What is a Building?

Building Entity

Buildings are spawned as an Entity() using the BuildingFactory that creates a new entity and adds necessary components to it. See Entity Component System for how this component system works.

Why use a factory? The game engine already uses the Abstract Factory Pattern, a great way of creating similar objects without specifying a concrete class, so it made sense to conform. he

Spawning and Adding Components in the BuildingFactory

1. A base building is created first by calling createBaseBuilding() which returns an entity with a PhysicsComponent and ColliderCompenet.

This is where to put non unique components (components that every building will possess)

2. The specific components are then added for that specific building

e.g. the TextureRenderComponent which requires the path of the image asset to be constructed which differs for different buildings

3. Some of these components are also configured using a configuration file

e.g. townHall.addComponent(new CombatStatsComponent(config.health, config.baseAttack));

Building configs

The rationale for using configs - Configuring Entities

The current Config Classes extend from the BaseEntityConfig and adds support for a building level up system. Visualisation of the BuildingFactory using BuildingConfigs in a class diagram:

The Building factory loads the configs and uses the fields in them to create and add components to the newly created building entity. private static final BuildingConfigs configs = FileLoader.readClass(BuildingConfigs.class, "configs/buildings.json");