Components

Komponenty v ECS architektuře Hytale.

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Co je Komponenta?

Komponenta je čistě datová struktura bez logiky. Obsahuje pouze data a gettery/settery.

// Komponenta = pouze data
public class HealthComponent implements Component {
    private int currentHealth;
    private int maxHealth;
    // Pouze gettery a settery
    public int getCurrentHealth() { return currentHealth; }
    public void setCurrentHealth(int health) { this.currentHealth = health; }
    public int getMaxHealth() { return maxHealth; }
    public void setMaxHealth(int max) { this.maxHealth = max; }
    @Override
    public Component clone() {
        HealthComponent copy = new HealthComponent();
        copy.currentHealth = this.currentHealth;
        copy.maxHealth = this.maxHealth;
        return copy;
    }
}

Logika patří do Systémů, ne do Komponent!

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Vestavěné Komponenty

Player Komponenty

| Komponenta | Popis |
|------------|-------|
| Player | Základní player data |
| PlayerRef | Reference na hráče (UUID, username) |
| TransformComponent | Pozice a rotace |
| HeadRotation | Rotace hlavy |

Entity Komponenty

| Komponenta | Popis |
|------------|-------|
| NetworkId | Síťové ID entity |
| BoundingBox | Kolizní box |
| ModelComponent | 3D model |
| Nameplate | Jmenovka nad entitou |

State Komponenty

| Komponenta | Popis |
|------------|-------|
| MovementStatesComponent | Stav pohybu |
| EffectControllerComponent | Aktivní efekty |
| KnockbackComponent | Knockback fyzika |

Speciální Komponenty

| Komponenta | Popis |
|------------|-------|
| Intangible | Entity nelze interagovat |
| HiddenFromAdventurePlayers | Skrytá v adventure módu |
| Container | Inventář/kontejner |

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Registrace Vlastní Komponenty

1. Definice Komponenty

public class CustomStatsComponent implements Component {
    private int kills;
    private int deaths;
    private long playTime;
    public CustomStatsComponent() {
        this.kills = 0;
        this.deaths = 0;
        this.playTime = 0;
    }
    // Gettery
    public int getKills() { return kills; }
    public int getDeaths() { return deaths; }
    public long getPlayTime() { return playTime; }
    // Settery
    public void setKills(int kills) { this.kills = kills; }
    public void setDeaths(int deaths) { this.deaths = deaths; }
    public void setPlayTime(long time) { this.playTime = time; }
    // Utility metody
    public void incrementKills() { this.kills++; }
    public void incrementDeaths() { this.deaths++; }
    public double getKDRatio() {
        return deaths == 0 ? kills : (double) kills / deaths;
    }
    // Povinná metoda clone()
    @Nonnull
    @Override
    public Component clone() {
        CustomStatsComponent copy = new CustomStatsComponent();
        copy.kills = this.kills;
        copy.deaths = this.deaths;
        copy.playTime = this.playTime;
        return copy;
    }
}

2. Registrace v Pluginu

public class MyPlugin extends JavaPlugin {
    private static MyPlugin instance;
    private ComponentType customStatsType;
    public MyPlugin(JavaPluginInit init) {
        super(init);
    }
    public static MyPlugin get() {
        return instance;
    }
    @Override
    protected void setup() {
        instance = this;
        // Registrace komponenty
        this.customStatsType = getEntityStoreRegistry().registerComponent(
            CustomStatsComponent.class,
            CustomStatsComponent::new  // Factory pro nové instance
        );
    }
    // Getter pro ComponentType
    public ComponentType getCustomStatsType() {
        return customStatsType;
    }
}

3. Použití Komponenty

// Získání ComponentType
ComponentType statsType =
    MyPlugin.get().getCustomStatsType();
// Čtení komponenty
CustomStatsComponent stats = store.getComponent(ref, statsType);
if (stats != null) {
    int kills = stats.getKills();
}
// Přidání komponenty k entitě
store.addComponent(ref, statsType, new CustomStatsComponent());
// Zajištění že komponenta existuje (vytvoří pokud neexistuje)
CustomStatsComponent stats = store.ensureAndGetComponent(ref, statsType);

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Přístup ke Komponentám

Základní Přístup

// Vždy kontroluj null!
Player player = store.getComponent(ref, Player.getComponentType());
if (player == null) {
    return; // Entita nemá Player komponentu
}
// Nyní bezpečné použití
String name = player.getName();

Kontrola Existence

// Metoda 1: Kontrola null
Player player = store.getComponent(ref, Player.getComponentType());
if (player != null) {
    // Použij player
}
// Metoda 2: hasComponent (méně efektivní - dvojí lookup)
if (store.hasComponent(ref, Player.getComponentType())) {
    Player player = store.getComponent(ref, Player.getComponentType());
}

Doporučeno: Použij metodu 1 - jednoduchý lookup a null kontrola.

Více Komponent Najednou

Player player = store.getComponent(ref, Player.getComponentType());
TransformComponent transform = store.getComponent(ref, TransformComponent.getComponentType());
CustomStatsComponent stats = store.getComponent(ref, MyPlugin.get().getCustomStatsType());
if (player != null && transform != null && stats != null) {
    // Všechny komponenty existují
    Vector3d position = transform.getPosition();
    int kills = stats.getKills();
}

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Store Operace

Čtení

// Získej komponentu
T component = store.getComponent(ref, componentType);
// Kontrola existence
boolean has = store.hasComponent(ref, componentType);

Zápis

// Přidej komponentu
store.addComponent(ref, componentType, component);
// Nastav/přepiš komponentu
store.setComponent(ref, componentType, component);
// Zajisti existenci a získej
T component = store.ensureAndGetComponent(ref, componentType);
// Odeber komponentu
store.removeComponent(ref, componentType);

V CommandBuffer (pro systémy)

@Override
public void handle(..., CommandBuffer commandBuffer, ...) {
    // Použij commandBuffer pro modifikace během iterace
    commandBuffer.addComponent(ref, componentType, newComponent);
    commandBuffer.removeComponent(ref, componentType);
}

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ComponentType

ComponentType je identifikátor typu komponenty.

Vestavěné Typy

// Získání přes statickou metodu
ComponentType playerType = Player.getComponentType();
ComponentType playerRefType = PlayerRef.getComponentType();
ComponentType transformType = TransformComponent.getComponentType();

Vlastní Typy

// Registrace vrací ComponentType
ComponentType myType =
    getEntityStoreRegistry().registerComponent(MyComponent.class, MyComponent::new);
// Uložení v pluginu pro pozdější použití
public ComponentType getMyComponentType() {
    return myType;
}

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Příklad: TeleportHistory (z TeleportPlugin)

public class TeleportHistory implements Component {
    private final List history = new ArrayList<>();
    public void append(World world, Vector3d position, Vector3f rotation, String description) {
        history.add(new TeleportEntry(world.getName(), position, rotation, description));
    }
    public TeleportEntry getLastEntry() {
        return history.isEmpty() ? null : history.get(history.size() - 1);
    }
    @Nonnull
    @Override
    public Component clone() {
        TeleportHistory copy = new TeleportHistory();
        copy.history.addAll(this.history);
        return copy;
    }
    public record TeleportEntry(String worldName, Vector3d position, Vector3f rotation, String description) {}
}
// Registrace
this.teleportHistoryComponentType = EntityStore.REGISTRY.registerComponent(
    TeleportHistory.class,
    TeleportHistory::new
);
// Použití
TeleportHistory history = store.ensureAndGetComponent(ref, TeleportHistory.getComponentType());
history.append(world, previousPos, previousRotation, "Teleport to spawn");

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Příklad: WarpComponent (z TeleportPlugin)

// Record komponenta - immutable
public static record WarpComponent(Warp warp) implements Component {
    public static ComponentType getComponentType() {
        return TeleportPlugin.get().warpComponentType;
    }
    @Nonnull
    @Override
    public Component clone() {
        return new WarpComponent(this.warp);
    }
}

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Shrnutí

| Operace | Metoda |
|---------|--------|
| Čtení | store.getComponent(ref, type) |
| Kontrola | store.hasComponent(ref, type) |
| Přidání | store.addComponent(ref, type, comp) |
| Nastavení | store.setComponent(ref, type, comp) |
| Zajištění | store.ensureAndGetComponent(ref, type) |
| Odebrání | store.removeComponent(ref, type) |
| Registrace | getEntityStoreRegistry().registerComponent(...) |