I’ve started from the Unreal example of flying in c++. I’ve added some classes to the project, but when I press play the UE Editor crashes even if I remove the newly added classes. I attach the log
I don’t see any crash from the log file. Are you sure this is the right one?
Looks like a null pointer exception. Double check/debug these two functions:
[Callstack] 0x00000000C6941FB0 UE4Editor-Drone_follower.dll!AActorsController::ReturnNewData() [c:\users\4r35\documents\unreal projects\drone_follower\source\drone_follower\actorscontroller.cpp:42]
[2018.02.09-17.32.43:147][383]LogWindows: Error: [Callstack] 0x00000000C69428D6 UE4Editor-Drone_follower.dll!ABall::Tick() [c:\users\4r35\documents\unreal projects\drone_follower\source\drone_follower\ball.cpp:44]
Yes, but I does not found any error in these functions…
actorscontroller.cpp
// Fill out your copyright notice in the Description page of Project Settings.
#include "ActorsController.h"
#include "Drone_follower.h"
#include "Messages.h"
#include "CustomData.h"
#include "EngineUtils.h"
// Sets default values
AActorsController::AActorsController()
{
// Set this actor to call Tick() every frame. You can turn this off to improve performance if you don't need it.
PrimaryActorTick.bCanEverTick = true;
//Istantiate Communication Component
OurCommunicationComponent = CreateDefaultSubobject<UUDP_Component>(TEXT("Communication Component"));
}
// Called when the game starts or when spawned
void AActorsController::BeginPlay()
{
Super::BeginPlay();
}
// Called every frame
void AActorsController::Tick(float DeltaTime)
{
Super::Tick(DeltaTime);
// Get Data
OurCommunicationComponent->GetData(&ReceivedData); //Store in a local variable the received data
//Serialize received data
/*for (i = 0; i < sizeof(struct FCustomPoseData); i++){
*((uint8*)(&VehiclePose) + i) = ReceivedData[i];
}*/
}
void AActorsController::ReturnNewData(FCustomPoseData *NewData) {
*NewData = ReceivedData;
}
void AActorsController::PreInitializeComponents() {
Super::PreInitializeComponents();
OurCommunicationComponent->StartUDPComm("PawnCommunicationComponent");
}Ball.cpp
// Fill out your copyright notice in the Description page of Project Settings.
#include "Ball.h"
#include "Messages.h"
#include "CustomData.h"
#include "ActorsController.h"
#include "Drone_follower.h"
// Sets default values
ABall::ABall()
{
// Set this actor to call Tick() every frame. You can turn this off to improve performance if you don't need it.
PrimaryActorTick.bCanEverTick = true;
SetActorLocation(FVector(0.0f, 0.0f, 29.0f));
//Instantiate static mesh component
BallVisibleComponent = CreateDefaultSubobject<UStaticMeshComponent>(TEXT("BallVisibleComponent"));
//Get actor controller pointer
//Get ActorsController pointer for receiving position
for (TObjectIterator<AActorsController> Itr; Itr; ++Itr) {
if (Itr->IsA(AActorsController::StaticClass())) {
ActorController = *Itr;
}
}
}
// Called when the game starts or when spawned
void ABall::BeginPlay()
{
Super::BeginPlay();
SetActorLocation(FVector(0.0f, 0.0f, 0.0f));
}
// Called every frame
void ABall::Tick(float DeltaTime)
{
FCustomPoseData NewData;
Super::Tick(DeltaTime);
ActorController->ReturnNewData(&NewData);
SetPose(&NewData);
}
void ABall::SetPose(FCustomPoseData* ReceivedData) {
FVector Position;
//Received measures are in cm --> convert into m
Position.X = 100 * ReceivedData->ball_X;
Position.Y = 100 * ReceivedData->ball_Y;
Position.Z = 100 * ReceivedData->ball_Z;
SetActorLocation(Position);
}Are you sure this is right?
void AActorsController::ReturnNewData(FCustomPoseData *NewData) {
*NewData = ReceivedData;
}Yes, I do not see any error, is declared here in the ActorsController.h file:
// Fill out your copyright notice in the Description page of Project Settings.
#pragma once
#include "CoreMinimal.h"
#include "GameFramework/Actor.h"
#include "UDP_Component.h"
#include "CustomData.h"
#include "ActorsController.generated.h"
UCLASS()
class DRONE_FOLLOWER_API AActorsController : public AActor
{
GENERATED_BODY()
public:
// Sets default values for this actor's properties
AActorsController();
// Called when the game starts or when spawned
virtual void BeginPlay() override;
virtual void Tick(float DeltaTime) override;
virtual void PreInitializeComponents() override;
void ReturnNewData(FCustomPoseData* NewData);
private:
UPROPERTY(EditAnywhere, Category = "Remote Address")
class UUDP_Component* OurCommunicationComponent;
FCustomPoseData ReceivedData;
};I believe the problem is in this assignment:
*NewData = ReceivedData;
How are you allocating memory to the pointer before the assignment?
The Ball class creates a local variable and then calls that method:
FCustomPoseData NewData;
Super::Tick(DeltaTime);
ActorController->ReturnNewData(&NewData);Hello,
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Thanks