YggECS

YggECS is a high-performance Entity Component System (ECS) written in Odin. It implements modern features inspired by Flecs, focusing on speed and simplicity. Some design principles were also used in my TypeScript ECS library bitECS.

The name is derived from Yggdrasil, the sacred tree of Norse mythology which binds the earth, heaven, and hell together.

Features

🔥 Blazingly fast iteration

🧬 Archetypes with cache-friendly component storage

🔍 Powerful querying with a simple, declarative API

🔗 Relational entity modeling

Roadmap

• Observers
• Relation traversal for queries
• Query variables
• Add/removeComponent optimizations

Usage

import ecs "./ecs"

Position :: distinct [2]f32
Velocity :: distinct [2]f32
Health :: distinct int
Contains :: struct { amount: int }
Silver :: distinct struct {}

main :: proc () {
    using ecs
    
    world := create_world()
    defer delete_world(world)

    entity := add_entity(world)
    add_component(world, entity, Position{0, 0})
    add_component(world, entity, Velocity{1, 1})
    add_component(world, entity, Health(100))

    gold := add_entity(world)
    add_component(world, item, pair(Contains{12}, gold))
    add_component(world, item, pair(Contains{58}, Silver))

    for archetype in query(world, has(Position), has(Velocity)) {
        positions := get_table(world, archetype, Position, [2]f32)
        velocities := get_table(world, archetype, Velocity, [2]f32)
        for eid,i in archetype.entities {
            positions[i] += velocities[i]
        }
    }

    entities_with_position_not_health := query(world, has(Position), not(Health))
    entities_containing_gold := query(world, pair(Contains, gold))
}