My code

Game structure

The application starts in the Menu scene. From there, the player can go to the Settings scene, where they can adjust the sound and music volume or reset their progress. They can also go back to the menu. From the menu, the player can also go to the Level select scene, where they can return to the menu or select a level to play. When a level is selected, the Game scene is loaded and a scene that contains the selected level is loaded additively. This is where the actual gameplay happens. There are basically only two states - playing and paused. The player can pause the game using the pause button, and from there they can restart the level, return to level select, or resume the game.

Game loop

Every update, the game reacts to player inputs and updates the visuals.  

The raw player inputs are preprocessed using ClickPreprocessor and then they are processed by CameraControls and GameControls. GameControls calls functions in GameCommands to issue the commands. AI scripts evaluate what to do and also issue commands using GameCommands functions. The player's current selection or issued commands are visualized by CommandVisuals.

Each node's state is visualized by NodeView and the UI is updated by GameUI.

Nodes exist as monobehaviours that also create their ECS equivalent  entity when the level starts. The Node monobehaviour used mainly as an interface with the game controls and other systems and visuals, whereas the entity participates in the simulation. Units exist only as ECS entities.

The game simulation is handled using ECS systems that execute 20 times per second. UnitMotionSystem makes units move towards their target. DamageableCollisionSystem detects collisions and decreases health or increases upgrade progress appropriately. UnitHealthSystem then kills units that have 0 health. BaseNodeSystem handles node regeneration, upgrades, and what happens when a node is captured. GeneratorNodeSystem and KillerNodeSystem handle behavior specific to these node types. Each node also has a UnitSensingSystem that counts the number of allied and rival units near the node and it commands idle allied units to target the eventual nearby rivals. 

Key scripts

UnitMotionSystem, DamageableCollisionSystem, BaseNodeSystem. Explained above.

Most interesting script

AI

Ugliest script

NodeBehaviorParameters