space-crush/space-crush-common/src/systems/ship_movement.rs

#![allow(dead_code)]

use specs::{prelude::*, ParJoin, Read, ReadStorage, System, WriteStorage};

use crate::{
    components::{Player, PlayerOwned, Position, Ship},
    resources::Global,
    return_if_none,
};

#[derive(Default)]
pub struct ShipMovement;

#[derive(SystemData)]
pub struct ShipMovementData<'a> {
    positions: WriteStorage<'a, Position>,
    ships: ReadStorage<'a, Ship>,
    player_owned: ReadStorage<'a, PlayerOwned>,
    players: ReadStorage<'a, Player>,
    global: Read<'a, Global>,
}

impl<'a> System<'a> for ShipMovement {
    type SystemData = ShipMovementData<'a>;

    fn run(&mut self, data: Self::SystemData) {
        let ShipMovementData {
            mut positions,
            ships,
            player_owned,
            players,
            global,
        } = data;

        (&mut positions, &player_owned, &ships).par_join().for_each(
            |(position, player_owned, ship)| {
                let delta = global.delta * global.world_speed;
                let position = position.get_mut();
                let type_ = ship.type_();
                let player_id = player_owned.owner();
                let player = return_if_none!(players.get(player_id));
                let ship_data = player.ship_data(type_);

                *position += ship.dir() * ship_data.speed * delta;
            },
        );
    }
}