QTN Syntax Highlighting for Photon Quantum

Syntax highlighting support for .qtn files used in Photon Quantum, a high-performance deterministic multiplayer game engine.

About Photon Quantum

Photon Quantum is a deterministic game engine developed by Exit Games, designed specifically for real-time multiplayer games such as competitive shooters, MOBAs, or strategy games. Unlike traditional game engines, Quantum runs game logic in a deterministic simulation, enabling perfect synchronization of game states across clients without the need for client-side prediction or lag compensation.

Key features of Photon Quantum include:

• Deterministic Simulation – No divergence between players
• Rollback Debugging – Time travel for bug tracking
• Built-in Multiplayer – Photon-native networking support
• Simulation on Client & Server – True lockstep behavior

What Are .qtn Files?

.qtn (Quantum Type Notation) files are used to define components, data types, and structures in Photon Quantum projects. These files form the foundation of your ECS (Entity Component System) setup, defining how game entities behave and what data they hold.

A .qtn file typically contains:

• Component definitions
• Primitive and custom data types (int, FP, bool, EntityRef, list, etc.)
• Quantum-specific constructs that get compiled into usable C# code

Example:

component Player {
  int score;
  FP speed;
  EntityRef target;
  list<int> inventory;
  bool isAlive;
}