Merge branch 'knarkzel/fix-npc-spawn' into 'master'

Fix bug that caused campfires and other stuff to duplicate

See merge request veloren/veloren!1543

CHANGELOG.md

@@ -81,6 +81,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Adjusted some keybindings
 - Consumables can now trigger multiple effects and buffs
 - Overhauled overworld spawns depending on chunk attributes
+- Fixed a bug which caused campfires and other stuff to duplicate
 
 ### Removed
 

common/src/comp/home_chunk.rs

@@ -0,0 +1,13 @@
+use specs::Component;
+use specs_idvs::IdvStorage;
+use vek::Vec2;
+
+/// This component exists in order to fix a bug that caused entitites
+/// such as campfires to duplicate because the chunk was double-loaded.
+/// See https://gitlab.com/veloren/veloren/-/merge_requests/1543
+#[derive(Copy, Clone, Default, Debug, PartialEq)]
+pub struct HomeChunk(pub Vec2<i32>);
+
+impl Component for HomeChunk {
+    type Storage = IdvStorage<Self>;
+}

common/src/comp/mod.rs

@@ -10,6 +10,7 @@ mod controller;
 mod energy;
 pub mod group;
 mod health;
+pub mod home_chunk;
 mod inputs;
 mod inventory;
 mod last;
@@ -47,6 +48,7 @@ pub use controller::{
 pub use energy::{Energy, EnergyChange, EnergySource};
 pub use group::Group;
 pub use health::{Health, HealthChange, HealthSource};
+pub use home_chunk::HomeChunk;
 pub use inputs::CanBuild;
 pub use inventory::{
     item,

common/src/event.rs

@@ -104,6 +104,7 @@ pub enum ServerEvent {
         agent: Option<comp::Agent>,
         alignment: comp::Alignment,
         scale: comp::Scale,
+        home_chunk: Option<comp::HomeChunk>,
         drop_item: Option<Item>,
     },
     CreateWaypoint(Vec3<f32>),

server/src/events/entity_creation.rs

@@ -2,7 +2,7 @@ use crate::{sys, Server, StateExt};
 use common::{
     character::CharacterId,
     comp::{
-        self, beam, shockwave, Agent, Alignment, Body, Gravity, Health, Item, ItemDrop,
+        self, beam, shockwave, Agent, Alignment, Body, Gravity, Health, HomeChunk, Item, ItemDrop,
         LightEmitter, Loadout, Ori, Pos, Projectile, Scale, Stats, Vel, WaypointArea,
     },
     outcome::Outcome,
@@ -49,6 +49,7 @@ pub fn handle_create_npc(
     alignment: Alignment,
     scale: Scale,
     drop_item: Option<Item>,
+    home_chunk: Option<HomeChunk>,
 ) {
     let group = match alignment {
         Alignment::Wild => None,
@@ -83,6 +84,12 @@ pub fn handle_create_npc(
         entity
     };
 
+    let entity = if let Some(home_chunk) = home_chunk {
+        entity.with(home_chunk)
+    } else {
+        entity
+    };
+
     entity.build();
 }
 

server/src/events/mod.rs

@@ -115,9 +115,11 @@ impl Server {
                     agent,
                     alignment,
                     scale,
+                    home_chunk,
                     drop_item,
                 } => handle_create_npc(
                     self, pos, stats, health, loadout, body, agent, alignment, scale, drop_item,
+                    home_chunk,
                 ),
                 ServerEvent::CreateWaypoint(pos) => handle_create_waypoint(self, pos),
                 ServerEvent::ClientDisconnect(entity) => {

server/src/lib.rs

@@ -54,7 +54,6 @@ use common::{
     },
     outcome::Outcome,
     recipe::default_recipe_book,
-    spiral::Spiral2d,
     state::{State, TimeOfDay},
     sync::WorldSyncExt,
     terrain::TerrainChunkSize,
@@ -197,6 +196,7 @@ impl Server {
         state.ecs_mut().register::<RegionSubscription>();
         state.ecs_mut().register::<Client>();
         state.ecs_mut().register::<Presence>();
+        state.ecs_mut().register::<comp::HomeChunk>();
 
         //Alias validator
         let banned_words_paths = &settings.banned_words_files;
@@ -524,19 +524,17 @@ impl Server {
                 &self.state.ecs().entities(),
                 &self.state.ecs().read_storage::<comp::Pos>(),
                 !&self.state.ecs().read_storage::<comp::Player>(),
+                &self.state.ecs().read_storage::<comp::HomeChunk>(),
             )
                 .join()
-                .filter(|(_, pos, _)| {
+                .filter(|(_, pos, _, home_chunk)| {
                     let chunk_key = terrain.pos_key(pos.0.map(|e| e.floor() as i32));
-                    // Check not only this chunk, but also all neighbours to avoid immediate
-                    // despawning if the entity walks outside of a valid chunk
-                    // briefly. If the entity isn't even near a loaded chunk then we get
-                    // rid of it.
-                    Spiral2d::new()
-                        .take(9)
-                        .all(|offs| terrain.get_key(chunk_key + offs).is_none())
+                    // Check if both this chunk and the NPCs `home_chunk` is unloaded. If so,
+                    // we delete them. We check for `home_chunk` in order to avoid duplicating
+                    // the entity under some circumstances.
+                    terrain.get_key(chunk_key).is_none() && terrain.get_key(home_chunk.0).is_none()
                 })
-                .map(|(entity, _, _)| entity)
+                .map(|(entity, _, _, _)| entity)
                 .collect::<Vec<_>>()
         };
 

server/src/sys/terrain.rs

@@ -187,6 +187,7 @@ impl<'a> System<'a> for Sys {
                     body,
                     alignment,
                     scale: comp::Scale(scale),
+                    home_chunk: Some(comp::HomeChunk(key)),
                     drop_item: entity.loot_drop,
                 })
             }