initialize particle effect pooling

src/main.rs

@@ -1,6 +1,7 @@
 mod game;
 mod levels;
 mod menu;
+mod particle_effect;
 
 use bevy::{
 	core_pipeline::clear_color::ClearColorConfig,

src/particle_effect.rs

@@ -0,0 +1,57 @@
+use bevy::{prelude::*, sprite::Mesh2dHandle};
+
+pub struct ParticleEffectPlugin;
+
+impl Plugin for ParticleEffectPlugin {
+    fn build(&self, app: &mut App) {
+        app
+			.init_resource::<ParticleMesh>()
+            .insert_resource(PoolCount(1000))
+            .add_startup_system(particle_effect_startup);
+    }
+}
+
+pub struct ParticleMesh {
+	square: Mesh2dHandle,
+}
+
+impl FromWorld for ParticleMesh {
+	fn from_world(world: &mut World) -> Self {
+		let mut meshes = world.get_resource_mut::<Assets<Mesh>>().unwrap();
+		Self {
+			square: meshes
+				.add(Mesh::from(shape::Quad {
+					size: Vec2 { x: 4.0, y: 4.0 },
+					flip: false,
+				}))
+				.into(),
+		}
+	}
+}
+
+pub struct PoolCount(usize);
+
+#[derive(Component)]
+pub struct ParticleComponent;
+
+fn particle_effect_startup(
+    mut commands: Commands,
+
+	particle_mesh: Res<ParticleMesh>,
+    pool_count: ResMut<PoolCount>,
+	mut materials: ResMut<Assets<ColorMaterial>>,
+) {
+    for _p in 0 .. pool_count.0 {
+        let color_mesh = ColorMesh2dBundle {
+			mesh: particle_mesh.square.clone(),
+			material: materials.add(ColorMaterial::from(Color::WHITE)),
+            // default to invisible
+            visibility: Visibility {is_visible: false},
+			..default()
+		};
+
+        commands
+            .spawn_bundle(color_mesh)
+            .insert(ParticleComponent);
+    }
+}