Can't get data back to game thread

Development Programming & Scripting C++
1

This just crashes at ANetworkRec().EmptyFunction(IncomingVector); It is at the bottom but everything seemed to be working.

no idea how to pass data between threads
no idea how to call functions from another blueprint
no idea what to google for either of these… it usually just returns that blueprints that are not in c++


// Fill out your copyright notice in the Description page of Project Settings.
#include <iostream>
#include <stdio.h>
#include <WS2tcpip.h>
#include <tchar.h>
#include "EngineUtils.h"
#include "Engine/World.h"
#include <string>

using namespace std;

// Include the Winsock library (lib) file
#pragma comment (lib, "ws2_32.lib")

#include "NetworkRec.h"

TCHAR GetBuf[1024];
FVector ReturnedVector;

ANetworkRec::ANetworkRec()
{
    PrimaryActorTick.bCanEverTick = true;

}

void ANetworkRec::BeginPlay()
{
    Super::BeginPlay();
    RunPrimeTask();
}

void ANetworkRec::Tick(float DeltaTime)
{
    Super::Tick(DeltaTime);
    //GetActors();

}

void ANetworkRec::RunPrimeTask()
{
    (new FAutoDeleteAsyncTask<NewPrimeSearchTask>())->StartBackgroundTask();
}

void ANetworkRec::FindActors(FVector NewRotation)
{
    for (AActor* Actor : TActorRange<AActor>(GetWorld()))
    {
        if (Actor && Actor->ActorHasTag("NetworkedPlayer"))
        {
            //ApplyToActors(NewRotation, Actor);
        }
    }
}

void ANetworkRec::EmptyFunction(FVector idkwhat)
{
    UE_LOG(LogTemp, Warning, TEXT("empty"));
}

//============

NewPrimeSearchTask::NewPrimeSearchTask()
{
}
//destructor used for manual memory cleaning for things outside ue4 scope
//gets called by FAutoDeleteAsync
NewPrimeSearchTask::~NewPrimeSearchTask()
{
    UE_LOG(LogTemp, Warning, TEXT("Task finished"));
}

void NewPrimeSearchTask::DoWork()
{

    WSADATA data;
    WORD version = MAKEWORD(2, 2);

    // Start WinSock
    int wsOk = WSAStartup(version, &data);
    if (wsOk != 0)
    {
        UE_LOG(LogTemp, Warning, TEXT("Can't start Winsock! %i"), wsOk);
        return;
    }

    SOCKET in = socket(AF_INET, SOCK_DGRAM, 0);

    // Create a server hint structure for the server
    sockaddr_in serverHint;
    serverHint.sin_addr.S_un.S_addr = ADDR_ANY; // Us any IP address available on the machine
    serverHint.sin_family = AF_INET; // Address format is IPv4
    //debug to display port for checking on netstat
    u_short PortNumber = 12773; //catch
    int PortNumberInt = (int)PortNumber;
    serverHint.sin_port = htons(PortNumber); // Convert from little to big endian

    // Try and bind the socket to the IP and port
    if (bind(in, (sockaddr*)&serverHint, sizeof(serverHint)) == SOCKET_ERROR)
    {
        UE_LOG(LogTemp, Warning, TEXT("Can't bind socket! Attempting to close. Error code %i 
"), WSAGetLastError());
        closesocket(in);
        WSACleanup();
        UE_LOG(LogTemp, Warning, TEXT("Tried to close socket %i"), PortNumberInt);
        if (bind(in, (sockaddr*)&serverHint, sizeof(serverHint)) == SOCKET_ERROR)
        {
            UE_LOG(LogTemp, Warning, TEXT("Socket still in use or not opened, wsacleanup might need to rebuild something.... idk aborting"));
            return;
        }
    }

    sockaddr_in client; // Use to hold the client information (port / ip address)
    int clientLength = sizeof(client); // The size of the client information

    char buf[1024];
    for (int p = 10; p > 1; p++)
    {
        //UE_LOG(LogTemp, Warning, TEXT("listening..."));
        ZeroMemory(&client, clientLength); // Clear the client structure
        ZeroMemory(buf, 1024); // Clear the receive buffer

        // Wait for message
        int bytesIn = recvfrom(in, buf, 1024, 0, (sockaddr*)&client, &clientLength);
        if (bytesIn == SOCKET_ERROR)
        {
            UE_LOG(LogTemp, Warning, TEXT("Error receiving from client %i"), WSAGetLastError());
            continue;
        }

        // Display message and client info
        char clientIp[256]; // Create enough space to convert the address byte array
        ZeroMemory(clientIp, 256); // to string of characters

        // Convert from byte array to chars
        inet_ntop(AF_INET, &client.sin_addr, clientIp, 256);
        // Display the message / who sent it
        NewPrimeSearchTask::ConvertMessage(buf);
        //UE_LOG(LogTemp, Log, TEXT("%s"), UTF8_TO_TCHAR(buf));
    }
}

void NewPrimeSearchTask::ConvertMessage(char buf[1024])
{
    FVector IncomingVector;
    char CheckJoinMsg] = "serverjoin";
    if (strcmp(buf, CheckJoinMsg) == 0)
    {
        UE_LOG(LogTemp, Warning, TEXT("serverjin found, changing to 0s"));
        IncomingVector = FVector(0.f, 0.f, 0.f);
    }
    else
    {
        IncomingVector.InitFromString(buf);
    }
    ReturnedVector = IncomingVector;
    ANetworkRec().EmptyFunction(IncomingVector);
}
2

You can’t call Actor’s constructor like that.
You are supposed to spawn an actor in game world using a Spawn<>() function. Learn the engine’s game framework.

You cannot modify Actor’s property data (such as actor location) from another thread either. You should request the game thread to make the change for your alien thread instead.
Search engine source code for “ENamedThreads::GameThread” for practical examples.

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