Game mechanics in Unreal Engine involve various systems and components that define how a game operates and responds to player input. Here’s an overview of some key game mechanics and how to implement them in Unreal Engine:
1. Character Movement
Basic Movement:
Use the Character class, which comes with built-in movement capabilities.
Set up input bindings in the project’s settings to map player inputs to character movements.
// In Character class (e.g., MyCharacter.cpp)
void AMyCharacter::SetupPlayerInputComponent(UInputComponent* PlayerInputComponent)
{
Super::SetupPlayerInputComponent(PlayerInputComponent);
// Bind movement functions
PlayerInputComponent->BindAxis(“MoveForward”, this, &AMyCharacter::MoveForward);
PlayerInputComponent->BindAxis(“MoveRight”, this, &AMyCharacter::MoveRight);
}
void AMyCharacter::MoveForward(float Value)
{
AddMovementInput(GetActorForwardVector() * Value);
}
void AMyCharacter::MoveRight(float Value)
{
AddMovementInput(GetActorRightVector() * Value);
}
2. Health System
Basic Health System:
Create variables for health and implement damage and healing functions.
// In Character class (e.g., MyCharacter.h)
public:
float Health;
float MaxHealth;
void TakeDamage(float DamageAmount);
void Heal(float HealAmount);
// In Character class (e.g., MyCharacter.cpp)
AMyCharacter::AMyCharacter()
{
Health = 100.0f;
MaxHealth = 100.0f;
}
void AMyCharacter::TakeDamage(float DamageAmount)
{
Health -= DamageAmount;
if (Health <= 0.0f)
{
Health = 0.0f;
// Handle character death
}
}
void AMyCharacter::Heal(float HealAmount)
{
Health += HealAmount;
if (Health > MaxHealth)
{
Health = MaxHealth;
}
}
3. Inventory System
Basic Inventory System:
Use an array or a list to store inventory items.
// In Character class (e.g., MyCharacter.h)
public:
TArray<FString> Inventory;
void AddItemToInventory(FString ItemName);
void RemoveItemFromInventory(FString ItemName);
// In Character class (e.g., MyCharacter.cpp)
void AMyCharacter::AddItemToInventory(FString ItemName)
{
Inventory.Add(ItemName);
}
void AMyCharacter::RemoveItemFromInventory(FString ItemName)
{
Inventory.Remove(ItemName);
}
4. Combat System
Basic Combat System:
Implement functions for attacking and handling enemy interaction.
// In Character class (e.g., MyCharacter.h)
public:
float AttackDamage;
void Attack();
// In Character class (e.g., MyCharacter.cpp)
AMyCharacter::AMyCharacter()
{
AttackDamage = 20.0f;
}
void AMyCharacter::Attack()
{
// Perform a line trace or overlap to detect enemies
FHitResult HitResult;
FVector Start = GetActorLocation();
FVector End = Start + (GetActorForwardVector() * 100.0f);
FCollisionQueryParams CollisionParams;
CollisionParams.AddIgnoredActor(this);
if (GetWorld()->LineTraceSingleByChannel(HitResult, Start, End, ECC_Visibility, CollisionParams))
{
AActor* HitActor = HitResult.GetActor();
if (HitActor)
{
// Apply damage to the hit actor
UGameplayStatics::ApplyDamage(HitActor, AttackDamage, GetController(), this, UDamageType::StaticClass());
}
}
}
5. Save/Load System
Basic Save/Load System:
Use Unreal Engine’s SaveGame class to implement save and load functionality.
// In custom SaveGame class (e.g., MySaveGame.h)
UCLASS()
class MYGAME_API UMySaveGame : public USaveGame
{
GENERATED_BODY()
public:
UPROPERTY(VisibleAnywhere, Category = Basic)
float PlayerHealth;
UPROPERTY(VisibleAnywhere, Category = Basic)
FVector PlayerLocation;
};
// In Character class (e.g., MyCharacter.cpp)
void AMyCharacter::SaveGame()
{
UMySaveGame* SaveGameInstance = Cast<UMySaveGame>(UGameplayStatics::CreateSaveGameObject(UMySaveGame::StaticClass()));
SaveGameInstance->PlayerHealth = Health;
SaveGameInstance->PlayerLocation = GetActorLocation();
UGameplayStatics::SaveGameToSlot(SaveGameInstance, “PlayerSaveSlot”, 0);
}
void AMyCharacter::LoadGame()
{
UMySaveGame* LoadGameInstance = Cast<UMySaveGame>(UGameplayStatics::LoadGameFromSlot(“PlayerSaveSlot”, 0));
if (LoadGameInstance)
{
Health = LoadGameInstance->PlayerHealth;
SetActorLocation(LoadGameInstance->PlayerLocation);
}
}
Additional Resources
Unreal Engine Documentation: Detailed guides and references for various Unreal Engine systems and features.
Unreal Engine Forums and Community: Engage with other developers, ask questions, and share knowledge.
Unreal Engine Marketplace: Find assets, plugins, and tools to enhance your projects.
Here you can read my Journal
Notion : https://www.notion.so/Unreal-engine-game-dev-61550dd61f0d41948863ac7e802296f8?pvs=4
