This document is about: QUANTUM 3

Migration Guide

The complete guide to migrate Quantum 2.1 projects to Quantum 3.0.

Make sure to upgrade the projects to the latest Quantum 2.1 release and Unity 2021.3 before starting the Quantum 3 migration.

The automated process is recommended to use. When facing problems use the instructions for debugging and contact us.

Scripts GUIDs have been preserved, so prefabs and scenes are not going to suffer from missing components.

To reduce the number of possible compile errors to a minimum during migration, obsoleted scripts with legacy names are provided as well.

The following addons are not yet compatible with Quantum 3:

  • FlowFields
  • Asset Injection

Quantum 3.0 Migration

  • Ensure that the project has a backup and/or is under source control.
  • Upgrade the Quantum project to the latest 2.1 Quantum SDK
  • Upgrade the Quantum project to Unity Editor 2021.3 or later
  • Because of changes to the Quantum Asset
    • Each non-abstract non-generic Asset has to live in a separate file that is names as this: <AssetName>.cs
    • Methods that are common for ScriptableObject have to be renamed: Update(), Start(), etc.
  • If the GraphProfiler addon has been added, and it has been moved from its default location Assets/Photon/Profiling it has to be deleted.
  • Download the latest package
  • Extract the content into the root folder of the Quantum 2.1 project
  • Bot SDK specifics: find on the Bot SDK v3 package the migration instructions which are specific to the addon

A) Automated Process

  • Run the Quantum3Migration.ps1 Powershell script
    • To troubleshoot inspect the migration logs and enable -PauseAfterEachStep then wrap the changes into a git commit after each step.
  • Open Unity Editor
  • Continue with Final Steps
Quantum3Migration.ps1 -UnityEditorPath <path> -Quantum2MigrationPreparationPackagePath <path> -Quantum3PackagePath <path> -Quantum3MigrationPackagePath <path> [..]

  -UnityEditorPath <path>                 The path to the UnityEditor exe.
  -QuantumUnityPath <path>                The path to the Quantum Unity project folder. By default "quantum_unity".
  -QuantumCodePath <path>                 The path to the Quantum code project. By default "quantum_code/quantum.code".
  -AssetDBPath <path>                     The path to the temporary exported assets. By default "Quantum3MigrationAssets".
  -Quantum2MigrationPreparationPackagePath <path> 
                                         The path to the Quantum 3 Migration Preparation unitypackage.
  -Quantum3PackagePath <path>            The path to the Quantum 3 SDK unitypackage.
  -Quantum3MigrationPackagePath <path>   The path to the Quantum 3 Migration unitypackage.
  -LogBasePath <path>                    The folder where the migration logs are stored. If not set logs are created inside the executing directory.
  -AssemblyDefinitionsDecision           Define the answer for the "remove assembly definition" prompt. "yes" or "no".
  -PauseAfterEachStep                    Pause and wait for user input after each step. Default is false.
  -SkipQuantum3PackageImports            Disable the package import steps.
  -SkipQuantumCodeCopy                   Disable importing the quantum code.
  -SkipInitialCodeGen                    Disable initial CodeGen steps.
  -SkipCompileErrorDetection             Disable waiting for compiler error fixes.
  -SkipAssetsUpgrade                     Disable upgrading the Quantum assets.

B) Manual Process

  • Import Quantum3MigrationPreparation.unitypackage
  • Run Quantum > Migration Preparation > Add Migration Defines
  • Run Quantum > Migration Preparation > Export Assets
  • Run Quantum > Migration Preparation > Delete Photon
  • Import Photon-Quantum-3.0.0-Preview.unitypackage (if the Unity Editor crashes, restart Unity)
  • Import Photon-Quantum-3.0.0-Preview-Migration.unitypackage
  • Restart Unity Editor (click Ignore on the Enter Safemode dialog)
  • Run Quantum > Migration > Import Simulation Project
  • Run Quantum > Migration > Run Initial CodeGen
  • Optionally run Quantum > Migration > Run Delete Assembly Definitions
  • Restart Unity Editor (click Ignore on the Enter Safemode dialog)
  • Fix compilation errors
    • If Quantum AssetObjects have existing abstract void Update(Frame f) methods Unity will complain that ScriptableObject have to have parameter-less Update() methods, add void Update() {} to fix the compilation error
  • Run Quantum > Migration > Check Asset Object Scripts
  • Run Quantum > Migration > Transfer AssetBase Guids To AssetObjects
  • Run Quantum > Migration > Upgrade AssetsObjects
  • Run Quantum > Migration > Enable AssetObject Postprocessor
  • Run Quantum > Migration > Reimport All AssetObjects
  • Run the Quantum user file installation from the QuantumHub (Ctrl+H)

Final Steps

  • While the migration define QUANTUM_ENABLE_MIGRATION is enabled, the detection if CodeGen has to run (qtn files changed) is disabled and needs to be run manually using the Unity menu: Quantum > CodeGen > Run Qtn CodeGen
  • Scripts have gone through an extensive refactor:
    • Component prototype suffix has been changed from _Prototype to Prototype.
    • Component prototype wrapper prefix changed from EntityComponent to QPrototype (e.g. EntityComponentTransform2D -> QPrototypeTransform2D).
    • All Unity-only scripts have been put in Quantum namespace and have been given Quantum prefix (e.g. MapData -> QuantumMapData, EntityPrototype -> QuantumEntityPrototype).
  • The config assets may have different names and different locations, browse them inside the Quantum Setup section.
  • QuantumEditorSettings was split into QuantumEditorSettings and QuantumGameGizmosSettings.
  • A new set of default configs (previously located in Resources/DB/Configs) has been generated and does not support static Guids anymore.
  • A Quantum3 AppId has to be created on the Photon dashboard.
  • QuantumEditorSettings.AssetSearchPaths can be set to Assets to search the complete project. It's fast enough now.
  • Let Unity reimport the Quantum assets (right-click > Reimport) located in the Resources folder for example and reimport the QuantumUnityDB.qunitydb asset (which will fix broken Quantum Asset Guids).
  • Re-bake all maps and navmeshes.
  • Quantum 3 API changes have all been wrapped into [Obsolete] attributes to make a successfully migrated project compile. Make sure to check and fix all related warnings after that especially Quantum asset and prototype scripts and prefer their new names to make GameObject.AddComponent<QAssetEntityView> work.

Breaking Changes Realtime 5

  • The namespaces ExitGames.* are obsolete. Use Photon.Client and Photon.Realtime instead.
  • The LoadBalancingClient was renamed to RealtimeClient.
  • The LoadBalancingClient.LoadBalancingPeer was renamed to RealtimeClient.RealtimePeer.
  • Removed LoadBalancingPeer class. Operations are now in the RealtimeClient.
  • The ExitGames.Client.Photon.Hashtable class was renamed to Photon.Client.PhotonHashtable. The client can only send PhotonHashtable now.
  • ConnectToRegionMaster(), ConnectToMasterServer(), ConnectToNameServer() have been removed. Use only ConnectUsingSettings() instead.
  • LoadBalancingClient.CloudRegion is obsolete. Use RealtimeClient.CurrentRegion instead.
  • LoadBalancingClient.AppVersion is obsolete. Set the version via AppSettings and ConnectUsingSetting() instead.
  • AppId setter now throws a NotImplementedException. Set the AppId in the AppSettings and use ConnectUsingSettings() instead.
  • The RaiseEventOptions class was changed to a struct called RaiseEventArgs.
  • EnterRoomParams was renamed to EnterRoomArgs.
  • OpJoinRandomRoomParams was renamed to JoinRandomRoomArgs.
  • RealtimeClient.ConnectionCallbackTargets is now internal. Use AddCallbackTarget() and RemoveCallbackTarget() instead.
  • Enum DebugLevel was renamed to LogLevel. The enum names are now Pascal case.


"Couldn't set project path"

You renamed the Quantum Unity project folder. Set the QuantumUnityPath parameter to the correct path.

Quantum Hub

During migration, it is possible due to user error or other bugs that Quantum Hub does not allow the user to complete the installation process. To remedy this you can try to delete the PhotonServerSettings scriptable object in your project in order to let the Hub regenerate the files.

Failed Importing Package

Your Quantum 3 package file path is wrong. Set the Quantum3PackagePath parameter to the correct path.


Your Quantum 3 Migration package file path is wrong. Set the Quantum3MigrationPackagePath parameter to the correct path.

Unity Editor Path

The Unity Editor path is the path to the editor executable.

On Windows, it is usually located in C:\Program Files\Unity\Hub\Editor\UNITY_VERSION\Editor\Unity.exe.

The powershell script only works on Windows.

Quantum.Code Project

If you have a different quantum code csproj name other than the default, the migration may fail. You will need to set the QuantumCodePath parameter to the correct path.


The Bot SDK must also be migrated in parallel if you are using it in your project.

Bot SDK data is now a singleton, rather than stored globally.

Powershell Arguments

Powershell arguments must be passed with a single '-' and not '--'.

Example: -UnityEditorPath "C:\Program Files\Unity\Hub\Editor\2021.3.0f1\Editor\Unity.exe" Wrong: --UnityEditorPath "C:\Program Files\Unity\Hub\Editor\2021.3.0f1\Editor\Unity.exe"

.Qtn Fields

It is possible to name a field defined in a .qtn file EntityRef. This is supported by codegen, but not by migration. If you are having errors it is recommended to rename these fields before migrating.

Quantum Version

If you are getting undefined errors, ensure you are updated to latest Quantum 2.1 release before attempting a migration.

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