netcode progress, improved handling of missing frames

Content/Settings/EngineSettings/GraphicsSettings.json

@@ -6,8 +6,8 @@
 	"UseVSync": false,
 	"AAQuality": 3,
 	"SSRQuality": 3,
-	"SSAOQuality": 0,
+	"SSAOQuality": 3,
-	"VolumetricFogQuality": 3,
+	"VolumetricFogQuality": 0,
 	"ShadowsQuality": 3,
 	"ShadowMapsQuality": 3,
 	"AllowCSMBlending": true,

Content/Settings/EngineSettings/InputSettings.json

@@ -1,7 +1,7 @@
 {
 	"ID": "8ec53dba4c238bfbea1d62922e612a4d",
 	"TypeName": "FlaxEditor.Content.Settings.InputSettings",
-	"EngineBuild": 6335,
+	"EngineBuild": 6705,
 	"Data": {
 	"ActionMappings": [
 		{
@@ -84,6 +84,8 @@
 			"Gamepad": 0,
 			"PositiveButton": 0,
 			"NegativeButton": 0,
+			"GamepadPositiveButton": 0,
+			"GamepadNegativeButton": 0,
 			"DeadZone": 0.0,
 			"Sensitivity": 0.11,
 			"Gravity": 1.0,
@@ -96,6 +98,8 @@
 			"Gamepad": 0,
 			"PositiveButton": 0,
 			"NegativeButton": 0,
+			"GamepadPositiveButton": 0,
+			"GamepadNegativeButton": 0,
 			"DeadZone": 0.0,
 			"Sensitivity": 0.11,
 			"Gravity": 1.0,
@@ -108,9 +112,11 @@
 			"Gamepad": 0,
 			"PositiveButton": 68,
 			"NegativeButton": 65,
+			"GamepadPositiveButton": 0,
+			"GamepadNegativeButton": 0,
 			"DeadZone": 0.01,
-			"Sensitivity": 5.0,
+			"Sensitivity": 0.0,
-			"Gravity": 5.0,
+			"Gravity": 0.0,
 			"Scale": 1.0,
 			"Snap": true
 		},
@@ -120,9 +126,11 @@
 			"Gamepad": 0,
 			"PositiveButton": 87,
 			"NegativeButton": 83,
+			"GamepadPositiveButton": 0,
+			"GamepadNegativeButton": 0,
 			"DeadZone": 0.01,
-			"Sensitivity": 5.0,
+			"Sensitivity": 0.0,
-			"Gravity": 5.0,
+			"Gravity": 0.0,
 			"Scale": 1.0,
 			"Snap": true
 		},
@@ -132,6 +140,8 @@
 			"Gamepad": 0,
 			"PositiveButton": 39,
 			"NegativeButton": 37,
+			"GamepadPositiveButton": 0,
+			"GamepadNegativeButton": 0,
 			"DeadZone": 0.0,
 			"Sensitivity": 1.0,
 			"Gravity": 800.0,
@@ -144,6 +154,8 @@
 			"Gamepad": 0,
 			"PositiveButton": 38,
 			"NegativeButton": 40,
+			"GamepadPositiveButton": 0,
+			"GamepadNegativeButton": 0,
 			"DeadZone": 0.0,
 			"Sensitivity": 1.0,
 			"Gravity": 800.0,
@@ -156,6 +168,8 @@
 			"Gamepad": 0,
 			"PositiveButton": 0,
 			"NegativeButton": 0,
+			"GamepadPositiveButton": 0,
+			"GamepadNegativeButton": 0,
 			"DeadZone": 0.19,
 			"Sensitivity": 1.0,
 			"Gravity": 1.0,
@@ -168,6 +182,8 @@
 			"Gamepad": 0,
 			"PositiveButton": 0,
 			"NegativeButton": 0,
+			"GamepadPositiveButton": 0,
+			"GamepadNegativeButton": 0,
 			"DeadZone": 0.19,
 			"Sensitivity": 1.0,
 			"Gravity": 1.0,
@@ -180,6 +196,8 @@
 			"Gamepad": 0,
 			"PositiveButton": 0,
 			"NegativeButton": 0,
+			"GamepadPositiveButton": 0,
+			"GamepadNegativeButton": 0,
 			"DeadZone": 0.19,
 			"Sensitivity": 1.0,
 			"Gravity": 1.0,
@@ -192,6 +210,8 @@
 			"Gamepad": 0,
 			"PositiveButton": 0,
 			"NegativeButton": 0,
+			"GamepadPositiveButton": 0,
+			"GamepadNegativeButton": 0,
 			"DeadZone": 0.19,
 			"Sensitivity": 1.0,
 			"Gravity": 1.0,

Content/Settings/EngineSettings/PhysicsSettings.json

@@ -1,7 +1,7 @@
 {
 	"ID": "4bd8a4cc460399b5f1975fbe0a668e3f",
 	"TypeName": "FlaxEditor.Content.Settings.PhysicsSettings",
-	"EngineBuild": 6510,
+	"EngineBuild": 6705,
 	"Data": {
 	"DefaultGravity": {
 		"X": 0.0,
@@ -13,6 +13,7 @@
 	"RestitutionCombineMode": 0,
 	"DisableCCD": false,
 	"BroadPhaseType": 3,
+	"EnableEnhancedDeterminism": false,
 	"SolverType": 0,
 	"MaxDeltaTime": 0.1,
 	"EnableSubstepping": false,

Source/Game/Camera/CameraRender.cs

@@ -137,7 +137,7 @@ public class CameraRender : PostProcessEffect
     private bool lastRescale = false;
     public override void OnUpdate()
     {
-#if FLAX_EDITOR
+/*#if FLAX_EDITOR
         if (Input.GetKeyDown(KeyboardKeys.F7))
         {
             PhysicsSettings physicsSettings = GameSettings.Load<PhysicsSettings>();
@@ -145,7 +145,7 @@ public class CameraRender : PostProcessEffect
             GameSettings.Save(physicsSettings);
             //GameSettings.Apply();
         }
-#endif
+#endif*/
 
         if (lastEnabled != camera.IsActive)
         {

Source/Game/GameMode/NetworkManager_Client.cs

@@ -24,14 +24,17 @@ public static partial class NetworkManager
 
         //var driver = Object.New(typeof(ENetDriver));
         //ClientNetworkDriver = null;
-        NetworkLagDriver driver = Object.New<NetworkLagDriver>();
+
-        driver.Lag = 0f;
+        //INetworkDriver driver = Object.New<ENetDriver>();
+        INetworkDriver driver = Object.New<NetworkLagDriver>();
+        if (driver is NetworkLagDriver networkLagDriver)
+            networkLagDriver.Lag = 50.0f;
         ClientNetworkDriver = driver;
         
 
         client = NetworkPeer.CreatePeer(new NetworkConfig
         {
-            NetworkDriver = driver,
+            NetworkDriver = (Object)driver,
             ConnectionsLimit = MaximumClients,
             MessagePoolSize = 2048,
             MessageSize = MTU,

Source/Game/GameMode/NetworkManager_Server.cs

@@ -22,14 +22,15 @@ public static partial class NetworkManager
 
     public static bool StartServer(bool listenServer = true)
     {
+        Time.Synchronize();
         Cleanup();
         ConnectedClients = new List<NetworkConnection>(MaximumClients);
 
 
-        //INetworkDriver driver = Object.New<ENetDriver>();
+        INetworkDriver driver = Object.New<ENetDriver>();
-        NetworkLagDriver driver = Object.New<NetworkLagDriver>();
+        //NetworkLagDriver driver = Object.New<NetworkLagDriver>();
         if (driver is NetworkLagDriver networkLagDriver)
-            networkLagDriver.Lag = 200f;
+            networkLagDriver.Lag = 50.0f;//200f;
 
         ServerNetworkDriver = driver;
 

Source/Game/GameMode/World.cs

@@ -24,7 +24,7 @@ public enum GameModeMessageType2 : byte
 
 public class PlayerFrame
 {
-    public ulong frame;
+    public ulong frame => inputState.Frame;
     public Float3 position;
     public PlayerInputState2 inputState;
     public PlayerMovementState movementState;
@@ -40,7 +40,7 @@ public interface IClientInfo
 public class World
 {
     public bool IsServer => this is ServerWorld;
-    public bool IsClient => !IsServer;
+    public bool IsClient => this is ClientWorld;
     public ulong Frame { get; protected set; }
     public ulong ServerFrame { get; protected set; } // Last received frame from server
     public float GameTime { get; protected set; } // The join time
@@ -102,17 +102,17 @@ public class World
 
     void OnUpdate()
     {
-        Console.Print("server Update");
+        //Console.Print("server Update");
     }
 
     void OnUpdateLate()
     {
-        Console.Print("server LateUpdate");
+        //Console.Print("server LateUpdate");
     }
 
     void OnFixedUpdate()
     {
-        Console.Print("server FixedUpdate");
+        //Console.Print("server FixedUpdate");
     }
 
     protected void CreateScene(string sceneNamePrefix, string sceneGuid)
@@ -224,14 +224,17 @@ public class World
 
     virtual public bool IsLocalPlayer(uint playerId) => false;
 
+    virtual public ulong GetLastProcessedFrame(uint playerId) => 0;
+
+    virtual public ulong GetLastReceivedFrame(uint playerId) => 0;
+
     public PlayerFrame GetPlayerFrame(uint playerId, ulong frame)
     {
         IClientInfo player = GetClient(playerId);
         PlayerFrame playerFrame = player.FrameHistory[frame % 120];
-        if (playerFrame.frame != frame)
+        if (playerFrame.inputState.Frame == frame || playerFrame.movementState.frame == frame)
-            return null;
+            return playerFrame;
-
+        return null;
-        return playerFrame;
     }
 
     public bool HasPlayerFrame(uint playerId, ulong frame) => GetPlayerFrame(playerId, frame) != null;
@@ -248,8 +251,9 @@ public class World
         IClientInfo player = GetClient(playerId);
 
         PlayerFrame playerFrame = player.FrameHistory[frame % 120];
-        if (playerFrame.frame == frame)
+        /*if (playerFrame.frame == frame)
         {
+            var old = playerFrame.inputState with { Frame = inputState.Frame };
             playerFrame.inputState = inputState with
             {
                 ViewDelta = playerFrame.inputState.ViewDelta + inputState.ViewDelta,
@@ -258,11 +262,23 @@ public class World
                 Attack = playerFrame.inputState.Attack || inputState.Attack,
                 Jump = playerFrame.inputState.Jump || inputState.Jump,
             };
+
+            if (old != playerFrame.inputState)
+                old = old;
         }
-        else
+        else*/
             playerFrame.inputState = inputState;
+        playerFrame.inputState.Frame = frame;
+        //playerFrame.movementState = movementState;
+        //playerFrame.frame = frame;
+    }
+
+    virtual public void UpdatePlayerState(uint playerId, ulong frame, PlayerMovementState movementState)
+    {
+        IClientInfo player = GetClient(playerId);
+        PlayerFrame playerFrame = player.FrameHistory[frame % 120];
         playerFrame.movementState = movementState;
-        playerFrame.frame = frame;
+        playerFrame.movementState.frame = frame;
     }
 }
 
@@ -275,12 +291,17 @@ file class ServerWorld : World
         public PlayerFrame[] FrameHistory { get; set; } = new PlayerFrame[120];
         public ulong LastReceivedFrame = 0;
         public ulong LastSentDeltaFrame = 0; // TODO: Accumulate deltas since this frame
+        public ulong LastProcessedFrame = 0; // In case player is lagged behind, these frames should be caught up during next simulation
         public int SendRate = 0; // How many updates the client wants to receive per second
 
         public ClientInfo()
         {
             for (int i = 0; i < FrameHistory.Length; i++)
+            {
                 FrameHistory[i] = new PlayerFrame();
+                FrameHistory[i].inputState.Frame = ulong.MaxValue;
+                FrameHistory[i].movementState.frame = ulong.MaxValue;
+            }
         }
     }
 
@@ -306,8 +327,14 @@ file class ServerWorld : World
 
     protected override void OnLateUpdate()
     {
-        Console.Print("server LateFixedUpdate");
+        //Console.Print("server LateFixedUpdate");
         base.OnLateUpdate();
+
+        foreach (var client in _clients.Values)
+        {
+            // We assume all the scripts have processed the frames during this cycle
+            client.LastProcessedFrame = client.LastReceivedFrame;
+        }
     }
 
     public bool OnMessage(ref NetworkEvent networkEvent)
@@ -369,9 +396,10 @@ file class ServerWorld : World
             {
                 PlayerInputState2 inputState; //?
 
-                ulong receivedFrame = networkEvent.Message.ReadUInt64();
+                ulong receivedFrame = inputState.Frame = networkEvent.Message.ReadUInt64();
-                uint reportedPlayerId = networkEvent.Message.ReadUInt32();
+                uint playerId = networkEvent.Message.ReadUInt32();
-                inputState.Frame = receivedFrame;
+                float time = networkEvent.Message.ReadSingle();
+                float delay = Time.TimeSinceStartup - time;
                 inputState.ViewDelta.X = networkEvent.Message.ReadSingle();
                 inputState.ViewDelta.Y = networkEvent.Message.ReadSingle();
                 inputState.MoveForward = networkEvent.Message.ReadSingle();
@@ -379,22 +407,42 @@ file class ServerWorld : World
                 inputState.Attack = networkEvent.Message.ReadBoolean();
                 inputState.Jump = networkEvent.Message.ReadBoolean();
 
-                Console.Print($"server receive client frame {receivedFrame}, current server frame {Frame}");
+                //Console.Print("recv: " + receivedFrame.ToString());
+
+                ClientInfo player = GetClient(playerId) as ClientInfo;
+                if (receivedFrame <= player.LastReceivedFrame)
+                {
+                    if (receivedFrame < player.LastProcessedFrame)
+                    {
+                        Console.PrintWarning($"Dropping late frame from client: {receivedFrame}, last processed: {player.LastProcessedFrame}");
+                        break;
+                    }
+                    else
+                    {
+                        //Console.PrintWarning($"Out-of-order frame received from client: {receivedFrame}, latest: {player.LastReceivedFrame}");
+                    }
+                }
+                player.LastReceivedFrame = Math.Max(receivedFrame, player.LastReceivedFrame);
+                //if (player.LastProcessedFrame == 0)
+                //    player.LastProcessedFrame = receivedFrame - 1;
+
+                //Console.Print($"server receive client frame {receivedFrame}, current server frame {Frame}");
                 var asdf = receivedFrame;
-                receivedFrame = Frame;
+                //receivedFrame = Frame; // TODO: receive all frames from players, simulate all unprocessed frames in next simulation cycle?
 
                 if (inputState.MoveForward != 0)
                     receivedFrame = receivedFrame;
 
-                
+                //Console.Print($"delay: {delay * 1000}ms");
+
                 // Sanity check
-                if (GetPlayerInputState(reportedPlayerId, receivedFrame, out var prevInputState))
+                if (GetPlayerInputState(playerId, receivedFrame, out var prevInputState))
                 {
-                    Console.PrintWarning($"Duplicate frame received from client: {asdf}");
+                    Console.PrintWarning($"Duplicate frame received from client: {asdf}, delay: {delay*1000}ms");
+                    //break;
                 }
 
-                PlayerMovementState movementState = default;
+                UpdatePlayerInputState(playerId, receivedFrame, inputState, default);
-                UpdatePlayerInputState(reportedPlayerId, receivedFrame, inputState, movementState);
                 break;
             }
             default:
@@ -454,12 +502,24 @@ file class ServerWorld : World
         }
     }
 
+    public override ulong GetLastProcessedFrame(uint playerId)
+    {
+        ClientInfo player = GetClient(playerId) as ClientInfo;
+        return player.LastProcessedFrame;
+    }
+
+    public override ulong GetLastReceivedFrame(uint playerId)
+    {
+        ClientInfo player = GetClient(playerId) as ClientInfo;
+        return player.LastReceivedFrame;
+    }
+
     public override void UpdatePlayerInputState(uint playerId, ulong frame, PlayerInputState2 inputState, PlayerMovementState movementState)
     {
         base.UpdatePlayerInputState(playerId, frame, inputState, movementState);
 
-        ClientInfo player = GetClient(playerId) as ClientInfo;
+        //ClientInfo player = GetClient(playerId) as ClientInfo;
-        player.LastReceivedFrame = frame; // Dropped frames should be ignored?
+        //player.LastReceivedFrame = frame; // Dropped frames should be ignored?
     }
 
     protected override PlayerActor SpawnPlayer(uint playerId, Float3 position, Vector3 eulerAngles)
@@ -526,7 +586,7 @@ file class ClientWorld : World
             public bool Jump;*/
 
 
-            Console.Print($"client send {Frame}");
+            //Console.Print($"client send {Frame}");
             UpdatePlayerInputState(player.PlayerId, Frame, inputState, movementState);
             //Console.Print($"cframe: {Frame}");
 
@@ -534,12 +594,15 @@ file class ClientWorld : World
             message.WriteByte((byte)GameModeMessageType2.PlayerInput);
             message.WriteUInt64(Frame);
             message.WriteUInt32(player.PlayerId);
+            message.WriteSingle(Time.TimeSinceStartup);
             message.WriteVector2(inputState.ViewDelta);
             message.WriteSingle(inputState.MoveForward);
             message.WriteSingle(inputState.MoveRight);
             message.WriteBoolean(inputState.Attack);
             message.WriteBoolean(inputState.Jump);
             NetworkManager.ClientEndSendMessage(ref message);
+
+            //Console.Print("send: " + Frame.ToString());
         }
         base.OnLateUpdate();
     }
@@ -644,6 +707,18 @@ file class ClientWorld : World
 
     public override bool IsLocalPlayer(uint playerId) => playerId == _localPlayerId;
 
+    public override ulong GetLastProcessedFrame(uint playerId)
+    {
+        //ClientInfo player = GetClient(playerId) as ClientInfo;
+        return 0;
+    }
+
+    public override ulong GetLastReceivedFrame(uint playerId)
+    {
+        //ClientInfo player = GetClient(playerId) as ClientInfo;
+        return 0;
+    }
+
     public void OnClientConnected(NetworkConnection connection)
     {
         uint playerId = connection.ConnectionId;

Source/Game/Player/PlayerInput2.cs

@@ -1,15 +1,17 @@
 using System;
 using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using System.Runtime.InteropServices;
 using System.Text;
+using System.Threading;
 using System.Threading.Tasks;
 using FlaxEngine;
 
 namespace Game;
 
 [StructLayout(LayoutKind.Sequential)]
-public struct PlayerInputState2
+public struct PlayerInputState2 : IEquatable<PlayerInputState2>
 {
     public ulong Frame;
     public Float2 ViewDelta;
@@ -17,6 +19,22 @@ public struct PlayerInputState2
     public float MoveRight;
     public bool Attack;
     public bool Jump;
+
+    /*public override bool Equals([NotNullWhen(true)] object obj)
+    {
+        if (obj is not PlayerInputState2 other)
+            return false;
+        return Frame == other.Frame && ViewDelta == other.ViewDelta && MoveForward == other.MoveForward && MoveRight == other.MoveRight && Attack == other.Attack && Jump == other.Jump;
+    }*/
+
+    public bool Equals(PlayerInputState2 other)
+    {
+        return Frame == other.Frame && ViewDelta == other.ViewDelta && MoveForward == other.MoveForward && MoveRight == other.MoveRight && Attack == other.Attack && Jump == other.Jump;
+    }
+
+    public static bool operator ==(PlayerInputState2 left, PlayerInputState2 right) => left.Equals(right);
+
+    public static bool operator !=(PlayerInputState2 left, PlayerInputState2 right) => !left.Equals(right);
 }
 
 public interface IPlayerInput
@@ -80,6 +98,9 @@ public class PlayerInput2 : IPlayerInput
         _recordState.Attack |= Input.GetAction("Attack");
         _recordState.Jump |= Input.GetAction("Jump");
         _recordState.Frame = _frame;
+
+        if (Input.GetKeyDown(KeyboardKeys.F))
+            Thread.Sleep(20);
     }
 
     public PlayerInputState2 GetState() => _recordState;

Source/Game/Player/PlayerMovement.cs

@@ -74,6 +74,7 @@ public struct PlayerMovementState
     public int numJumps;
     public bool jumped;
     public bool onGround;
+    public ulong frame;
 
 
     public PlayerMovementState()
@@ -250,9 +251,20 @@ public class PlayerMovement : Script
         viewAnglesLastFrame = viewAngles;
     }
 
+    private static int framedropped = 0;
     public override void OnUpdate()
     {
-        Console.Print("playerMovement OnUpdate");
+        if (World.IsServer && Mathf.Abs(Time.DeltaTime - (1.0f / Time.UpdateFPS)) > (1.0f / Time.UpdateFPS) * 0.999f)
+        {
+            Console.Print($"drop: {Time.DeltaTime*1000.0f}ms");
+            framedropped = 3;
+        }
+        else if (World.IsServer && framedropped > 0)
+        {
+            Console.Print("dropping...");
+            framedropped--;
+        }
+        //Console.Print($"{(World.IsClient ? "[cl] " : "[sv] ") + World.Frame.ToString()} playerMovement OnUpdate");
         //input.OnUpdate();
 
 
@@ -315,7 +327,7 @@ public class PlayerMovement : Script
 
     public override void OnFixedUpdate()
     {
-        Console.Print("playerMovement OnFixedUpdate");
+        //Console.Print($"{(World.IsClient ? "[cl] " : "[sv] ") + World.Frame.ToString()} playerMovement OnFixedUpdate");
         float timeDeltaDiff = Time.DeltaTime - 1.0f / Time.PhysicsFPS;
         if (Time.PhysicsFPS > 0 && Math.Abs(timeDeltaDiff) > 0.0001f)
             Console.Print("Time.DeltaTime is not stable: " + timeDeltaDiff);
@@ -413,13 +425,93 @@ public class PlayerMovement : Script
             }
         }
 
-        if (!predict)
+        if (World.IsServer)
+        {
+            ulong currentFrame = World.GetLastProcessedFrame(PlayerId);
+            {
+                // Rewind to last confirmed state
+                var frameInfo = World.GetPlayerFrame(PlayerId, currentFrame);
+                if (frameInfo != null && frameInfo.movementState.frame == currentFrame)
+                {
+                    // Reset all state to latest confirmed state from server
+                    movementState.position = frameInfo.movementState.position;
+                    movementState.currentVelocity = frameInfo.movementState.currentVelocity;
+                    movementState.lastJumped = frameInfo.movementState.lastJumped;
+                    movementState.numJumps = frameInfo.movementState.numJumps;
+                    movementState.jumped = frameInfo.movementState.jumped;
+                    Actor.Position = movementState.position;
+                    SetCameraEulerAngles(frameInfo.movementState.viewAngles, true);
+                    //ApplyInputToCamera(frameInfo.inputState, true);
+                }
+                else if (frameInfo == null)
+                {
+                    // First frame, update the known state
+                    movementState.viewAngles = viewAngles;
+                    World.UpdatePlayerState(PlayerId, currentFrame, movementState);
+                }
+                currentFrame++;
+            }
+
+            //Console.Print("before:" + viewAngles.ToString());
+
+            ulong lastFrame = World.GetLastReceivedFrame(PlayerId);
+            PlayerFrame lastFrameInfo = null;
+            for (; currentFrame < lastFrame+1; currentFrame++)
+            {
+                var frameInfo = World.GetPlayerFrame(PlayerId, currentFrame);
+                if (frameInfo == null || frameInfo.inputState.Frame != currentFrame)
+                //if (!Input.GetState(currentFrame, out var pastInputState, out var pastActorState))
+                {
+                    Console.Print($"frame {currentFrame} missing");
+                    frameInfo = lastFrameInfo; // Use last known input
+
+                    if (frameInfo == null)
+                    {
+                        // FIXME
+                        frameInfo = new PlayerFrame()
+                        {
+                            inputState =
+                            {
+                                Frame = currentFrame,
+                            },
+                            movementState = movementState,
+                        };
+                        frameInfo.movementState.frame = currentFrame;
+                    }
+                    //continue;
+                    //Console.Print($"not predicting");
+                    //predict = false;
+                    //break;
+                }
+                else
+                {
+                    Input.SetFrame(currentFrame);
+                    Input.UpdateState();
+
+                    ApplyInputToCamera(frameInfo.inputState, true);
+                    lastFrameInfo = frameInfo;
+                }
+                SimulatePlayerMovement(frameInfo.inputState, currentFrame);
+                movementState.viewAngles = viewAngles;
+
+                //Console.Print("tick: " + viewAngles.ToString());
+
+                //if (frameInfo.movementState.frame != currentFrame)
+                    World.UpdatePlayerState(PlayerId, currentFrame, movementState);
+                //else
+                //    currentFrame = currentFrame;
+            }
+        }
+        else if (!predict)
         {
             SetCameraEulerAngles(viewAnglesLastFrame, true);
             ApplyInputToCamera(inputState, true);
             SimulatePlayerMovement(inputState, World.Frame); // MAYBE?
         }
 
+        //if (!movementState.currentVelocity.IsZero)
+        //    Console.Print($"{(World.IsClient ? "client" : "server")} {World.Frame} vel: {movementState.currentVelocity}, pos: {movementState.position}");
+
         viewAnglesLastFrame = viewAngles;
 
 #if false