LogoLogo
HomeOnline DashboardAPIDiscordForums
SDK 0.5.2
SDK 0.5.2
  • Welcome
  • Overview
    • What is coherence?
    • How does coherence work?
    • Features and Roadmap
    • Requirements
  • Get Started
    • Install coherence
    • Scene setup
    • Prefab setup
    • Build and run
    • Baking and code generation
    • Create a free account
    • Deploy replication server
    • Share builds
  • Authority and communication
    • How authority works
    • Authority transfer
    • Commands
    • Client messages
    • Server-side and input queues
    • Animations
  • Persistence
    • Overview
    • Configuring persistence
    • Storage
    • Example – A global counter
  • Optimization
    • Overview
    • Simulation frequency
    • Areas of interest
    • World size
    • Level of detail
    • Interpolation
    • Extrapolation
  • Connected entities
    • Overview
    • Entity references
    • Parent-child relationships
  • Simulators
    • Overview
    • Client vs. simulator logic
    • Build and deploy
    • Simulator load balancing
  • Tutorial project
    • Get the Tutorial Project
    • Start Tutorial
      • 1. Transforms
      • 2. Physics
      • 3. Persistence
      • 4. Animation and Variables
      • 5. AI Navigation
      • 6. Network Commands
      • 7. Network Teams (draft)
  • Game Services
    • Game account
    • Key-value store
    • Matchmaking
  • Developer Portal
    • Overview
    • Dashboard
    • Resource Usage
    • Replicator and Simulator Configuration
    • Enabling Game Services
  • API reference
    • Network SDK
      • CoherenceSync
      • MonoBridge
      • LiveQuery
      • Archetype
      • Sample UI
      • Settings Window
      • Custom Bindings
    • Cloud API
      • API tokens and keys
      • Server discovery
      • Game account
      • Key-value store
      • Matchmaking
    • Replication Server
    • Simulation Server
  • Schema reference
    • Overview
    • Specification
    • Field Settings
    • Archetypes and LOD-ing
  • Resources
    • Downloads
    • SDK Update Guide
    • Video Tutorials
    • Glossary
    • CLI Utilities
    • Helper Scripts
    • Troubleshooting
  • Community
    • Discord
  • Additional information
    • Pricing
    • SLA
    • Unreal Engine support
    • WebGL
    • Peer-to-Peer (P2P)
    • Known Issues
    • Changelog
Powered by GitBook
On this page
  • Physics & Persistence
  • General Set Up
  • In This Scene...
  • Build and Try

Was this helpful?

Export as PDF
  1. Tutorial project
  2. Start Tutorial

3. Persistence

Last updated 3 years ago

Was this helpful?

Physics & Persistence

This scene will show you how easy it is to set up Networking in your Unity project and sync GameObject transforms and Physics objects across the network whilst keeping them persistent. As long as the server is running you can disconnect and re-connect, your world will persist.

In this example each client will have it's own player character to move, we will click on the map to make the entity move to that location, simple click to move functionality and right click to spawn local physics based objects that all other player characters can interact with. Each client will only have control of its local entity. You can disconnect and re-connect and the persistent entities will all remain.

General Set Up

In the Hierarchy of the Scene you can see three core Prefabs:

Coherence Entity is the prefab that will change per Scene with different functionality. It has a standard CharacterControllerand Rigidbody as well as an Agent script which will handle movement functionality through the Input Manager in the Core Scene Setup prefab.

Coherence Connection Events handles overall Scene connectivity. Additionally, it removes all Entities with coherenceSync from the Scene to demo disconnection/reconnection via the Interface without refreshing the Scene.

In This Scene...

The Physics Entity Spawner component is a simple script to instantiate a Coherence Entity Physics Persistent prefab with a coherenceSync component that replicates the transform and position. The component also changes the material based on if it is locally simulated or synced over the network.

Coherence Entity Physics Persistent has Entity Lifetime Type set to Persistent. This means it will remain in the world as long as the replication server is running, even if all clients disconnect. It also has Authority Transfer Style set to Stealing which means the entity can be "stolen" and simulated on a client requesting authority.

The Auto Generate Persistance UUID should be checked so that a unique identification string will be used to identify instances of this entity as unique. When the entity is spawned with this checked, it will generate its own UUID.

This is done via the Input Manager in the Core Scene Setup prefab. When the object is left-clicked, it sends the message "Adopt" to the GameObject on the specific Layer Mask "Physics Entities". The component called Coherence Handler on Coherence Entity Physics Persistent handles the Adopt call and requests the authority change via the coherenceSync component.

Coherence Handler is a basic layer for handling Commands and Events, both sending and receiving. You can create your own or reuse and extend this for your project.

Build and Try

You can build this Scene via the Build Settings. Run the local Replication Server through the Window -> coherence -> Settings window and see how it works. You can try running multiple clients rather than just two and see replicating for each.

Core Scene Setup and Coherence Setup are present in all scenes and described in detail on page.

Start Tutorial