use run condition for pausing

src/lib.rs

@@ -1,7 +1,6 @@
 use argh::FromArgs;
 use bevy::{
     prelude::*,
-    tasks::ParallelIterator,
     utils::{HashMap, HashSet},
 };
 use bevy_spatial::{kdtree::KDTree3, SpatialAccess};
@@ -80,12 +79,7 @@ pub fn update_vel(
     time: Res<Time>,
     positions: Res<Positions>,
     index: Res<NNTree>,
-    paused: Res<Paused>,
 ) {
-    if **paused {
-        return;
-    }
-
     let dt = time.delta_secs();
     let max_delta = MAX_DELTA_V * dt;
     toids
@@ -160,12 +154,7 @@ pub fn update_pos(
     mut positions: ResMut<Positions>,
     mut lookat: ResMut<LookAt>,
     time: Res<Time>,
-    paused: Res<Paused>,
 ) {
-    if **paused {
-        return;
-    }
-
     let mut new_look = Vec3::ZERO;
     let dt = time.delta_secs();
     for (mut xform, vel, entity) in toids.iter_mut() {

src/main.rs

@@ -29,7 +29,10 @@ fn main() {
         .insert_resource(Paused::default())
         .add_systems(Startup, (setup, setup_ambient_light))
         //.add_systems(Update, update_gizmos)
-        .add_systems(Update, (update_pos, update_buddies, update_vel))
+        .add_systems(
+            Update,
+            (update_pos, update_buddies, update_vel).run_if(not_paused),
+        )
         .add_systems(Update, (rotate_camera, close_on_esc))
         .run();
 }
@@ -42,12 +45,11 @@ fn setup(
     models: Res<AssetServer>,
 ) {
     let rand = &mut rand::thread_rng();
-    let cam = Camera3d::default();
 
     let camera = commands
         .spawn((
             Transform::from_xyz(0., 5.0, 25.).looking_at(Vec3::new(0.0, 5.0, 0.0), Vec3::Y),
-            cam,
+            Camera3d::default(),
             Visibility::Hidden,
         ))
         .id();
@@ -67,7 +69,8 @@ fn setup(
     // instructions
     commands.spawn((
         Text::new(
-            "Up and down for camera forward and back; hold shift to change height.\nLeft or right to move left or right.\nPress 'ESC' to quit; SPACE to pause."), TextFont {
+            "Up and down for camera forward and back; hold shift to change height.\nLeft or right to move left or right.\nPress 'ESC' to quit; SPACE to pause."),
+        TextFont {
         font_size: 20.0,
         ..Default::default()
         },
@@ -100,3 +103,7 @@ fn close_on_esc(
 fn setup_ambient_light(mut ambient_light: ResMut<AmbientLight>) {
     ambient_light.brightness = 100.0;
 }
+
+fn not_paused(paused: Option<Res<Paused>>) -> bool {
+    !paused.map(|p| **p).unwrap_or(false)
+}