I am in the very early stages of developing a turn-based strategy game with online multiplayer using Unity, C#, and the networking library Photon Fusion. The game itself is based on a board game my brother and I came up with years ago, which was played using a mixture of materials from Risk, Monopoly, and a few other miscellaneous games.

Most of my time so far has been spent building the infrastructure to make online multiplayer possible. The most powerful features of Photon Fusion are designed for real-time applications with small, relatively simple state and thus aren't applicable to my particular use case. However, Fusion provides session hosting/joining, the Photon Cloud for testing, and the ability to define RPCs, all of which have been very useful.

To abstract the complexity of online multiplayer away from the rest of the game logic, I built a state management system using Fusion RPCs that ensures game state updates are properly replicated across the server and all clients and every client request is properly validated. The system requires that each state update (moving a unit, for example) has three components: the data associated with the update, a function that applies the update to the local game state, and a function that determines whether or not the update is allowed at that time. Using this interface, the rest of the game can be developed almost as if it is a pass-and-play game running on a single machine.

I wrote a library that handles the hex coordinate system the map uses, supporting path planning, distance calculations, standard operators, and conversions between different hexagonal coordinate systems. Hexagonal Grids was an immensely helpful resource for understanding the necessary underlying math. I also created an algorithm allowing me to procedurally generate a game map consisting of roughly equally distributed continents. It has many tunable parameters that can be used to adjust the map size, number of continents, continent size, distance between continents, smoothness of continent borders, and water generation.

The final major piece of infrastructure I need to build before diving in to implementing the actual game logic is the UI system. Strategy games such as this one (think the Civilization series) are extremely UI-heavy, so creating elegant abstractions and decoupling the UI as much as possible from the rest of the game will be critical to having a smooth development process down the line.