RelativeTeleportPacket.java

package com.galaxtone.reltp;

import java.util.UUID;

import io.netty.buffer.ByteBuf;
import net.minecraft.client.Minecraft;
import net.minecraft.entity.Entity;
import net.minecraft.entity.player.EntityPlayer;
import net.minecraft.entity.player.EntityPlayerMP;
import net.minecraft.util.math.Vec3d;
import net.minecraftforge.fml.common.network.simpleimpl.IMessage;
import net.minecraftforge.fml.common.network.simpleimpl.IMessageHandler;
import net.minecraftforge.fml.common.network.simpleimpl.MessageContext;

public class RelativeTeleportPacket implements IMessage {

	private boolean isPlayer;
	private int entityId;
	private UUID uuid;

	private Vec3d relativePosition;
	private Vec3d rotationOrigin;
	private float relativeYaw;
	private float relativePitch;

	@Override
	public String toString() {
		return "{" + (this.isPlayer ? "Player UUID: " + this.uuid : "Entity ID: " + this.entityId) + ", Position: " + relativePosition.toString() + ", Origin: " + rotationOrigin.toString() + ", Rotation: [" + relativeYaw + ", " + relativePitch + "]}";
	}

	public RelativeTeleportPacket(Entity entity, Vec3d relativePosition, Vec3d rotationOrigin, float relativeYaw, float relativePitch) {
		if (entity instanceof EntityPlayerMP) {
			this.isPlayer = true;
			
			EntityPlayerMP player = (EntityPlayerMP) entity;
			this.uuid = EntityPlayer.getUUID(player.getGameProfile());
		} else {
			this.isPlayer = false;
			this.entityId = entity.getEntityId();
		}
		
		this.relativePosition = relativePosition;
		this.rotationOrigin = rotationOrigin;
		this.relativeYaw = relativeYaw;
		this.relativePitch = relativePitch;
	}

	public RelativeTeleportPacket() {}

	@Override
	public void fromBytes(ByteBuf buffer) {
		this.isPlayer = buffer.readBoolean();
		if (this.isPlayer) {
			this.uuid = new UUID(buffer.readLong(), buffer.readLong());
		} else {
			this.entityId = buffer.readInt();
		}
		
		this.relativePosition = new Vec3d(buffer.readDouble(), buffer.readDouble(), buffer.readDouble());
		this.rotationOrigin = new Vec3d(buffer.readDouble(), buffer.readDouble(), buffer.readDouble());
		this.relativeYaw = buffer.readFloat();
		this.relativePitch = buffer.readFloat();
	}

	@Override
	public void toBytes(ByteBuf buffer) {
		buffer.writeBoolean(this.isPlayer);
		if (this.isPlayer) {
			buffer.writeLong(this.uuid.getMostSignificantBits());
			buffer.writeLong(this.uuid.getLeastSignificantBits());
		} else {
			buffer.writeInt(this.entityId);
		}
		
		buffer.writeDouble(relativePosition.x);
		buffer.writeDouble(relativePosition.y);
		buffer.writeDouble(relativePosition.z);
		
		buffer.writeDouble(rotationOrigin.x);
		buffer.writeDouble(rotationOrigin.y);
		buffer.writeDouble(rotationOrigin.z);

		buffer.writeFloat(relativeYaw);
		buffer.writeFloat(relativePitch);
	}

	public static final class Handler implements IMessageHandler<RelativeTeleportPacket, IMessage> {

		@Override
		public IMessage onMessage(RelativeTeleportPacket message, MessageContext context) {
			Minecraft minecraft = Minecraft.getMinecraft();

			Entity entity;
			if (message.isPlayer)
				entity = minecraft.world.getPlayerEntityByUUID(message.uuid);
			else
				entity = minecraft.world.getEntityByID(message.entityId);
			
			minecraft.addScheduledTask(() -> {
				TeleportUtils.relativeMove(entity, message.relativePosition, message.rotationOrigin, message.relativeYaw, message.relativePitch);
			});
			
			return null;
		}
	}
}