Deterministic lightweight ECS framework
$ dotnet add package JuDelCo.Lib.CoreECSJuCore ECS is a deterministic lightweight ECS framework.
It's heavily inspired in Entitas, but with some differences:
Any feedback is welcome !
/Packages/manifest.json file in your project folder by adding: "com.judelco.core.ecs": "https://github.com/JuDelCo/CoreECS.git#v1.14.0",
dotnet add package JuDelCo.Lib.CoreECS
Note: All components should be structs for best performance and memory efficiency.
public struct Speed : IComponent
{
public float value;
public Speed(float value) // Optional, syntactic sugar for later
{
this.value = value;
}
}
// IMPORTANT: You need to pass the count of component types you will use to the context
const int COMPONENT_TYPES_COUNT = 9;
var context = new Context(Constants.COMPONENT_TYPES_COUNT);
var entity = context.CreateEntity();
entity.Add(new Speed(2f));
entity.Add(new Position(3, 7));
entity.Replace(new Health(10));
entity.Remove<Speed>();
var hasSpeed = entity.Has<Speed>();
var healthData = entity.Get<Health>();
// You can also chain methods!
context.CreateEntity()
.Add(new Speed(2f))
.Add(new Position(3, 7))
.Replace(new Health(10)) // Note: Replace will add the component if doesn't have it yet
.Remove<Speed>();
// Returns a group containing always all entities with Position and Speed components.
var group = context.GetGroup(MatcherGenerator.AllOf<Position, Speed>());
var entities = group.GetEntities();
foreach (var e in entities)
{
// ...
}// You can also use IInitializeSystem, ICleanupSystem and ITearDownSystem systems
public class MovementSystem : IExecuteSystem
{
private IGroup group;
public MovementSystem(IContext context)
{
// You can also use a shorthand for AllOf components!
// This is equivalent to: GetGroup(MatcherGenerator.AllOf<Position, Speed>())
group = context.GetGroup<Position, Speed>();
}
public void Execute()
{
foreach (var e in group.GetEntities())
{
var position = e.Get<Position>();
var speed = e.Get<Speed>().value;
position.x += speed;
e.Replace(position);
}
}
}public class RenderPositionSystem : ReactiveSystem
{
private IContext context;
private IGroup group;
public RenderPositionSystem(IContext context) : base(context)
{
this.context = context;
}
protected override ICollector GetTrigger(IContext context)
{
return context.GetGroup<Position, View>().CreateCollector(GroupEvent.Added);
}
protected override bool Filter(IEntity entity)
{
// Yes, you can use multiple types in Has<T> method !
return entity.Has<Position, View>();
}
protected override void Execute(List<IEntity> entities)
{
foreach (var e in entities)
{
var position = e.Get<Position>();
e.Get<View>().gameObject.transform.position = new Vector3(position.x, position.y, position.z);
}
}
}Copyright © 2019-2025 Juan Delgado (@JuDelCo)
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
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