Extract systems

src/game/mod.rs

@@ -1 +1,4 @@
 pub mod objects;
+pub mod runtime;
+pub mod seed;
+pub mod setup;

src/game/runtime.rs

@@ -0,0 +1,40 @@
+use avian2d::prelude::*;
+use bevy::prelude::*;
+
+use super::objects::Player;
+
+pub fn move_player(
+    time: Res<Time>,
+    keyboard_input: Res<ButtonInput<KeyCode>>,
+    mut velocity: Single<&mut LinearVelocity, With<Player>>,
+) -> Result {
+    let acceleration = 500.0;
+
+    let delta_time = time.delta_secs();
+
+    if keyboard_input.any_pressed([KeyCode::KeyW, KeyCode::ArrowUp]) {
+        velocity.y += acceleration * delta_time;
+    }
+    if keyboard_input.any_pressed([KeyCode::KeyS, KeyCode::ArrowDown]) {
+        velocity.y -= acceleration * delta_time;
+    }
+    if keyboard_input.any_pressed([KeyCode::KeyA, KeyCode::ArrowLeft]) {
+        velocity.x -= acceleration * delta_time;
+    }
+    if keyboard_input.any_pressed([KeyCode::KeyD, KeyCode::ArrowRight]) {
+        velocity.x += acceleration * delta_time;
+    }
+
+    Ok(())
+}
+
+pub fn quit(mut exit: EventWriter<AppExit>) {
+    exit.write(AppExit::Success);
+}
+
+pub fn move_camera(
+    mut camera: Single<&mut Transform, (Without<Player>, With<IsDefaultUiCamera>)>,
+    player: Single<&Transform, (With<Player>, Without<IsDefaultUiCamera>)>,
+) {
+    camera.translation = camera.translation.lerp(player.translation, 0.05);
+}

src/game/seed.rs

@@ -0,0 +1,22 @@
+use std::hash::{DefaultHasher, Hash, Hasher};
+
+use bevy::prelude::*;
+
+#[derive(Clone, Resource)]
+pub struct Seed(u64);
+
+impl From<String> for Seed {
+    fn from(value: String) -> Self {
+        Self(value.parse::<u64>().unwrap_or_else(|_| {
+            let mut state = DefaultHasher::new();
+            value.hash(&mut state);
+            state.finish()
+        }))
+    }
+}
+
+impl From<Seed> for [u8; 8] {
+    fn from(value: Seed) -> Self {
+        value.0.to_le_bytes()
+    }
+}

src/game/setup.rs

@@ -0,0 +1,110 @@
+use std::{f32::consts::PI, ops::Range};
+
+use avian2d::prelude::*;
+use bevy::{
+    color::palettes::{
+        css::WHITE,
+        tailwind::{LIME_400, RED_400},
+    },
+    prelude::*,
+};
+use bevy_rand::prelude::{GlobalEntropy, WyRand};
+use rand::Rng;
+use wyrand::WyRand as LocalRng;
+
+use super::objects::{Ball, Player, Wall};
+
+const BALL_COUNT: u8 = 32;
+const BALL_SIZES: Range<f32> = 10.0..25.0;
+const DIMENSION_SIZES: Range<f32> = 500.0..2000.0;
+
+#[derive(Resource)]
+pub struct PlayableArea(f32, f32);
+
+#[derive(Resource)]
+pub struct PlayerSize(f32);
+
+pub fn setup_pseudo_random(mut commands: Commands, mut rng: GlobalEntropy<WyRand>) {
+    commands.insert_resource(PlayerSize(rng.random_range(BALL_SIZES)));
+    commands.insert_resource(PlayableArea(
+        rng.random_range(DIMENSION_SIZES),
+        rng.random_range(DIMENSION_SIZES),
+    ));
+}
+
+pub fn setup_ui(mut commands: Commands) {
+    commands.spawn((Name::new("Camera"), Camera2d, IsDefaultUiCamera));
+}
+
+pub fn setup_player(
+    mut commands: Commands,
+    mut materials: ResMut<Assets<ColorMaterial>>,
+    mut meshes: ResMut<Assets<Mesh>>,
+    radius: Res<PlayerSize>,
+) {
+    let circle = Circle::new(radius.0);
+    commands.spawn((
+        Player,
+        Collider::from(circle),
+        Mesh2d(meshes.add(circle)),
+        MeshMaterial2d(materials.add(Color::from(LIME_400))),
+    ));
+}
+
+pub fn setup_balls(
+    mut commands: Commands,
+    mut materials: ResMut<Assets<ColorMaterial>>,
+    mut meshes: ResMut<Assets<Mesh>>,
+    region: Res<PlayableArea>,
+) {
+    let mut random = LocalRng::new(Default::default());
+    for _ in 0..BALL_COUNT {
+        let circle = Circle::new(random.random_range(BALL_SIZES));
+        commands.spawn((
+            Ball,
+            Collider::from(circle),
+            Mesh2d(meshes.add(circle)),
+            MeshMaterial2d(materials.add(Color::from(RED_400))),
+            Transform::from_xyz(
+                random.random_range(
+                    (-region.0 / 2.0 + circle.radius)..(region.0 / 2.0 - circle.radius),
+                ),
+                random.random_range(
+                    (-region.1 / 2.0 + circle.radius)..(region.1 / 2.0 - circle.radius),
+                ),
+                0.0,
+            ),
+        ));
+    }
+}
+
+pub fn setup_walls(
+    mut commands: Commands,
+    mut materials: ResMut<Assets<ColorMaterial>>,
+    mut meshes: ResMut<Assets<Mesh>>,
+    region: Res<PlayableArea>,
+) {
+    let thickness = 20.0;
+
+    for i in 0..4 {
+        let (offset, length) = if i % 2 == 0 {
+            (region.0, region.1 + thickness)
+        } else {
+            (region.1, region.0 + thickness)
+        };
+
+        let mut transform = Transform::from_xyz(0.0, offset / 2.0, 0.0);
+        transform.rotate_around(
+            Vec3::ZERO,
+            Quat::from_rotation_z(((i + 1) as f32) * PI / 2.0),
+        );
+
+        commands.spawn((
+            Wall,
+            Collider::rectangle(length, thickness),
+            Mesh2d(meshes.add(Rectangle::new(length, thickness))),
+            MeshMaterial2d(materials.add(Color::from(WHITE))),
+            transform,
+        ));
+    }
+}