add game::JupiterPos resource

src/actor.rs

@@ -555,18 +555,12 @@ fn handle_wants_maxvelocity(
         &WantsMaxVelocity,
         Option<&OrbitsJupiter>,
     )>,
-    id2pos: Res<game::Id2Pos>,
+    jupiter_pos: Res<game::JupiterPos>,
 ) {
     let dt = time.delta_seconds();
-    let jupiter_pos: DVec3 = if let Some(jupiter_pos) = id2pos.0.get(cmd::ID_JUPITER) {
-        *jupiter_pos
-    } else {
-        warn!("Could not determine Jupiter's position");
-        DVec3::ZERO
-    };
     for (pos, mut v, engine, maxv, orbits_jupiter) in &mut query {
         let target_velocity = if orbits_jupiter.is_some() {
-            let relative_pos = pos.0 - jupiter_pos;
+            let relative_pos = pos.0 - jupiter_pos.0;
             nature::orbital_velocity(relative_pos, nature::JUPITER_MASS)
         } else {
             DVec3::ZERO
@@ -672,21 +666,15 @@ fn handle_gravity(
     time: Res<Time>,
     mut timer: ResMut<GravityUpdateTimer>,
     mut q_pos: Query<(&Position, &mut LinearVelocity), With<OrbitsJupiter>>,
-    id2pos: Res<game::Id2Pos>,
+    jupiter_pos: Res<game::JupiterPos>,
 ) {
     if !timer.0.tick(time.delta()).just_finished() {
         return;
     }
 
-    let pos_jupiter: DVec3 = if let Some(pos_jupiter) = id2pos.0.get(cmd::ID_JUPITER) {
-        *pos_jupiter
-    } else {
-        return;
-    };
-
     // this assumes prograde orbits for every object
     for (pos, mut v) in &mut q_pos {
-        let relative_pos = pos.0 - pos_jupiter;
+        let relative_pos = pos.0 - jupiter_pos.0;
         let accel = nature::gravitational_acceleration(relative_pos, nature::JUPITER_MASS);
         v.0 += accel;
     }

src/game.rs

@@ -32,6 +32,7 @@ impl Plugin for GamePlugin {
         );
         app.add_systems(Update, check_achievements);
         app.insert_resource(Id2Pos(HashMap::new()));
+        app.insert_resource(JupiterPos(DVec3::ZERO));
         app.insert_resource(var::AchievementTracker::default());
         app.insert_resource(var::Settings::default());
         app.insert_resource(var::GameVars::default());
@@ -50,6 +51,8 @@ pub struct PlayerDiesEvent(pub actor::DamageType);
 #[derive(Resource)]
 pub struct Id2Pos(pub HashMap<String, DVec3>);
 #[derive(Resource)]
+pub struct JupiterPos(pub DVec3);
+#[derive(Resource)]
 pub struct AchievementCheckTimer(pub Timer);
 
 #[derive(Event)]
@@ -351,10 +354,17 @@ fn handle_cheats(
     }
 }
 
-fn update_id2pos(mut id2pos: ResMut<Id2Pos>, q_id: Query<(&Position, &actor::Identifier)>) {
+fn update_id2pos(
+    mut id2pos: ResMut<Id2Pos>,
+    mut jupiterpos: ResMut<JupiterPos>,
+    q_id: Query<(&Position, &actor::Identifier)>,
+) {
     id2pos.0.clear();
     for (pos, id) in &q_id {
         id2pos.0.insert(id.0.clone(), pos.0);
+        if id.0 == "jupiter" {
+            jupiterpos.0 = pos.0;
+        }
     }
 }