Behavior Class

Definition

Namespace: Brine2D.ECS

Base class for behaviors — logic that operates on a single entity. Each entity gets its own behavior instance with constructor injection support.

public abstract class Behavior

Inheritance System.Object → Behavior

Remarks

Use behaviors for entity-specific logic (player movement, boss AI, etc.). For batch processing of many entities, use systems instead.

Execution order: During Brine2D.ECS.EntityWorld.Update\(Brine2D\.Core\.GameTime\), all IUpdateSystems run first (sorted by UpdateOrder), then all behaviors (sorted by UpdateOrder). During Brine2D.ECS.EntityWorld.FixedUpdate\(Brine2D\.Core\.GameTime\), all IFixedUpdateSystems run first (sorted by FixedUpdateOrder), then all behaviors (sorted by FixedUpdateOrder). During Brine2D.ECS.EntityWorld.Render\(Brine2D\.Rendering\.IRenderer,Brine2D\.Core\.GameTime\), all IRenderSystems run first (sorted by RenderOrder), then all behaviors (sorted by RenderOrder). Behaviors therefore always execute after system-rendered content. If you need to render between systems, move the render logic into a custom IRenderSystem with the appropriate RenderOrder.

public class PlayerMovementBehavior : Behavior
{
    private readonly IInputContext _input;
    private readonly IAudioService _audio;

    public PlayerMovementBehavior(IInputContext input, IAudioService audio)
    {
        _input = input;
        _audio = audio;
    }

    public override int UpdateOrder => 10;

    public override void Update(GameTime gameTime)
    {
        if (_input.IsKeyDown(Key.W))
            _audio.PlaySound(_footstep);
    }
}