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> Unreal Engine API Reference > Runtime > UMG > Components > URetainerBox

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URetainerBox

The Retainer Box renders children widgets to a render target first before later rendering that render target to the screen.

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Inheritance Hierarchy

UObjectBase

UObjectBaseUtility

UObject

UVisual

UWidget

UPanelWidget

UContentWidget

URetainerBox

References

Module	UMG
Header	/Engine/Source/Runtime/UMG/Public/Components/RetainerBox.h
Include	#include "Components/RetainerBox.h"

Syntax

class URetainerBox : public UContentWidget

Remarks

The Retainer Box renders children widgets to a render target first before later rendering that render target to the screen. This allows both frequency and phase to be controlled so that the UI can actually render less often than the frequency of the main game render. It also has the side benefit of allow materials to be applied to the render target after drawing the widgets to apply a simple post process.

Single Child Caching / Performance

Variables

	Name	Description
bool	bRetainRender
TObjectPtr< UMa...	EffectMaterial	The effect to optionally apply to the render target.
TSharedPtr< cla...	MyRetainerWidget
int32	Phase	The Phase this widget will draw on.
int32	PhaseCount	The PhaseCount controls how many phases are possible know what to modulus the current frame count by to determine if this is the current frame to draw the widget on.
bool	RenderOnInvalidation	Should this widget redraw the contents it has every time it receives an invalidation request from it's children, similar to the invalidation panel.
bool	RenderOnPhase	Should this widget redraw the contents it has every time the phase occurs.
FName	TextureParameter	The texture sampler parameter of the , that we'll set to the render target.

Constructors

	Name	Description
	URetainerBox ( const FObjectInitializer& ObjectIn... )

Functions

	Name	Description
FGeometry	GetCachedAllottedGeometry()
UMaterialIns...	GetEffectMaterial()	Get the current dynamic effect material applied to the retainer box.
void	RequestRender()	Requests the retainer redrawn the contents it has.
void	SetEffectMaterial ( UMaterialInterface* EffectMate... )	Set a new effect material to the retainer widget.
void	SetRenderingPhase ( int32 RenderPhase, int32 TotalPhases )	Requests the retainer redrawn the contents it has.
void	SetRetainRendering ( bool bInRetainRendering )	Set the flag for if we retain the render or pass-through
void	SetTextureParameter ( FName TextureParameter )	Sets the name of the texture parameter to set the render target to on the material.

Overridden from UPanelWidget

		Name	Description
	void	OnSlotAdded ( UPanelSlot* Slot )
	void	OnSlotRemoved ( UPanelSlot* Slot )

Overridden from UWidget

	Name	Description
const FText	GetPaletteCategory()	Gets the palette category of the widget
TSharedRef< ...	RebuildWidget()	Function implemented by all subclasses of UWidget is called when the underlying SWidget needs to be constructed.
void	SynchronizeProperties()	Applies all properties to the native widget if possible.

Overridden from UVisual

		Name	Description
	void	ReleaseSlateResources ( bool bReleaseChildren )

Overridden from UObject

		Name	Description
	bool	CanEditChange ( const FProperty* InProperty )	Called by the editor to query whether a property of this object is allowed to be modified.