Extract spatial indexing (tile contents, and if a tile is blocked) into its own module

src/ai/adjacent_ai_system.rs

@@ -1,8 +1,8 @@
 use ::specs::prelude::*;
 
 use crate::components::{Faction, MyTurn, Position, WantsToMelee};
-use crate::raws::Reaction;
+use crate::raws::{self, Reaction, RAWS};
-use crate::Map;
+use crate::{spatial, Map};
 
 pub struct AdjacentAI {}
 
@@ -116,21 +116,17 @@ impl<'a> System<'a> for AdjacentAI {
 
 fn evaluate(
     idx: usize,
-    map: &Map,
+    _map: &Map,
     factions: &ReadStorage<Faction>,
     my_faction: &str,
     reactions: &mut Vec<(Entity, Reaction)>,
 ) {
-    for other_entity in map.tile_content[idx].iter() {
+    spatial::for_each_tile_content(idx, |other_entity| {
-        if let Some(faction) = factions.get(*other_entity) {
+        if let Some(faction) = factions.get(other_entity) {
             reactions.push((
-                *other_entity,
+                other_entity,
-                crate::raws::faction_reaction(
+                raws::faction_reaction(my_faction, &faction.name, &RAWS.lock().unwrap()),
-                    my_faction,
-                    &faction.name,
-                    &crate::raws::RAWS.lock().unwrap(),
-                ),
             ))
         }
-    }
+    });
 }

src/ai/approach_ai_system.rs

@@ -2,7 +2,7 @@ use ::rltk::a_star_search;
 use ::specs::prelude::*;
 
 use crate::components::{EntityMoved, MyTurn, Position, Viewshed, WantsToApproach};
-use crate::Map;
+use crate::{spatial, Map};
 
 pub struct ApproachAI {}
 
@@ -12,7 +12,7 @@ impl<'a> System<'a> for ApproachAI {
         WriteStorage<'a, MyTurn>,
         WriteStorage<'a, WantsToApproach>,
         WriteStorage<'a, Position>,
-        WriteExpect<'a, Map>,
+        ReadExpect<'a, Map>,
         WriteStorage<'a, Viewshed>,
         WriteStorage<'a, EntityMoved>,
         Entities<'a>,
@@ -23,7 +23,7 @@ impl<'a> System<'a> for ApproachAI {
             mut turns,
             mut want_approach,
             mut positions,
-            mut map,
+            map,
             mut viewsheds,
             mut entity_moved,
             entities,
@@ -48,16 +48,15 @@ impl<'a> System<'a> for ApproachAI {
             );
 
             if path.success && path.steps.len() > 1 {
-                let mut idx = map.xy_idx(pos.x, pos.y);
+                let idx = map.xy_idx(pos.x, pos.y);
-                map.blocked[idx] = false;
                 pos.x = path.steps[1] as i32 % map.width;
                 pos.y = path.steps[1] as i32 / map.width;
                 entity_moved
                     .insert(entity, EntityMoved {})
                     .expect("Unable to insert moved marker");
 
-                idx = map.xy_idx(pos.x, pos.y);
+                let new_idx = map.xy_idx(pos.x, pos.y);
-                map.blocked[idx] = true;
+                spatial::move_entity(entity, idx, new_idx);
                 viewshed.dirty = true;
             }
         }

src/ai/chase_ai_system.rs

@@ -3,7 +3,7 @@ use std::collections::HashMap;
 use ::specs::prelude::*;
 
 use crate::components::{Chasing, EntityMoved, MyTurn, Position, Viewshed};
-use crate::Map;
+use crate::{spatial, Map};
 
 pub struct ChaseAI {}
 
@@ -13,22 +13,15 @@ impl<'a> System<'a> for ChaseAI {
         WriteStorage<'a, MyTurn>,
         WriteStorage<'a, Chasing>,
         WriteStorage<'a, Position>,
-        WriteExpect<'a, Map>,
+        ReadExpect<'a, Map>,
         WriteStorage<'a, Viewshed>,
         WriteStorage<'a, EntityMoved>,
         Entities<'a>,
     );
 
     fn run(&mut self, data: Self::SystemData) {
-        let (
+        let (mut turns, mut chasing, mut positions, map, mut viewsheds, mut entity_moved, entities) =
-            mut turns,
+            data;
-            mut chasing,
-            mut positions,
-            mut map,
-            mut viewsheds,
-            mut entity_moved,
-            entities,
-        ) = data;
 
         let mut targets: HashMap<Entity, (i32, i32)> = HashMap::new();
         let mut end_chase: Vec<Entity> = Vec::new();
@@ -58,17 +51,16 @@ impl<'a> System<'a> for ChaseAI {
             );
 
             if path.success && path.steps.len() > 1 && path.steps.len() < 15 {
-                let mut idx = map.xy_idx(pos.x, pos.y);
+                let idx = map.xy_idx(pos.x, pos.y);
-                map.blocked[idx] = false;
                 pos.x = path.steps[1] as i32 % map.width;
                 pos.y = path.steps[1] as i32 / map.width;
                 entity_moved
                     .insert(entity, EntityMoved {})
                     .expect("Unable to insert movement marker");
 
-                idx = map.xy_idx(pos.x, pos.y);
+                let new_idx = map.xy_idx(pos.x, pos.y);
-                map.blocked[idx] = true;
                 viewshed.dirty = true;
+                spatial::move_entity(entity, idx, new_idx);
                 turn_done.push(entity);
             } else {
                 end_chase.push(entity);

src/ai/default_move_system.rs

@@ -2,7 +2,7 @@ use ::rltk::RandomNumberGenerator;
 use ::specs::prelude::*;
 
 use crate::components::{EntityMoved, MoveMode, Movement, MyTurn, Position, Viewshed};
-use crate::{tile_walkable, Map};
+use crate::{spatial, tile_walkable, Map};
 
 pub struct DefaultMoveAI {}
 
@@ -12,7 +12,7 @@ impl<'a> System<'a> for DefaultMoveAI {
         WriteStorage<'a, MyTurn>,
         WriteStorage<'a, MoveMode>,
         WriteStorage<'a, Position>,
-        WriteExpect<'a, Map>,
+        ReadExpect<'a, Map>,
         WriteStorage<'a, Viewshed>,
         WriteStorage<'a, EntityMoved>,
         WriteExpect<'a, RandomNumberGenerator>,
@@ -24,7 +24,7 @@ impl<'a> System<'a> for DefaultMoveAI {
             mut turns,
             mut move_mode,
             mut positions,
-            mut map,
+            map,
             mut viewsheds,
             mut entity_moved,
             mut rng,
@@ -59,15 +59,14 @@ impl<'a> System<'a> for DefaultMoveAI {
 
                     if x > 0 && x < map.width - 1 && y > 0 && y < map.height - 1 {
                         let dest_idx = map.xy_idx(x, y);
-                        if !map.blocked[dest_idx] {
+                        if !spatial::is_blocked(dest_idx) {
                             let idx = map.xy_idx(pos.x, pos.y);
-                            map.blocked[idx] = false;
                             pos.x = x;
                             pos.y = y;
                             entity_moved
                                 .insert(entity, EntityMoved {})
                                 .expect("Unable to insert movement marker");
-                            map.blocked[dest_idx] = true;
+                            crate::spatial::move_entity(entity, idx, dest_idx);
                             viewshed.dirty = true;
                         }
                     }
@@ -75,18 +74,17 @@ impl<'a> System<'a> for DefaultMoveAI {
                 Movement::RandomWaypoint { path } => {
                     if let Some(path) = path {
                         // We have a target - go there
-                        let mut idx = map.xy_idx(pos.x, pos.y);
+                        let idx = map.xy_idx(pos.x, pos.y);
                         if path.len() > 1 {
-                            if !map.blocked[path[1]] {
+                            if !spatial::is_blocked(path[1]) {
-                                map.blocked[idx] = false;
                                 pos.x = (path[1] as i32 % map.width) as i32;
                                 pos.y = (path[1] as i32 / map.width) as i32;
                                 entity_moved
                                     .insert(entity, EntityMoved {})
                                     .expect("Unable to insert movement marker");
 
-                                idx = map.xy_idx(pos.x, pos.y);
+                                let new_idx = map.xy_idx(pos.x, pos.y);
-                                map.blocked[idx] = true;
+                                spatial::move_entity(entity, idx, new_idx);
                                 viewshed.dirty = true;
                                 path.remove(0); // Remove the first step in the path
                             }

src/ai/flee_ai_system.rs

@@ -2,7 +2,7 @@ use ::rltk::DijkstraMap;
 use ::specs::prelude::*;
 
 use crate::components::{EntityMoved, MyTurn, Position, Viewshed, WantsToFlee};
-use crate::Map;
+use crate::{spatial, Map};
 
 pub struct FleeAI {}
 
@@ -46,9 +46,8 @@ impl<'a> System<'a> for FleeAI {
 
             let flee_map = DijkstraMap::new(map.width, map.height, &flee.indices, &*map, 100.0);
             if let Some(flee_target) = DijkstraMap::find_highest_exit(&flee_map, my_idx, &*map) {
-                if !map.blocked[flee_target] {
+                if !spatial::is_blocked(flee_target) {
-                    map.blocked[my_idx] = false;
+                    spatial::move_entity(entity, my_idx, flee_target);
-                    map.blocked[flee_target] = true;
                     viewshed.dirty = true;
                     pos.x = flee_target as i32 % map.width;
                     pos.y = flee_target as i32 / map.width;

src/ai/visible_ai_system.rs

@@ -3,8 +3,8 @@ use ::specs::prelude::*;
 use crate::components::{
     Chasing, Faction, MyTurn, Position, Viewshed, WantsToApproach, WantsToFlee,
 };
-use crate::raws::Reaction;
+use crate::raws::{self, Reaction, RAWS};
-use crate::Map;
+use crate::{spatial, Map};
 
 pub struct VisibleAI {}
 
@@ -87,22 +87,18 @@ impl<'a> System<'a> for VisibleAI {
 
 fn evaluate(
     idx: usize,
-    map: &Map,
+    _map: &Map,
     factions: &ReadStorage<Faction>,
     my_faction: &str,
     reactions: &mut Vec<(usize, Reaction, Entity)>,
 ) {
-    for other_entity in map.tile_content[idx].iter() {
+    spatial::for_each_tile_content(idx, |other_entity| {
-        if let Some(faction) = factions.get(*other_entity) {
+        if let Some(faction) = factions.get(other_entity) {
             reactions.push((
                 idx,
-                crate::raws::faction_reaction(
+                raws::faction_reaction(my_faction, &faction.name, &RAWS.lock().unwrap()),
-                    my_faction,
+                other_entity,
-                    &faction.name,
-                    &crate::raws::RAWS.lock().unwrap(),
-                ),
-                *other_entity,
             ));
         }
-    }
+    });
 }

src/inventory_system.rs

@@ -4,7 +4,7 @@ use ::specs::prelude::*;
 use crate::components::*;
 use crate::game_log::GameLog;
 use crate::particle_system::ParticleBuilder;
-use crate::{Map, RunState};
+use crate::{spatial, Map, RunState};
 
 pub struct ItemCollectionSystem {}
 
@@ -116,9 +116,7 @@ impl<'a> System<'a> for ItemUseSystem {
                         None => {
                             // Single target in tile
                             let idx = map.xy_idx(target.x, target.y);
-                            for mob in map.tile_content[idx].iter() {
+                            spatial::for_each_tile_content(idx, |mob| targets.push(mob));
-                                targets.push(*mob);
-                            }
                         }
                         Some(area_effect) => {
                             // AoE
@@ -130,9 +128,7 @@ impl<'a> System<'a> for ItemUseSystem {
 
                             for tile_idx in blast_tiles.iter() {
                                 let idx = map.xy_idx(tile_idx.x, tile_idx.y);
-                                for mob in map.tile_content[idx].iter() {
+                                spatial::for_each_tile_content(idx, |mob| targets.push(mob));
-                                    targets.push(*mob);
-                                }
 
                                 particle_builder.request(
                                     tile_idx.x,

src/main.rs

@@ -19,6 +19,7 @@ pub mod raws;
 mod rect;
 mod rex_assets;
 pub mod saveload_system;
+mod spatial;
 mod spawner;
 mod trigger_system;
 mod visibility_system;

src/map.rs

@@ -6,13 +6,13 @@ use std::collections::HashSet;
 
 use ::rltk::{Algorithm2D, BaseMap, Point, SmallVec};
 use ::serde::{Deserialize, Serialize};
-use ::specs::prelude::*;
 pub use dungeon::*;
 use rltk::RGB;
 pub use themes::*;
 pub use tiletype::{tile_opaque, tile_walkable, TileType};
 
 use crate::map::tiletype::tile_cost;
+use crate::spatial;
 
 #[derive(Default, Serialize, Deserialize, Clone)]
 pub struct Map {
@@ -21,17 +21,12 @@ pub struct Map {
     pub height: i32,
     pub revealed_tiles: Vec<bool>,
     pub visible_tiles: Vec<bool>,
-    pub blocked: Vec<bool>,
     pub depth: i32,
     pub bloodstains: HashSet<usize>,
     pub view_blocked: HashSet<usize>,
     pub name: String,
     pub outdoors: bool,
     pub light: Vec<RGB>,
-
-    #[serde(skip_serializing)]
-    #[serde(skip_deserializing)]
-    pub tile_content: Vec<Vec<Entity>>,
 }
 
 impl Map {
@@ -46,24 +41,21 @@ impl Map {
 
         let idx = self.xy_idx(x, y);
 
-        !self.blocked[idx]
+        !spatial::is_blocked(idx)
     }
 
     pub fn populate_blocked(&mut self) {
-        for (i, tile) in self.tiles.iter_mut().enumerate() {
+        spatial::populate_blocked_from_map(self);
-            self.blocked[i] = !tile_walkable(*tile);
-        }
     }
 
     pub fn clear_content_index(&mut self) {
-        for content in self.tile_content.iter_mut() {
+        spatial::clear();
-            content.clear();
-        }
     }
 
     /// Generates an empty map, consisting entirely of solid walls
     pub fn new<S: ToString>(new_depth: i32, width: i32, height: i32, name: S) -> Map {
         let map_tile_count = (width * height) as usize;
+        crate::spatial::set_size(map_tile_count);
 
         Map {
             tiles: vec![TileType::Wall; map_tile_count],
@@ -71,8 +63,6 @@ impl Map {
             height,
             revealed_tiles: vec![false; map_tile_count],
             visible_tiles: vec![false; map_tile_count],
-            blocked: vec![false; map_tile_count],
-            tile_content: vec![Vec::new(); map_tile_count],
             depth: new_depth,
             bloodstains: HashSet::new(),
             view_blocked: HashSet::new(),

src/map/dungeon.rs

@@ -26,10 +26,7 @@ impl MasterDungeonMap {
 
     pub fn get_map(&self, depth: i32) -> Option<Map> {
         if self.maps.contains_key(&depth) {
-            let mut result = self.maps[&depth].clone();
+            Some(self.maps[&depth].clone())
-            result.tile_content = vec![Vec::new(); (result.width * result.height) as usize];
-
-            Some(result)
         } else {
             None
         }

src/map_indexing_system.rs

@@ -1,33 +1,26 @@
 use ::specs::prelude::*;
 
-use crate::{BlocksTile, Map, Position};
+use crate::{spatial, BlocksTile, Map, Position};
 
 pub struct MapIndexingSystem {}
 
 impl<'a> System<'a> for MapIndexingSystem {
     type SystemData = (
-        WriteExpect<'a, Map>,
+        ReadExpect<'a, Map>,
         ReadStorage<'a, Position>,
         ReadStorage<'a, BlocksTile>,
         Entities<'a>,
     );
 
     fn run(&mut self, data: Self::SystemData) {
-        let (mut map, position, blockers, entities) = data;
+        let (map, position, blockers, entities) = data;
 
-        map.populate_blocked();
+        spatial::clear();
-        map.clear_content_index();
+        spatial::populate_blocked_from_map(&*map);
 
         for (entity, position) in (&entities, &position).join() {
             let idx = map.xy_idx(position.x, position.y);
-
+            spatial::index_entity(entity, idx, blockers.get(entity).is_some());
-            // If it's a blocking entity, note that in the map object
-            if let Some(_p) = blockers.get(entity) {
-                map.blocked[idx] = true;
-            }
-
-            // Push a copy of the entity to the indexed slot
-            map.tile_content[idx].push(entity);
         }
     }
 }

src/player.rs

@@ -8,8 +8,8 @@ use crate::components::{
     Item, Player, Pools, Position, Renderable, Viewshed, WantsToMelee, WantsToPickupItem,
 };
 use crate::game_log::GameLog;
-use crate::raws::Reaction;
+use crate::raws::{self, Reaction, RAWS};
-use crate::{Map, RunState, State, TileType};
+use crate::{spatial, Map, RunState, State, TileType};
 
 pub fn try_move_player(delta_x: i32, delta_y: i32, ecs: &mut World) -> RunState {
     let mut positions = ecs.write_storage::<Position>();
@@ -41,14 +41,15 @@ pub fn try_move_player(delta_x: i32, delta_y: i32, ecs: &mut World) -> RunState
         }
         let destination_idx = map.xy_idx(pos.x + delta_x, pos.y + delta_y);
 
-        for potential_target in map.tile_content[destination_idx].iter() {
+        result =
+            spatial::for_each_tile_content_with_gamemode(destination_idx, |potential_target| {
                 let mut hostile = true;
-            if combat_stats.get(*potential_target).is_some() {
+                if combat_stats.get(potential_target).is_some() {
-                if let Some(faction) = factions.get(*potential_target) {
+                    if let Some(faction) = factions.get(potential_target) {
                         let reaction = crate::raws::faction_reaction(
                             &faction.name,
                             "Player",
-                        &crate::raws::RAWS.lock().unwrap(),
+                            &RAWS.lock().unwrap(),
                         );
                         if reaction != Reaction::Attack {
                             hostile = false;
@@ -57,7 +58,7 @@ pub fn try_move_player(delta_x: i32, delta_y: i32, ecs: &mut World) -> RunState
                 }
                 if !hostile {
                     // Note that we want to move the bystander
-                swap_entities.push((*potential_target, pos.x, pos.y));
+                    swap_entities.push((potential_target, pos.x, pos.y));
 
                     // Move the player
                     pos.x = min(map.width - 1, max(0, pos.x + delta_x));
@@ -70,39 +71,44 @@ pub fn try_move_player(delta_x: i32, delta_y: i32, ecs: &mut World) -> RunState
                     let mut ppos = ecs.write_resource::<Point>();
                     ppos.x = pos.x;
                     ppos.y = pos.y;
-            } else {
+
-                let target = combat_stats.get(*potential_target);
+                    return Some(RunState::Ticking);
-                if let Some(_target) = target {
+                } else if combat_stats.get(potential_target).is_some() {
                     wants_to_melee
                         .insert(
                             entity,
                             WantsToMelee {
-                                target: *potential_target,
+                                target: potential_target,
                             },
                         )
                         .expect("Add target failed");
 
-                    return RunState::Ticking;
+                    return Some(RunState::Ticking);
-                }
-            }
-            let door = doors.get_mut(*potential_target);
-            if let Some(door) = door {
-                door.open = true;
-                blocks_visibility.remove(*potential_target);
-                blocks_movement.remove(*potential_target);
-                let glyph = renderables.get_mut(*potential_target).unwrap();
-                glyph.glyph = rltk::to_cp437('/');
-                viewshed.dirty = true;
-                result = RunState::Ticking;
-            }
                 }
 
-        if !map.blocked[destination_idx] {
+                if let Some(door) = doors.get_mut(potential_target) {
+                    door.open = true;
+                    blocks_visibility.remove(potential_target);
+                    blocks_movement.remove(potential_target);
+                    let glyph = renderables.get_mut(potential_target).unwrap();
+                    glyph.glyph = rltk::to_cp437('/');
+                    viewshed.dirty = true;
+
+                    return Some(RunState::Ticking);
+                }
+
+                None
+            });
+
+        if !spatial::is_blocked(destination_idx) {
+            let old_idx = map.xy_idx(pos.x, pos.y);
             pos.x = min(map.width - 1, max(0, pos.x + delta_x));
             pos.y = min(map.height - 1, max(0, pos.y + delta_y));
+            let new_idx = map.xy_idx(pos.x, pos.y);
             entity_moved
                 .insert(entity, EntityMoved {})
                 .expect("Failed to add EntityMoved flag to player");
+            spatial::move_entity(entity, old_idx, new_idx);
 
             viewshed.dirty = true;
             let mut ppos = ecs.write_resource::<Point>();
@@ -120,8 +126,13 @@ pub fn try_move_player(delta_x: i32, delta_y: i32, ecs: &mut World) -> RunState
     for m in swap_entities.iter() {
         let their_pos = positions.get_mut(m.0);
         if let Some(their_pos) = their_pos {
+            let old_idx = map.xy_idx(their_pos.x, their_pos.y);
             their_pos.x = m.1;
             their_pos.y = m.2;
+            let new_idx = map.xy_idx(their_pos.x, their_pos.y);
+            spatial::move_entity(m.0, old_idx, new_idx);
+
+            result = RunState::Ticking;
         }
     }
 
@@ -205,21 +216,16 @@ fn skip_turn(ecs: &mut World) -> RunState {
     let viewshed = viewshed_components.get(*player_entity).unwrap();
     for tile in viewshed.visible_tiles.iter() {
         let idx = worldmap_resource.xy_idx(tile.x, tile.y);
-        for entity_id in worldmap_resource.tile_content[idx].iter() {
+        spatial::for_each_tile_content(idx, |entity_id| match factions.get(entity_id) {
-            match factions.get(*entity_id) {
             None => {}
             Some(faction) => {
-                    let reaction = crate::raws::faction_reaction(
+                let reaction =
-                        &faction.name,
+                    raws::faction_reaction(&faction.name, "Player", &RAWS.lock().unwrap());
-                        "Player",
-                        &crate::raws::RAWS.lock().unwrap(),
-                    );
                 if reaction == Reaction::Attack {
                     can_heal = false;
                 }
             }
-            }
+        });
-        }
     }
 
     // Don't allow healing when hungry or starving

src/saveload_system.rs

@@ -11,6 +11,7 @@ use ::specs::saveload::{
 
 use crate::components::*;
 use crate::map::{Map, MasterDungeonMap};
+use crate::spatial;
 
 macro_rules! serialize_individually {
     ($ecs:expr, $ser:expr, $data:expr, $( $type:ty),*,) => {
@@ -233,7 +234,7 @@ pub fn load_game(ecs: &mut World) {
         for (e, h) in (&entities, &helper).join() {
             let mut worldmap = ecs.write_resource::<Map>();
             *worldmap = h.map.clone();
-            worldmap.tile_content = vec![Vec::new(); (worldmap.height * worldmap.width) as usize];
+            spatial::set_size((worldmap.height * worldmap.width) as usize);
             deleteme = Some(e);
         }
         for (e, h) in (&entities, &helper2).join() {

src/spatial.rs

@@ -0,0 +1,121 @@
+use std::sync::Mutex;
+
+use ::specs::prelude::*;
+
+use crate::{tile_walkable, Map, RunState};
+
+struct SpatialMap {
+    blocked: Vec<(bool, bool)>,
+    tile_content: Vec<Vec<(Entity, bool)>>,
+}
+
+impl SpatialMap {
+    fn new() -> Self {
+        Self {
+            blocked: Vec::new(),
+            tile_content: Vec::new(),
+        }
+    }
+}
+
+lazy_static! {
+    static ref SPATIAL_MAP: Mutex<SpatialMap> = Mutex::new(SpatialMap::new());
+}
+
+pub fn set_size(map_tile_count: usize) {
+    let mut lock = SPATIAL_MAP.lock().unwrap();
+    lock.blocked = vec![(false, false); map_tile_count];
+    lock.tile_content = vec![Vec::new(); map_tile_count];
+}
+
+pub fn clear() {
+    let mut lock = SPATIAL_MAP.lock().unwrap();
+    lock.blocked.iter_mut().for_each(|b| {
+        b.0 = false;
+        b.1 = false;
+    });
+    for content in lock.tile_content.iter_mut() {
+        content.clear();
+    }
+}
+
+pub fn populate_blocked_from_map(map: &Map) {
+    let mut lock = SPATIAL_MAP.lock().unwrap();
+    for (i, tile) in map.tiles.iter().enumerate() {
+        lock.blocked[i].0 = !tile_walkable(*tile);
+    }
+}
+
+pub fn index_entity(entity: Entity, idx: usize, blocks_tile: bool) {
+    let mut lock = SPATIAL_MAP.lock().unwrap();
+    lock.tile_content[idx].push((entity, blocks_tile));
+    if blocks_tile {
+        lock.blocked[idx].1 = true;
+    }
+}
+
+pub fn is_blocked(idx: usize) -> bool {
+    let lock = SPATIAL_MAP.lock().unwrap();
+
+    lock.blocked[idx].0 || lock.blocked[idx].1
+}
+
+pub fn for_each_tile_content<F>(idx: usize, mut f: F)
+where
+    F: FnMut(Entity),
+{
+    let lock = SPATIAL_MAP.lock().unwrap();
+    for entity in lock.tile_content[idx].iter() {
+        f(entity.0);
+    }
+}
+
+pub fn for_each_tile_content_with_gamemode<F>(idx: usize, mut f: F) -> RunState
+where
+    F: FnMut(Entity) -> Option<RunState>,
+{
+    let lock = SPATIAL_MAP.lock().unwrap();
+    for entity in lock.tile_content[idx].iter() {
+        if let Some(rs) = f(entity.0) {
+            return rs;
+        }
+    }
+
+    RunState::AwaitingInput
+}
+
+/// Move an entity on the map from `moving_from` index to the `moving_to` index.
+/// This also recalculates if these two tiles are blocked based on the entities
+/// within these tiles.
+pub fn move_entity(entity: Entity, moving_from: usize, moving_to: usize) {
+    let mut lock = SPATIAL_MAP.lock().unwrap();
+    let mut entity_blocks = false;
+
+    lock.tile_content[moving_from].retain(|(e, blocks)| {
+        if *e == entity {
+            entity_blocks = *blocks;
+            false
+        } else {
+            true
+        }
+    });
+    lock.tile_content[moving_to].push((entity, entity_blocks));
+
+    // Recalculate blocks for both tiles
+    let mut from_blocked = false;
+    let mut to_blocked = false;
+    lock.tile_content[moving_from]
+        .iter()
+        .for_each(|(_, blocks)| {
+            if *blocks {
+                from_blocked = true;
+            }
+        });
+    lock.tile_content[moving_to].iter().for_each(|(_, blocks)| {
+        if *blocks {
+            to_blocked = true;
+        }
+    });
+    lock.blocked[moving_from].1 = from_blocked;
+    lock.blocked[moving_to].1 = to_blocked;
+}

src/trigger_system.rs

@@ -6,7 +6,7 @@ use crate::components::{
 };
 use crate::game_log::GameLog;
 use crate::particle_system::ParticleBuilder;
-use crate::Map;
+use crate::{spatial, Map};
 
 pub struct TriggerSystem {}
 
@@ -48,22 +48,22 @@ impl<'a> System<'a> for TriggerSystem {
         for (entity, mut _entity_moved, pos) in (&entities, &mut entity_moved, &position).join() {
             let idx = map.xy_idx(pos.x, pos.y);
 
-            for entity_id in map.tile_content[idx].iter() {
+            spatial::for_each_tile_content(idx, |entity_id| {
                 // Do not bother to check yourself for being a trap!
-                if entity != *entity_id {
+                if entity != entity_id {
-                    match entry_trigger.get(*entity_id) {
+                    match entry_trigger.get(entity_id) {
                         None => {}
                         Some(_trigger) => {
                             // We triggered it
-                            if let Some(name) = names.get(*entity_id) {
+                            if let Some(name) = names.get(entity_id) {
                                 log.append(format!("{} triggers!", &name.name));
                             }
 
                             // The trap is no longer hidden
-                            hidden.remove(*entity_id);
+                            hidden.remove(entity_id);
 
                             // If the trap is damage inflicting, do it
-                            if let Some(damage) = inflicts_damage.get(*entity_id) {
+                            if let Some(damage) = inflicts_damage.get(entity_id) {
                                 particle_builder.request(
                                     pos.x,
                                     pos.y,
@@ -82,13 +82,13 @@ impl<'a> System<'a> for TriggerSystem {
                             }
 
                             // If it is single activation, it needs to be removed
-                            if let Some(_sa) = single_activation.get(*entity_id) {
+                            if single_activation.get(entity_id).is_some() {
-                                remove_entities.push(*entity_id);
+                                remove_entities.push(entity_id);
-                            }
                             }
                         }
                     }
                 }
+            });
         }
 
         // Remove any single activation traps

src/visibility_system.rs

@@ -3,7 +3,7 @@ use ::specs::prelude::*;
 
 use crate::components::{BlocksVisibility, Hidden, Name};
 use crate::game_log::GameLog;
-use crate::{Map, Player, Position, Viewshed};
+use crate::{spatial, Map, Player, Position, Viewshed};
 
 pub struct VisibilitySystem {}
 
@@ -53,7 +53,7 @@ impl<'a> System<'a> for VisibilitySystem {
                     .retain(|p| p.x >= 0 && p.x < map.width && p.y >= 0 && p.y < map.height);
 
                 // if this is the player, reveal what they can see
-                if let Some(_p) = player.get(ent) {
+                if player.get(ent).is_some() {
                     for t in map.visible_tiles.iter_mut() {
                         *t = false
                     }
@@ -64,17 +64,18 @@ impl<'a> System<'a> for VisibilitySystem {
                         map.visible_tiles[idx] = true;
 
                         // Chance to reveal hidden things
-                        for e in map.tile_content[idx].iter() {
+                        spatial::for_each_tile_content(idx, |e| {
-                            if let Some(_maybe_hidden) = hidden.get(*e) {
+                            let maybe_hidden = hidden.get(e);
+                            if let Some(_maybe_hidden) = maybe_hidden {
                                 if rng.roll_dice(1, 24) == 1 {
-                                    if let Some(name) = names.get(*e) {
+                                    let name = names.get(e);
-                                        log.append(format!("You spotted a {}.", &name.name));
+                                    if let Some(name) = name {
-                                    }
+                                        log.entries.push(format!("You spotted a {}.", &name.name));
-
-                                    hidden.remove(*e);
                                     }
+                                    hidden.remove(e);
                                 }
                             }
+                        });
                     }
                 }
             }