NetworkObject

Description

The NetworkObject class enables network synchronization for game objects in multiplayer games. It handles the replication of object position, rotation, scale, animation, and script properties across all clients, ensuring that all players see a consistent game state.

Namespace

Universe.Network

Properties

Property Type Description
targetObject UniObject The object to synchronize (defaults to the object this script is attached to)
isSceneObject bool Whether this is a persistent scene object rather than a dynamically spawned one (default: false)
syncPosition bool Whether to synchronize position (default: true)
syncRotation bool Whether to synchronize rotation (default: true)
syncScale bool Whether to synchronize scale (default: true)
syncAnimation bool Whether to synchronize animation state (default: true)
syncPhysics bool Whether to synchronize physics properties like velocity (default: false)
syncScripts bool Whether to synchronize script properties (default: true)
viewID int Unique identifier for this network object (0 for auto-assignment) (default: 0)

Methods

OnInit 

void OnInit()

Initializes the network object and registers it with the network system.

IsMaster 

bool IsMaster()

Checks if the local player is the master client (room owner).

Returns

  • true if the local player is the master client, false otherwise

IsMine 

bool IsMine()

Checks if the local player owns this network object.

Returns

  • true if the object is owned by the local player, false otherwise

Destroy 

void Destroy()

Destroys the network object across all clients if it’s owned by the local player and not a scene object.

AddSyncScript 

void AddSyncScript(uniscript script)

Adds a script to be synchronized across the network.

Parameters

  • script: The script to synchronize

RemoveSyncScript 

void RemoveSyncScript(uniscript script)

Removes a script from network synchronization.

Parameters

  • script: The script to stop synchronizing

Example Usage 

// Create a player character with network synchronization
NetworkObject playerNetworkObject = new NetworkObject();
playerNetworkObject.targetObject = playerCharacter;
playerNetworkObject.syncPosition = true;
playerNetworkObject.syncRotation = true;
playerNetworkObject.syncAnimation = true;
playerNetworkObject.syncPhysics = false; // Use character controller instead
playerNetworkObject.syncScripts = true;

// Create a simple synchronized pickup item
NetworkObject pickupNetworkObject = new NetworkObject();
pickupNetworkObject.syncPosition = true;
pickupNetworkObject.syncRotation = true;
pickupNetworkObject.syncScale = false; // Scale doesn't change
pickupNetworkObject.syncAnimation = false; // No animations
pickupNetworkObject.syncPhysics = false; // No physics needed
pickupNetworkObject.syncScripts = true; // For pickup state

// Add a script to be synchronized
Interactable pickupInteractable = new Interactable();
pickupNetworkObject.AddSyncScript(pickupInteractable);

// Create a persistent scene object
NetworkObject doorNetworkObject = new NetworkObject();
doorNetworkObject.isSceneObject = true; // Part of the scene, not spawned
doorNetworkObject.syncPosition = false; // Only rotates, doesn't move
doorNetworkObject.syncRotation = true; // Door opening/closing
doorNetworkObject.syncAnimation = false;
doorNetworkObject.syncPhysics = false;
doorNetworkObject.syncScripts = true; // For door state

Technical Details

  • The network object system uses view IDs to identify objects across the network
  • Objects can be owned by a specific player or shared (like scene objects)
  • Only the owner of an object can directly modify its synchronized properties
  • Scene objects persist throughout the game session and are not destroyed on owner disconnect
  • Dynamic objects are created at runtime and typically belong to a specific player
  • Synchronization is selective to minimize network traffic; only enable what’s needed
  • Script synchronization allows custom properties to be replicated across the network

Use Cases

  • Player characters and vehicles
  • Projectiles and weapons
  • Interactive objects like doors, buttons, levers
  • Collectible items and powerups
  • Movable objects and physics props
  • NPCs and enemies in cooperative games
  • Shared world objects that can change state

Notes

  • For optimal network performance, only synchronize what’s necessary
  • Physics synchronization can be bandwidth-intensive; use carefully
  • Animation synchronization works best with simple animation states
  • For complex custom synchronization, implement custom serialization in scripts
  • Scene objects should typically be marked with isSceneObject = true
  • Use different synchronization strategies based on game type (e.g., action games need more frequent position updates)
  • Ownership determines which client can directly modify an object
  • Works with NetworkGame.cs for overall network management
  • Works with ScriptSynchronizer.cs for easier script synchronization
  • Can be used with Interactable.cs for networked interactive objects

Dependencies

  • Uses NetworkUtil for network operations
  • Uses UniObjectUtil to access the target object if not specified