82 lines
2.2 KiB
C++
82 lines
2.2 KiB
C++
// Copyright Epic Games, Inc. All Rights Reserved.
|
|
|
|
#pragma once
|
|
|
|
#include "CoreTypes.h"
|
|
#include "Misc/AssertionMacros.h"
|
|
#include "HAL/UnrealMemory.h"
|
|
#include "Serialization/Archive.h"
|
|
#include "Serialization/BulkData.h"
|
|
#include "Containers/UnrealString.h"
|
|
|
|
/**
|
|
* Custom archive class for writing directly to bulk data.
|
|
*/
|
|
class FBulkDataWriter final: public FArchive
|
|
{
|
|
public:
|
|
FBulkDataWriter(FByteBulkData& InBulkData, bool bIsPersistent = false)
|
|
: BulkData(InBulkData), WriterPos(BulkData.GetBulkDataSize()), WriterSize(WriterPos)
|
|
{
|
|
SetIsSaving(true);
|
|
SetIsPersistent(bIsPersistent);
|
|
Buffer = BulkData.Lock(LOCK_READ_WRITE);
|
|
}
|
|
|
|
~FBulkDataWriter()
|
|
{
|
|
// Remove the slack from the allocated bulk data
|
|
BulkData.Realloc(WriterSize);
|
|
BulkData.Unlock();
|
|
}
|
|
|
|
virtual void Serialize(void* Data, int64 Num)
|
|
{
|
|
// Determine if we need to reallocate the buffer to fit the next item
|
|
const int64 NewPos = WriterPos + Num;
|
|
check(NewPos >= WriterPos);
|
|
if (NewPos > BulkData.GetBulkDataSize())
|
|
{
|
|
// If so, resize to the new size + 3/8
|
|
Buffer = BulkData.Realloc(NewPos + 3 * NewPos / 8 + 16);
|
|
}
|
|
|
|
FMemory::Memcpy(static_cast<unsigned char*>(Buffer) + WriterPos, Data, Num);
|
|
WriterPos += Num;
|
|
WriterSize = FMath::Max(WriterSize, WriterPos);
|
|
}
|
|
|
|
using FArchive::operator<<; // For visibility of the overloads we don't override
|
|
|
|
virtual FArchive& operator<<(class FName& Name) override
|
|
{
|
|
// FNames are serialized as strings in BulkData
|
|
FString StringName = Name.ToString();
|
|
*this << StringName;
|
|
return *this;
|
|
}
|
|
|
|
virtual int64 Tell() { return WriterPos; }
|
|
virtual int64 TotalSize() { return WriterSize; }
|
|
|
|
virtual void Seek(int64 InPos)
|
|
{
|
|
check(InPos >= 0);
|
|
check(InPos <= WriterSize);
|
|
WriterPos = InPos;
|
|
}
|
|
|
|
virtual bool AtEnd()
|
|
{
|
|
return WriterPos >= WriterSize;
|
|
}
|
|
|
|
virtual FString GetArchiveName() const { return TEXT("FBulkDataWriter"); }
|
|
|
|
protected:
|
|
FByteBulkData& BulkData;
|
|
void* Buffer;
|
|
int64 WriterPos;
|
|
int64 WriterSize;
|
|
};
|