Hi all,
I’m currently facing a strange behavior when I call RemoveInstance from C++.
Basically I need to remove only one instanced static mesh at time, I managed to remove the correct one but for some reason the last instance mesh disappears but It’s collisions are still there (I can walk on hit but It’s not visible), then the more instances I remove the more this behavior gets worse, for example some meshes appears again and ohers are visible but without collision. I can post images or videos if needed;
Actually It’s really difficult to explain what happens ahaha.
So here’s the code called by the Player Tick function, it’s a basic linetrace:
FHitResult Hit;
FVector StartTrace = FirstPersonCameraComponent->GetComponentLocation();
FVector EndTrace = (FirstPersonCameraComponent->GetForwardVector() * Range) + StartTrace;
FCollisionQueryParams CollisionParams;
CollisionParams.AddIgnoredActor(this);
GetWorld()->LineTraceSingleByChannel(Hit, StartTrace, EndTrace, ECollisionChannel::ECC_WorldDynamic, CollisionParams);
ABlock* IsBlock = Cast<ABlock>(Hit.GetActor());
if (IsBlock == NULL)
{
CurrentBlock = nullptr;
return;
}
CurrentBlock = IsBlock;
CurrentBlockIndex = Hit.Item; // Maybe this cause all the problems?
Then when the player press the left mouse button this code is executed:
if (CurrentBlock != nullptr)
CurrentBlock->BreakBlock(CurrentBlockIndex);
ABlock.cpp
#include "Block.h"
// Sets default values
ABlock::ABlock()
{
// Set this actor to call Tick() every frame. You can turn this off to improve performance if you don't need it.
PrimaryActorTick.bCanEverTick = false;
ISM_Block = CreateDefaultSubobject<UInstancedStaticMeshComponent>(TEXT("Terrain"));
}
// Called when the game starts or when spawned
void ABlock::BeginPlay()
{
Super::BeginPlay();
/**
Here I simply place the cubes on the map, they are all 100x100
*/
for (int i = 0; i < 5; i++)
{
for (int j = 0; j < 5; j++)
{
FTransform transform(FRotator(0.0f, 0.0f, 0.0f), FVector(i*100.0f, j*100.0f, 0.0f), FVector(1.0f, 1.0f, 1.0f));
SM_Block->AddInstance(transform);
}
}
}
void ABlock::BreakBlock(int32& index)
{
ISM_Block->RemoveInstance(index);
}
I tried to implement an array of integers that holds a reference of the instances spawned by following this image that i found on the Live Training of the Instanced Static Meshes by Epic and then removing elements from that array whenever i call RemoveInstance but unfortunately nothing changed
I hope I was clear enough, and sorry for any misspelling.
Thanks in advance 
