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use std::fmt::Display;
use ecs::event::{Event, Id as EventId};
use ecs::{Component, Query, World};
#[derive(Component)]
struct Health
{
health: u32,
}
#[derive(Component)]
enum AttackStrength
{
Strong,
Weak,
}
#[derive(Component)]
struct EnemyName
{
name: String,
}
impl Display for EnemyName
{
fn fmt(&self, formatter: &mut std::fmt::Formatter<'_>) -> std::fmt::Result
{
self.name.fmt(formatter)
}
}
fn do_attacks(
attacker_query: Query<(AttackStrength,)>,
enemy_query: Query<(Health, EnemyName)>,
)
{
for (attack_strength,) in &attacker_query {
for (mut health, enemy_name) in &enemy_query {
let damage = match *attack_strength {
AttackStrength::Strong => 20,
AttackStrength::Weak => 10,
};
if health.health <= damage {
println!("Enemy '{}' died", *enemy_name);
health.health = 0;
continue;
}
health.health -= damage;
println!("Enemy '{}' took {damage} damage", *enemy_name);
}
}
}
#[derive(Debug, PartialEq, Eq, Hash)]
struct Start;
impl Event for Start
{
fn id(&self) -> EventId
{
EventId::of::<Self>()
}
}
fn main()
{
let mut world = World::new();
world.register_system(&Start, do_attacks);
world.create_entity((
Health { health: 100 },
EnemyName { name: "Big spider".to_string() },
));
world.create_entity((
Health { health: 30 },
EnemyName { name: "Small goblin".to_string() },
));
world.create_entity((
Health { health: 30 },
EnemyName { name: "Headcrab".to_string() },
));
world.create_entity((AttackStrength::Strong,));
world.create_entity((AttackStrength::Weak,));
world.emit(&Start);
}
|
