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UnrealEngine/Engine/Source/Runtime/RenderCore/Public/VirtualTexturing.h
2025-05-18 13:04:45 +08:00

597 lines
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C++

// Copyright Epic Games, Inc. All Rights Reserved.
#pragma once
#include "Async/TaskGraphInterfaces.h"
#include "Containers/EnumAsByte.h"
#include "Containers/HashTable.h"
#include "CoreMinimal.h"
#include "Logging/LogMacros.h"
#include "Math/Color.h"
#include "Math/IntVector.h"
#include "Math/UnrealMathSSE.h"
#include "Misc/AssertionMacros.h"
#include "Misc/EnumClassFlags.h"
#include "PixelFormat.h"
#include "Stats/Stats.h"
#include "Templates/RefCounting.h"
#include "Templates/TypeHash.h"
#include "UObject/NameTypes.h"
class FRDGBuilder;
class FRHICommandListBase;
class FRHIShaderResourceView;
class FRHITexture;
class FRHIUnorderedAccessView;
struct IPooledRenderTarget;
class ISceneRenderer;
namespace ERHIFeatureLevel { enum Type : int; }
enum class EVTProducerPriority : uint8;
enum class EVTInvalidatePriority : uint8;
union FVirtualTextureProducerHandle
{
FVirtualTextureProducerHandle() : PackedValue(0u) {}
explicit FVirtualTextureProducerHandle(uint32 InPackedValue) : PackedValue(InPackedValue) {}
FVirtualTextureProducerHandle(uint32 InIndex, uint32 InMagic) : Index(InIndex), Magic(InMagic) {}
inline bool IsValid() const { return PackedValue != 0u; }
inline bool IsNull() const { return PackedValue == 0u; }
uint32 PackedValue;
struct
{
uint32 Index : 22;
uint32 Magic : 10;
};
friend inline bool operator==(const FVirtualTextureProducerHandle& Lhs, const FVirtualTextureProducerHandle& Rhs) { return Lhs.PackedValue == Rhs.PackedValue; }
friend inline bool operator!=(const FVirtualTextureProducerHandle& Lhs, const FVirtualTextureProducerHandle& Rhs) { return Lhs.PackedValue != Rhs.PackedValue; }
};
static_assert(sizeof(FVirtualTextureProducerHandle) == sizeof(uint32), "Bad packing");
/** Maximum number of layers that can be allocated in a single VT page table */
#define VIRTUALTEXTURE_SPACE_MAXLAYERS 8
/** Maximum dimension of VT page table texture */
#define VIRTUALTEXTURE_LOG2_MAX_PAGETABLE_SIZE 12u
#define VIRTUALTEXTURE_MAX_PAGETABLE_SIZE (1u << VIRTUALTEXTURE_LOG2_MAX_PAGETABLE_SIZE)
#define VIRTUALTEXTURE_MIN_PAGETABLE_SIZE 32u
/**
* Parameters needed to create an IAllocatedVirtualTexture
* Describes both page table and physical texture size, format, and layout
*/
struct FAllocatedVTDescription
{
FName Name;
uint32 TileSize = 0u;
uint32 TileBorderSize = 0u;
uint32 MaxSpaceSize = 0u;
uint32 IndirectionTextureSize = 0u;
uint8 Dimensions = 0u;
uint8 NumTextureLayers = 0u;
uint8 ForceSpaceID = 0xff;
uint8 AdaptiveLevelBias = 0u;
/** Producer for each texture layer. */
FVirtualTextureProducerHandle ProducerHandle[VIRTUALTEXTURE_SPACE_MAXLAYERS];
/** Local layer inside producer for each texture layer. */
uint8 ProducerLayerIndex[VIRTUALTEXTURE_SPACE_MAXLAYERS] = { 0u };
union
{
uint8 PackedFlags = 0u;
struct
{
/**
* Should the AllocatedVT create its own dedicated page table allocation? Can be useful to control total allocation.
* The system only supports a limited number of unique page tables, so this must be used carefully
*/
uint8 bPrivateSpace : 1;
/**
* If the AllocatedVT has the same producer mapped to multiple layers, should those be merged into a single page table layer?
* This can make for more efficient page tables when enabled, but certain code may make assumption that number of layers
* specified when allocating VT exactly matches the resulting page page
*/
uint8 bShareDuplicateLayers : 1;
};
};
friend inline bool operator==(const FAllocatedVTDescription& Lhs, const FAllocatedVTDescription& Rhs)
{
if (Lhs.TileSize != Rhs.TileSize ||
Lhs.TileBorderSize != Rhs.TileBorderSize ||
Lhs.Dimensions != Rhs.Dimensions ||
Lhs.NumTextureLayers != Rhs.NumTextureLayers ||
Lhs.PackedFlags != Rhs.PackedFlags)
{
return false;
}
for (uint32 LayerIndex = 0u; LayerIndex < Lhs.NumTextureLayers; ++LayerIndex)
{
if (Lhs.ProducerHandle[LayerIndex] != Rhs.ProducerHandle[LayerIndex] ||
Lhs.ProducerLayerIndex[LayerIndex] != Rhs.ProducerLayerIndex[LayerIndex])
{
return false;
}
}
return true;
}
friend inline bool operator!=(const FAllocatedVTDescription& Lhs, const FAllocatedVTDescription& Rhs)
{
return !operator==(Lhs, Rhs);
}
friend inline uint32 GetTypeHash(const FAllocatedVTDescription& Description)
{
uint32 Hash = GetTypeHash(Description.TileSize);
Hash = HashCombine(Hash, GetTypeHash(Description.TileBorderSize));
Hash = HashCombine(Hash, GetTypeHash(Description.Dimensions));
Hash = HashCombine(Hash, GetTypeHash(Description.NumTextureLayers));
Hash = HashCombine(Hash, GetTypeHash(Description.PackedFlags));
for (uint32 LayerIndex = 0u; LayerIndex < Description.NumTextureLayers; ++LayerIndex)
{
Hash = HashCombine(Hash, GetTypeHash(Description.ProducerHandle[LayerIndex].PackedValue));
Hash = HashCombine(Hash, GetTypeHash(Description.ProducerLayerIndex[LayerIndex]));
}
return Hash;
}
};
struct FVTProducerDescription
{
RENDERCORE_API FVTProducerDescription();
FName Name; /** Will be name of UTexture for streaming VTs, mostly here for debugging */
uint32 FullNameHash;
bool bPersistentHighestMip = true;
bool bContinuousUpdate = false;
bool bRequiresSinglePhysicalPool = false;
bool bNotifyCompleted = false; /** Producer will receive OnRequestsCompleted() callbacks every frame when enabled. */
uint32 TileSize = 0u;
uint32 TileBorderSize = 0u;
/**
* Producers are made up of a number of block, each block has uniform size, and blocks are arranged in a larger grid
* 'Normal' VTs will typically be a single block, for UDIM textures, blocks will map to individual UDIM texture sheets
* When multiple producers are allocated together, they will be aligned such that blocks of each layer overlay on top of each other
* Number of blocks for each layer may be different in this case, this is handled by wrapping blocks for layers with fewer blocks
*/
uint32 BlockWidthInTiles = 0u;
uint32 BlockHeightInTiles = 0u;
uint32 DepthInTiles = 0u;
uint16 WidthInBlocks = 1u;
uint16 HeightInBlocks = 1u;
uint8 Dimensions = 0u;
uint8 MaxLevel = 0u;
/**
* Producers will fill a number of texture layers.
* These texture layers can be distributed across one or more physical groups.
* Each physical group can contain one or more of the texture layers.
* Within a physical group the texture layers share the same UV allocation/mapping and can be referenced by a single page table lookup.
*/
uint8 NumTextureLayers = 0u;
TEnumAsByte<EPixelFormat> LayerFormat[VIRTUALTEXTURE_SPACE_MAXLAYERS] = { PF_Unknown };
FLinearColor LayerFallbackColor[VIRTUALTEXTURE_SPACE_MAXLAYERS] = { FLinearColor::Black };
bool bIsLayerSRGB[VIRTUALTEXTURE_SPACE_MAXLAYERS] = { false };
uint8 NumPhysicalGroups = 0u;
uint8 PhysicalGroupIndex[VIRTUALTEXTURE_SPACE_MAXLAYERS] = { 0 };
/** Priority allows to process a producer before another which increases responsiveness in high contention situations */
EVTProducerPriority Priority;
};
typedef void (FVTProducerDestroyedFunction)(const FVirtualTextureProducerHandle& InHandle, void* Baton);
/**
* A Finalizer is an object that does the final work of filling the physical textures.
* The work for all finalizers is scheduled at a specific point in the frame where we can write to the physical texture without hazards, and
* where the virtual texture page tables are also updated.
* The finalizer work may be split into two parts.
* RenderFinalize() does not write to the physical texture, but can read from virtual textures. This is a phase that allows any
* page rendering which may need to sample virtual textures. Runtime virtual textures and material systems require this.
* Finalise() must write to the physical textures, but cannot sample from them.
* All finalizers need to implement Finalize() but only ones that need to sample virtual textures need to implement RenderFinalize().
*/
class IVirtualTextureFinalizer
{
public:
/** Finalize work that has read only access to the virtual texture physical pools. */
virtual void RenderFinalize(FRDGBuilder& GraphBuilder, ISceneRenderer* SceneRenderingContext) {}
/** Finalize work that has write only access to the virtual texture physical pools. */
virtual void Finalize(FRDGBuilder& GraphBuilder) = 0;
};
enum class EVTRequestPageStatus
{
/** The request is invalid and no data will ever be available */
Invalid,
/**
* Requested data is not being produced, and a request can't be started as some part of the system is at capacity.
* Requesting the same data at a later time should succeed.
*/
Saturated,
/**
* Requested data is currently being produced, but is not yet ready.
* It's valid to produce this data, but doing so may block until data is ready.
*/
Pending,
/** Requested data is available */
Available,
};
/** Check to see there is data available (possibly requiring waiting) given the current status */
FORCEINLINE bool VTRequestPageStatus_HasData(EVTRequestPageStatus InStatus) { return InStatus == EVTRequestPageStatus::Pending || InStatus == EVTRequestPageStatus::Available; }
enum class EVTRequestPagePriority
{
Normal,
High,
};
enum class EVTProducePageFlags : uint8
{
None = 0u,
SkipPageBorders = (1u << 0),
ContinuousUpdate = (1u << 1),
};
ENUM_CLASS_FLAGS(EVTProducePageFlags);
struct FVTRequestPageResult
{
FVTRequestPageResult(EVTRequestPageStatus InStatus = EVTRequestPageStatus::Invalid, uint64 InHandle = 0u) : Handle(InHandle), Status(InStatus) {}
/** Opaque handle to the request, must be passed to 'ProducePageData'. Only valid if status is Pending/Available */
uint64 Handle;
/** Status of the request */
EVTRequestPageStatus Status;
};
/** Describes a location to write a single layer of a VT tile */
struct FVTProduceTargetLayer
{
/** Pooled render target to write to. */
IPooledRenderTarget* PooledRenderTarget = nullptr;
/** Location within the target texture to write. */
FIntVector pPageLocation = FIntVector::ZeroValue;
UE_DEPRECATED(5.6, "Use PooledRenderTarget instead.")
FRHITexture* TextureRHI = nullptr;
// Disable some TextureRHI deprecation warnings here.
PRAGMA_DISABLE_DEPRECATION_WARNINGS
FVTProduceTargetLayer() = default;
FVTProduceTargetLayer(const FVTProduceTargetLayer&) = default;
FVTProduceTargetLayer& operator=(const FVTProduceTargetLayer&) = default;
PRAGMA_ENABLE_DEPRECATION_WARNINGS
};
/**
* This is the interface that can produce tiles of virtual texture data
* This can be extended to represent different ways of generating VT, such as disk streaming, runtime compositing, or whatever
* It's provided to the renderer module
*/
class IVirtualTexture
{
public:
inline IVirtualTexture() {}
virtual ~IVirtualTexture() {}
/**
* Gives a localized mip bias for the given local vAddress.
* This is used to implement sparse VTs, the bias is number of mip levels to add to reach a resident page
* Must be thread-safe, may be called from any thread
* @param vLevel The mipmap level to check
* @param vAddress Virtual address to check
* @return Mip bias to be added to vLevel to reach a resident page at the given address
*/
virtual uint32 GetLocalMipBias(uint8 vLevel, uint32 vAddress) const { return 0u; }
/**
* Whether data for the given page is streamed (e.g. loading from disk).
*/
virtual bool IsPageStreamed(uint8 vLevel, uint32 vAddress) const = 0;
/**
* Makes a request for the given page data.
* For data sources that can generate data immediately, it's reasonable for this method to do nothing, and simply return 'Available'
* Only called from render thread
* @param ProducerHandle Handle to this producer, can be used as a UID for this producer for any internal caching mechanisms
* @param LayerMask Mask of requested layers
* @param vLevel The mipmap level of the data
* @param vAddress Bit-interleaved x,y page indexes
* @param Priority Priority of the request, used to drive async IO/task priority needed to generate data for request
* @return FVTRequestPageResult describing the availability of the request
*/
virtual FVTRequestPageResult RequestPageData(FRHICommandListBase& RHICmdList, const FVirtualTextureProducerHandle& ProducerHandle, uint8 LayerMask, uint8 vLevel, uint64 vAddress, EVTRequestPagePriority Priority) = 0;
/**
* Upload page data to the cache, data must have been previously requested, and reported either 'Available' or 'Pending'
* The system will attempt to call RequestPageData/ProducePageData only once for a given vLevel/vAddress, with all the requested layers set in LayerMask,
* this is important for certain types of procedural producers that may generate multiple layers of VT data at the same time
* It's valid to produce 'Pending' page data, but in this case ProducePageData may block until data is ready
* Only called from render thread
* @param RHICmdList Used to write any commands required to generate the VT page data
* @param FeatureLevel The current RHI feature level
* @param ProducerHandle Handle to this producer
* @param LayerMask Mask of requested layers; can be used to only produce data for these layers as an optimization, or ignored if all layers are logically produced together
* @param vLevel The mipmap level of the data
* @param vAddress Bit-interleaved x,y page indexes
* @param RequestHandle opaque handle returned from 'RequestPageData'
* @param TargetLayers Array of 'FVTProduceTargetLayer' structs, gives location where each layer should write data
* @return a 'IVirtualTextureFinalizer' which must be finalized to complete the operation
*/
virtual IVirtualTextureFinalizer* ProducePageData(
FRHICommandListBase& RHICmdList,
ERHIFeatureLevel::Type FeatureLevel,
EVTProducePageFlags Flags,
const FVirtualTextureProducerHandle& ProducerHandle, uint8 LayerMask, uint8 vLevel, uint64 vAddress,
uint64 RequestHandle,
const FVTProduceTargetLayer* TargetLayers) = 0;
/** Collect all task graph events. */
virtual void GatherProducePageDataTasks(FVirtualTextureProducerHandle const& ProducerHandle, FGraphEventArray& InOutTasks) const {}
/** Collect all task graph events related to a request. */
virtual void GatherProducePageDataTasks(uint64 RequestHandle, FGraphEventArray& InOutTasks) const {};
/** Dump any type specific debug info. */
virtual void DumpToConsole(bool verbose) {}
/** Called on every virtual texture system update once all requests are completed, if bNotifyCompleted is enabled. */
virtual void OnRequestsCompleted() {}
};
enum class EVTPageTableFormat : uint8
{
UInt16,
UInt32,
};
/**
* This interface represents a chunk of VT data allocated and owned by the renderer module, backed by both a page table texture, and a physical texture cache for each layer.
* Both page table and physical texture may be shared amongst many different allocated virtual textures.
* Any method that deals with physical texture requires an explicit LayerIndex parameter to identify the physical texture in question,
* methods that don't have LayerIndex parameter refer to properties shared by all textures using the given page table
* These are created with IRendererModule::AllocateVirtualTexture, and destroyed with IRendererModule::DestroyVirtualTexture
* They must be allocated from render thread, but may be destroyed from any thread
*/
class IAllocatedVirtualTexture
{
public:
static const uint32 LayersPerPageTableTexture = 4u;
inline IAllocatedVirtualTexture(const FAllocatedVTDescription& InDesc,
uint32 InBlockWidthInTiles,
uint32 InBlockHeightInTiles,
uint32 InWidthInBlocks,
uint32 InHeightInBlocks,
uint32 InDepthInTiles)
: Description(InDesc)
, BlockWidthInTiles(InBlockWidthInTiles)
, BlockHeightInTiles(InBlockHeightInTiles)
, WidthInBlocks(InWidthInBlocks)
, HeightInBlocks(InHeightInBlocks)
, DepthInTiles(InDepthInTiles)
, FrameDeleted(0u)
, NumRefs(0)
, bIsWaitingToMap(false)
, PageTableFormat(EVTPageTableFormat::UInt32)
, SpaceID(~0u)
, MaxLevel(0u)
, VirtualAddress(~0u)
, VirtualPageX(~0u)
, VirtualPageY(~0u)
{}
virtual uint32 GetPersistentHash() const = 0;
virtual uint32 GetNumPageTableTextures() const = 0;
virtual FRHITexture* GetPageTableTexture(uint32 InPageTableIndex) const = 0;
virtual FRHITexture* GetPageTableIndirectionTexture() const = 0;
virtual uint32 GetPhysicalTextureSize(uint32 InLayerIndex) const = 0;
virtual FRHITexture* GetPhysicalTexture(uint32 InLayerIndex) const = 0;
virtual FRHIShaderResourceView* GetPhysicalTextureSRV(uint32 InLayerIndex, bool bSRGB) const = 0;
/** Writes 2x FUintVector4 */
virtual void GetPackedPageTableUniform(FUintVector4* OutUniform) const = 0;
/** Writes 1x FUintVector4 */
virtual void GetPackedUniform(FUintVector4* OutUniform, uint32 LayerIndex) const = 0;
virtual void DumpToConsole(bool bVerbose) const {}
inline const FAllocatedVTDescription& GetDescription() const { return Description; }
inline const FVirtualTextureProducerHandle& GetProducerHandle(uint32 InLayerIndex) const { check(InLayerIndex < Description.NumTextureLayers); return Description.ProducerHandle[InLayerIndex]; }
inline uint32 GetVirtualTileSize() const { return Description.TileSize; }
inline uint32 GetTileBorderSize() const { return Description.TileBorderSize; }
inline uint32 GetPhysicalTileSize() const { return Description.TileSize + Description.TileBorderSize * 2u; }
inline uint32 GetNumTextureLayers() const { return Description.NumTextureLayers; }
inline uint8 GetDimensions() const { return Description.Dimensions; }
inline uint32 GetWidthInBlocks() const { return WidthInBlocks; }
inline uint32 GetHeightInBlocks() const { return HeightInBlocks; }
inline uint32 GetBlockWidthInTiles() const { return BlockWidthInTiles; }
inline uint32 GetBlockHeightInTiles() const { return BlockHeightInTiles; }
inline uint32 GetWidthInTiles() const { return BlockWidthInTiles * WidthInBlocks; }
inline uint32 GetHeightInTiles() const { return BlockHeightInTiles * HeightInBlocks; }
inline uint32 GetDepthInTiles() const { return DepthInTiles; }
inline uint32 GetWidthInPixels() const { return GetWidthInTiles() * Description.TileSize; }
inline uint32 GetHeightInPixels() const { return GetHeightInTiles() * Description.TileSize; }
inline uint32 GetDepthInPixels() const { return DepthInTiles * Description.TileSize; }
inline uint32 GetSpaceID() const { return SpaceID; }
inline uint32 GetVirtualAddress() const { return VirtualAddress; }
inline uint32 GetVirtualPageX() const { return VirtualPageX; }
inline uint32 GetVirtualPageY() const { return VirtualPageY; }
inline uint32 GetMaxLevel() const { return MaxLevel; }
inline EVTPageTableFormat GetPageTableFormat() const { return PageTableFormat; }
protected:
friend class FVirtualTextureSystem;
virtual void Destroy(class FVirtualTextureSystem* InSystem) = 0;
virtual bool TryMapLockedTiles(class FVirtualTextureSystem* InSystem) const = 0;
virtual ~IAllocatedVirtualTexture() {}
FAllocatedVTDescription Description;
uint32 BlockWidthInTiles;
uint32 BlockHeightInTiles;
uint32 WidthInBlocks;
uint32 HeightInBlocks;
uint32 DepthInTiles;
uint32 FrameDeleted;
int32 NumRefs;
bool bIsWaitingToMap;
// should be set explicitly by derived class constructor
EVTPageTableFormat PageTableFormat;
uint32 SpaceID;
uint32 MaxLevel;
uint32 VirtualAddress;
uint32 VirtualPageX;
uint32 VirtualPageY;
};
/**
* Interface for adaptive virtual textures.
* This manages multiple allocated virtual textures in a space to simulate a single larger virtual texture.
*/
class IAdaptiveVirtualTexture
{
public:
/** Get the persistent allocated virtual texture for low mips from the adaptive virtual texture. */
virtual IAllocatedVirtualTexture* GetAllocatedVirtualTexture() = 0;
protected:
friend class FVirtualTextureSystem;
virtual ~IAdaptiveVirtualTexture() {}
virtual int32 GetSpaceID() const = 0;
virtual void Destroy(class FVirtualTextureSystem* InSystem) = 0;
};
/** Describes an adaptive virtual texture. */
struct FAdaptiveVTDescription
{
uint32 TileCountX;
uint32 TileCountY;
uint32 MaxAdaptiveLevel;
};
/**
* Identifies a VT tile within a given producer
*/
union FVirtualTextureLocalTile
{
inline FVirtualTextureLocalTile() {}
explicit inline FVirtualTextureLocalTile(const FVirtualTextureProducerHandle& InProducerHandle, uint32 InLocal_vAddress, uint8 InLocal_vLevel)
: PackedProducerHandle(InProducerHandle.PackedValue)
, Local_vAddress(InLocal_vAddress)
, Local_vLevel(InLocal_vLevel)
, Pad(0)
{
}
explicit inline FVirtualTextureLocalTile(uint64 InPackedValue)
: PackedValue(InPackedValue)
{
Pad = 0;
}
inline FVirtualTextureProducerHandle GetProducerHandle() const { return FVirtualTextureProducerHandle(PackedProducerHandle); }
uint64 PackedValue = 0;
struct
{
// Core "identity" data that identify a given tile
uint32 PackedProducerHandle;
uint32 Local_vAddress : 24;
uint32 Local_vLevel : 4;
uint32 Pad : 4; // Important : this has to be kept in sync with FVirtualTextureLocalTileRequest : both are packed in a uint64 and the latter stores additional info in these bits
};
friend inline bool operator==(const FVirtualTextureLocalTile& Lhs, const FVirtualTextureLocalTile& Rhs) { return Lhs.PackedValue == Rhs.PackedValue; }
friend inline bool operator!=(const FVirtualTextureLocalTile& Lhs, const FVirtualTextureLocalTile& Rhs) { return Lhs.PackedValue != Rhs.PackedValue; }
friend inline uint32 GetTypeHash(const FVirtualTextureLocalTile& T) { return GetTypeHash(T.PackedValue); }
inline uint16 GetMurmurHash() const { return static_cast<uint16>(MurmurFinalize64(PackedValue)); }
};
static_assert(sizeof(FVirtualTextureLocalTile) == sizeof(uint64), "Bad packing");
/**
* Identifies a VT tile request : a VT tile, along with priority information for processing this request
*/
union FVirtualTextureLocalTileRequest
{
explicit inline FVirtualTextureLocalTileRequest() {}
explicit inline FVirtualTextureLocalTileRequest(const FVirtualTextureLocalTile& InTile, EVTProducerPriority InProducerPriority, EVTInvalidatePriority InInvalidatePriority)
: TilePackedValue(InTile.PackedValue)
, ProducerPriority(static_cast<uint64>(InProducerPriority))
, InvalidatePriority(static_cast<uint64>(InInvalidatePriority))
{
checkSlow(InTile == GetTile());
ValidatePriorities();
}
inline FVirtualTextureLocalTile GetTile() const { return FVirtualTextureLocalTile(TilePackedValue); }
inline EVTProducerPriority GetProducerPriority() const { return static_cast<EVTProducerPriority>(ProducerPriority); }
inline EVTInvalidatePriority GetInvalidatePriority() const { return static_cast<EVTInvalidatePriority>(InvalidatePriority); }
inline FVirtualTextureLocalTileRequest& MergeWith(const FVirtualTextureLocalTileRequest& InOther)
{
// Keep the highest priorities of the 2 :
ProducerPriority = FMath::Max(ProducerPriority, InOther.ProducerPriority);
InvalidatePriority = FMath::Max(InvalidatePriority, InOther.InvalidatePriority);
checkSlow(*this == InOther);
checkSlow(GetTile() == InOther.GetTile());
ValidatePriorities();
return *this;
}
uint64 PackedValue;
struct
{
// Core "identity" data that identifies a given tile :
uint64 TilePackedValue : 60;
// Additional data about the request :
uint64 ProducerPriority : 3; // See EVTProducerPriority
uint64 InvalidatePriority : 1; // Indicates whether the tile should get prioritized over others
};
friend inline bool operator==(const FVirtualTextureLocalTileRequest& Lhs, const FVirtualTextureLocalTileRequest& Rhs) { return Lhs.GetIdentity() == Rhs.GetIdentity(); }
friend inline bool operator!=(const FVirtualTextureLocalTileRequest& Lhs, const FVirtualTextureLocalTileRequest& Rhs) { return Lhs.GetIdentity() != Rhs.GetIdentity(); }
friend inline uint32 GetTypeHash(const FVirtualTextureLocalTileRequest& T) { return GetTypeHash(T.GetIdentity()); }
inline uint64 GetIdentity() const { return TilePackedValue; } // 2 requests from the same tile are considered identical (it's up to the user to "merge" them if necessary)
inline uint16 GetMurmurHash() const { return static_cast<uint16>(MurmurFinalize64(GetIdentity())); }
private:
RENDERCORE_API void ValidatePriorities() const;
};
static_assert(sizeof(FVirtualTextureLocalTileRequest) == sizeof(uint64), "Bad packing");
/**
* Helper function that tries to add a new FVirtualTextureLocalTileRequest to a TSet but, in case this tile is already in the set, merges it with the existing request :
*/
inline FVirtualTextureLocalTileRequest& AddOrMergeTileRequest(const FVirtualTextureLocalTileRequest& InTileRequest, TSet<FVirtualTextureLocalTileRequest>& TileRequests)
{
bool bAlreadyInSet = false;
FVirtualTextureLocalTileRequest& Result = TileRequests.FindOrAdd(InTileRequest, &bAlreadyInSet);
if (bAlreadyInSet)
{
// If the request already exists, merge with this new request, to keep the highest priority :
Result.MergeWith(InTileRequest);
}
return Result;
}
RENDERCORE_API DECLARE_LOG_CATEGORY_EXTERN(LogVirtualTexturing, Log, All);
DECLARE_STATS_GROUP(TEXT("Virtual Texturing"), STATGROUP_VirtualTexturing, STATCAT_Advanced);
DECLARE_STATS_GROUP(TEXT("Virtual Texture Memory"), STATGROUP_VirtualTextureMemory, STATCAT_Advanced);