Make NPCs Aware of Sound - See Issue #913

CHANGELOG.md

@@ -60,6 +60,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Added timed bans and ban history.
 - Added non-admin moderators with limit privileges and updated the security model to reflect this.
 - Chat tabs
+- NPC's now hear certain sounds
 
 ### Changed
 

common/src/comp/agent.rs

@@ -14,6 +14,7 @@ use super::dialogue::Subject;
 
 pub const DEFAULT_INTERACTION_TIME: f32 = 3.0;
 pub const TRADE_INTERACTION_TIME: f32 = 300.0;
+pub const MAX_LISTEN_DIST: f32 = 100.0;
 
 #[derive(Copy, Clone, Debug, PartialEq)]
 pub enum Alignment {
@@ -245,7 +246,7 @@ pub enum AgentEvent {
     TradeAccepted(Uid),
     FinishedTrade(TradeResult),
     UpdatePendingTrade(
-        // this data structure is large so box it to keep AgentEvent small
+        // This data structure is large so box it to keep AgentEvent small
         Box<(
             TradeId,
             PendingTrade,
@@ -253,7 +254,43 @@ pub enum AgentEvent {
             [Option<ReducedInventory>; 2],
         )>,
     ),
-    // Add others here
+    ServerSound(Sound),
+}
+
+#[derive(Copy, Clone, Debug)]
+pub struct Sound {
+    pub kind: SoundKind,
+    pub pos: Vec3<f32>,
+    pub vol: f32,
+    pub time: f64,
+}
+
+impl Sound {
+    pub fn new(kind: SoundKind, pos: Vec3<f32>, vol: f32, time: f64) -> Self {
+        Sound {
+            kind,
+            pos,
+            vol,
+            time,
+        }
+    }
+
+    pub fn with_new_vol(mut self, new_vol: f32) -> Self {
+        self.vol = new_vol;
+
+        self
+    }
+}
+
+#[derive(Copy, Clone, Debug)]
+pub enum SoundKind {
+    Unknown,
+    Movement,
+    Melee,
+    Projectile,
+    Explosion,
+    Beam,
+    Shockwave,
 }
 
 #[derive(Clone, Debug)]
@@ -274,6 +311,8 @@ pub struct Agent {
     pub inbox: VecDeque<AgentEvent>,
     pub action_state: ActionState,
     pub bearing: Vec2<f32>,
+    pub sounds_heard: Vec<Sound>,
+    pub awareness: f32,
 }
 
 #[derive(Clone, Debug, Default)]

common/src/consts.rs

@@ -18,5 +18,8 @@ pub const IRON_DENSITY: f32 = 7870.0;
 pub const HUMAN_DENSITY: f32 = 990.0; // value we use to make humanoids gently float
 // 1 thread might be used for long-running cpu intensive tasks, like chunk
 // generation. having at least 2 helps not blocking in the main tick here
+
 pub const MIN_RECOMMENDED_RAYON_THREADS: usize = 2;
 pub const MIN_RECOMMENDED_TOKIO_THREADS: usize = 2;
+
+pub const SOUND_TRAVEL_DIST_PER_VOLUME: f32 = 3.0;

common/src/event.rs

@@ -2,6 +2,7 @@ use crate::{
     character::CharacterId,
     comp::{
         self,
+        agent::Sound,
         invite::{InviteKind, InviteResponse},
         item::Item,
         DisconnectReason, Ori, Pos,
@@ -175,6 +176,9 @@ pub enum ServerEvent {
         range: Option<f32>,
         pos: Pos,
     },
+    Sound {
+        sound: Sound,
+    },
 }
 
 pub struct EventBus<E> {

common/src/states/behavior.rs

@@ -69,7 +69,6 @@ pub trait CharacterBehavior {
             ControlAction::CancelInput(input) => self.cancel_input(data, input),
         }
     }
-    // fn init(data: &JoinData) -> CharacterState;
 }
 
 /// Read-Only Data sent from Character Behavior System to behavior fn's

common/systems/src/beam.rs

@@ -1,6 +1,7 @@
 use common::{
     combat::{AttackSource, AttackerInfo, TargetInfo},
     comp::{
+        agent::{Sound, SoundKind},
         Beam, BeamSegment, Body, CharacterState, Combo, Energy, Group, Health, HealthSource,
         Inventory, Ori, Pos, Scale, Stats,
     },
@@ -13,6 +14,7 @@ use common::{
     GroupTarget,
 };
 use common_ecs::{Job, Origin, ParMode, Phase, System};
+use rand::{thread_rng, Rng};
 use rayon::iter::ParallelIterator;
 use specs::{
     saveload::MarkerAllocator, shred::ResourceId, Entities, Join, ParJoin, Read, ReadExpect,
@@ -88,6 +90,14 @@ impl<'a> System<'a> for Sys {
                 None => return (server_events, add_hit_entities, outcomes),
             };
             let end_time = creation_time + beam_segment.duration.as_secs_f64();
+
+            let mut rng = thread_rng();
+            if rng.gen_bool(0.005) {
+                server_events.push(ServerEvent::Sound {
+                    sound: Sound::new(SoundKind::Beam, pos.0, 7.0, time),
+                });
+            }
+
             // If beam segment is out of time emit destroy event but still continue since it
             // may have traveled and produced effects a bit before reaching its
             // end point
@@ -151,8 +161,7 @@ impl<'a> System<'a> for Sys {
                 let height_b = body_b.height() * scale_b;
 
                 // Check if it is a hit
-                let hit = entity != target
-                    && !health_b.is_dead
+                let hit = entity != target && !health_b.is_dead
                     // Collision shapes
                     && sphere_wedge_cylinder_collision(pos.0, frame_start_dist, frame_end_dist, *ori.look_dir(), beam_segment.angle, pos_b.0, rad_b, height_b);
 

common/systems/src/melee.rs

@@ -1,11 +1,13 @@
 use common::{
     combat::{AttackSource, AttackerInfo, TargetInfo},
     comp::{
+        agent::{Sound, SoundKind},
         Body, CharacterState, Combo, Energy, Group, Health, Inventory, Melee, Ori, Pos, Scale,
         Stats,
     },
     event::{EventBus, ServerEvent},
     outcome::Outcome,
+    resources::Time,
     uid::Uid,
     util::Dir,
     GroupTarget,
@@ -18,6 +20,7 @@ use vek::*;
 
 #[derive(SystemData)]
 pub struct ReadData<'a> {
+    time: Read<'a, Time>,
     entities: Entities<'a>,
     uids: ReadStorage<'a, Uid>,
     positions: ReadStorage<'a, Pos>,
@@ -66,6 +69,9 @@ impl<'a> System<'a> for Sys {
             if melee_attack.applied {
                 continue;
             }
+            server_emitter.emit(ServerEvent::Sound {
+                sound: Sound::new(SoundKind::Melee, pos.0, 3.0, read_data.time.0),
+            });
             melee_attack.applied = true;
 
             // Scales

common/systems/src/projectile.rs

@@ -1,17 +1,19 @@
 use common::{
     combat::{AttackSource, AttackerInfo, TargetInfo},
     comp::{
+        agent::{Sound, SoundKind},
         projectile, Body, CharacterState, Combo, Energy, Group, Health, HealthSource, Inventory,
         Ori, PhysicsState, Pos, Projectile, Stats, Vel,
     },
     event::{EventBus, ServerEvent},
     outcome::Outcome,
-    resources::DeltaTime,
+    resources::{DeltaTime, Time},
     uid::{Uid, UidAllocator},
     util::Dir,
     GroupTarget,
 };
 use common_ecs::{Job, Origin, Phase, System};
+use rand::{thread_rng, Rng};
 use specs::{
     saveload::MarkerAllocator, shred::ResourceId, Entities, Join, Read, ReadStorage, SystemData,
     World, Write, WriteStorage,
@@ -21,6 +23,7 @@ use vek::*;
 
 #[derive(SystemData)]
 pub struct ReadData<'a> {
+    time: Read<'a, Time>,
     entities: Entities<'a>,
     dt: Read<'a, DeltaTime>,
     uid_allocator: Read<'a, UidAllocator>,
@@ -59,7 +62,6 @@ impl<'a> System<'a> for Sys {
         (read_data, mut orientations, mut projectiles, mut outcomes): Self::SystemData,
     ) {
         let mut server_emitter = read_data.server_bus.emitter();
-
         // Attacks
         'projectile_loop: for (entity, pos, physics, vel, mut projectile) in (
             &read_data.entities,
@@ -70,7 +72,15 @@ impl<'a> System<'a> for Sys {
         )
             .join()
         {
+            let mut rng = thread_rng();
+            if physics.on_surface().is_none() && rng.gen_bool(0.05) {
+                server_emitter.emit(ServerEvent::Sound {
+                    sound: Sound::new(SoundKind::Projectile, pos.0, 2.0, read_data.time.0),
+                });
+            }
+
             let mut projectile_vanished: bool = false;
+
             // Hit entity
             for other in physics.touch_entities.iter().copied() {
                 let same_group = projectile
@@ -86,16 +96,14 @@ impl<'a> System<'a> for Sys {
                         .and_then(|e| read_data.groups.get(e))
                     );
 
+                // Skip if in the same group
                 let target_group = if same_group {
                     GroupTarget::InGroup
                 } else {
                     GroupTarget::OutOfGroup
                 };
 
-                if projectile.ignore_group
-                    // Skip if in the same group
-                    && same_group
-                {
+                if projectile.ignore_group && same_group {
                     continue;
                 }
 
@@ -173,7 +181,7 @@ impl<'a> System<'a> for Sys {
                                 pos: pos.0,
                                 explosion: e,
                                 owner: projectile.owner,
-                            })
+                            });
                         },
                         projectile::Effect::Vanish => {
                             server_emitter.emit(ServerEvent::Destroy {
@@ -198,8 +206,7 @@ impl<'a> System<'a> for Sys {
                 }
             }
 
-            // Hit something solid
-            if physics.on_wall.is_some() || physics.on_ground || physics.on_ceiling {
+            if physics.on_surface().is_some() {
                 let projectile = &mut *projectile;
                 for effect in projectile.hit_solid.drain(..) {
                     match effect {
@@ -208,7 +215,7 @@ impl<'a> System<'a> for Sys {
                                 pos: pos.0,
                                 explosion: e,
                                 owner: projectile.owner,
-                            })
+                            });
                         },
                         projectile::Effect::Vanish => {
                             server_emitter.emit(ServerEvent::Destroy {

common/systems/src/shockwave.rs

@@ -1,6 +1,7 @@
 use common::{
     combat::{AttackSource, AttackerInfo, TargetInfo},
     comp::{
+        agent::{Sound, SoundKind},
         Body, CharacterState, Combo, Energy, Group, Health, HealthSource, Inventory, Ori,
         PhysicsState, Pos, Scale, Shockwave, ShockwaveHitEntities, Stats,
     },
@@ -12,6 +13,7 @@ use common::{
     GroupTarget,
 };
 use common_ecs::{Job, Origin, Phase, System};
+use rand::{thread_rng, Rng};
 use specs::{
     saveload::MarkerAllocator, shred::ResourceId, Entities, Join, Read, ReadStorage, SystemData,
     World, Write, WriteStorage,
@@ -83,9 +85,15 @@ impl<'a> System<'a> for Sys {
 
             let end_time = creation_time + shockwave.duration.as_secs_f64();
 
+            let mut rng = thread_rng();
+            if rng.gen_bool(0.05) {
+                server_emitter.emit(ServerEvent::Sound {
+                    sound: Sound::new(SoundKind::Shockwave, pos.0, 16.0, time),
+                });
+            }
+
             // If shockwave is out of time emit destroy event but still continue since it
-            // may have traveled and produced effects a bit before reaching it's
-            // end point
+            // may have traveled and produced effects a bit before reaching it's end point
             if time > end_time {
                 server_emitter.emit(ServerEvent::Destroy {
                     entity,

server/src/events/entity_manipulation.rs

@@ -1,7 +1,9 @@
 use crate::{
     client::Client,
     comp::{
-        biped_large, quadruped_low, quadruped_medium, quadruped_small, skills::SkillGroupKind,
+        agent::{Sound, SoundKind},
+        biped_large, quadruped_low, quadruped_medium, quadruped_small,
+        skills::SkillGroupKind,
         theropod, PhysicsState,
     },
     rtsim::RtSim,
@@ -476,19 +478,22 @@ pub fn handle_delete(server: &mut Server, entity: EcsEntity) {
 }
 
 pub fn handle_land_on_ground(server: &Server, entity: EcsEntity, vel: Vec3<f32>) {
-    let state = &server.state;
+    let ecs = server.state.ecs();
+
     if vel.z <= -30.0 {
-        let mass = state
-            .ecs()
+        let mass = ecs
             .read_storage::<comp::Mass>()
             .get(entity)
             .copied()
             .unwrap_or_default();
-        let inventories = state.ecs().read_storage::<Inventory>();
-        let falldmg = mass.0 * vel.z.powi(2) / 200.0;
-        let stats = state.ecs().read_storage::<Stats>();
+        let impact_energy = mass.0 * vel.z.powi(2) / 2.0;
+        let falldmg = impact_energy / 100.0;
+
+        let inventories = ecs.read_storage::<Inventory>();
+        let stats = ecs.read_storage::<Stats>();
+
         // Handle health change
-        if let Some(mut health) = state.ecs().write_storage::<comp::Health>().get_mut(entity) {
+        if let Some(mut health) = ecs.write_storage::<comp::Health>().get_mut(entity) {
             let damage = Damage {
                 source: DamageSource::Falling,
                 kind: DamageKind::Crushing,
@@ -503,7 +508,7 @@ pub fn handle_land_on_ground(server: &Server, entity: EcsEntity, vel: Vec3<f32>)
             health.change_by(change);
         }
         // Handle poise change
-        if let Some(mut poise) = state.ecs().write_storage::<comp::Poise>().get_mut(entity) {
+        if let Some(mut poise) = ecs.write_storage::<comp::Poise>().get_mut(entity) {
             let poise_damage = PoiseChange {
                 amount: -(mass.0 * vel.magnitude_squared() / 1500.0) as i32,
                 source: PoiseSource::Falling,
@@ -557,6 +562,13 @@ pub fn handle_respawn(server: &Server, entity: EcsEntity) {
 pub fn handle_explosion(server: &Server, pos: Vec3<f32>, explosion: Explosion, owner: Option<Uid>) {
     // Go through all other entities
     let ecs = &server.state.ecs();
+    let server_eventbus = ecs.read_resource::<EventBus<ServerEvent>>();
+    let time = ecs.read_resource::<Time>();
+
+    let explosion_volume = 2.5 * explosion.radius;
+    server_eventbus.emit_now(ServerEvent::Sound {
+        sound: Sound::new(SoundKind::Explosion, pos, explosion_volume, time.0),
+    });
 
     // Add an outcome
     // Uses radius as outcome power for now
@@ -751,8 +763,6 @@ pub fn handle_explosion(server: &Server, pos: Vec3<f32>, explosion: Explosion, o
                             char_state: char_state_b_maybe,
                         };
 
-                        let server_eventbus = ecs.read_resource::<EventBus<ServerEvent>>();
-
                         attack.apply_attack(
                             target_group,
                             attacker_info,

server/src/events/interaction.rs

@@ -1,13 +1,19 @@
-use specs::{world::WorldExt, Builder, Entity as EcsEntity};
+use specs::{world::WorldExt, Builder, Entity as EcsEntity, Join};
 use tracing::error;
 use vek::*;
 
 use common::{
     comp::{
-        self, agent::AgentEvent, dialogue::Subject, inventory::slot::EquipSlot, item, slot::Slot,
-        tool::ToolKind, Inventory, Pos,
+        self,
+        agent::{AgentEvent, Sound, MAX_LISTEN_DIST},
+        dialogue::Subject,
+        inventory::slot::EquipSlot,
+        item,
+        slot::Slot,
+        tool::ToolKind,
+        Inventory, Pos,
     },
-    consts::MAX_MOUNT_RANGE,
+    consts::{MAX_MOUNT_RANGE, SOUND_TRAVEL_DIST_PER_VOLUME},
     outcome::Outcome,
     uid::Uid,
     vol::ReadVol,
@@ -72,7 +78,7 @@ pub fn handle_npc_interaction(server: &mut Server, interactor: EcsEntity, npc_en
         if let Some(interactor_uid) = state.ecs().uid_from_entity(interactor) {
             agent
                 .inbox
-                .push_front(AgentEvent::Talk(interactor_uid, Subject::Regular));
+                .push_back(AgentEvent::Talk(interactor_uid, Subject::Regular));
         }
     }
 }
@@ -103,8 +109,7 @@ pub fn handle_mount(server: &mut Server, mounter: EcsEntity, mountee: EcsEntity)
                 state.ecs().uid_from_entity(mountee),
             ) {
                 // We know the entities must exist to be able to look up their UIDs, so these
-                // are guaranteed to work; hence we can ignore possible errors
-                // here.
+                // are guaranteed to work; hence we can ignore possible errors here.
                 state.write_component_ignore_entity_dead(
                     mountee,
                     comp::MountState::MountedBy(mounter_uid),
@@ -301,3 +306,27 @@ pub fn handle_mine_block(server: &mut Server, pos: Vec3<i32>, tool: Option<ToolK
         }
     }
 }
+
+pub fn handle_sound(server: &mut Server, sound: &Sound) {
+    let ecs = &server.state.ecs();
+    let positions = &ecs.read_storage::<comp::Pos>();
+    let agents = &mut ecs.write_storage::<comp::Agent>();
+
+    for (agent, agent_pos) in (agents, positions).join() {
+        // TODO: Use pathfinding for more dropoff around obstacles
+        let agent_dist_sqrd = agent_pos.0.distance_squared(sound.pos);
+        let sound_travel_dist_sqrd = (sound.vol * SOUND_TRAVEL_DIST_PER_VOLUME).powi(2);
+
+        let vol_dropoff = agent_dist_sqrd / sound_travel_dist_sqrd * sound.vol;
+        let propagated_sound = sound.with_new_vol(sound.vol - vol_dropoff);
+
+        let can_hear_sound = propagated_sound.vol > 0.00;
+        let should_hear_sound = agent_dist_sqrd < MAX_LISTEN_DIST.powi(2);
+
+        if can_hear_sound && should_hear_sound {
+            agent
+                .inbox
+                .push_back(AgentEvent::ServerSound(propagated_sound));
+        }
+    }
+}

server/src/events/invite.rs

@@ -132,7 +132,7 @@ pub fn handle_invite(
     } else if let Some(agent) = agents.get_mut(invitee) {
         if send_invite() {
             if let Some(inviter) = uids.get(inviter) {
-                agent.inbox.push_front(AgentEvent::TradeInvite(*inviter));
+                agent.inbox.push_back(AgentEvent::TradeInvite(*inviter));
                 invite_sent = true;
             }
         }
@@ -221,7 +221,7 @@ pub fn handle_invite_accept(server: &mut Server, entity: specs::Entity) {
                     if let Some(agent) = agents.get_mut(inviter) {
                         agent
                             .inbox
-                            .push_front(AgentEvent::TradeAccepted(invitee_uid));
+                            .push_back(AgentEvent::TradeAccepted(invitee_uid));
                     }
                     #[cfg(feature = "worldgen")]
                     let pricing = agents

server/src/events/mod.rs

@@ -14,7 +14,7 @@ use group_manip::handle_group;
 use information::handle_site_info;
 use interaction::{
     handle_lantern, handle_mine_block, handle_mount, handle_npc_interaction, handle_possess,
-    handle_unmount,
+    handle_sound, handle_unmount,
 };
 use inventory_manip::handle_inventory;
 use invite::{handle_invite, handle_invite_response};
@@ -110,7 +110,6 @@ impl Server {
                 },
                 ServerEvent::InitiateInvite(interactor, target, kind) => {
                     handle_invite(self, interactor, target, kind)
-                    //handle_initiate_trade(self, interactor, target)
                 },
                 ServerEvent::InviteResponse(entity, response) => {
                     handle_invite_response(self, entity, response)
@@ -217,10 +216,11 @@ impl Server {
                 ServerEvent::CreateSafezone { range, pos } => {
                     self.state.create_safezone(range, pos).build();
                 },
+                ServerEvent::Sound { sound } => handle_sound(self, &sound),
             }
         }
 
-        // Generate requested chunks.
+        // Generate requested chunks
         for (entity, key) in requested_chunks {
             self.generate_chunk(entity, key);
         }

server/src/events/trade.rs

@@ -25,7 +25,7 @@ fn notify_agent_simple(
     event: AgentEvent,
 ) {
     if let Some(agent) = agents.get_mut(entity) {
-        agent.inbox.push_front(event);
+        agent.inbox.push_back(event);
     }
 }
 
@@ -42,7 +42,7 @@ fn notify_agent_prices(
             // Box<(tid, pend, _, inventories)>) = event {
             agent
                 .inbox
-                .push_front(AgentEvent::UpdatePendingTrade(Box::new((
+                .push_back(AgentEvent::UpdatePendingTrade(Box::new((
                     // Prefer using this Agent's price data, but use the counterparty's price
                     // data if we don't have price data
                     boxval.0,

server/src/sys/agent.rs

@@ -2,7 +2,9 @@ use crate::rtsim::{Entity as RtSimData, RtSim};
 use common::{
     comp::{
         self,
-        agent::{AgentEvent, Target, DEFAULT_INTERACTION_TIME, TRADE_INTERACTION_TIME},
+        agent::{
+            AgentEvent, Target, DEFAULT_INTERACTION_TIME, MAX_LISTEN_DIST, TRADE_INTERACTION_TIME,
+        },
         buff::{BuffKind, Buffs},
         compass::{Direction, Distance},
         dialogue::{MoodContext, MoodState, Subject},
@@ -150,7 +152,6 @@ const FLEE_DURATION: f32 = 3.0;
 const MAX_FOLLOW_DIST: f32 = 12.0;
 const MAX_CHASE_DIST: f32 = 250.0;
 const MAX_FLEE_DIST: f32 = 20.0;
-const LISTEN_DIST: f32 = 16.0;
 const SEARCH_DIST: f32 = 48.0;
 const SIGHT_DIST: f32 = 80.0;
 const SNEAK_COEFFICIENT: f32 = 0.25;
@@ -158,6 +159,9 @@ const AVG_FOLLOW_DIST: f32 = 6.0;
 const RETARGETING_THRESHOLD_SECONDS: f64 = 10.0;
 const HEALING_ITEM_THRESHOLD: f32 = 0.5;
 const DEFAULT_ATTACK_RANGE: f32 = 2.0;
+const AWARENESS_INVESTIGATE_THRESHOLD: f32 = 1.0;
+const AWARENESS_DECREMENT_CONSTANT: f32 = 0.07;
+const SECONDS_BEFORE_FORGET_SOUNDS: f64 = 180.0;
 
 /// This system will allow NPCs to modify their controller
 #[derive(Default)]
@@ -479,8 +483,7 @@ impl<'a> System<'a> for Sys {
                                     {
                                         if let Some(tgt_pos) = read_data.positions.get(attacker) {
                                             // If the target is dead or in a safezone, remove the
-                                            // target
-                                            // and idle.
+                                            // target and idle.
                                             if should_stop_attacking(
                                                 read_data.healths.get(attacker),
                                                 read_data.buffs.get(attacker),
@@ -585,6 +588,9 @@ impl<'a> AgentData<'a> {
         read_data: &ReadData,
         event_emitter: &mut Emitter<'_, ServerEvent>,
     ) {
+        decrement_awareness(agent);
+        forget_old_sounds(agent, read_data);
+
         // Set owner if no target
         if agent.target.is_none() && thread_rng().gen_bool(0.1) {
             if let Some(Alignment::Owned(owner)) = self.alignment {
@@ -599,7 +605,12 @@ impl<'a> AgentData<'a> {
         }
         // Interact if incoming messages
         if !agent.inbox.is_empty() {
-            agent.action_state.timer = 0.1;
+            if !matches!(agent.inbox.front(), Some(AgentEvent::ServerSound(_))) {
+                agent.action_state.timer = 0.1;
+            } else if let Some(AgentEvent::ServerSound(sound)) = agent.inbox.pop_front() {
+                agent.sounds_heard.push(sound);
+                agent.awareness += sound.vol;
+            }
         }
         if agent.action_state.timer > 0.0 {
             if agent.action_state.timer
@@ -618,6 +629,8 @@ impl<'a> AgentData<'a> {
             }
         } else if thread_rng().gen::<f32>() < 0.1 {
             self.choose_target(agent, controller, &read_data, event_emitter);
+        } else if agent.awareness > AWARENESS_INVESTIGATE_THRESHOLD {
+            self.handle_elevated_awareness(agent, controller, read_data);
         } else {
             self.idle(agent, controller, &read_data);
         }
@@ -654,13 +667,8 @@ impl<'a> AgentData<'a> {
                         agent.action_state.timer = 0.01;
                     } else if agent.action_state.timer < FLEE_DURATION || dist_sqrd < MAX_FLEE_DIST
                     {
-                        self.flee(
-                            agent,
-                            controller,
-                            &read_data.terrain,
-                            tgt_pos,
-                            &read_data.dt,
-                        );
+                        self.flee(agent, controller, &read_data.terrain, tgt_pos);
+                        agent.action_state.timer += read_data.dt.0;
                     } else {
                         agent.action_state.timer = 0.0;
                         agent.target = None;
@@ -680,12 +688,10 @@ impl<'a> AgentData<'a> {
                             event_emitter
                                 .emit(ServerEvent::Chat(UnresolvedChatMsg::npc(*self.uid, msg)));
                         }
-
                         agent.target = None;
                     // Choose a new target every 10 seconds, but only for
                     // enemies
-                    // TODO: This should be more
-                    // principled. Consider factoring
+                    // TODO: This should be more principled. Consider factoring
                     // health, combat rating, wielded weapon, etc, into the
                     // decision to change target.
                     } else if read_data.time.0 - selected_at > RETARGETING_THRESHOLD_SECONDS
@@ -951,7 +957,8 @@ impl<'a> AgentData<'a> {
         //         .push(ControlEvent::InviteResponse(InviteResponse::Decline));
         // }
         agent.action_state.timer += read_data.dt.0;
-        let msg = agent.inbox.pop_back();
+
+        let msg = agent.inbox.pop_front();
         match msg {
             Some(AgentEvent::Talk(by, subject)) => {
                 if agent.behavior.can(BehaviorCapability::SPEAK) {
@@ -1304,9 +1311,9 @@ impl<'a> AgentData<'a> {
                     }
                 }
             },
-            None => {
+            _ => {
                 if agent.behavior.can(BehaviorCapability::SPEAK) {
-                    // no new events, continue looking towards the last interacting player for some
+                    // No new events, continue looking towards the last interacting player for some
                     // time
                     if let Some(Target { target, .. }) = &agent.target {
                         self.look_toward(controller, read_data, target);
@@ -1348,7 +1355,6 @@ impl<'a> AgentData<'a> {
         controller: &mut Controller,
         terrain: &TerrainGrid,
         tgt_pos: &Pos,
-        dt: &DeltaTime,
     ) {
         if let Some(body) = self.body {
             if body.can_strafe() && !self.is_gliding {
@@ -1375,7 +1381,6 @@ impl<'a> AgentData<'a> {
             self.jump_if(controller, bearing.z > 1.5);
             controller.inputs.move_z = bearing.z;
         }
-        agent.action_state.timer += dt.0;
     }
 
     /// Attempt to consume a healing item, and return whether any healing items
@@ -1457,7 +1462,7 @@ impl<'a> AgentData<'a> {
             })
             .filter(|(e, e_pos, e_health, e_stats, e_inventory, e_alignment, char_state)| {
                 let mut search_dist = SEARCH_DIST;
-                let mut listen_dist = LISTEN_DIST;
+                let mut listen_dist = MAX_LISTEN_DIST;
                 if char_state.map_or(false, |c_s| c_s.is_stealthy()) {
                     // TODO: make sneak more effective based on a stat like e_stats.fitness
                     search_dist *= SNEAK_COEFFICIENT;
@@ -3597,6 +3602,49 @@ impl<'a> AgentData<'a> {
             controller.inputs.move_z = bearing.z;
         }
     }
+
+    fn handle_elevated_awareness(
+        &self,
+        agent: &mut Agent,
+        controller: &mut Controller,
+        read_data: &ReadData,
+    ) {
+        // Currently this means that we are in a safezone
+        if invulnerability_is_in_buffs(read_data.buffs.get(*self.entity)) {
+            self.idle(agent, controller, &read_data);
+            return;
+        }
+
+        let is_enemy = matches!(self.alignment, Some(Alignment::Enemy));
+
+        if let Some(sound) = agent.sounds_heard.last() {
+            let sound_pos = Pos(sound.pos);
+            let dist_sqrd = self.pos.0.distance_squared(sound_pos.0);
+
+            if is_enemy {
+                let far_enough = dist_sqrd > 10.0_f32.powi(2);
+
+                if far_enough {
+                    self.follow(agent, controller, &read_data.terrain, &sound_pos);
+                } else {
+                    // TODO: Change this to a search action instead of idle
+                    self.idle(agent, controller, &read_data);
+                }
+            } else if self.flees {
+                let aggro = agent.psyche.aggro;
+                let close_enough = dist_sqrd < 35.0_f32.powi(2);
+                let loud_sound = sound.vol >= 10.0;
+
+                if close_enough && (aggro <= 0.5 || (aggro <= 0.7 && loud_sound)) {
+                    self.flee(agent, controller, &read_data.terrain, &sound_pos);
+                } else {
+                    self.idle(agent, controller, &read_data);
+                }
+            } else {
+                self.idle(agent, controller, &read_data);
+            }
+        }
+    }
 }
 
 fn can_see_tgt(terrain: &TerrainGrid, pos: &Pos, tgt_pos: &Pos, dist_sqrd: f32) -> bool {
@@ -3614,6 +3662,8 @@ fn should_stop_attacking(health: Option<&Health>, buffs: Option<&Buffs>) -> bool
     health.map_or(true, |a| a.is_dead) || invulnerability_is_in_buffs(buffs)
 }
 
+// FIXME: The logic that is used in this function and throughout the code
+// shouldn't be used to mean that a character is in a safezone.
 fn invulnerability_is_in_buffs(buffs: Option<&Buffs>) -> bool {
     buffs.map_or(false, |b| b.kinds.contains_key(&BuffKind::Invulnerability))
 }
@@ -3648,3 +3698,40 @@ fn aim_projectile(speed: f32, pos: Vec3<f32>, tgt: Vec3<f32>) -> Option<Dir> {
 
     Dir::from_unnormalized(to_tgt)
 }
+
+fn forget_old_sounds(agent: &mut Agent, read_data: &ReadData) {
+    if !agent.sounds_heard.is_empty() {
+        // Keep (retain) only newer sounds
+        agent
+            .sounds_heard
+            .retain(|&sound| read_data.time.0 - sound.time <= SECONDS_BEFORE_FORGET_SOUNDS);
+    }
+}
+
+fn decrement_awareness(agent: &mut Agent) {
+    let mut decrement = AWARENESS_DECREMENT_CONSTANT;
+    let awareness = agent.awareness;
+
+    let too_high = awareness >= 100.0;
+    let high = awareness >= 50.0;
+    let medium = awareness >= 30.0;
+    let low = awareness > 15.0;
+    let positive = awareness >= 0.0;
+    let negative = awareness < 0.0;
+
+    if too_high {
+        decrement *= 3.0;
+    } else if high {
+        decrement *= 1.0;
+    } else if medium {
+        decrement *= 2.5;
+    } else if low {
+        decrement *= 0.70;
+    } else if positive {
+        decrement *= 0.5;
+    } else if negative {
+        return;
+    }
+
+    agent.awareness -= decrement;
+}