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c++linetraceunreal-engine4raycasting

Unreal c++ Call a void from a Actor With LineTrace


Im new to c++ (use to c#) and trying to call a void on a Actor when it gets hit with a raycast and send it the cords. Heres the script header that im trying to call "EditMesh" on (near the bottom)

 #pragma once
    #include "CoreMinimal.h"
    #include "GameFramework/Actor.h"
    #include "ProceduralMeshComponent.h"
    //#include "Core.h"
    #include "Chunk.generated.h"




    UCLASS()
    class VOXELWARS_API AChunk : public AActor 
    {

        GENERATED_BODY()

    public:
        // Sets default values for this actor's properties
        AChunk();

    protected:
        // Called when the game starts or when spawned
        virtual void BeginPlay() override;


    public:
        // Called every frame
        //virtual void Tick(float DeltaTime) override;

        //UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = Default)
        //  UMaterialInterface* TheMaterial;
        UPROPERTY(EditAnywhere)
            AChunk* ChunkRef; 

        UPROPERTY(EditAnywhere)
            class UMaterialInterface* OnMaterial;

        UPROPERTY(VisibleAnywhere)
    UProceduralMeshComponent * mesh;
        UPROPERTY(VisibleAnywhere)
    int faceCount = 0;
    TArray<FVector> vertices;
    UPROPERTY(VisibleAnywhere)
    TArray<int32> Triangles;
    TArray<FVector> normals; 
    TArray<FVector2D> UV0;
    TArray<FProcMeshTangent> tangents;
    TArray<FLinearColor> vertexColors;
    TArray<FVector2D> blocks; 

    int worldData[16][16][16] = { {} };
    float tUnit = 0.0625; 


    public:void CubeTop(int x = 0, int y = 0, int z = 0, int block = 0);
    public:void CubeNorth(int x = 0, int y = 0, int z = 0, int block = 0);
    public:void CubeEast(int x = 0, int y = 0, int z = 0, int block = 0);
    public:void CubeSouth(int x = 0, int y = 0, int z = 0, int block = 0);
    public:void CubeWest(int x = 0, int y = 0, int z = 0, int block = 0);
    public:void CubeBot(int x = 0, int y = 0, int z = 0, int block = 0);
    public:void Cube(FVector2D texturePos);
    public:void UpdateMesh(); 
    public:void ClearMeshData(); 
    public:void GenMesh();
    public:void EditMesh(int x = 0, int y = 0, int z = 0, int block = 0); //here

    public:int Chk(int x = 0, int y = 0, int z = 0);
    //     int* mBlock(int x = 0, int y = 0, int z = 0);
    };

And here is part of the cpp of the other script that I want to call EditMesh() with

        #include "Chunk.h"
        #include "VoxelWarsCharacter.h"
        #include "VoxelWarsProjectile.h"
        #include "Animation/AnimInstance.h"
        #include "Camera/CameraComponent.h"
        #include "Components/CapsuleComponent.h"
        #include "Components/InputComponent.h"
        #include "GameFramework/InputSettings.h"
        #include "HeadMountedDisplayFunctionLibrary.h"
        #include "Kismet/GameplayStatics.h"
        #include "MotionControllerComponent.h"
        #include "XRMotionControllerBase.h" // for 

    void AVoxelWarsCharacter::OnFire()
    {
        FVector StartLocation = GetActorLocation(); //your location 
        StartLocation.Z += 15; 
        FVector EndLocation = StartLocation + (FirstPersonCameraComponent->GetForwardVector() * 4000.f); //get forward dir
        FHitResult Hit;
        FCollisionQueryParams ColParms; //ignor stuff
        ColParms.AddIgnoredActor(this);//ignor hitting self

        GetWorld()->LineTraceSingleByChannel(Hit, StartLocation, EndLocation, ECC_Visibility, ColParms);//ECC_WorldDynamic will only hit Actors, ECC_Visibility is everything

        if (Hit.GetActor()) {
            //Hit.GetActor()->AChunk::EditMesh(0, 0, 0, 1);
            GEngine->AddOnScreenDebugMessage(-1, 5.f, FColor(255,255,255), "Hit a actor");
            UKismetSystemLibrary::DrawDebugLine(GetWorld(), StartLocation, Hit.Location, FColor(255, 255, 0), 5, 1);//FColor::Red 

            Hit.GetActor()->FindComponentByClass<AChunk>()->EditMesh((int)Hit.Location.X, (int)Hit.Location.Y, (int)Hit.Location.Z, 0); 
           //How do I do this?????????
        }
    }

Errors I get

CompilerResultsLog: Error: D:\ProgramFiles\Epic Games\4.19\UE_4.19\Engine\Source\Runtime\Engine\Classes\GameFramework/Actor.h(2640) : error C2338: 'T' template parameter to FindComponentByClass must be derived from UActorComponent CompilerResultsLog:

Error: C:\Users\nolan\Desktop\VoxelWarsUR\Project\VoxelWars\Source\VoxelWars\VoxelWarsCharacter.cpp(160) : note: see reference to function template instantiation 'T *AActor::FindComponentByClass(void) const' being compiled


Solution

  • parameter to FindComponentByClass must be derived from UActorComponent

    Line 160 of VoxelWarsCharacter.cpp:

    FindComponentByClass<AChunk>
    

    AChunk isn't a component. Components start with U.