package com.dronemod.entity; import com.dronemod.ModEntities; import com.dronemod.ModSounds; import com.dronemod.item.ControlTabletItem; import com.dronemod.network.DroneSyncPayload; import com.dronemod.network.DroneOpenScreenPayload; import net.fabricmc.fabric.api.networking.v1.ServerPlayNetworking; import net.minecraft.component.DataComponentTypes; import net.minecraft.component.type.NbtComponent; import net.minecraft.entity.Entity; import net.minecraft.entity.EntityType; import net.minecraft.entity.MovementType; import net.minecraft.entity.data.DataTracker; import net.minecraft.entity.data.TrackedData; import net.minecraft.entity.data.TrackedDataHandlerRegistry; import net.minecraft.entity.player.PlayerEntity; import net.minecraft.inventory.SimpleInventory; import net.minecraft.item.ItemStack; import net.minecraft.nbt.NbtCompound; import net.minecraft.nbt.NbtElement; import net.minecraft.nbt.NbtList; import net.minecraft.registry.RegistryWrapper; import net.minecraft.server.network.ServerPlayerEntity; import net.minecraft.server.world.ServerWorld; import net.minecraft.sound.SoundCategory; import net.minecraft.text.Text; import net.minecraft.util.ActionResult; import net.minecraft.util.Hand; import net.minecraft.util.collection.DefaultedList; import net.minecraft.util.math.MathHelper; import net.minecraft.util.math.Vec3d; import net.minecraft.world.World; import java.util.UUID; public class DroneEntity extends Entity { private static final TrackedData FLYING = DataTracker.registerData(DroneEntity.class, TrackedDataHandlerRegistry.BOOLEAN); private static final TrackedData ROTOR_ANGLE = DataTracker.registerData(DroneEntity.class, TrackedDataHandlerRegistry.FLOAT); private UUID ownerUuid; private final SimpleInventory inventory = new SimpleInventory(9); private boolean receivedInputThisTick = false; private int inputFlags = 0; private int noControlTicks = 0; private int syncCounter = 0; public DroneEntity(EntityType type, World world) { super(type, world); this.setNoGravity(true); } @Override protected void initDataTracker(DataTracker.Builder builder) { builder.add(FLYING, false); builder.add(ROTOR_ANGLE, 0f); } // ─── Server tick ────────────────────────────────────────────────────────── @Override public void tick() { super.tick(); if (!getWorld().isClient()) { serverTick(); } else { clientTick(); } } private void serverTick() { PlayerEntity owner = getOwner(); boolean ownerInRange = owner != null && distanceTo(owner) <= 64.0; boolean controlled = receivedInputThisTick && ownerInRange; if (controlled) { noControlTicks = 0; } else { noControlTicks++; } receivedInputThisTick = false; Vec3d vel = getVelocity(); if (controlled) { vel = computeControlledVelocity(vel, owner); dataTracker.set(FLYING, true); } else { vel = computeUncontrolledVelocity(vel); } // Ground collision stop if (isOnGround()) { if (vel.y < -0.45) { crash(); return; } vel = new Vec3d(vel.x * 0.4, Math.max(0, vel.y), vel.z * 0.4); if (vel.horizontalLengthSquared() < 0.0004) { vel = new Vec3d(0, 0, 0); dataTracker.set(FLYING, false); } } setVelocity(vel); move(MovementType.SELF, vel); // Spin rotors when moving boolean shouldSpin = dataTracker.get(FLYING) || vel.lengthSquared() > 0.0004; if (shouldSpin) { float next = (dataTracker.get(ROTOR_ANGLE) + 28f) % 360f; dataTracker.set(ROTOR_ANGLE, next); } inputFlags = 0; // Periodic sync to owner syncCounter++; if (syncCounter >= 4) { syncCounter = 0; if (owner instanceof ServerPlayerEntity sp && ownerInRange) { ServerPlayNetworking.send(sp, new DroneSyncPayload( getUuid(), getX(), getY(), getZ(), distanceTo(owner))); } } } private Vec3d computeControlledVelocity(Vec3d current, PlayerEntity owner) { float yaw = owner.getYaw(); double fwd = 0, str = 0, up = 0; if ((inputFlags & 0x01) != 0) fwd -= 1; if ((inputFlags & 0x02) != 0) fwd += 1; if ((inputFlags & 0x04) != 0) str -= 1; if ((inputFlags & 0x08) != 0) str += 1; if ((inputFlags & 0x10) != 0) up += 1; if ((inputFlags & 0x20) != 0) up -= 1; double rad = Math.toRadians(yaw); double dx = fwd * -MathHelper.sin((float) rad) + str * MathHelper.cos((float) rad); double dz = fwd * MathHelper.cos((float) rad) + str * MathHelper.sin((float) rad); Vec3d target = new Vec3d(dx * 0.45, up * 0.30, dz * 0.45); return current.multiply(0.72).add(target.multiply(0.28)); } private Vec3d computeUncontrolledVelocity(Vec3d current) { // Horizontal deceleration double nx = current.x * 0.82; double nz = current.z * 0.82; // Vertical: gentle descent while recently controlled, faster after prolonged loss double descentRate = noControlTicks > 60 ? -0.07 : -0.018; double ny = Math.max(current.y + descentRate, -0.45); return new Vec3d(nx, ny, nz); } private void crash() { World world = getWorld(); world.playSound(null, getX(), getY(), getZ(), ModSounds.DRONE_CRASH, SoundCategory.NEUTRAL, 1.0f, 0.85f + random.nextFloat() * 0.3f); for (int i = 0; i < inventory.size(); i++) { ItemStack stack = inventory.getStack(i); if (!stack.isEmpty()) dropStack(stack); } discard(); } private void clientTick() { // Smoothly animate rotor on client via tracked data — nothing extra needed. } // ─── Input from network ─────────────────────────────────────────────────── public void applyInput(int flags) { this.receivedInputThisTick = true; this.inputFlags = flags; } // ─── Entity interaction ─────────────────────────────────────────────────── @Override public ActionResult interact(PlayerEntity player, Hand hand) { ItemStack stack = player.getStackInHand(hand); if (stack.getItem() instanceof ControlTabletItem) { if (!getWorld().isClient()) { // Link tablet to this drone and open control screen ControlTabletItem.setLinkedDroneId(stack, getUuid()); setOwnerUuid(player.getUuid()); ServerPlayNetworking.send((ServerPlayerEntity) player, new DroneOpenScreenPayload(getUuid())); player.sendMessage(Text.translatable("item.dronemod.control_tablet.linked"), true); } return ActionResult.SUCCESS; } // Empty hand = pick up drone if (stack.isEmpty()) { if (!getWorld().isClient()) { dropStack(new ItemStack(ModEntities.DRONE.create(getWorld()) != null ? net.minecraft.item.Items.AIR : net.minecraft.item.Items.AIR)); // Drop the drone as an item ItemStack droneStack = new ItemStack(com.dronemod.ModItems.DRONE); dropStack(droneStack); for (int i = 0; i < inventory.size(); i++) { ItemStack s = inventory.getStack(i); if (!s.isEmpty()) dropStack(s); } discard(); } return ActionResult.SUCCESS; } return ActionResult.PASS; } // ─── Owner ──────────────────────────────────────────────────────────────── public void setOwnerUuid(UUID uuid) { this.ownerUuid = uuid; } public UUID getOwnerUuid() { return ownerUuid; } public PlayerEntity getOwner() { if (ownerUuid == null) return null; if (getWorld() instanceof ServerWorld sw) { return sw.getPlayerByUuid(ownerUuid); } return null; } // ─── Inventory ──────────────────────────────────────────────────────────── public SimpleInventory getDroneInventory() { return inventory; } // ─── Client accessor ────────────────────────────────────────────────────── public float getRotorAngle() { return dataTracker.get(ROTOR_ANGLE); } public boolean isFlying() { return dataTracker.get(FLYING); } // ─── NBT ────────────────────────────────────────────────────────────────── @Override protected void writeCustomDataToNbt(NbtCompound nbt, RegistryWrapper.WrapperLookup registries) { if (ownerUuid != null) nbt.putUuid("OwnerUuid", ownerUuid); DefaultedList items = DefaultedList.ofSize(inventory.size(), ItemStack.EMPTY); for (int i = 0; i < inventory.size(); i++) items.set(i, inventory.getStack(i)); net.minecraft.util.Inventories.writeNbt(nbt, items, registries); } @Override protected void readCustomDataFromNbt(NbtCompound nbt, RegistryWrapper.WrapperLookup registries) { if (nbt.containsUuid("OwnerUuid")) ownerUuid = nbt.getUuid("OwnerUuid"); DefaultedList items = DefaultedList.ofSize(9, ItemStack.EMPTY); net.minecraft.util.Inventories.readNbt(nbt, items, registries); for (int i = 0; i < items.size(); i++) inventory.setStack(i, items.get(i)); } @Override public boolean isCollidable() { return true; } }