Seat events, and everything needed to get there

- Added support for seat enter and exit events and a test for them
- Added support for entering and exiting seat from code
- Changed the Id property of ECS objects to non-abstract, requiring it in the constructor, so that the Player class can inherit EcsObjectBase
- Added a weird constructor to EcsObjectBase that allows running code to determine the object Id
- Added interface for engines that receive entity functions
- Exposed the entity submission scheduler and removed it from FullGameFields because it moved from there
- Made the Game.Enter event only fire after the first entity submission so the game is fully initialized and the local player exists
- Added all seat groups to the dictionary

TechbloxModdingAPI/App/GameGameEngine.cs

@@ -1,5 +1,4 @@
-using System;
+using System.Collections.Generic;
-using System.Collections.Generic;
 
 using RobocraftX.Common;
 using RobocraftX.Schedulers;
@@ -11,6 +10,7 @@ using RobocraftX.Blocks;
 using RobocraftX.ScreenshotTaker;
 using TechbloxModdingAPI.Blocks;
 using TechbloxModdingAPI.Engines;
+using TechbloxModdingAPI.Tasks;
 using TechbloxModdingAPI.Utility;
 
 namespace TechbloxModdingAPI.App
@@ -35,6 +35,12 @@ namespace TechbloxModdingAPI.App
 
 		public void Ready()
 		{
+			EnteringGame().RunOn(Scheduler.leanRunner);
+		}
+
+		private IEnumerator<TaskContract> EnteringGame()
+		{
+			yield return new WaitForSubmissionEnumerator(GameLoadedEnginePatch.Scheduler).Continue();
 			EnterGame.Invoke(this, new GameEventArgs { GameName = GameMode.SaveGameDetails.Name, GamePath = GameMode.SaveGameDetails.Folder });
 			IsInGame = true;
 		}
@@ -100,34 +106,23 @@ namespace TechbloxModdingAPI.App
         {
 	        var allBlocks = entitiesDB.QueryEntities<BlockTagEntityStruct>();
 	        List<EGID> blockEGIDs = new List<EGID>();
-			if (filter == BlockIDs.Invalid)
-			{
 	        foreach (var (blocks, _) in allBlocks)
 	        {
-					var buffer = blocks.ToBuffer().buffer;
+		        var (buffer, count) = blocks.ToBuffer();
-					for (int i = 0; i < buffer.capacity; i++)
+		        for (int i = 0; i < count; i++)
+		        {
+			        uint dbid;
+			        if (filter == BlockIDs.Invalid)
+				        dbid = (uint)filter;
+			        else
+				        dbid = entitiesDB.QueryEntity<DBEntityStruct>(buffer[i].ID).DBID;
+			        if (dbid == (ulong)filter)
 				        blockEGIDs.Add(buffer[i].ID);
 		        }
-
-				return blockEGIDs.ToArray();
-			}
-			else
-			{
-				foreach (var (blocks, _) in allBlocks)
-				{
-					var array = blocks.ToBuffer().buffer;
-					for (var index = 0; index < array.capacity; index++)
-					{
-						var block = array[index];
-						uint dbid = entitiesDB.QueryEntity<DBEntityStruct>(block.ID).DBID;
-						if (dbid == (ulong) filter)
-							blockEGIDs.Add(block.ID);
-					}
 	        }
 
 	        return blockEGIDs.ToArray();
         }
-		}
 
         public void EnableScreenshotTaker()
 		{

TechbloxModdingAPI/Block.cs

@@ -99,12 +99,16 @@ namespace TechbloxModdingAPI
 				{CommonExclusiveGroups.ENGINE_BLOCK_BUILD_GROUP, (id => new Engine(id), typeof(Engine))},
 				{CommonExclusiveGroups.LOGIC_BLOCK_GROUP, (id => new LogicGate(id), typeof(LogicGate))},
 				{CommonExclusiveGroups.PISTON_BLOCK_GROUP, (id => new Piston(id), typeof(Piston))},
-				{SeatGroups.PASSENGER_BLOCK_BUILD_GROUP, (id => new Seat(id), typeof(Seat))},
-				{SeatGroups.PILOTSEAT_BLOCK_BUILD_GROUP, (id => new Seat(id), typeof(Seat))},
 				{CommonExclusiveGroups.SERVO_BLOCK_GROUP, (id => new Servo(id), typeof(Servo))},
 				{CommonExclusiveGroups.WHEELRIG_BLOCK_BUILD_GROUP, (id => new WheelRig(id), typeof(WheelRig))}
 			};
 
+		static Block()
+		{
+			foreach (var group in SeatGroups.SEATS_BLOCK_GROUPS) // Adds driver and passenger seats, occupied and unoccupied
+				GroupToConstructor.Add(group, (id => new Seat(id), typeof(Seat)));
+		}
+
 		/// <summary>
 		/// Returns a correctly typed instance of this block. The instances are shared for a specific block.
 		/// If an instance is no longer referenced a new instance is returned.
@@ -126,9 +130,8 @@ namespace TechbloxModdingAPI
 				: GetInstance(egid, e => new Block(e));
 		}
 
-		public Block(EGID id)
+		public Block(EGID id) : base(id)
 		{
-			Id = id;
 			Type expectedType;
 			if (GroupToConstructor.ContainsKey(id.groupID) &&
 			    !GetType().IsAssignableFrom(expectedType = GroupToConstructor[id.groupID].Type))
@@ -156,17 +159,18 @@ namespace TechbloxModdingAPI
 		/// <param name="player">The player who placed the block</param>
 		/// <param name="force">Place even if not in build mode</param>
 		public Block(BlockIDs type, float3 position, bool autoWire = false, Player player = null, bool force = false)
+			: base(block =>
 			{
 				if (!PlacementEngine.IsInGame || !GameState.IsBuildMode() && !force)
 					throw new BlockException("Blocks can only be placed in build mode.");
 				var initializer = PlacementEngine.PlaceBlock(type, position, player, autoWire);
-			Id = initializer.EGID;
+				block.InitData = initializer;
-			InitData = initializer;
+				Placed += ((Block)block).OnPlacedInit;
-			Placed += OnPlacedInit;
+				return initializer.EGID;
+			})
+		{
 		}
 
-		public override EGID Id { get; }
-
 		private EGID copiedFrom;
 
 		/// <summary>

TechbloxModdingAPI/BlockGroup.cs

@@ -19,17 +19,16 @@ namespace TechbloxModdingAPI
     public class BlockGroup : EcsObjectBase, ICollection<Block>, IDisposable
     {
         internal static BlueprintEngine _engine = new BlueprintEngine();
-        public override EGID Id { get; }
         private readonly Block sourceBlock;
         private readonly List<Block> blocks;
         private float3 position, rotation;
         internal bool PosAndRotCalculated;
 
-        internal BlockGroup(int id, Block block)
+        internal BlockGroup(int id, Block block) : base(new EGID((uint)id,
+            BlockGroupExclusiveGroups.BlockGroupEntityGroup))
         {
             if (id == BlockGroupUtility.GROUP_UNASSIGNED)
                 throw new BlockException("Cannot create a block group for blocks without a group!");
-            Id = new EGID((uint) id, BlockGroupExclusiveGroups.BlockGroupEntityGroup);
             sourceBlock = block;
             blocks = new List<Block>(GetBlocks());
             Block.Removed += OnBlockRemoved;

TechbloxModdingAPI/Blocks/Wire.cs

@@ -76,10 +76,11 @@ namespace TechbloxModdingAPI.Blocks
         /// <param name="startPort">Starting port number, or guess if omitted.</param>
         /// <param name="endPort">Ending port number, or guess if omitted.</param>
         /// <exception cref="WireInvalidException">Guessing failed or wire does not exist.</exception>
-        public Wire(Block start, Block end, byte startPort = Byte.MaxValue, byte endPort = Byte.MaxValue)
+        public Wire(Block start, Block end, byte startPort = Byte.MaxValue, byte endPort = Byte.MaxValue) : base(ecs =>
         {
-            startBlockEGID = start.Id;
+            var th = (Wire)ecs;
-            endBlockEGID = end.Id;
+            th.startBlockEGID = start.Id;
+            th.endBlockEGID = end.Id;
             bool flipped = false;
             // find block ports
             EGID wire = signalEngine.MatchBlocksToWire(start.Id, end.Id, startPort, endPort);
@@ -94,12 +95,16 @@ namespace TechbloxModdingAPI.Blocks
 
             if (wire != default)
             {
-                Construct(start.Id, end.Id, startPort, endPort, wire, flipped);
+                th.Construct(start.Id, end.Id, startPort, endPort, wire, flipped);
             }
             else
             {
                 throw new WireInvalidException("Wire not found");
             }
+
+            return th.wireEGID;
+        })
+        {
         }
 
         /// <summary>
@@ -116,7 +121,7 @@ namespace TechbloxModdingAPI.Blocks
         {
         }
 
-        private Wire(EGID startBlock, EGID endBlock, byte startPort, byte endPort, EGID wire, bool inputToOutput)
+        private Wire(EGID startBlock, EGID endBlock, byte startPort, byte endPort, EGID wire, bool inputToOutput) : base(wire)
         {
             Construct(startBlock, endBlock, startPort, endPort, wire, inputToOutput);
         }
@@ -139,7 +144,7 @@ namespace TechbloxModdingAPI.Blocks
         /// Construct a wire object from an existing wire connection.
         /// </summary>
         /// <param name="wireEgid">The wire ID.</param>
-        public Wire(EGID wireEgid)
+        public Wire(EGID wireEgid) : base(wireEgid)
         {
             WireEntityStruct wire = signalEngine.GetWire(wireEGID);
             Construct(wire.sourceBlockEGID, wire.destinationBlockEGID, wire.sourcePortUsage, wire.destinationPortUsage,
@@ -151,14 +156,6 @@ namespace TechbloxModdingAPI.Blocks
         {
         }
 
-        /// <summary>
-        /// The wire's in-game id.
-        /// </summary>
-        public override EGID Id
-        {
-            get => wireEGID;
-        }
-
         /// <summary>
         /// The wire's signal value, as a float.
         /// </summary>

TechbloxModdingAPI/Cluster.cs

@@ -10,11 +10,8 @@ namespace TechbloxModdingAPI
     /// </summary>
     public class Cluster : EcsObjectBase
     {
-        public override EGID Id { get; }
+        public Cluster(EGID id) : base(id)
-
-        public Cluster(EGID id)
         {
-            Id = id;
         }
 
         public Cluster(uint id) : this(new EGID(id, CommonExclusiveGroups.SIMULATION_CLUSTERS_GROUP))

TechbloxModdingAPI/EcsObjectBase.cs

@@ -10,7 +10,7 @@ namespace TechbloxModdingAPI
 {
     public abstract class EcsObjectBase
     {
-        public abstract EGID Id { get; } //Abstract to support the 'place' Block constructor
+        public EGID Id { get; }
         
         private static readonly Dictionary<Type, WeakDictionary<EGID, EcsObjectBase>> _instances =
             new Dictionary<Type, WeakDictionary<EGID, EcsObjectBase>>();
@@ -39,7 +39,19 @@ namespace TechbloxModdingAPI
             return (T)instance;
         }
 
-        protected EcsObjectBase()
+        protected EcsObjectBase(EGID id)
+        {
+            if (!_instances.TryGetValue(GetType(), out var dict))
+            {
+                dict = new WeakDictionary<EGID, EcsObjectBase>();
+                _instances.Add(GetType(), dict);
+            }
+            if (!dict.ContainsKey(id)) // Multiple instances may be created
+                dict.Add(id, this);
+            Id = id;
+        }
+
+        protected EcsObjectBase(Func<EcsObjectBase, EGID> initializer)
         {
             if (!_instances.TryGetValue(GetType(), out var dict))
             {
@@ -47,11 +59,9 @@ namespace TechbloxModdingAPI
                 _instances.Add(GetType(), dict);
             }
 
-            // ReSharper disable VirtualMemberCallInConstructor
+            var id = initializer(this);
-            // The ID should not depend on the constructor
+            if (!dict.ContainsKey(id)) // Multiple instances may be created
-            if (!dict.ContainsKey(Id)) // Multiple instances may be created
+                dict.Add(id, this);
-                dict.Add(Id, this);
-            // ReSharper enable VirtualMemberCallInConstructor
         }
 
         #region ECS initializer stuff

TechbloxModdingAPI/Engines/EnginePatches.cs

@@ -5,6 +5,7 @@ using RobocraftX.CR.MainGame;
 using RobocraftX.FrontEnd;
 using RobocraftX.StateSync;
 using Svelto.ECS;
+using Svelto.ECS.Schedulers;
 using TechbloxModdingAPI.Utility;
 
 namespace TechbloxModdingAPI.Engines
@@ -12,10 +13,12 @@ namespace TechbloxModdingAPI.Engines
 	[HarmonyPatch]
 	class GameLoadedEnginePatch
 	{
+		public static EntitiesSubmissionScheduler Scheduler { get; private set; }
 		public static void Postfix(StateSyncRegistrationHelper stateSyncReg)
 		{
 			// register all game engines, including deterministic
 			GameEngineManager.RegisterEngines(stateSyncReg);
+			Scheduler = stateSyncReg.enginesRoot.scheduler;
 		}
 
 		public static MethodBase TargetMethod()

TechbloxModdingAPI/Engines/IFunEngine.cs

@@ -0,0 +1,9 @@
+using Svelto.ECS;
+
+namespace TechbloxModdingAPI.Engines
+{
+    public interface IFunEngine : IApiEngine
+    {
+        public IEntityFunctions Functions { set; }
+    }
+}

TechbloxModdingAPI/Player.Events.cs

@@ -0,0 +1,30 @@
+using System;
+using Svelto.ECS;
+using TechbloxModdingAPI.Blocks;
+using TechbloxModdingAPI.Utility;
+
+namespace TechbloxModdingAPI
+{
+    public partial class Player
+    {
+        internal WrappedHandler<PlayerSeatEventArgs> seatEntered;
+        public event EventHandler<PlayerSeatEventArgs> SeatEntered
+        {
+            add => seatEntered += value;
+            remove => seatEntered -= value;
+        }
+
+        internal WrappedHandler<PlayerSeatEventArgs> seatExited;
+        public event EventHandler<PlayerSeatEventArgs> SeatExited
+        {
+            add => seatExited += value;
+            remove => seatExited -= value;
+        }
+    }
+
+    public struct PlayerSeatEventArgs
+    {
+        public EGID SeatId;
+        public Seat Seat => (Seat)Block.New(SeatId);
+    }
+}

TechbloxModdingAPI/Player.cs

@@ -20,10 +20,11 @@ namespace TechbloxModdingAPI
     /// <summary>
     /// An in-game player character. Any Leo you see is a player.
     /// </summary>
-    public class Player : IEquatable<Player>, IEquatable<EGID>
+    public partial class Player : EcsObjectBase, IEquatable<Player>, IEquatable<EGID>
-    { //TODO: Inherit EcsObjectBase and make Id an EGID, useful for caching
+    {
         // static functionality
 		private static PlayerEngine playerEngine = new PlayerEngine();
+		private static PlayerEventsEngine playerEventsEngine = new PlayerEventsEngine();
 		private static Player localPlayer;
 
         /// <summary>
@@ -79,7 +80,7 @@ namespace TechbloxModdingAPI
         /// Initializes a new instance of the <see cref="T:TechbloxModdingAPI.Player"/> class.
         /// </summary>
         /// <param name="id">The player's unique identifier.</param>
-        public Player(uint id)
+        public Player(uint id) : base(new EGID(id, CharacterExclusiveGroups.OnFootGroup))
         {
             this.Id = id;
             if (!Exists(id))
@@ -93,21 +94,30 @@ namespace TechbloxModdingAPI
         /// Initializes a new instance of the <see cref="T:TechbloxModdingAPI.Player"/> class.
         /// </summary>
         /// <param name="player">The player type. Chooses the first available player matching the criteria.</param>
-        public Player(PlayerType player)
+        public Player(PlayerType player) : base(ecs =>
         {
+	        uint id;
 	        switch (player)
 	        {
 		        case PlayerType.Local:
-                    this.Id = playerEngine.GetLocalPlayer();
+			        id = playerEngine.GetLocalPlayer();
 			        break;
 		        case PlayerType.Remote:
-                    this.Id = playerEngine.GetRemotePlayer();
+			        id = playerEngine.GetRemotePlayer();
+			        break;
+		        default:
+			        id = uint.MaxValue;
 			        break;
 	        }
-            if (this.Id == uint.MaxValue)
+
+	        if (id == uint.MaxValue)
 	        {
 		        throw new PlayerNotFoundException($"No player of {player} type exists");
 	        }
+
+	        return new EGID(id, CharacterExclusiveGroups.OnFootGroup);
+        })
+        {
 	        this.Type = player;
         }
 
@@ -124,7 +134,7 @@ namespace TechbloxModdingAPI
         /// The player's unique identifier.
         /// </summary>
         /// <value>The identifier.</value>
-		public uint Id { get; }
+		public new uint Id { get; }
 
         /// <summary>
         /// The player's current position.
@@ -425,6 +435,16 @@ namespace TechbloxModdingAPI
 			playerEngine.SetLocation(Id, location, exitSeat: exitSeat);
 		}
 
+        public void EnterSeat(Seat seat)
+        {
+	        playerEngine.EnterSeat(Id, seat.Id);
+        }
+
+        public void ExitSeat()
+        {
+	        playerEngine.ExitSeat(Id);
+        }
+        
         /// <summary>
         /// Returns the block the player is currently looking at in build mode.
         /// </summary>
@@ -507,6 +527,7 @@ namespace TechbloxModdingAPI
         internal static void Init()
 		{
 			Utility.GameEngineManager.AddGameEngine(playerEngine);
+			Utility.GameEngineManager.AddGameEngine(playerEventsEngine);
 		}
     }
 }

TechbloxModdingAPI/Players/PlayerEngine.cs

@@ -1,4 +1,5 @@
-using System.Runtime.CompilerServices;
+using System;
+using System.Runtime.CompilerServices;
 
 using RobocraftX.Character;
 using RobocraftX.Character.Movement;
@@ -8,10 +9,13 @@ using RobocraftX.CR.MachineEditing.BoxSelect;
 using RobocraftX.Physics;
 using RobocraftX.Blocks.Ghost;
 using Gamecraft.GUI.HUDFeedbackBlocks;
+using RobocraftX.Blocks;
+using RobocraftX.PilotSeat;
 using Svelto.ECS;
 using Techblox.Camera;
 using Unity.Mathematics;
 using Svelto.ECS.DataStructures;
+using Svelto.ECS.EntityStructs;
 using Techblox.BuildingDrone;
 
 using TechbloxModdingAPI.Engines;
@@ -19,7 +23,7 @@ using TechbloxModdingAPI.Utility;
 
 namespace TechbloxModdingAPI.Players
 {
-	internal class PlayerEngine : IApiEngine, IFactoryEngine
+	internal class PlayerEngine : IFunEngine
 	{
 		public string Name { get; } = "TechbloxModdingAPIPlayerGameEngine";
 
@@ -27,7 +31,7 @@ namespace TechbloxModdingAPI.Players
 
 		public bool isRemovable => false;
 
-		public IEntityFactory Factory { set; private get; }
+		public IEntityFunctions Functions { get; set; }
 
 		private bool isReady = false;
 
@@ -101,9 +105,7 @@ namespace TechbloxModdingAPI.Players
 				return false;
 			if (group == CharacterExclusiveGroups.InPilotSeatGroup && exitSeat)
 			{
-				EGID egid = new EGID(playerId, group);
+				ExitSeat(playerId);
-				entitiesDB.QueryEntity<CharacterPilotSeatEntityStruct>(egid).instantExit = true;
-				entitiesDB.PublishEntityChange<CharacterPilotSeatEntityStruct>(egid);
 			}
 			rbesOpt.Get().position = location;
 			return true;
@@ -183,12 +185,12 @@ namespace TechbloxModdingAPI.Players
         {
 	        if (!entitiesDB.Exists<BoxSelectStateEntityStruct>(playerid,
 		        BoxSelectExclusiveGroups.BoxSelectVolumeExclusiveGroup))
-		        return new Block[0];
+		        return Array.Empty<Block>();
 	        var state = entitiesDB.QueryEntity<BoxSelectStateEntityStruct>(playerid,
 		        BoxSelectExclusiveGroups.BoxSelectVolumeExclusiveGroup);
 	        var blocks = entitiesDB.QueryEntity<SelectedBlocksStruct>(playerid,
 		        BoxSelectExclusiveGroups.BoxSelectVolumeExclusiveGroup);
-	        if (!state.active) return new Block[0];
+	        if (!state.active) return Array.Empty<Block>();
 	        var pointer = (EGID*) blocks.selectedBlocks.ToPointer();
 	        var ret = new Block[blocks.count];
 	        for (int j = 0; j < blocks.count; j++)
@@ -199,5 +201,31 @@ namespace TechbloxModdingAPI.Players
 
 	        return ret;
         }
+
+        public void EnterSeat(uint playerId, EGID seatId)
+        {
+	        PilotSeatGroupUtils.SwapTagTo<OCCUPIED_TAG>(Functions, seatId);
+	        var opt = GetCharacterStruct<CharacterPilotSeatEntityStruct>(playerId, out var group);
+	        if (!opt) return;
+	        ref CharacterPilotSeatEntityStruct charSeat = ref opt.Get();
+	        var charId = new EGID(playerId, group);
+	        charSeat.pilotSeatEntity = entitiesDB.GetEntityReference(seatId);
+	        charSeat.entryPositionOffset =
+		        entitiesDB.QueryEntity<PositionEntityStruct>(charId).position -
+		        entitiesDB.QueryEntity<PositionEntityStruct>(seatId).position;
+	        ref var seat = ref entitiesDB.QueryEntity<PilotSeatEntityStruct>(seatId);
+	        seat.occupyingCharacter = entitiesDB.GetEntityReference(charId);
+	        charSeat.followCam = entitiesDB.QueryEntity<SeatFollowCamComponent>(seatId).followCam;
+	        Functions.SwapEntityGroup<CharacterEntityDescriptor>(charId, CharacterExclusiveGroups.InPilotSeatGroup);
+        }
+
+        public void ExitSeat(uint playerId)
+        {
+	        EGID egid = new EGID(playerId, CharacterExclusiveGroups.InPilotSeatGroup);
+	        var opt = entitiesDB.QueryEntityOptional<CharacterPilotSeatEntityStruct>(egid);
+	        if (!opt) return;
+	        opt.Get().instantExit = true;
+	        entitiesDB.PublishEntityChange<CharacterPilotSeatEntityStruct>(egid);
+        }
 	}
 }

TechbloxModdingAPI/Players/PlayerEventsEngine.cs

@@ -0,0 +1,33 @@
+using RobocraftX.Character;
+using RobocraftX.Character.Movement;
+using Svelto.ECS;
+using TechbloxModdingAPI.Engines;
+
+namespace TechbloxModdingAPI.Players
+{
+    public class PlayerEventsEngine : IApiEngine, IReactOnSwap<CharacterPilotSeatEntityStruct>
+    {
+        public void Ready()
+        {
+        }
+
+        public EntitiesDB entitiesDB { get; set; }
+        public void Dispose()
+        {
+        }
+
+        public string Name => "TechbloxModdingAPIPlayerEventsEngine";
+        public bool isRemovable => false;
+
+        public void MovedTo(ref CharacterPilotSeatEntityStruct entityComponent, ExclusiveGroupStruct previousGroup, EGID egid)
+        {
+            var seatId = entityComponent.pilotSeatEntity.ToEGID(entitiesDB);
+            var player = EcsObjectBase.GetInstance(new EGID(egid.entityID, CharacterExclusiveGroups.OnFootGroup),
+                e => new Player(e.entityID));
+            if (previousGroup == CharacterExclusiveGroups.InPilotSeatGroup)
+                player.seatExited.Invoke(this, new PlayerSeatEventArgs { SeatId = seatId});
+            else if (egid.groupID == CharacterExclusiveGroups.InPilotSeatGroup)
+                player.seatEntered.Invoke(this, new PlayerSeatEventArgs { SeatId = seatId });
+        }
+    }
+}

TechbloxModdingAPI/Players/PlayerTests.cs

@@ -1,8 +1,11 @@
-using System;
+using System.Collections.Generic;
 
+using Svelto.Tasks;
+using Svelto.Tasks.Enumerators;
 using Unity.Mathematics;
 
-using TechbloxModdingAPI;
+using TechbloxModdingAPI.App;
+using TechbloxModdingAPI.Blocks;
 using TechbloxModdingAPI.Tests;
 
 namespace TechbloxModdingAPI.Players
@@ -31,6 +34,34 @@ namespace TechbloxModdingAPI.Players
 			Assert.CloseTo(p.Position, float3.zero + 1, "Player is not close to origin+1 despite being teleported there.", "Player.Position is at origin+1.");
 		}
 		
+		[APITestCase(TestType.Game)]
+		public static void SeatEventTestBuild()
+		{
+			Player.LocalPlayer.SeatEntered += Assert.CallsBack<PlayerSeatEventArgs>("SeatEntered");
+			Player.LocalPlayer.SeatExited += Assert.CallsBack<PlayerSeatEventArgs>("SeatExited");
+			Block.PlaceNew(BlockIDs.DriverSeat, -1f);
+		}
+
+		[APITestCase(TestType.SimulationMode)]
+		public static IEnumerator<TaskContract> SeatEventTestSim()
+		{
+			var seats = Game.CurrentGame().GetBlocksInGame(BlockIDs.DriverSeat);
+			if (seats.Length == 0)
+			{
+				Assert.Fail("No driver seat found!");
+				yield break;
+			}
+
+			if (seats[0] is Seat seat)
+				Assert.Errorless(() => Player.LocalPlayer.EnterSeat(seat), "Failed to enter seat.",
+					"Entered seat successfully.");
+			else
+				Assert.Fail("Found a seat that is not a seat!");
+			yield return new WaitForSecondsEnumerator(1).Continue();
+			Assert.Errorless(() => Player.LocalPlayer.ExitSeat(), "Failed to exit seat.",
+				"Exited seat successfully.");
+		}
+
 		[APITestCase(TestType.Menu)]
 		public static void InvalidStateTest()
 		{

TechbloxModdingAPI/SimBody.cs

@@ -14,8 +14,6 @@ namespace TechbloxModdingAPI
     /// </summary>
     public class SimBody : EcsObjectBase, IEquatable<SimBody>, IEquatable<EGID>
     {
-        public override EGID Id { get; }
-
         /// <summary>
         /// The cluster this chunk belongs to, or null if no cluster destruction manager present or the chunk doesn't exist.
         /// Get the SimBody from a Block if possible for good performance here.
@@ -28,9 +26,8 @@ namespace TechbloxModdingAPI
         private Cluster cluster;
         private readonly uint clusterId = uint.MaxValue;
 
-        public SimBody(EGID id)
+        public SimBody(EGID id) : base(id)
         {
-            Id = id;
         }
 
         public SimBody(uint id) : this(new EGID(id, CommonExclusiveGroups.SIMULATION_BODIES_GROUP))

TechbloxModdingAPI/Tests/TechbloxModdingAPIPluginTest.cs

@@ -58,6 +58,14 @@ namespace TechbloxModdingAPI.Tests
 
 			// debug/test handlers
 			Client.EnterMenu += (sender, args) => throw new Exception("Test handler always throws an exception!");
+			Client.EnterMenu += (sender, args) => Console.WriteLine("EnterMenu handler after erroring handler");
+			Game.Enter += (s, a) =>
+			{
+				Player.LocalPlayer.SeatEntered += (sender, args) =>
+					Console.WriteLine($"Player {Player.LocalPlayer} entered seat {args.Seat}");
+				Player.LocalPlayer.SeatExited += (sender, args) =>
+					Console.WriteLine($"Player {Player.LocalPlayer} exited seat {args.Seat}");
+			};
 
 			// debug/test commands
 			if (Dependency.Hell("ExtraCommands"))

TechbloxModdingAPI/Utility/FullGameFields.cs

@@ -72,14 +72,6 @@ namespace TechbloxModdingAPI.Utility
 			}
 		}
 
-		public static SimpleEntitiesSubmissionScheduler _mainGameSubmissionScheduler
-		{
-			get
-			{
-				return (SimpleEntitiesSubmissionScheduler)fgcr?.Field("_sub").Field("_mainGameSubmissionScheduler").GetValue();
-			}
-		}
-
 		public static BuildPhysicsWorld _physicsWorldSystem
 		{
 			get

TechbloxModdingAPI/Utility/GameEngineManager.cs

@@ -26,10 +26,10 @@ namespace TechbloxModdingAPI.Utility
             {
 				Logging.MetaDebugLog($"Registering Game IApiEngine {engine.Name}");
                 _lastEngineRoot.AddEngine(engine);
-				if (typeof(IFactoryEngine).IsAssignableFrom(engine.GetType()))
+				if (engine is IFactoryEngine factoryEngine)
-                {
+                    factoryEngine.Factory = _lastEngineRoot.GenerateEntityFactory();
-					((IFactoryEngine)engine).Factory = _lastEngineRoot.GenerateEntityFactory();
+                if (engine is IFunEngine funEngine)
-                }
+                    funEngine.Functions = _lastEngineRoot.GenerateEntityFunctions();
             }
         }
 
@@ -66,6 +66,7 @@ namespace TechbloxModdingAPI.Utility
             var enginesRoot = helper.enginesRoot;
 			_lastEngineRoot = enginesRoot;
             IEntityFactory factory = enginesRoot.GenerateEntityFactory();
+            IEntityFunctions functions = enginesRoot.GenerateEntityFunctions();
             foreach (var key in _gameEngines.Keys)
             {
                 Logging.MetaDebugLog($"Registering Game IApiEngine {_gameEngines[key].Name}");
@@ -75,6 +76,8 @@ namespace TechbloxModdingAPI.Utility
                     enginesRoot.AddEngine(_gameEngines[key]);
                 if (_gameEngines[key] is IFactoryEngine factEngine)
                     factEngine.Factory = factory;
+                if (_gameEngines[key] is IFunEngine funEngine)
+                    funEngine.Functions = functions;
             }
         }
     }

TechbloxModdingAPI/Utility/MenuEngineManager.cs

@@ -26,10 +26,10 @@ namespace TechbloxModdingAPI.Utility
             {
 				Logging.MetaDebugLog($"Registering Menu IApiEngine {engine.Name}");
                 _lastEngineRoot.AddEngine(engine);
-				if (typeof(IFactoryEngine).IsAssignableFrom(engine.GetType()))
+				if (engine is IFactoryEngine factoryEngine)
-                {
+                    factoryEngine.Factory = _lastEngineRoot.GenerateEntityFactory();
-					((IFactoryEngine)engine).Factory = _lastEngineRoot.GenerateEntityFactory();
+                if (engine is IFunEngine funEngine)
-                }
+                    funEngine.Functions = _lastEngineRoot.GenerateEntityFunctions();
             }
         }
 
@@ -65,14 +65,13 @@ namespace TechbloxModdingAPI.Utility
         {
 			_lastEngineRoot = enginesRoot;
 			IEntityFactory factory = enginesRoot.GenerateEntityFactory();
+            IEntityFunctions functions = enginesRoot.GenerateEntityFunctions();
             foreach (var key in _menuEngines.Keys)
             {
                 Logging.MetaDebugLog($"Registering Menu IApiEngine {_menuEngines[key].Name}");
                 enginesRoot.AddEngine(_menuEngines[key]);
-				if (_menuEngines[key] is IFactoryEngine factEngine)
+				if (_menuEngines[key] is IFactoryEngine factEngine) factEngine.Factory = factory;
-				{
+                if(_menuEngines[key] is IFunEngine funEngine) funEngine.Functions = functions;
-					factEngine.Factory = factory;
-				}
             }
         }
     }