Add entity metadata packet and object entity spawning

.idea/misc.xml

@@ -1,5 +1,10 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
+  <component name="EntryPointsManager">
+    <list size="1">
+      <item index="0" class="java.lang.String" itemvalue="com.squareup.moshi.FromJson" />
+    </list>
+  </component>
   <component name="ExternalStorageConfigurationManager" enabled="true" />
   <component name="ProjectRootManager" version="2" languageLevel="JDK_14" default="true" project-jdk-name="14" project-jdk-type="JavaSDK" />
   <component name="SuppressKotlinCodeStyleNotification">

test-plugin/src/main/kotlin/space/uranos/testplugin/TestPlugin.kt

@@ -3,12 +3,14 @@ package space.uranos.testplugin
 import space.uranos.Uranos
 import space.uranos.chat.ChatColor
 import space.uranos.chat.TextComponent
-import space.uranos.entity.MinecartEntity
 import space.uranos.entity.Position
+import space.uranos.entity.RideableMinecartEntity
 import space.uranos.net.ServerListInfo
 import space.uranos.net.event.ServerListInfoRequestEvent
 import space.uranos.net.event.SessionAfterLoginEvent
+import space.uranos.net.packet.play.EntityMetadataPacket
 import space.uranos.player.GameMode
+import space.uranos.player.event.PlayerReadyEvent
 import space.uranos.plugin.Plugin
 import space.uranos.testplugin.anvil.AnvilWorld
 import space.uranos.util.RGBColor
@@ -104,10 +106,22 @@ class TestPlugin : Plugin("Test", "1.0.0") {
             }
         }
 
-        // Not showing up yet because no metadata is sent
+        val entity = Uranos.create<RideableMinecartEntity>()
-        val entity = Uranos.create<MinecartEntity>()
         entity.position = Position(0.0, 4.0, 0.0)
-//        entity.setWorld(world)
+        entity.setWorld(world)
+
+        Uranos.eventBus.on<PlayerReadyEvent> {
+            it.player.session.send(EntityMetadataPacket(entity.numericID, listOf(
+                EntityMetadataPacket.MetadataEntry.Byte(0u, 0x00),
+                EntityMetadataPacket.MetadataEntry.Int(1u, 0x00),
+                EntityMetadataPacket.MetadataEntry.OptChat(2u, null),
+                EntityMetadataPacket.MetadataEntry.Boolean(3u, false),
+                EntityMetadataPacket.MetadataEntry.Boolean(4u, false),
+                EntityMetadataPacket.MetadataEntry.Boolean(5u, false),
+                EntityMetadataPacket.MetadataEntry.Int(6u, 0),
+                EntityMetadataPacket.MetadataEntry.Boolean(12u, true)
+            )))
+        }
 
         var x = 0f
         var y = -90f

uranos-api/src/main/kotlin/space/uranos/entity/Entity.kt

@@ -25,7 +25,7 @@ interface Entity {
     val numericID: Int
 
     /**
-     * Players that can see this entity.
+     * Players that can see this entity if it is in their view distance.
      */
     val viewers: MutableSet<Player>
 
@@ -38,6 +38,17 @@ interface Entity {
      * If players should be added to [viewers] when they enter [world].
      */
     var visibleToNewPlayers: Boolean
+
+    var glowing: Boolean // even experience orbs can glow
+
+    var invisible: Boolean
+
+    /**
+     * Whether this entity does not produce any sounds.
+     */
+    var silent: Boolean
+
+    var ignoreGravity: Boolean
 }
 
 /**

uranos-api/src/main/kotlin/space/uranos/entity/MinecartEntity.kt

@@ -0,0 +1,27 @@
+package space.uranos.entity
+
+import space.uranos.world.block.Block
+
+interface MinecartEntity: ObjectEntity, YawRotatable, PitchRotatable {
+    /**
+     * Default is `0`.
+     */
+    val shakingPower: Int
+
+    /**
+     * Default is `1`.
+     */
+    val shakingDirection: Int
+
+    /**
+     * Default is `0.0`.
+     */
+    val shakingMultiplier: Float
+
+    val customBlock: Block?
+
+    /**
+     * The Y offset of the block inside the minecart, measured in 16ths of a block.
+     */
+    val blockOffset: Int
+}

uranos-api/src/main/kotlin/space/uranos/entity/RideableMinecartEntity.kt

@@ -0,0 +1,5 @@
+package space.uranos.entity
+
+interface RideableMinecartEntity : MinecartEntity {
+  companion object Type : MinecartEntityType()
+}

uranos-packet-codecs/src/main/kotlin/space/uranos/net/packet/play/EntityMetadataPacketCodec.kt

@@ -0,0 +1,34 @@
+package space.uranos.net.packet.play
+
+import io.netty.buffer.ByteBuf
+import space.uranos.net.MinecraftProtocolDataTypes.writeString
+import space.uranos.net.MinecraftProtocolDataTypes.writeVarInt
+import space.uranos.net.packet.OutgoingPacketCodec
+
+object EntityMetadataPacketCodec : OutgoingPacketCodec<EntityMetadataPacket>(0x44, EntityMetadataPacket::class) {
+    override fun EntityMetadataPacket.encode(dst: ByteBuf) {
+        dst.writeVarInt(entityID)
+
+        for (entry in metadata) {
+            dst.writeByte(entry.index.toInt())
+            dst.writeVarInt(entry.typeID)
+
+            when(entry) {
+                is EntityMetadataPacket.MetadataEntry.Byte -> dst.writeByte(entry.value.toInt())
+                is EntityMetadataPacket.MetadataEntry.Int -> dst.writeVarInt(entry.value)
+                is EntityMetadataPacket.MetadataEntry.Float -> dst.writeFloat(entry.value)
+                is EntityMetadataPacket.MetadataEntry.String -> dst.writeString(entry.value)
+                is EntityMetadataPacket.MetadataEntry.OptChat -> {
+                    if (entry.value == null) dst.writeBoolean(false)
+                    else {
+                        dst.writeBoolean(true)
+                        dst.writeString(entry.value!!.toJson())
+                    }
+                }
+                is EntityMetadataPacket.MetadataEntry.Boolean -> dst.writeBoolean(entry.value)
+            }
+        }
+
+        dst.writeByte(0xff)
+    }
+}

uranos-packet-codecs/src/main/kotlin/space/uranos/net/packet/play/EntityVelocityPacketCodec.kt

@@ -0,0 +1,14 @@
+package space.uranos.net.packet.play
+
+import io.netty.buffer.ByteBuf
+import space.uranos.net.MinecraftProtocolDataTypes.writeVarInt
+import space.uranos.net.packet.OutgoingPacketCodec
+
+object EntityVelocityPacketCodec : OutgoingPacketCodec<EntityVelocityPacket>(0x46, EntityVelocityPacket::class) {
+    override fun EntityVelocityPacket.encode(dst: ByteBuf) {
+        dst.writeVarInt(entityID)
+        dst.writeShort(x.toInt())
+        dst.writeShort(y.toInt())
+        dst.writeShort(z.toInt())
+    }
+}

uranos-packet-codecs/src/main/kotlin/space/uranos/net/packet/play/PlayProtocol.kt

@@ -14,10 +14,12 @@ object PlayProtocol : Protocol(
     DestroyEntitiesPacketCodec,
     DisconnectPacketCodec,
     EntityHeadYawPacketCodec,
+    EntityMetadataPacketCodec,
     EntityOrientationPacketCodec,
     EntityRelativeMovePacketCodec,
     EntityRelativeMoveWithOrientationPacketCodec,
     EntityTeleportPacketCodec,
+    EntityVelocityPacketCodec,
     IncomingKeepAlivePacketCodec,
     IncomingPlayerPositionPacketCodec,
     IncomingPluginMessagePacketCodec,

uranos-packet-codecs/src/main/kotlin/space/uranos/net/packet/play/PlayerOrientationPacketCodec.kt

@@ -7,7 +7,7 @@ import space.uranos.util.numbers.floorMod
 object PlayerOrientationPacketCodec :
     IncomingPacketCodec<PlayerOrientationPacket>(0x14, PlayerOrientationPacket::class) {
     override fun decode(msg: ByteBuf): PlayerOrientationPacket = PlayerOrientationPacket(
-        floorMod(msg.readFloat(), 360f),
+        floorMod(msg.readFloat(), 360f), // TODO: Ensure it is never 360 (should be 0 then)
         msg.readFloat(),
         msg.readBoolean()
     )

uranos-packet-codecs/src/main/kotlin/space/uranos/net/packet/play/SpawnLivingEntityPacketCodec.kt

@@ -20,8 +20,8 @@ object SpawnLivingEntityPacketCodec : OutgoingPacketCodec<SpawnLivingEntityPacke
         // This is named "head pitch" on wiki.vg, but it is actually head yaw.
         dst.writeByte(headYaw.mapToUByte(360f).toInt())
 
-        dst.writeShort((velocity.x * 8000).toInt().toShort().toInt())
+        dst.writeShort(velocityX.toInt())
-        dst.writeShort((velocity.y * 8000).toInt().toShort().toInt())
+        dst.writeShort(velocityY.toInt())
-        dst.writeShort((velocity.z * 8000).toInt().toShort().toInt())
+        dst.writeShort(velocityZ.toInt())
     }
 }

uranos-packet-codecs/src/main/kotlin/space/uranos/net/packet/play/SpawnObjectEntityPacketCodec.kt

@@ -16,8 +16,8 @@ object SpawnObjectEntityPacketCodec : OutgoingPacketCodec<SpawnObjectEntityPacke
         dst.writeByte(pitch.toInt())
         dst.writeByte(yaw.toInt())
         dst.writeInt(data)
-        dst.writeShort((velocity.x * 8000).toInt().toShort().toInt())
+        dst.writeShort(velocityX.toInt())
-        dst.writeShort((velocity.y * 8000).toInt().toShort().toInt())
+        dst.writeShort(velocityY.toInt())
-        dst.writeShort((velocity.z * 8000).toInt().toShort().toInt())
+        dst.writeShort(velocityZ.toInt())
     }
 }

uranos-packets/src/main/kotlin/space/uranos/net/packet/play/EntityMetadataPacket.kt

@@ -0,0 +1,21 @@
+package space.uranos.net.packet.play
+
+import space.uranos.chat.ChatComponent
+import space.uranos.net.packet.OutgoingPacket
+
+data class EntityMetadataPacket(
+    val entityID: Int,
+    val metadata: Iterable<MetadataEntry<*>>
+) : OutgoingPacket() {
+    sealed class MetadataEntry<T>(val typeID: kotlin.Int) {
+        abstract val index: UByte
+        abstract val value: T
+
+        data class Byte(override val index: UByte, override val value: kotlin.Byte) : MetadataEntry<kotlin.Byte>(0)
+        data class Int(override val index: UByte, override val value: kotlin.Int) : MetadataEntry<kotlin.Int>(1)
+        data class Float(override val index: UByte, override val value: kotlin.Float) : MetadataEntry<kotlin.Float>(2)
+        data class String(override val index: UByte, override val value: kotlin.String) : MetadataEntry<kotlin.String>(3)
+        data class OptChat(override val index: UByte, override val value: ChatComponent?) : MetadataEntry<ChatComponent?>(5)
+        data class Boolean(override val index: UByte, override val value: kotlin.Boolean) : MetadataEntry<kotlin.Boolean>(7)
+    }
+}

uranos-packets/src/main/kotlin/space/uranos/net/packet/play/EntityVelocityPacket.kt

@@ -0,0 +1,10 @@
+package space.uranos.net.packet.play
+
+import space.uranos.net.packet.OutgoingPacket
+
+data class EntityVelocityPacket(
+    val entityID: Int,
+    val x: Short,
+    val y: Short,
+    val z: Short
+) : OutgoingPacket()

uranos-packets/src/main/kotlin/space/uranos/net/packet/play/SpawnLivingEntityPacket.kt

@@ -1,6 +1,5 @@
 package space.uranos.net.packet.play
 
-import space.uranos.Vector
 import space.uranos.entity.EntityType
 import space.uranos.entity.Position
 import space.uranos.net.packet.OutgoingPacket
@@ -8,6 +7,8 @@ import java.util.UUID
 
 /**
  * Sent to spawn **living** entities.
+ *
+ * Velocity is measured in 1/8000 blocks per tick.
  */
 data class SpawnLivingEntityPacket(
     val entityID: Int,
@@ -17,8 +18,7 @@ data class SpawnLivingEntityPacket(
     val yaw: Float,
     val pitch: Float,
     val headYaw: Float,
-    /**
+    val velocityX: Short,
-     * Velocity in blocks per tick
+    val velocityY: Short,
-     */
+    val velocityZ: Short
-    val velocity: Vector
 ) : OutgoingPacket()

uranos-packets/src/main/kotlin/space/uranos/net/packet/play/SpawnObjectEntityPacket.kt

@@ -1,11 +1,12 @@
 package space.uranos.net.packet.play
 
-import space.uranos.Vector
 import space.uranos.net.packet.OutgoingPacket
 import java.util.UUID
 
 /**
  * Sent to spawn object entities.
+ *
+ * Velocity is measured in 1/8000 blocks per tick.
  */
 data class SpawnObjectEntityPacket(
     val entityID: Int,
@@ -17,5 +18,7 @@ data class SpawnObjectEntityPacket(
     val yaw: UByte,
     val pitch: UByte,
     val data: Int,
-    val velocity: Vector
+    val velocityX: Short,
+    val velocityY: Short,
+    val velocityZ: Short
 ) : OutgoingPacket()

uranos-packets/src/main/kotlin/space/uranos/util/SpawnEntity.kt

@@ -8,37 +8,45 @@ import space.uranos.net.packet.play.SpawnPaintingPacket
 import space.uranos.util.numbers.mapToUByte
 
 fun Entity.createSpawnPacket(): OutgoingPacket = when (this) {
-    is LivingEntity -> if (this is HasMovableHead) SpawnLivingEntityPacket(
+    is LivingEntity -> {
-        numericID,
+        val (velX, velY, velZ) = velocity.getAsVelocityPacketValues()
-        uuid,
+
-        type,
+        if (this is HasMovableHead) SpawnLivingEntityPacket(
-        position,
+            numericID,
-        headYaw,
+            uuid,
-        headPitch,
+            type,
-        headYaw,
+            position,
-        velocity
+            headYaw,
-    ) else SpawnLivingEntityPacket(
+            headPitch,
-        numericID,
+            headYaw,
-        uuid,
+            velX, velY, velZ
-        type,
+        ) else SpawnLivingEntityPacket(
-        position,
+            numericID,
-        if (this is YawRotatable) yaw else 0f,
+            uuid,
-        if (this is PitchRotatable) pitch else 0f,
+            type,
-        0f,
+            position,
-        velocity
+            if (this is YawRotatable) yaw else 0f,
-    )
+            if (this is PitchRotatable) pitch else 0f,
-    is ObjectEntity -> SpawnObjectEntityPacket(
+            0f,
-        numericID,
+            velX, velY, velZ
-        uuid,
+        )
-        type.numericID,
+    }
-        position.x,
+    is ObjectEntity -> {
-        position.y,
+        val (velX, velY, velZ) = velocity.getAsVelocityPacketValues()
-        position.z,
+
-        if (this is YawRotatable) yaw.mapToUByte(360f) else 0u,
+        SpawnObjectEntityPacket(
-        if (this is PitchRotatable) pitch.mapToUByte(360f) else 0u,
+            numericID,
-        getDataValue(),
+            uuid,
-        velocity
+            type.numericID,
-    )
+            position.x,
+            position.y,
+            position.z,
+            if (this is YawRotatable) yaw.mapToUByte(360f) else 0u,
+            if (this is PitchRotatable) pitch.mapToUByte(360f) else 0u,
+            getDataValue(),
+            velX, velY, velZ
+        )
+    }
     is PaintingEntity -> SpawnPaintingPacket(
         numericID,
         uuid,
@@ -51,7 +59,7 @@ fun Entity.createSpawnPacket(): OutgoingPacket = when (this) {
 
 fun ObjectEntity.getDataValue(): Int = when (this) {
     is ItemEntity -> 1
-    is MinecartEntity -> 2
+    is RideableMinecartEntity -> 0
     // TODO: Add remaining
     else -> throw IllegalArgumentException("Unknown entity type")
 }

uranos-packets/src/main/kotlin/space/uranos/util/Vector.kt

@@ -0,0 +1,9 @@
+package space.uranos.util
+
+import space.uranos.Vector
+
+fun Vector.getAsVelocityPacketValues() = Triple(
+    (x * 8000).toInt().toShort(),
+    (y * 8000).toInt().toShort(),
+    (z * 8000).toInt().toShort()
+)

uranos-server/src/main/kotlin/space/uranos/CreateEntityInstance.kt

@@ -0,0 +1,16 @@
+package space.uranos
+
+import space.uranos.entity.*
+import space.uranos.entity.impl.UranosBatEntity
+import space.uranos.entity.impl.UranosCowEntity
+import space.uranos.entity.impl.UranosCreeperEntity
+import space.uranos.entity.impl.UranosRideableMinecartEntity
+
+@Suppress("UNCHECKED_CAST")
+fun <T : Entity> createEntityInstance(server: UranosServer, type: EntityType<T>): T = when (type) {
+    CowEntity -> UranosCowEntity(server)
+    BatEntity -> UranosBatEntity(server)
+    CreeperEntity -> UranosCreeperEntity(server)
+    RideableMinecartEntity -> UranosRideableMinecartEntity(server)
+    else -> throw IllegalArgumentException("Entities of this type cannot be created with this function")
+} as T

uranos-server/src/main/kotlin/space/uranos/UranosServer.kt

@@ -5,8 +5,10 @@ import com.sksamuel.hoplite.ConfigLoader
 import com.sksamuel.hoplite.ConfigSource
 import kotlinx.coroutines.runBlocking
 import space.uranos.config.UranosConfig
-import space.uranos.entity.*
+import space.uranos.entity.Entity
-import space.uranos.entity.impl.*
+import space.uranos.entity.EntityType
+import space.uranos.entity.UranosEntity
+import space.uranos.entity.impl.UranosPlayerEntity
 import space.uranos.event.UranosEventBus
 import space.uranos.event.UranosEventHandlerPositionManager
 import space.uranos.logging.Logger
@@ -79,20 +81,8 @@ class UranosServer internal constructor() : Server() {
     private val internalEntities = HashSet<UranosEntity>()
     override val entities: Set<Entity> = internalEntities
 
-    override fun <T : Entity> create(type: EntityType<T>): T {
+    override fun <T : Entity> create(type: EntityType<T>): T =
-        val entity: UranosEntity = when (type) {
+        createEntityInstance(this, type).also { internalEntities.add(it as UranosEntity) }
-            CowEntity -> UranosCowEntity(this)
-            BatEntity -> UranosBatEntity(this)
-            CreeperEntity -> UranosCreeperEntity(this)
-            MinecartEntity -> UranosMinecartEntity(this)
-            else -> throw IllegalArgumentException("Entities of this type cannot be created with this function")
-        }
-
-        internalEntities.add(entity)
-
-        @Suppress("UNCHECKED_CAST")
-        return entity as T
-    }
 
     fun createPlayerEntity(player: UranosPlayer) =
         UranosPlayerEntity(this, player).also { internalEntities.add(it) }

uranos-server/src/main/kotlin/space/uranos/entity/EntityMetadataSynchronizer.kt

@@ -0,0 +1,11 @@
+package space.uranos.entity
+
+class EntityMetadataSynchronizer(val entity: UranosEntity) {
+    init {
+//        println(entity::class.allSuperclasses)
+    }
+
+    fun tick() {
+
+    }
+}

uranos-server/src/main/kotlin/space/uranos/entity/UranosEntity.kt

@@ -23,8 +23,6 @@ import java.util.UUID
 import java.util.WeakHashMap
 
 sealed class UranosEntity(server: UranosServer) : Entity {
-    override fun belongsToChunk(key: Chunk.Key): Boolean = key == chunkKey
-
     override val numericID: Int = server.claimEntityID()
     override val uuid: UUID = UUID.randomUUID()
 
@@ -65,19 +63,31 @@ sealed class UranosEntity(server: UranosServer) : Entity {
         }
     }
 
-    override fun toString(): String = "Entity($uuid)"
+    override var glowing: Boolean = false
+    override var ignoreGravity: Boolean = false
+    override var invisible: Boolean = false
+    override var silent: Boolean = false
+
+    override fun toString(): String = "Entity($uuid)"
+    override fun belongsToChunk(key: Chunk.Key): Boolean = key == chunkKey
 
-    abstract suspend fun tick()
     abstract val chunkKey: Chunk.Key
 
     protected val container = TickSynchronizationContainer()
 
-    protected fun sendSpawnAndDestroyPackets() {
+    private fun sendSpawnAndDestroyPackets() {
         if (addedViewers.isNotEmpty()) createSpawnPacket().let { packet -> addedViewers.forEach { it.session.send(packet) } }
         if (removedViewers.isNotEmpty()) DestroyEntitiesPacket(arrayOf(numericID)).let { packet -> removedViewers.forEach { it.session.send(packet) } }
     }
 
-    protected fun finishTick() {
+    @Suppress("LeakingThis")
+    private val metadataSynchronizer = EntityMetadataSynchronizer(this)
+
+    open suspend fun tick() {
+        container.tick()
+        metadataSynchronizer.tick()
+
+        sendSpawnAndDestroyPackets()
         addedViewers.clear()
         removedViewers.clear()
     }
@@ -106,8 +116,6 @@ abstract class UranosNotHasMovableHeadLivingEntity(server: UranosServer) : Urano
     private var lastSentPitch: Float = 0f
 
     final override suspend fun tick() {
-        container.tick()
-
         val viewersWithoutAdded = viewers.subtract(addedViewers)
         if (viewersWithoutAdded.isNotEmpty()) {
             val packet = createMovementPacket()
@@ -119,8 +127,7 @@ abstract class UranosNotHasMovableHeadLivingEntity(server: UranosServer) : Urano
         if (this is PitchRotatable) lastSentPitch = pitch
         if (this is YawRotatable) lastSentYaw = yaw
 
-        sendSpawnAndDestroyPackets()
+        super.tick()
-        finishTick()
     }
 
     private fun createMovementPacket(): OutgoingPacket? = createNotHasMovableHeadMovementPacket(position, lastSentPosition, lastSentYaw, lastSentPitch)
@@ -138,8 +145,6 @@ abstract class UranosHasMovableHeadLivingEntity(server: UranosServer) : UranosLi
         }
 
     final override suspend fun tick() {
-        container.tick()
-
         val viewersWithoutAdded = viewers.subtract(addedViewers)
         if (viewersWithoutAdded.isNotEmpty()) {
             val packets = createMovementPackets()
@@ -152,8 +157,7 @@ abstract class UranosHasMovableHeadLivingEntity(server: UranosServer) : UranosLi
         oldHeadPitch = headPitch
         oldHeadYaw = headYaw
 
-        sendSpawnAndDestroyPackets()
+        super.tick()
-        finishTick()
     }
 
     private var oldPosition: Position = Position.ZERO
@@ -216,8 +220,6 @@ abstract class UranosObjectEntity(server: UranosServer) : UranosEntity(server),
     private var lastSentPitch: Float = 0f
 
     final override suspend fun tick() {
-        container.tick()
-
         val viewersWithoutAdded = viewers.subtract(addedViewers)
         if (viewersWithoutAdded.isNotEmpty()) {
             val packet = createMovementPacket()
@@ -228,9 +230,9 @@ abstract class UranosObjectEntity(server: UranosServer) : UranosEntity(server),
 
         if (this is PitchRotatable) lastSentPitch = pitch
         if (this is YawRotatable) lastSentYaw = yaw
+        lastSentPosition = position
 
-        sendSpawnAndDestroyPackets()
+        super.tick()
-        finishTick()
     }
 
     private fun createMovementPacket(): OutgoingPacket? = createNotHasMovableHeadMovementPacket(position, lastSentPosition, lastSentYaw, lastSentPitch)
@@ -247,8 +249,6 @@ class UranosPaintingEntity(
     private var lastSentTopLeftLocation: VoxelLocation = topLeftLocation
 
     override suspend fun tick() {
-        container.tick()
-
         if (lastSentTopLeftLocation != topLeftLocation) {
             val viewersWithoutAdded = viewers.subtract(addedViewers)
             if (viewersWithoutAdded.isNotEmpty()) {
@@ -269,8 +269,7 @@ class UranosPaintingEntity(
 
         lastSentTopLeftLocation = topLeftLocation
 
-        sendSpawnAndDestroyPackets()
+        super.tick()
-        finishTick()
     }
 }
 

uranos-server/src/main/kotlin/space/uranos/entity/UranosMinecartEntity.kt

@@ -1,12 +1,10 @@
-package space.uranos.entity.impl
+package space.uranos.entity
 
 import space.uranos.UranosServer
-import space.uranos.entity.MinecartEntity
-import space.uranos.entity.UranosObjectEntity
 import space.uranos.util.numbers.validatePitch
 import space.uranos.util.numbers.validateYaw
 
-class UranosMinecartEntity(server: UranosServer) : UranosObjectEntity(server), MinecartEntity {
+abstract class UranosMinecartEntity(server: UranosServer) : UranosObjectEntity(server), MinecartEntity {
     override var yaw: Float = 0f
         set(value) {
             validateYaw(value); field = value
@@ -16,4 +14,8 @@ class UranosMinecartEntity(server: UranosServer) : UranosObjectEntity(server), M
         set(value) {
             validatePitch(value); field = value
         }
+
+    override val shakingPower: Int = 0
+    override val shakingDirection: Int = 1
+    override val shakingMultiplier: Float = 0f
 }

uranos-server/src/main/kotlin/space/uranos/entity/impl/UranosRideableMinecartEntity.kt

@@ -0,0 +1,11 @@
+package space.uranos.entity.impl
+
+import space.uranos.UranosServer
+import space.uranos.entity.RideableMinecartEntity
+import space.uranos.entity.UranosMinecartEntity
+import space.uranos.world.block.Block
+
+class UranosRideableMinecartEntity(server: UranosServer) : UranosMinecartEntity(server), RideableMinecartEntity {
+    override val customBlock: Block? = null
+    override val blockOffset: Int = 6
+}

uranos-server/src/main/kotlin/space/uranos/net/LoginAndJoinProcedure.kt

@@ -68,6 +68,7 @@ class LoginAndJoinProcedure(val session: UranosSession) {
         val result = AuthenticationHelper.authenticate(hashString, state.username)
 
         session.sendNow(SetCompressionPacket(session.server.config.packetCompressionThreshold))
+        // TODO: Handle disconnect errors
         session.enableCompressionCodec()
 
         session.sendNow(LoginSuccessPacket(result.uuid, result.username))

uranos-server/src/main/kotlin/space/uranos/net/PacketsAdapter.kt

@@ -18,6 +18,7 @@ class PacketsAdapter(val session: UranosSession) {
     private val packetsForNextTick = ArrayList<OutgoingPacket>()
 
     suspend fun tick() {
+        // TODO: Fix ConcurrentModificationException
         packetsForNextTick.forEach { send(it) }
         packetsForNextTick.clear()
     }

uranos-server/src/main/kotlin/space/uranos/net/UranosSession.kt

@@ -125,6 +125,7 @@ class UranosSession(val channel: io.netty.channel.Channel, val server: UranosSer
             if (!expected && currentProtocol != HandshakingProtocol && currentProtocol != StatusProtocol)
                 logger trace "The client disconnected unexpectedly"
 
+            // TODO: Remove the player entity and send PlayerInfo packet
             packetsAdapter.stopProcessingIncomingPackets()
             coroutineContext.cancel(DisconnectedCancellationException())
             state = State.Disconnected