Crate zcomponents

ZComponents - a stupid component storage

I find "serious" ECS to be an overkill for turn-based game logic, so I've created this simple library that does only one thing: stores your components.

Example:

#[macro_use]
extern crate zcomponents;

#[derive(PartialEq, Eq, Clone, Copy, Debug, Hash, Default)]
pub struct Id(i32);

#[derive(Clone, Debug)]
pub struct A {
    value: i32,
}

#[derive(Clone, Debug)]
pub struct B {
    value: i32,
}

#[derive(Clone, Debug)]
pub struct C;

zcomponents_storage!(Storage<Id>: {
    a: A,
    b: B,
    c: C,
});

fn main() {
    // Create a new storage instance.
    let mut storage = Storage::new();

    // It doesn't store anything yet.
    assert_eq!(storage.ids().count(), 0);

    // Allocate a new id.
    let id0 = storage.alloc_id();
    assert_eq!(storage.ids().count(), 1);

    // This Entity doesn't have any components assigned.
    assert!(!storage.is_exist(id0));

    storage.a.insert(id0, A { value: 0 });

    // Now it has a component.
    assert!(storage.is_exist(id0));

    // Allocate another id.
    let id1 = storage.alloc_id();
    assert_eq!(storage.ids().count(), 2);

    storage.a.insert(id1, A { value: 1 });
    storage.b.insert(id1, B { value: 1 });

    // Iterate over everything.
    for id in storage.ids_collected() {
        // We are not sure that this entity has the component,
        // so we must use `get_opt`/`get_opt_mut` methods.
        if let Some(a) = storage.a.get_opt_mut(id) {
            a.value += 1;
        }
        if let Some(b) = storage.b.get_opt_mut(id) {
            b.value += 1;
            storage.c.insert(id, C);
        }
    }

    // Iterate over `a` components.
    for id in storage.a.ids_collected() {
        // Since we are sure that component exists,
        // we can just use `get`/`get_mut` version:
        storage.a.get_mut(id).value += 1;
    }

    // Remove the component
    storage.a.remove(id0);

    // Remove the whole entity
    storage.remove(id0);

    assert!(!storage.is_exist(id0));
}

Macros

zcomponents_storage

Structs

ComponentContainer
IdIter