Files
UnrealEngine/Engine/Source/Developer/DerivedDataCache/Private/DerivedDataValue.cpp
2025-05-18 13:04:45 +08:00

95 lines
2.8 KiB
C++

// Copyright Epic Games, Inc. All Rights Reserved.
#include "DerivedDataValue.h"
#include "Compression/OodleDataCompression.h"
#include "Containers/StringConv.h"
#include "Hash/xxhash.h"
#include "Misc/ByteSwap.h"
#include "Serialization/CompactBinary.h"
#include "Serialization/CompactBinarySerialization.h"
#include "Serialization/CompactBinaryWriter.h"
#include "Templates/UnrealTemplate.h"
namespace UE::DerivedData
{
constexpr ECompressedBufferCompressor GDefaultCompressor = ECompressedBufferCompressor::Mermaid;
constexpr ECompressedBufferCompressionLevel GDefaultCompressionLevel = ECompressedBufferCompressionLevel::VeryFast;
FValue FValue::Compress(const FCompositeBuffer& Buffer, const uint64 BlockSize)
{
return FValue(FCompressedBuffer::Compress(Buffer, GDefaultCompressor, GDefaultCompressionLevel, BlockSize));
}
FValue FValue::Compress(const FSharedBuffer& Buffer, const uint64 BlockSize)
{
return FValue(FCompressedBuffer::Compress(Buffer, GDefaultCompressor, GDefaultCompressionLevel, BlockSize));
}
FValueId::FValueId(const FMemoryView Id)
{
checkf(Id.GetSize() == sizeof(ByteArray),
TEXT("FValueId cannot be constructed from a view of %" UINT64_FMT " bytes."), Id.GetSize());
FMemory::Memcpy(Bytes, Id.GetData(), sizeof(ByteArray));
}
FValueId::FValueId(const FCbObjectId& Id)
: FValueId(ImplicitConv<const ByteArray&>(Id))
{
}
FValueId::operator FCbObjectId() const
{
return FCbObjectId(GetBytes());
}
FValueId FValueId::FromHash(const FIoHash& Hash)
{
checkf(!Hash.IsZero(), TEXT("FValueId requires a non-zero hash."));
return FValueId(MakeMemoryView(Hash.GetBytes()).Left(sizeof(ByteArray)));
}
FValueId FValueId::FromName(const FUtf8StringView Name)
{
checkf(!Name.IsEmpty(), TEXT("FValueId requires a non-empty name."));
uint8 HashBytes[16];
FXxHash128::HashBuffer(Name.GetData(), Name.Len()).ToByteArray(HashBytes);
return FValueId(MakeMemoryView(HashBytes, sizeof(ByteArray)));
}
FValueId FValueId::FromName(const FWideStringView Name)
{
return FValueId::FromName(FTCHARToUTF8(Name));
}
FValueId FValueId::MakeIndexed(int32 Index) const
{
alignas(int32) ByteArray IndexedBytes;
// Copy the prefix from this ID.
FMemoryView Prefix = MakeMemoryView(Bytes).Left(sizeof(ByteArray) - sizeof(int32));
FMutableMemoryView IndexView = MakeMemoryView(IndexedBytes).CopyFrom(Prefix);
// Copy the index as big endian to ensure an indexed ID is sorted by index.
*(int32*)IndexView.GetData() = NETWORK_ORDER32(Index);
return FValueId(IndexedBytes);
}
FCbWriter& operator<<(FCbWriter& Writer, const FValueId& Id)
{
Writer.AddObjectId(Id);
return Writer;
}
bool LoadFromCompactBinary(FCbFieldView Field, FValueId& OutId)
{
if (const FCbObjectId ObjectId = Field.AsObjectId(); !Field.HasError())
{
OutId = ObjectId;
return true;
}
OutId.Reset();
return false;
}
} // UE::DerivedData