Physics + Netcode not syncing right or something

I am attempting to go from the netcode sample NetCube, some changes here and there, and now I can't move my character anymore
It stopped working when I added physics body to the character, I've already "Update Component List + Generate Code" in the prefab.

Code (CSharp):

1. using Unity.Burst;
2. using Unity.Entities;
3. using Unity.NetCode;
4. using Unity.Networking.Transport;
5. using Unity.Physics;
6. using UnityEngine;
7.  
8. public struct PlayerInput : ICommandData<PlayerInput> {
9.     public uint Tick => tick;
10.     public uint tick;
11.     public int horizontal;
12.     public int vertical;
13.  
14.     public void Deserialize(uint tick, DataStreamReader reader, ref DataStreamReader.Context ctx) {
15.         this.tick = tick;
16.         horizontal = reader.ReadInt(ref ctx);
17.         vertical = reader.ReadInt(ref ctx);
18.     }
19.  
20.     public void Serialize(DataStreamWriter writer) {
21.         writer.Write(horizontal);
22.         writer.Write(vertical);
23.     }
24.  
25.     public void Deserialize(uint tick, DataStreamReader reader, ref DataStreamReader.Context ctx, PlayerInput baseline,
26.         NetworkCompressionModel compressionModel) {
27.         Deserialize(tick, reader, ref ctx);
28.     }
29.  
30.     public void Serialize(DataStreamWriter writer, PlayerInput baseline, NetworkCompressionModel compressionModel) {
31.         Serialize(writer);
32.     }
33. }
34.  
35. public class PlayerSendCommandSystem : CommandSendSystem<PlayerInput> { }
36. public class PlayerReceiveCommandSystem : CommandReceiveSystem<PlayerInput> { }
37.  
38. [UpdateInGroup(typeof(ClientSimulationSystemGroup))]
39. public class SamplePlayerInput : ComponentSystem {
40.     protected override void OnCreate() {
41.         RequireSingletonForUpdate<NetworkIdComponent>();
42.         RequireSingletonForUpdate<EnableDOTSMMOGhostReceiveSystemComponent>();
43.     }
44.  
45.     protected override void OnUpdate() {
46.         var localInput = GetSingleton<CommandTargetComponent>().targetEntity;
47.         if (localInput == Entity.Null) {
48.             var localPlayerId = GetSingleton<NetworkIdComponent>().Value;
49.             Entities.WithNone<PlayerInput>().ForEach((Entity ent, ref PlayerIDComponent player) => {
50.                 if (player.PlayerId == localPlayerId) {
51.                     PostUpdateCommands.AddBuffer<PlayerInput>(ent);
52.                     PostUpdateCommands.SetComponent(GetSingletonEntity<CommandTargetComponent>(), new CommandTargetComponent { targetEntity = ent });
53.                 }
54.             });
55.             return;
56.         }
57.         var input = default(PlayerInput);
58.         input.tick = World.GetExistingSystem<ClientSimulationSystemGroup>().ServerTick;
59.         if (Input.GetKey("a"))
60.             input.horizontal -= 1;
61.         if (Input.GetKey("d"))
62.             input.horizontal += 1;
63.         if (Input.GetKey("s"))
64.             input.vertical -= 1;
65.         if (Input.GetKey("w"))
66.             input.vertical += 1;
67.         var inputBuffer = EntityManager.GetBuffer<PlayerInput>(localInput);
68.         inputBuffer.AddCommandData(input);
69.     }
70. }
71.  
72. [BurstCompile]
73. [UpdateInGroup(typeof(GhostPredictionSystemGroup))]
74. public class MovePlayerSystem : JobComponentSystem {
75.     protected override Unity.Jobs.JobHandle OnUpdate(Unity.Jobs.JobHandle handle) {
76.         handle.Complete();
77.         var group = World.GetExistingSystem<GhostPredictionSystemGroup>();
78.         var tick = group.PredictingTick;
79.         var deltaTime = Time.DeltaTime;
80.         Entities.ForEach((DynamicBuffer<PlayerInput> inputBuffer, ref PhysicsVelocity vel, ref PlayerAcceleration acc, ref PlayerMaxSpeed speed, ref PredictedGhostComponent prediction) => {
81.             if (!GhostPredictionSystemGroup.ShouldPredict(tick, prediction)) {
82.                 Debug.Log(World.Name + " did not predict");
83.                 return;
84.             }
85.             PlayerInput input;
86.             inputBuffer.GetDataAtTick(tick, out input);
87.             if (input.horizontal > 0)
88.                 vel.Linear.x = Mathf.Clamp(vel.Linear.x + deltaTime * acc.Acceleration, -speed.MaxSpeed, speed.MaxSpeed);
89.             else if (input.horizontal < 0)
90.                 vel.Linear.x = Mathf.Clamp(vel.Linear.x - deltaTime * acc.Acceleration, -speed.MaxSpeed, speed.MaxSpeed);
91.             if (input.vertical > 0)
92.                 vel.Linear.z = Mathf.Clamp(vel.Linear.z + deltaTime * acc.Acceleration, -speed.MaxSpeed, speed.MaxSpeed);
93.             else if (input.vertical < 0)
94.                 vel.Linear.z = Mathf.Clamp(vel.Linear.z - deltaTime * acc.Acceleration, -speed.MaxSpeed, speed.MaxSpeed);
95.             Debug.Log(World.Name + " did predict: " + input.horizontal + ", " + input.vertical + vel.Linear);
96.         }).WithoutBurst().Run();// (handle);
97.         return default;
98.     }
99. }
100.  

Last 8 lines of the console, for some reason the console shows 4 servers then 4 clients then repeats rather than 1 client 1 server repeat

Code (CSharp):

1. ServerWorld did predict: 1, 1float3(0.1666656f, -1.8441E-06f, 0.1666667f)
2. ServerWorld did predict: 1, 1float3(0.1666675f, -1.68932E-06f, 0.1666666f)
3. ServerWorld did predict: 1, 1float3(0.1666656f, -1.842527E-06f, 0.1666667f)
4. ServerWorld did predict: 1, 1float3(0.1666675f, 2.041573E-06f, 0.1666666f)
5. ClientWorld0 did predict: 1, 1float3(5f, 1.57506f, 5f)
6. ClientWorld0 did predict: 1, 1float3(5f, 1.57506f, 5f)
7. ClientWorld0 did predict: 1, 1float3(5f, 1.57506f, 5f)
8. ClientWorld0 did predict: 1, 1float3(5f, 1.57506f, 5f)

The Project: https://www.mediafire.com/file/7ll2s2dz12nvf9s/Untituled_DOTS_MMO.zip/file

 

Same here. How to move rigidbodies with netcode?

 

Make sure that the physics body and collider components are enabled, they're disabled in the sample project.
I quickly tested it using the following code and it works as expected.

Code (CSharp):

1. [UpdateInGroup(typeof(GhostPredictionSystemGroup))]
2. public class MoveCubeSystem : ComponentSystem
3. {
4.     protected override void OnUpdate()
5.     {
6.         var group = World.GetExistingSystem<GhostPredictionSystemGroup>();
7.         var tick = group.PredictingTick;
8.         var deltaTime = Time.DeltaTime;
9.         Entities.ForEach((DynamicBuffer<CubeInput> inputBuffer, ref PhysicsVelocity vel, ref PredictedGhostComponent prediction) =>
10.         {
11.             if (!GhostPredictionSystemGroup.ShouldPredict(tick, prediction))
12.                 return;
13.             CubeInput input;
14.             inputBuffer.GetDataAtTick(tick, out input);
15.             vel.Linear.x = input.horizontal;
16.             vel.Linear.z = input.vertical;
17.         });
18.     }
19. }

 

It works in sample project. But if I copy NetCube code to my empty project (or write from scratch), the cube does't move, until I remove Physics Body. Am I miss something?

 

It turned out that you need an extra system to manually update the translation.
The system was hidden in the Asteroids sample.

Code (CSharp):

1. using Unity.Entities;
2. using Unity.Jobs;
3. using Unity.NetCode;
4. using Unity.Transforms;
5.  
6. namespace Asteroids.Server
7. {
8.     [UpdateInGroup(typeof(ServerSimulationSystemGroup))]
9.     [UpdateBefore(typeof(GhostSimulationSystemGroup))]
10.     public class UpdateConnectionPositionSystem : JobComponentSystem
11.     {
12.         protected override JobHandle OnUpdate(JobHandle inputDeps)
13.         {
14.             var translationFromEntity = GetComponentDataFromEntity<Translation>(true);
15.             return Entities.WithNativeDisableContainerSafetyRestriction(translationFromEntity).ForEach(
16.                 (ref GhostConnectionPosition conPos, in CommandTargetComponent target) =>
17.                 {
18.                     if (!translationFromEntity.Exists(target.targetEntity))
19.                         return;
20.                     conPos = new GhostConnectionPosition
21.                     {
22.                         Position = translationFromEntity[target.targetEntity].Value
23.                     };
24.                 }).Schedule(inputDeps);
25.         }
26.     }
27. }

Logically you would need to update the rotation too if necessary.

 

Strangely it was the only system I had to keep to make it work, anyway thanks for clearing that up.

 

So should we still run the move system in the GhostPredictionSystemGroup then, even if it's not really predicted due to using server-side physics?

What about other systems that affect the physics velocity, like wind or any kind of force that should be applied after the move system. In which system group are they supposed to run?

 

Does it mean this feature will come in future or should we not expect something like this?
E.g. running the RaycastCar Demo with netcode and of course client prediction?
There, for the car we do a lot of physic changes, apply impulses etc., if I try to apply an impulse right now to a ghost with prediction with 1sec delay, it will behave very strange.

 

Is the plan to fully support physics prediction and rollback on the client?

Meaning to be able to have a fully physics-based environment (with joints, collisions etc.) which would work with netcode?

(if so that would be fantastic news)

 

The "Predicted client and interpolated client" checkboxes are not removed.
For no 1 component, they are simply not removed.
What should I do about it?

Unity 2021.1.0f1.
NetCode 0.6.

Obviously, you won't be releasing a fixed version because of this.
But can you throw off the corrected script so that I can replace it in the package?
Please! Just checkboxes.

 

I think this is probably the case. In Netcode 0.3 and higher, the Ghost Component Inspector only shows how ghosts are organized in code, so you can't change that checkbox manually.

I needed to set `[GhostComponent (PrefabType = GhostPrefabType.Server)]` in PhysicsMass, PhysicsVelocity, and PhysicsDamping to get physics working in Netcode. As a result, it looks like the image.

However, this method directly rewrites the source code of Unity Physics, and I would like you to support this setting by default if possible. Is it possible?

 

I overlooked that. Thank you. I think that will solve it.

 

Does Netcode support physics in prediction now?

 

Yes