data-driven-gameplay-design

Data-Driven Gameplay Design

Overview

Designers balance games by changing numbers hundreds of times. If a number lives in code, each change is a programmer task, a rebuild and a review. If it lives in a data asset, it is an edit a designer can make and a test can check. The code defines what a sword is; the data says what this sword does.

Core principle: Behaviour in code, tuning in data. Data is typed, validated at load, referenced by a stable ID, and never mutated at runtime.

The data asset per engine

// Unity: ScriptableObject definition
[CreateAssetMenu(menuName = "Game/Weapon")]
public sealed class WeaponDefinition : ScriptableObject {
    [SerializeField] string id;
    [SerializeField, Min(0)] int damage = 10;
    [SerializeField, Min(0.05f)] float cooldownSeconds = 0.5f;
    [SerializeField] AnimationCurve falloff = AnimationCurve.Linear(0, 1, 1, 0);
    public string Id => id; public int Damage => damage; public float CooldownSeconds => cooldownSeconds;
    void OnValidate() { if (string.IsNullOrWhiteSpace(id)) Debug.LogError($"{name}: missing id", this); }
}

# Godot: a Resource saved as .tres
class_name WeaponDefinition extends Resource
@export var id: StringName
@export_range(0, 1000) var damage: int = 10
@export_range(0.05, 10.0, 0.05) var cooldown_seconds: float = 0.5

// Unreal: a primary data asset (or an FTableRowBase row in a DataTable imported from CSV)
UCLASS(BlueprintType)
class UWeaponDefinition : public UPrimaryDataAsset {
    GENERATED_BODY()
public:
    UPROPERTY(EditDefaultsOnly, meta = (ClampMin = "0")) int32 Damage = 10;
    UPROPERTY(EditDefaultsOnly, meta = (ClampMin = "0.05")) float CooldownSeconds = 0.5f;
    virtual FPrimaryAssetId GetPrimaryAssetId() const override { return FPrimaryAssetId("Weapon", GetFName()); }
};

// Web: JSON validated once at load (zod)
export const Weapon = z.object({
  id: z.string().min(1),
  damage: z.number().int().nonnegative(),
  cooldownSeconds: z.number().min(0.05),
});
export const weapons = z.array(Weapon).parse(await (await fetch("data/weapons.json")).json());