Stream huge TArray to textfile

[Lolukok]

@henryLiu

Glad to know some one here working with point cloud as well.

Nice to meet someone, that knows the struggle

@henryLiu

In this case, SaveStringArrayToFile may not suit for handling huge size of array, since that is 32 bits version and be limited by max length of FString which is int32.

Hope the code like below could help.

#include "FileManager.h"
void UMyBlueprintFunctionLibrary::WriteExcerptDataIntoFile(FString FileSource, TArray<FVector> InExcerptData)
{
FText CheckoutFailReason;
bool bNewFile = true;
bool bCheckoutOrAddSucceeded = true;
if (FPaths::FileExists(FileSource))
{
// Check out the existing file
bNewFile = false;
}

FArchive* FileWriter = IFileManager::Get().CreateFileWriter(*FileSource, EFileWrite::FILEWRITE_Append | EFileWrite::FILEWRITE_AllowRead | EFileWrite::FILEWRITE_EvenIfReadOnly);

if (bNewFile)
{
FString FileHeader;
FileHeader += "Start Recording:";
FileHeader += LINE_TERMINATOR;

FileWriter->Serialize(TCHAR_TO_ANSI(*FileHeader), FileHeader.Len());
}
else
{
FileWriter->Seek(FMath::Max(FileWriter->TotalSize(), (int64)0));
}

int TotalNum = InExcerptData.Num();
int Count = 0;
int StepNum = 100;
while (Count < TotalNum)
{
FString NewExcerpt;
for (int i = 0; i < StepNum; i++)
{
FVector& Vec = InExcerptData[Count];
NewExcerpt += FString::Printf(TEXT("Vec:%f,%f,%f
"), Vec.X, Vec.Y, Vec.Z);
Count++;
}
FileWriter->Serialize(TCHAR_TO_ANSI(*NewExcerpt), NewExcerpt.Len());
}

FileWriter->Close();
delete FileWriter;
return;
}

Thank you, I will give that a test run later!