0.05f;
    BlendOutTime = 0.2f;
}

void UMyShakePattern::UpdateShakePatternImpl(const FCameraShakePatternUpdateParams& Params, FCameraShakePatternUpdateResult& OutResult)
{
    // Advance the inherited State: it tracks Duration and the blend in/out, and IsFinishedImpl reads it.
    const float BlendWeight = State.Update(Params.DeltaTime);
    OutResult.Rotation.Pitch = PitchAmplitude * FMath::Sin(State.GetElapsedTime() * PitchFrequency * 2.f * UE_PI);
    OutResult.ApplyScale(BlendWeight);
}

USimpleCameraShakePattern (module "EngineCameras") supplies Duration, BlendInTime, BlendOutTime and implements the info/start/finish/stop/teardown hooks, so a subclass usually only writes UpdateShakePatternImpl. That override must call State.Update(Params.DeltaTime) and scale its output by the returned weight, as the shipped patterns do (PerlinNoiseCameraShakePattern.cpp:49-50); IsFinishedImpl returns !State.IsPlaying(), so a pattern that never updates State never finishes. The full protected set on UCameraShakePattern:

virtual void GetShakePatternInfoImpl(FCameraShakeInfo& OutInfo) const;
virtual void StartShakePatternImpl(const FCameraShakePatternStartParams& Params);
virtual void UpdateShakePatternImpl(const FCameraShakePatternUpdateParams& Params, FCameraShakePatternUpdateResult& OutResult);
virtual void ScrubShakePatternImpl(const FCameraShakePatternScrubParams& Params, FCameraShakePatternUpdateResult& OutResult);
virtual bool IsFinishedImpl() const;
virtual void StopShakePatternImpl(const FCameraShakePatternStopParams& Params);
virtual void TeardownShakePatternImpl();

Shipped patterns

ULegacyCameraShake (UCLASS(MinimalAPI, Blueprintable, HideCategories = (CameraShakePattern))) keeps the oscillator-style authoring surface (FFOscillator, FROscillator, FVOscillator, OscillationDuration, OscillationBlendInTime, OscillationBlendOutTime) and offers the statics static ULegacyCameraShake* StartLegacyCameraShake(APlayerCameraManager* PlayerCameraManager, TSubclassOf<ULegacyCameraShake> ShakeClass, float Scale = 1.f, ECameraShakePlaySpace PlaySpace = ECameraShakePlaySpace::CameraLocal, FRotator UserPlaySpaceRot = FRotator::ZeroRotator) and static ULegacyCameraShake* StartLegacyCameraShakeFromSource(APlayerCameraManager* PlayerCameraManager, TSubclassOf<ULegacyCameraShake> ShakeClass, UCameraShakeSourceComponent* SourceComponent, float Scale = 1.f, ECameraShakePlaySpace PlaySpace = ECameraShakePlaySpace::CameraLocal, FRotator UserPlaySpaceRot = FRotator::ZeroRotator). UDefaultCameraShakeBase is a UCameraShakeBase whose RootShakePattern subobject class is UPerlinNoiseCameraShakePattern.

UCameraModifier_CameraShake

The manager creates one by default; it owns the running shakes.

virtual UCameraShakeBase* AddCameraShake(TSubclassOf<UCameraShakeBase> NewShake, const FAddCameraShakeParams& Params);
virtual void GetActiveCameraShakes(TArray<FActiveCameraShakeInfo>& ActiveCameraShakes) const;
virtual void RemoveCameraShake(UCameraShakeBase* ShakeInst, bool bImmediately = true);
virtual void RemoveAllCameraShakesOfClass(TSubclassOf<UCameraShakeBase> ShakeClass, bool bImmediately = true);
virtual void RemoveAllCameraShakesFromSource(const UCameraShakeSourceComponent* SourceComponent, bool bImmediately = true);
virtual void RemoveAllCameraShakesOfClassFromSource(TSubclassOf<UCameraShakeBase> ShakeClass, const UCameraShakeSourceComponent* SourceComponent, bool bImmediately = true);
virtual void RemoveAllCameraShakes(bool bImmediately = true);

FAddCameraShakeParams carries Scale, PlaySpace, UserPlaySpaceRot, SourceComponent, Initializer (FOnInitializeCameraShake) and DurationOverride (TOptional<float>). Supplying an Initializer opts the shake out of pooling.

UCameraShakeSourceComponent

Attenuation (ECameraShakeAttenuation), InnerAttenuationRadius, OuterAttenuationRadius, CameraShake, bAutoStart. Methods: void Start(), void StartCameraShake(TSubclassOf<UCameraShakeBase> InCameraShake, float Scale=1.f, ECameraShakePlaySpace PlaySpace = ECameraShakePlaySpace::CameraLocal, FRotator UserPlaySpaceRot = FRotator::ZeroRotator), void StopAllCameraShakesOfType(TSubclassOf<UCameraShakeBase> InCameraShake, bool bImmediately = true), void StopAllCameraShakes(bool bImmediately = true), float GetAttenuationFactor(const FVector& Location) const. ACameraShakeSourceActor is the placeable actor form.

Camera animation sequences

UEngineCamerasSubsystem (a UWorldSubsystem in the EngineCameras plugin) plays UCameraAnimationSequence assets on a player:

static UEngineCamerasSubsystem* GetEngineCamerasSubsystem(const UWorld* InWorld);
FCameraAnimationHandle PlayCameraAnimation(APlayerController* PlayerController, UCameraAnimationSequence* Sequence, FCameraAnimationParams Params);
bool IsCameraAnimationActive(APlayerController* PlayerController, const FCameraAnimationHandle& Handle) const;
void StopCameraAnimation(APlayerController* PlayerController, const FCameraAnimationHandle& Handle, bool bImmediate = false);
void StopAllCameraAnimationsOf(APlayerController* PlayerController, UCameraAnimationSequence* Sequence, bool bImmediate = false);
void StopAllCameraAnimations(APlayerController* PlayerController, bool bImmediate = false);

UCameraAnimationCameraModifier is the modifier that applies them.

USpringArmComponent

GameFramework/SpringArmComponent.h, base USceneComponent.

Accessors and virtuals: FRotator GetTargetRotation() const, bool IsCollisionFixApplied() const, static const FName SocketName, virtual FRotator GetDesiredRotation() const, virtual void UpdateDesiredArmLocation(bool bDoTrace, bool bDoLocationLag, bool bDoRotationLag, float DeltaTime), virtual FVector BlendLocations(const FVector& DesiredArmLocation, const FVector& TraceHitLocation, bool bHitSomething, float DeltaTime).

Actor and pawn hooks

// AActor
virtual void CalcCamera(float DeltaTime, struct FMinimalViewInfo& OutResult);
virtual bool HasActiveCameraComponent(bool bForceFindCamera = false) const;
virtual bool HasActivePawnControlCameraComponent() const;
virtual void GetActorEyesViewPoint(FVector& OutLocation, FRotator& OutRotation) const;
uint8 bFindCameraComponentWhenViewTarget:1;

// APawn
virtual FRotator GetViewRotation() const;
virtual FVector GetPawnViewLocation() const;
virtual void RecalculateBaseEyeHeight();
float BaseEyeHeight;

// APlayerController
virtual void GetPlayerViewPoint(FVector& out_Location, FRotator& out_Rotation) const override;
virtual void CalcCamera(float DeltaTime, struct FMinimalViewInfo& OutResult) override;
virtual void SpawnPlayerCameraManager();
virtual void AutoManageActiveCameraTarget(AActor* SuggestedTarget);

APawn does not declare CalcCamera — the inherited AActor version runs, which is why bFindCameraComponentWhenViewTarget (default true on every actor, Actor.cpp:320) usually routes to the camera component instead. A subclass override of CalcCamera always runs for a non-ACameraActor view target; only calling Super brings the component lookup back.

Cinematic cameras

UCineCameraComponent (module "CinematicCamera", base UCameraComponent, hides SetFieldOfView/SetAspectRatio):

Helpers: float GetHorizontalFieldOfView() const, float GetVerticalFieldOfView() const, FString GetFilmbackPresetName() const, void SetFilmbackPresetByName(const FString& InPresetName), FString GetLensPresetName() const, void SetLensPresetByName(const FString& InPresetName).

ACineCameraActor adds FCameraLookatTrackingSettings LookatTrackingSettings, FVector GetLookatLocation() const, bool ShouldTickForTracking() const and overrides NotifyCameraCut().

Rigs:

Both override GetDefaultAttachComponent() so attaching a camera actor lands on the mount.