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  3. FRDGBuilder

FRDGBuilder

Use the render graph builder to build up a graph of passes and then call [Execute()](API\Runtime\RenderCore\FRDGBuilder\Execute) to process them.

API > API/Runtime > API/Runtime/RenderCore

References

   
Module RenderCore
Header /Engine/Source/Runtime/RenderCore/Public/RenderGraphBuilder.h
Include #include "RenderGraphBuilder.h"

Syntax

class FRDGBuilder

Remarks

Use the render graph builder to build up a graph of passes and then call Execute() to process them. Resource barriers and lifetimes are derived from RDG parameters in the pass parameter struct provided to each AddPass call. The resulting graph is compiled, culled, and executed in Execute(). The builder should be created on the stack and executed prior to destruction.

Variables

  Type Name Description
Public variable bool bEnabled  
Public variable FRDGBlackboard Blackboard The blackboard used to hold common data tied to the graph lifetime.
Public variable TArray< FRHICommandListImmediate::FQueuedCommandList, FConcurrentLinearArrayAllocator > CommandLists Array of all command lists to submit for AddCommandListSetupTask.
Public variable TOptional< UE::Tasks::FTaskEvent > DispatchTaskEvent  
Public variable TArray< FParallelPassSet, FRDGArrayAllocator > ParallelPassSets  
Public variable FRHICommandListImmediate & RHICmdList The RHI command list used for the render graph.
Public variable FRDGAllocator Root Allocator for all root graph allocations on the graph builder thread.
Public variable FRDGAllocator Task Allocator for async pass and parallel execute setup.
Public variable TArray< UE::Tasks::FTask, FRDGArrayAllocator > Tasks Array of all tasks for variants of AddSetupTask.
Public variable FRDGAllocator Transition Allocator for all allocations related to states / transitions.

Constructors

  Type Name Description
Public function    
Public function    

Destructors

  Type Name Description
Public function    

Functions

  Type Name Description
Public function UE::Tasks::FTask

AddCommandListSetupTask ( TaskLambda&& Task,
UE::Tasks::ETaskPriority Priority,
bool bCondition
)

  
Public function UE::Tasks::FTask

AddCommandListSetupTask ( TaskLambdaType&& TaskLambda,
UE::Tasks::ETaskPriority TaskPriority,
bool bCondition
)

  
Public function UE::Tasks::FTask

AddCommandListSetupTask ( TaskLambda&& Task,
UE::Tasks::FPipe* Pipe,
UE::Tasks::ETaskPriority Priority,
bool bCondition
)

  
Public function UE::Tasks::FTask

AddCommandListSetupTask ( TaskLambda&& Task,
PrerequisitesCollectionType&& Prerequisites,
UE::Tasks::ETaskPriority Priority,
bool bCondition
)

  
Public function UE::Tasks::FTask

AddCommandListSetupTask ( TaskLambdaType&& TaskLambda,
UE::Tasks::FPipe* Pipe,
UE::Tasks::ETaskPriority Priority,
bool bCondition
)

  
Public function UE::Tasks::FTask

AddCommandListSetupTask ( TaskLambdaType&& TaskLambda,
PrerequisitesCollectionType&& Prerequisites,
UE::Tasks::ETaskPriority Priority,
bool bCondition
)

  
Public function UE::Tasks::FTask

AddCommandListSetupTask ( TaskLambda&& Task,
UE::Tasks::FPipe* Pipe,
PrerequisitesCollectionType&& Prerequisites,
UE::Tasks::ETaskPriority Priority,
bool bCondition
)

  
Public function UE::Tasks::FTask

AddCommandListSetupTask ( TaskLambdaType&& TaskLambda,
UE::Tasks::FPipe* Pipe,
PrerequisitesCollectionType&& Prerequisites,
UE::Tasks::ETaskPriority Priority,
bool bCondition
)

  
Public function UE::Tasks::FTask

AddCommandListSetupTask ( TaskLambdaType&& TaskLambda,
bool bCondition
)

  
Public function UE::Tasks::FTask

AddCommandListSetupTask ( TaskLambda&& Task,
bool bCondition
)

 Launches a task that is synced prior to graph execution.
Public function void A hint to the builder to flush work to the RHI thread after the last queued pass on the execution timeline.
Public function FRDGPassRef

AddPass ( FRDGEventName&& Name,
const ParameterStructType* ParameterStruct,
ERDGPassFlags Flags,
ExecuteLambdaType&& ExecuteLambda
)

 Adds a lambda pass to the graph with an accompanied pass parameter struct.
Public function FRDGPassRef

AddPass ( FRDGEventName&& Name,
ERDGPassFlags Flags,
ExecuteLambdaType&& ExecuteLambda
)

 Adds a lambda pass to the graph without any parameters.
Public function FRDGPassRef

AddPass ( FRDGEventName&& Name,
const FShaderParametersMetadata* ParametersMetadata,
const void* ParameterStruct,
ERDGPassFlags Flags,
ExecuteLambdaType&& ExecuteLambda
)

 Adds a lambda pass to the graph with a runtime-generated parameter struct.
Public function void

AddPassDependency ( FRDGPass* Producer,
FRDGPass* Consumer
)

 Adds a user-defined dependency between two passes.
Public function UE::Tasks::FTask

AddSetupTask ( TaskLambdaType&& TaskLambda,
bool bCondition
)

  
Public function UE::Tasks::FTask

AddSetupTask ( TaskLambdaType&& TaskLambda,
UE::Tasks::ETaskPriority Priority,
bool bCondition
)

  
Public function UE::Tasks::FTask

AddSetupTask ( TaskLambda&& Task,
UE::Tasks::FPipe* Pipe,
UE::Tasks::ETaskPriority Priority,
bool bCondition
)

  
Public function UE::Tasks::FTask

AddSetupTask ( TaskLambda&& Task,
PrerequisitesCollectionType&& Prerequisites,
UE::Tasks::ETaskPriority Priority,
bool bCondition
)

  
Public function UE::Tasks::FTask

AddSetupTask ( TaskLambdaType&& TaskLambda,
UE::Tasks::FPipe* Pipe,
UE::Tasks::ETaskPriority Priority,
bool bCondition
)

  
Public function UE::Tasks::FTask

AddSetupTask ( TaskLambdaType&& TaskLambda,
PrerequisitesCollectionType&& Prerequisites,
UE::Tasks::ETaskPriority Priority,
bool bCondition
)

  
Public function UE::Tasks::FTask

AddSetupTask ( TaskLambda&& Task,
UE::Tasks::FPipe* Pipe,
PrerequisitesCollectionType&& Prerequisites,
UE::Tasks::ETaskPriority Priority,
bool bCondition
)

  
Public function UE::Tasks::FTask

AddSetupTask ( TaskLambdaType&& TaskLambda,
UE::Tasks::FPipe* Pipe,
PrerequisitesCollectionType&& Prerequisites,
UE::Tasks::ETaskPriority Priority,
bool bCondition
)

  
Public function UE::Tasks::FTask

AddSetupTask ( TaskLambda&& Task,
UE::Tasks::ETaskPriority Priority,
bool bCondition
)

  
Public function UE::Tasks::FTask

AddSetupTask ( TaskLambda&& Task,
bool bCondition
)

 Launches a task that is synced prior to graph execution.
Public function void

AddTextureTransition ( FRDGTexture* Texture,
FRDGTextureSubresourceState& StateBefore,
FRDGTextureSubresourceState& StateAfter,
FilterSubresourceLambdaType&& FilterSubresourceLambda
)

  
Public function void *

Alloc ( uint64 SizeInBytes,
uint32 AlignInBytes
)

 Allocates raw memory using an allocator tied to the lifetime of the graph.
Public function TArray< ObjectType, SceneRenderingAllocator > & Allocates a C++ array where both the array and the data are tied to the lifetime of the graph.
Public function ObjectType *

AllocObject ( TArgs&&... Args
)

 Allocates a C++ object using an allocator tied to the lifetime of the graph.
Public function TStridedView< BaseParameterStructType >

AllocParameters ( const FShaderParametersMetadata* ParametersMetadata,
uint32 NumStructs
)

 Allocates an array of data-driven parameter structs with a lifetime tied to graph execution.
Public function ParameterStructType *

AllocParameters ( ParameterStructType* StructToCopy
)

 Allocates a parameter struct with a lifetime tied to graph execution, and copies contents from an existing parameters struct.
Public function ParameterStructType * Allocates a parameter struct with a lifetime tied to graph execution.
Public function BaseParameterStructType *

AllocParameters ( const FShaderParametersMetadata* ParametersMetadata
)

 Allocates a data-driven parameter struct with a lifetime tied to graph execution.
Public function PODType * Allocates POD memory using an allocator tied to the lifetime of the graph.
Public function PODType *

AllocPODArray ( uint32 Count
)

 Allocates POD memory using an allocator tied to the lifetime of the graph.
Public function void Manually begins a new GPU event scope.
Public function Static FString

BeginResourceDump ( const TCHAR* Cmd
)

  
Public function const TRefCountPtr< FRDGPooledBuffer > &  
Public function const TRefCountPtr< IPooledRenderTarget > & For graph-created resources, this forces immediate allocation of the underlying pooled resource, effectively promoting it to an external resource.
Public function FRHIUniformBuffer * For a graph-created uniform buffer, this forces immediate allocation of the underlying resource, effectively promoting it to an external resource.
Public function FRDGBufferRef

CreateBuffer ( const FRDGBufferDesc& Desc,
const TCHAR* Name,
ERDGBufferFlags Flags
)

 Create graph tracked buffer from a descriptor.
Public function FRDGBufferRef

CreateBuffer ( const FRDGBufferDesc& Desc,
const TCHAR* Name,
FRDGBufferNumElementsCallback&& NumElementsCallback,
ERDGBufferFlags Flags
)

 A variant of CreateBuffer where users supply NumElements through a callback.
Public function FRDGBufferSRVRef

CreateSRV ( FRDGBufferRef Buffer,
EPixelFormat Format
)

  
Public function FRDGBufferSRVRef

CreateSRV ( const FRDGBufferSRVDesc& Desc
)

 Create graph tracked SRV for a buffer from a descriptor.
Public function FRDGTextureSRVRef

CreateSRV ( const FRDGTextureSRVDesc& Desc
)

 Create graph tracked SRV for a texture from a descriptor.
Public function FRDGTextureRef

CreateTexture ( const FRDGTextureDesc& Desc,
const TCHAR* Name,
ERDGTextureFlags Flags
)

 Create graph tracked texture from a descriptor.
Public function FRDGTextureUAVRef  
Public function FRDGBufferUAVRef Create graph tracked UAV for a buffer from a descriptor.
Public function FRDGTextureUAVRef Create graph tracked UAV for a texture from a descriptor.
Public function FRDGBufferUAVRef  
Public function TRDGUniformBufferRef< ParameterStructType >

CreateUniformBuffer ( const ParameterStructType* ParameterStruct
)

 Creates a graph tracked uniform buffer which can be attached to passes.
Public function Static void

DumpDraw ( const FRDGEventName& DrawEventName
)

  
Public function void Manually ends the current GPU event scope.
Public function void

Execute ()

 Executes the queued passes, managing setting of render targets (RHI RenderPasses), resource transitions and queued texture extraction.
Public function Const FRDGBuffer *

FindExternalBuffer ( FRDGPooledBuffer* ExternalPooledBuffer
)

  
Public function Const FRDGBuffer * Finds an RDG buffer associated with the external buffer, or returns null if none is found.
Public function Const FRDGTexture *

FindExternalTexture ( IPooledRenderTarget* ExternalPooledTexture
)

  
Public function Const FRDGTexture * Finds an RDG texture associated with the external texture, or returns null if none is found.
Public function void Flushes all queued passes to an async task to perform setup work.
Public function Const const TRefCountPtr< FRDGPooledBuffer > &  
Public function Const const TRefCountPtr< IPooledRenderTarget > & Performs an immediate query for the underlying pooled resource.
Public function Static bool  
Public function Static bool  
Public function Static bool Whether RDG is running in immediate mode.
Public function Const bool Whether RDG will launch async tasks when AddSetup{CommandList}Task is called.
Public function void

QueueBufferExtraction ( FRDGBufferRef Buffer,
TRefCountPtr< FRDGPooledBuffer >* OutPooledBufferPtr,
ERHIAccess AccessFinal
)

  
Public function void Queues a pooled buffer extraction to happen at the end of graph execution.
Public function void

QueueBufferUpload ( FRDGBufferRef Buffer,
FRDGBufferInitialDataFillCallback&& InitialDataFillCallback
)

 A variant where the buffer is mapped and the pointer / size is provided to the callback to fill the buffer pointer.
Public function void

QueueBufferUpload ( FRDGBufferRef Buffer,
TArrayView< ElementType, int32 > Container,
FRDGBufferInitialDataFreeCallback&& InitialDataFreeCallback
)

  
Public function void

QueueBufferUpload ( FRDGBufferRef Buffer,
TArrayView< ElementType, int32 > Container,
ERDGInitialDataFlags InitialDataFlags
)

  
Public function void

QueueBufferUpload ( FRDGBufferRef Buffer,
FRDGBufferInitialDataCallback&& InitialDataCallback,
FRDGBufferInitialDataSizeCallback&& InitialDataSizeCallback,
FRDGBufferInitialDataFreeCallback&& InitialDataFreeCallback
)

  
Public function void

QueueBufferUpload ( FRDGBufferRef Buffer,
const void* InitialData,
uint64 InitialDataSize,
ERDGInitialDataFlags InitialDataFlags
)

 Queues a buffer upload operation prior to execution.
Public function void

QueueBufferUpload ( FRDGBufferRef Buffer,
FRDGBufferInitialDataCallback&& InitialDataCallback,
FRDGBufferInitialDataSizeCallback&& InitialDataSizeCallback
)

 A variant where InitialData and InitialDataSize are supplied through callbacks.
Public function void

QueueBufferUpload ( FRDGBufferRef Buffer,
const void* InitialData,
uint64 InitialDataSize,
FRDGBufferInitialDataFreeCallback&& InitialDataFreeCallback
)

 Queues a buffer upload operation prior to execution.
Public function void

QueueCommitReservedBuffer ( FRDGBufferRef Buffer,
uint64 CommitSizeInBytes
)

 Queues a reserved buffer commit on first use of the buffer in the graph.
Public function void Queues a pooled render target extraction to happen at the end of graph execution.
Public function void  
Public function FRDGBufferRef

RegisterExternalBuffer ( const TRefCountPtr< FRDGPooledBuffer >& ExternalPooledBuffer,
ERDGBufferFlags Flags,
ERHIAccess AccessFinal
)

  
Public function FRDGBufferRef

RegisterExternalBuffer ( const TRefCountPtr< FRDGPooledBuffer >& ExternalPooledBuffer,
ERDGBufferFlags Flags
)

 Register a external buffer to be tracked by the render graph.
Public function FRDGBufferRef

RegisterExternalBuffer ( const TRefCountPtr< FRDGPooledBuffer >& ExternalPooledBuffer,
const TCHAR* NameIfNotRegistered,
ERDGBufferFlags Flags
)

 Register an external buffer with a custom name.
Public function FRDGTextureRef

RegisterExternalTexture ( const TRefCountPtr< IPooledRenderTarget >& ExternalPooledTexture,
ERDGTextureFlags Flags
)

 Registers a external pooled render target texture to be tracked by the render graph.
Public function FRDGTextureRef

RegisterExternalTexture ( const TRefCountPtr< IPooledRenderTarget >& ExternalPooledTexture,
const TCHAR* NameIfNotRegistered,
ERDGTextureFlags Flags
)

 Register an external texture with a custom name.
Public function void  
Public function void Flag a resource that is produced by a pass but never used or extracted to not emit an 'unused' warning.
Public function void (External | Extracted only) Sets the access to transition to after execution at the end of the graph.
Public function void Sets the current command list stat for all subsequent passes.
Public function void Tells the builder to delete unused RHI resources.
Public function void

SetPassWorkload ( FRDGPass* Pass,
uint32 Workload
)

 Sets the expected workload of the pass execution lambda.
Public function void (External | Extracted only) Sets the access to transition to after execution at the end of the graph.
Public function Static void Per-frame update of the render graph resource pool.
Public function void

UseExternalAccessMode ( FRDGViewableResource* Resource,
ERHIAccess ReadOnlyAccess,
ERHIPipeline Pipelines
)

 Configures the resource for external access for all subsequent passes, or until UseInternalAccessMode is called.
Public function void

UseExternalAccessMode ( TArrayView< FRDGViewableResource*const > Resources,
ERHIAccess ReadOnlyAccess,
ERHIPipeline Pipelines
)

  
Public function void Use this method to resume tracking of a resource after calling UseExternalAccessMode.
Public function void  
Public function Static void Waits for the last RDG async delete task that was launched.

Typedefs

Name Description
FCollectResourceOpArray  

Constants

Name Description
kDefaultUnaccountedCSVStat  

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