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use ecs::actions::Actions;
use ecs::extension::{Collector as ExtensionCollector, Extension};
use ecs::phase::UPDATE as UPDATE_PHASE;
use ecs::{Component, Query, World};
#[derive(Debug, Component)]
struct Position
{
x: u32,
y: u32,
}
#[derive(Debug, Component)]
struct EnemySpawnSource;
#[derive(Debug, Component)]
enum EvilnessLevel
{
Medium,
}
fn spawn_enemies(
spawner_query: Query<(EnemySpawnSource, Position)>,
enemies_query: Query<(EvilnessLevel,)>,
mut actions: Actions,
)
{
let Some((_, enemy_spawner_position)) = spawner_query.iter().next() else {
return;
};
let enemy_cnt = enemies_query.iter().count();
if enemy_cnt > 3 {
return;
}
actions.spawn((
EvilnessLevel::Medium,
Position {
x: enemy_spawner_position.x * enemy_cnt as u32,
y: enemy_spawner_position.y,
},
));
println!("Spawned enemy with medium evilness and 45 strength");
}
struct EnemySpawningExtension;
impl Extension for EnemySpawningExtension
{
fn collect(self, mut collector: ExtensionCollector<'_>)
{
collector.add_system(*UPDATE_PHASE, spawn_enemies);
collector.add_entity((Position { x: 187, y: 30 }, EnemySpawnSource));
}
}
fn main()
{
let mut world = World::new();
world.add_extension(EnemySpawningExtension);
for _ in 0..7 {
world.step();
}
}
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