SetSimulatePhysics not working

Development World Creation
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1

Hi, I’m having an issue I wasn’t having earlier. I’ve created a class with a mesh, which has a box collider. The problem is, I can’t set simulate physics to true on my mesh component in BeginPlay(), or by calling a custom function. The only way I can set physics is in the constructor, but that fires a warning after exiting PIE mode. In my EnablePhysicsOnRoot function I used to debug a bit, the physics aren’t enabled, I am also not getting “MeshComponent NOT found”, but I AM getting “EnablePhysicsOnRoot Fired” Message, as well as “MeshComponent Found”. On an earlier project I was able to call this in BeginPlay with no issues. Any help is appreciated.

//PhysicsActorTest.h

#pragma once

#include "GameFramework/Actor.h"
#include "PhysicsActorTest.generated.h"

/**
 * 
 */
UCLASS()
class APhysicsActorTest : public AActor
{
	GENERATED_UCLASS_BODY()

	UPROPERTY()
	TSubobjectPtr<UStaticMeshComponent> MeshComp;

	UFUNCTION()
	void EnablePhysicsOnRoot();

	//Override Functions
	virtual void BeginPlay() OVERRIDE;
	virtual void Tick(float DeltaSeconds) OVERRIDE;
};

// PhysicsActorTest.cpp

#include "CompTest.h"
#include "PhysicsActorTest.h"


APhysicsActorTest::APhysicsActorTest(const class FPostConstructInitializeProperties& PCIP)
: Super(PCIP)
{
	static ConstructorHelpers::FObjectFinder<UStaticMesh>Mesh(TEXT("Static'/Game/Meshes/MyMesh.MyMesh'"));
	MeshComp = PCIP.CreateDefaultSubobject<UStaticMeshComponent>(this, (TEXT("Mesh")));
	MeshComp->StaticMesh = Mesh.Object;	
	RootComponent = MeshComp;
	PrimaryActorTick.bCanEverTick = true;
}

void APhysicsActorTest::BeginPlay()
{
	Super::BeginPlay();
	APhysicsActorTest::EnablePhysicsOnRoot();
}

void APhysicsActorTest::Tick(float DeltaSeconds)
{
	Super::Tick(DeltaSeconds);
}

void APhysicsActorTest::EnablePhysicsOnRoot()
{
	if (MeshComp)
	{
		MeshComp->SetSimulatePhysics(true);
		GEngine->AddOnScreenDebugMessage(-1, 5, FColor::Red, TEXT("MeshComponent found!"));
	}

	else
	{
		GEngine->AddOnScreenDebugMessage(-1, 5, FColor::Red, TEXT("MeshComponent not found!"));
	}

	GEngine->AddOnScreenDebugMessage(-1, 5, FColor::Red, TEXT("EnablePhysicsOnRoot Fired."));
}
2

Problem solved. SetSimulatePhysics was working after all. I needed to wake up the rigidbody using WakeRigidBody() :open_mouth:

if (MeshComp)
	{
		MeshComp->SetSimulatePhysics(true);
		MeshComp->WakeRigidBody();
		GEngine->AddOnScreenDebugMessage(-1, 5, FColor::Red, TEXT("MeshComponent found!"));
	}
3

Do you know how to constraint he physics to an axis?