stupid_simple_collision_detection.rs

pub struct CollisionSystem;

impl<'a> System<'a> for CollisionSystem {
    type SystemData = (
        Entities<'a>,
        WriteStorage<'a, Position>,
        ReadStorage<'a, Velocity>,
        WriteStorage<'a, Collision>,
    );

    fn run(&mut self, data: Self::SystemData) {
        let (entities, mut positions, velocities, mut collisions) = data;

        for (e1, p1, v1, c1) in (&entities, &mut positions, &velocities, &mut collisions).join() {
            for (e2, p2, v2, c2) in (&entities, &mut positions, &velocities, &mut collisions).join() {
                if e1 == e2 {
                    continue;
                }

                // do collision detection and response
            }
        }
    }
}

// Components

#[derive(Debug, Component)]
#[storage(VecStorage)]
pub struct Position(pub Point2);

#[derive(Debug, Component)]
#[storage(VecStorage)]
pub struct Velocity(pub Vector2);

#[derive(Debug, Component)]
#[storage(VecStorage)]
pub struct Collision {
    pub hitboxes: Vec<Hitbox>,
}

#[derive(Debug)]
pub struct Hitbox {
    pub size: Size,
    pub relative_position: Vector2,
}

#[derive(Debug, Default, Copy, Clone)]
pub struct Size {
    pub height: f32,
    pub width: f32,
}