toucan_ecs

Simple and safe ECS library for Rust.

Provides basic features, such as: - create and destroy entities; - attach, get or remove components from the entity; - use entry of the entity to modify it; - view components of different types; - view components immutably or mutably.

For now library provides nothing for systems (are responsible for logic). You are free to create your own system!

This crate contains no unsafe code.

Examples

Create and destroy entities

```rust use toucan_ecs::Registry;

let mut registry = Registry::new();

let entity = registry.create(); assert!(registry.contains(entity));

registry.destroy(entity); assert!(!registry.contains(entity)); ```

Use entries to simplify access to the entity's data

```rust use toucan_ecs::Registry;

[derive(Copy, Clone)]

struct Name(&'static str);

[derive(Copy, Clone)]

struct ID(u32);

let mut registry = Registry::new();

// Create new entity let entity = { let mut entry = registry.create_entry(); entry.attach((Name("Hello, World"), ID(42))); assert!(entry.attached::<(Name, ID)>()); entry.entity() }; assert!(registry.attached::<(Name, ID)>(entity));

// Or reuse existing ones if let Some(mut entry) = registry.entry(entity) { entry.removeone::(); } assert!(!registry.attachedone::(entity)); ```

View components with ease

```rust use toucan_ecs::{Entity, Registry};

[derive(Debug, Copy, Clone)]

struct Position { x: f32, y: f32, }

[derive(Debug, Copy, Clone)]

struct Mass(f32);

let mut registry = Registry::new();

// Create our entities and their data for i in 0..10 { let f = i as f32; let position = Position{ x: f / 10.0, y: -f / 10.0 }; let entity = registry.createwith((position,)); assert!(registry.attachedone::(entity)); if i % 2 != 0 { let mass = Mass(f); registry.attachone(entity, mass); assert!(registry.attachedone::(entity)); } }

// Get all entities which have Position and CAN have Mass components for (, mut position, mass) in registry.viewmut::<(Entity, &mut Position, Option<&Mass>)>() { position.x += 1.0; println!("position is {:?}, mass is {:?}", *position, mass.as_deref()); } ```