Crate shipyard[−][src]

Expand description

Shipyard is an Entity Component System focused on usability and speed.

Getting started

The user guide is a great place to learn all about Shipyard!
Here’s two examples to get an idea of what it provides:

use shipyard::*;

struct Health(f32);
struct Position {
    _x: f32,
    _y: f32,
}

fn in_acid(positions: View<Position>, mut healths: ViewMut<Health>) {
    for (_, mut health) in (&positions, &mut healths)
        .iter()
        .filter(|(pos, _)| is_in_acid(pos))
    {
        health.0 -= 1.0;
    }
}

fn is_in_acid(_: &Position) -> bool {
    // it's wet season
    true
}

let world = World::new();

world.run(
    |mut entities: EntitiesViewMut,
     mut positions: ViewMut<Position>,
     mut healths: ViewMut<Health>| {
        entities.add_entity(
            (&mut positions, &mut healths),
            (Position { _x: 0.0, _y: 0.0 }, Health(1000.0)),
        );
    },
);

world.run(in_acid);

Let’s make some pigs!

use shipyard::*;

struct Health(f32);
struct Fat(f32);

fn reproduction(
    mut fats: ViewMut<Fat>,
    mut healths: ViewMut<Health>,
    mut entities: EntitiesViewMut,
) {
    let count = (&healths, &fats)
        .iter()
        .filter(|(health, fat)| health.0 > 40.0 && fat.0 > 20.0)
        .count();

    for _ in 0..count {
        entities.add_entity((&mut healths, &mut fats), (Health(100.0), Fat(0.0)));
    }
}

fn meal(mut fats: ViewMut<Fat>) {
    for slice in (&mut fats).iter().into_chunk(8).ok().unwrap() {
        for fat in slice {
            fat.0 += 3.0;
        }
    }
}

fn age(mut healths: ViewMut<Health>, thread_pool: ThreadPoolView) {
    use rayon::prelude::ParallelIterator;

    thread_pool.install(|| {
        (&mut healths).par_iter().for_each(|health| {
            health.0 -= 4.0;
        });
    });
}

let world = World::new();

world.run(
    |mut entities: EntitiesViewMut, mut healths: ViewMut<Health>, mut fats: ViewMut<Fat>| {
        for _ in 0..100 {
            entities.add_entity((&mut healths, &mut fats), (Health(100.0), Fat(0.0)));
        }
    },
);

world
    .add_workload("Life")
    .with_system(system!(meal))
    .with_system(system!(age))
    .build();
world
    .add_workload("Reproduction")
    .with_system(system!(reproduction))
    .build();

for day in 0..100 {
    if day % 6 == 0 {
        world.run_workload("Reproduction");
    }
    world.run_default();
}

world.run(|healths: View<Health>| {
    // we've got some new pigs
    assert_eq!(healths.len(), 900);
});

Features

parallel (default) — adds parallel iterators and dispatch
serde — adds (de)serialization support with serde
non_send — add methods and types required to work with !Send components
non_sync — add methods and types required to work with !Sync components
std (default) — let shipyard use the standard library

This crate uses unsafe both because sometimes there’s no way around it, and for performance gain.
Releases should have all invocation of unsafe explained.
If you find places where a safe alternative is possible without repercussion (small ones are sometimes acceptable) feel free to open an issue or a PR.