Our first Feature

Features are what makes your game, well, your game. They built on top of plugins to create gameplay!

If you are creating a farming game, you might have a Farming, SeedTrader, and CrossBreeding feature. These features in their turn make use of the Currency, Shop, and Crafting plugins!

We have a Plant content type

class Plant {
  id: PlantId;
  growthTime: number;

  // Whatever it costs to plant (e.g. seeds, money)
  plantCost?: Input[];

  // Requirements to plant (e.g. farming level, upgrade bought)
  plantCondition?: Condition[];

  // Whatever is gained when harvest (e.g. currencies, experience)
  harvestReward?: Output[];
}

An minimal feature could look like this: Planting a seed and harvesting it a few moments later.

class Farming extends LudiekFeature {
  public readonly name: string = 'farming';

  // The state of our feature is automatically persisted by Ludiek
  protected _state = {
    plantId: null,
    timeLeft: 0,
  };

  // Called every game tick
  public update(delta: number) {
    this._state.timeLeft -= delta;
  }

  // Attempt to plant a seed and pay the costs
  public sow(id: PlantId): void {
    if (this._state.plantId !== null) {
      return;
    }

    const plant = getPlant(id);

    if (!this._engine.evaluate(plant.plantCondition)) {
      return;
    }

    if (!this._engine.tryConsume(plant.plantCost)) {
      return;
    }

    this._state.plantId = id;
    this._state.timeLeft = plant.growthTime;
  }

  // Harvest a fully grown plant and reap the rewards
  public reap(): void {
    if (this._state.timeLeft > 0) {
      return;
    }

    const plant = getPlant(this._state.plantId);

    this._engine.produce(plant.harvestReward);
    this._state.plantId = null;
  }
}

Data-driven

As you can see, our feature is still relatively generic. We check a plants “conditions”, pay its “cost” and gain its “reward”.

Because of this approach, we can configure the game through our static content. You can imagine the following 2 plants leading to different gameplay!

# Classical farming game
id: /plant/sunflower
growthTime: 4

plantCost:
  - type: /input/currency
    currency: /currency/seed/sunflower
    amount: 1

harvestReward:
  - type: /output/currency
    currency: /currency/flower/sunflower
    amount: 2

# RPG-like game
id: /plant/sunflower
growthTime: 4

plantCondition:
  - type: /condition/skill-level
    skill: /skill/farming
    level: 5

harvestReward:
  - type: /output/experience
    skill: /skill/farming
    experience: 10

And that is the true power of Ludiek!