run_if

src/entities/cargo/mod.rs

@@ -3,4 +3,4 @@ pub mod systems;
 
 pub use crate::world::tiles::tilemap::CargoPlaceError;
 pub use components::{Cargo, CarryVisualState, HaulSlot, Haulable};
-pub use systems::{carry_visual_system, haul_encumbrance_system};
+pub use systems::{any_hauling, carry_visual_system, haul_encumbrance_system};

src/entities/cargo/systems.rs

@@ -7,10 +7,17 @@ use crate::entities::item::inventory::constants::ENCUMBERED_SPEED_MULTIPLIER;
 use crate::entities::item::inventory::InventoryChangedEvent;
 use crate::entities::shared_components::Ambulatory;
 
+/// Returns true if any entity has an occupied HaulSlot.
+/// Used to gate carry_visual_system — skips entire system when no one is hauling.
+pub fn any_hauling(query: Query<&HaulSlot>) -> bool {
+    query.iter().any(|slot| slot.is_occupied())
+}
+
 /// Cycle the carry visual sprite while the entity's HaulSlot is occupied.
 /// When empty, ensure the normal sprite is restored.
 ///
 /// Runs in Update (visual only, no game state change).
+/// Only runs when at least one entity has an occupied HaulSlot.
 pub fn carry_visual_system(
     time: Res<Time>,
     mut query: Query<(&HaulSlot, &mut CarryVisualState, &mut Sprite)>,

src/main.rs

@@ -3,6 +3,7 @@ use bevy_rand::prelude::*;
 
 use crate::entities::{
     cargo::carry_visual_system,
+    cargo::any_hauling,
     item::{initialize_item_rotation_state, item_tile_management_system, ItemRotationTimer},
     shared_systems::digging::dig_system,
 };
@@ -71,6 +72,6 @@ fn main() {
             item_tile_management_system.after(initialize_item_rotation_state),
         )
         .add_systems(Update, debug::entity_dump::dump_entity_positions)
-        .add_systems(Update, carry_visual_system)
+        .add_systems(Update, carry_visual_system.run_if(any_hauling))
         .run();
 }