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Multiple transform sync strategy

Discussion in 'Multiplayer' started by guram58chaganava, Mar 12, 2023.

?

Generally, which approach is more effective in terms of performance and bandwidth consumption, creat

  1. One NetworkVariable

    50.0%
  2. Multiple NetworkVariables

    50.0%
  1. guram58chaganava

    guram58chaganava

    Joined:
    Jul 8, 2020
    Posts:
    5
    I am going to sync rotations of different transforms between two players. The total number of transforms to be synced is up to 50. Only those transforms that change must be synced. For the task, it is important to consume as little bandwidth as possible.

    There is no need for the precision of float in the task, so I don't use clientNetworkTransform. Instead, I consider the custom serialization using NetworkVariable in two scenarios which are shown below:

    1) Creating one NetworkVariable containing all of the data to be synced.
    Code (CSharp):
    1. using System;
    2. using Unity.Netcode;
    3. using UnityEngine;
    4.  
    5. public class OneNetworkVariable : NetworkBehaviour
    6. {
    7.     private NetworkVariable<RotationData> rotations;
    8.  
    9.     private void Awake() {
    10.         rotations = new NetworkVariable<RotationData>(writePerm: NetworkVariableWritePermission.Owner);
    11.     }
    12.  
    13.     public override void OnNetworkSpawn()
    14.     {
    15.         // some code
    16.     }
    17.  
    18.     void Update()
    19.     {
    20.         if (IsOwner){
    21.          
    22.             rotations.Value = new RotationData{
    23.            
    24.                 RotationA = objectA.rotation.eulerAngles,
    25.                 RotationB = objectB.rotation.eulerAngles,
    26.                 RotationC = objectC.rotation.eulerAngles,
    27.                 RotationD = objectD.rotation.eulerAngles,
    28.                 /* .. */
    29.             };
    30.          
    31.         }else{
    32.          
    33.             objectA.rotation = Quaternion.Euler(rotations.Value.RotationA);
    34.             objectB.rotation = Quaternion.Euler(rotations.Value.RotationB);
    35.             objectC.rotation = Quaternion.Euler(rotations.Value.RotationC);
    36.             objectD.rotation = Quaternion.Euler(rotations.Value.RotationD);
    37.             /* .. */
    38.         }
    39.     }
    40.  
    41.     private struct RotationData : INetworkSerializable, IEquatable<RotationData> {
    42.      
    43.         private short RotationA_x, RotationA_y, RotationA_z;
    44.         private short RotationB_x, RotationB_y, RotationB_z;
    45.         /* ... */
    46.      
    47.         private short RotationD_y, RotationD_z;
    48.         /* ... */
    49.      
    50.         private short RotationG_z;
    51.         /* ... */
    52.  
    53.      
    54.         internal Vector3 RotationA {
    55.             get => new((float)RotationA_x, (float)RotationA_y, (float)RotationA_z);
    56.             set {
    57.                 RotationA_x = (short)(value.x);
    58.                 RotationA_y = (short)(value.y);
    59.                 RotationA_z = (short)(value.z);
    60.             }
    61.         }
    62.      
    63.         internal Vector3 RotationB {
    64.             get => new((float)RotationB_x, (float)RotationB_y, (float)RotationB_z);
    65.             set {
    66.                 RotationB_x = (short)(value.x);
    67.                 RotationB_y = (short)(value.y);
    68.                 RotationB_z = (short)(value.z);
    69.             }
    70.         }
    71.         /* ... */
    72.      
    73.         internal Vector3 RotationD {
    74.             get => new(0, (float)RotationD_y, (float)RotationD_z);
    75.             set {
    76.                 RotationD_y = (short)(value.y);
    77.                 RotationD_z = (short)(value.z);
    78.             }
    79.         }
    80.         /* ... */
    81.      
    82.         internal Vector3 RotationG {
    83.             get => new(0, 0, (float)RotationG_z);
    84.             set {
    85.                 RotationG_z = (short)(value.z);
    86.             }
    87.         }
    88.         /* ... */
    89.  
    90.         public void NetworkSerialize<T>(BufferSerializer<T> serializer) where T : IReaderWriter {
    91.          
    92.             serializer.SerializeValue(ref RotationA_x);
    93.             serializer.SerializeValue(ref RotationA_y);
    94.             serializer.SerializeValue(ref RotationA_z);
    95.          
    96.             serializer.SerializeValue(ref RotationB_x);
    97.             serializer.SerializeValue(ref RotationB_y);
    98.             serializer.SerializeValue(ref RotationB_z);
    99.             /* ... */
    100.          
    101.             serializer.SerializeValue(ref RotationD_y);
    102.             serializer.SerializeValue(ref RotationD_z);
    103.             /* ... */
    104.          
    105.             serializer.SerializeValue(ref RotationG_z);
    106.             /* ... */
    107.         }
    108.      
    109.         public bool Equals(RotationData other)
    110.         {
    111.             return Mathf.Abs(RotationA_x - other.RotationA_x) < 3
    112.                 && Mathf.Abs(RotationA_y - other.RotationA_y) < 3
    113.                 && Mathf.Abs(RotationA_z - other.RotationA_z) < 3
    114.                 && Mathf.Abs(RotationB_x - other.RotationB_x) < 3
    115.                 && Mathf.Abs(RotationB_y - other.RotationB_y) < 3
    116.                 && Mathf.Abs(RotationB_z - other.RotationB_z) < 3
    117.                 /* ... */
    118.              
    119.                 // according to this function, two structs will be equal
    120.                 // if all of their variables are approximately equal
    121.         }
    122.     }
    123. }
    124.  
    2) Creating multiple NetworkVariables each containing data representing one transform rotation.

    Code (CSharp):
    1. using System;
    2. using Unity.Netcode;
    3. using UnityEngine;
    4.  
    5. public class MultipleNetworkVariables : NetworkBehaviour
    6. {
    7.     private NetworkVariable<Data3> RotationA;
    8.     private NetworkVariable<Data3> RotationB;
    9.     private NetworkVariable<Data3> RotationC;
    10.  
    11.     private NetworkVariable<Data2> RotationD;
    12.     private NetworkVariable<Data2> RotationE;
    13.     private NetworkVariable<Data2> RotationF;
    14.  
    15.     private NetworkVariable<Data1> RotationG;
    16.     private NetworkVariable<Data1> RotationH;
    17.     private NetworkVariable<Data1> RotationI;
    18.  
    19.     /*
    20.         ...
    21.         other NetworkVariables
    22.     */
    23.  
    24.     private void Awake() {
    25.      
    26.         RotationA = new NetworkVariable<Data3>(writePerm: NetworkVariableWritePermission.Owner);
    27.         RotationB = new NetworkVariable<Data3>(writePerm: NetworkVariableWritePermission.Owner);
    28.         RotationC = new NetworkVariable<Data3>(writePerm: NetworkVariableWritePermission.Owner);
    29.      
    30.         RotationD = new NetworkVariable<Data2>(writePerm: NetworkVariableWritePermission.Owner);
    31.         /* ... */
    32.     }
    33.  
    34.     public override void OnNetworkSpawn()
    35.     {
    36.         // some code
    37.     }
    38.  
    39.     void Update()
    40.     {
    41.      
    42.         if (IsOwner){
    43.          
    44.             RotationA.Value = new Data3 {
    45.                 Data = objectA.rotation.eulerAngles
    46.             };
    47.          
    48.             RotationB.Value = new Data3 {
    49.                 Data = objectB.rotation.eulerAngles
    50.             };
    51.          
    52.             RotationC.Value = new Data3 {
    53.                 Data = objectC.rotation.eulerAngles
    54.             };
    55.          
    56.             RotationD.Value = new Data2 {
    57.                 Data = objectD.rotation.eulerAngles
    58.             };
    59.          
    60.             /* .. */
    61.          
    62.         }else{
    63.          
    64.             objectA.rotation = Quaternion.Euler(RotationA.Value.Data);
    65.             objectB.rotation = Quaternion.Euler(RotationB.Value.Data);
    66.             objectC.rotation = Quaternion.Euler(RotationC.Value.Data);
    67.             objectD.rotation = Quaternion.Euler(RotationD.Value.Data);
    68.             /* ... */
    69.         }
    70.     }
    71.  
    72.     private struct Data3 : INetworkSerializable, IEquatable<Data3> {
    73.         private short valX, valY, valZ;
    74.  
    75.         internal Vector3 Data {
    76.             get => new(valX, valY, valZ);
    77.             set {
    78.                 valX = (short)value.x;
    79.                 valY = (short)value.y;
    80.                 valZ = (short)value.z;
    81.             }
    82.         }
    83.  
    84.         public void NetworkSerialize<T>(BufferSerializer<T> serializer) where T : IReaderWriter {
    85.             serializer.SerializeValue(ref valX);
    86.             serializer.SerializeValue(ref valY);
    87.             serializer.SerializeValue(ref valZ);
    88.         }
    89.      
    90.         public bool Equals(Data3 other)
    91.         {
    92.             return Mathf.Abs(valX - other.valX) < 3
    93.                 && Mathf.Abs(valY - other.valY) < 3
    94.                 && Mathf.Abs(valZ - other.valZ) < 3;
    95.         }
    96.     }
    97.  
    98.     private struct Data2 : INetworkSerializable, IEquatable<Data2> {
    99.         private short valY, valZ;
    100.         //private short _rotY;
    101.  
    102.         internal Vector3 Data {
    103.             get => new(0, valY, valZ);
    104.             set {
    105.                 valY = (short)value.y;
    106.                 valZ = (short)value.z;
    107.             }
    108.         }
    109.  
    110.         public void NetworkSerialize<T>(BufferSerializer<T> serializer) where T : IReaderWriter {
    111.             serializer.SerializeValue(ref valY);
    112.             serializer.SerializeValue(ref valZ);
    113.         }
    114.      
    115.         public bool Equals(Data2 other)
    116.         {
    117.             return Mathf.Abs(valY - other.valY) < 3 && Mathf.Abs(valZ - other.valZ) < 3;
    118.         }
    119.     }
    120.  
    121.     private struct Data1 : INetworkSerializable, IEquatable<Data1> {
    122.         private short valZ;
    123.  
    124.         internal Vector3 Data {
    125.             get => new(0, 0, valZ);
    126.             set {
    127.                 valZ = (short)value.z;
    128.             }
    129.         }
    130.  
    131.         public void NetworkSerialize<T>(BufferSerializer<T> serializer) where T : IReaderWriter {
    132.             serializer.SerializeValue(ref valZ);
    133.         }
    134.      
    135.         public bool Equals(Data1 other)
    136.         {
    137.             return Mathf.Abs(valZ - other.valZ) < 3;
    138.         }
    139.     }
    140.  
    141. }
    To my mind, the approach of multiple NetworkVariables will consume more bandwidth as it implies sending many packets and will contain many headers. Is my opinion correct?

    I think that creating multiple NetworkVariables will allow syncing only those transforms that change. In the case of the first approach, NetworkVariable named 'rotations will be synced even if one of the rotation angles changes. It is because the Equals function will return false if one of the angles changes was greater than 3 degrees. Is there any other way of implementing one NetworkVariable so that it syncs only the data that changes?

    Thank you in advance!