Add cellular automata

src/spawner.rs

@@ -6,7 +6,12 @@ use specs::saveload::{MarkedBuilder, SimpleMarker};
 
 use crate::random_table::RandomTable;
 use crate::rect::Rect;
-use crate::{AreaOfEffect, BlocksTile, CombatStats, Confusion, Consumable, DefenseBonus, EntryTrigger, EquipmentSlot, Equippable, Hidden, HungerClock, HungerState, InflictsDamage, Item, MagicMapper, MeleePowerBonus, Monster, Name, Player, Position, ProvidesFood, ProvidesHealing, Ranged, Renderable, SerializeMe, SingleActivation, Viewshed, MAP_WIDTH, MAX_MONSTER, Map, TileType};
+use crate::{
+    AreaOfEffect, BlocksTile, CombatStats, Confusion, Consumable, DefenseBonus, EntryTrigger,
+    EquipmentSlot, Equippable, Hidden, HungerClock, HungerState, InflictsDamage, Item, MagicMapper,
+    Map, MeleePowerBonus, Monster, Name, Player, Position, ProvidesFood, ProvidesHealing, Ranged,
+    Renderable, SerializeMe, SingleActivation, TileType, Viewshed, MAP_WIDTH, MAX_MONSTER,
+};
 
 pub fn player(ecs: &mut World, player_x: i32, player_y: i32) -> Entity {
     ecs.create_entity()
@@ -81,55 +86,78 @@ fn monster<S: ToString>(ecs: &mut World, x: i32, y: i32, glyph: FontCharType, na
 }
 
 #[allow(clippy::map_entry)]
-pub fn spawn_room(ecs: &mut World, room: &Rect, map_depth: i32, map: &Map) {
-    let spawn_table = room_table(map_depth);
-    let mut spawn_points: HashMap<usize, String> = HashMap::new();
+pub fn spawn_room(ecs: &mut World, room: &Rect, map_depth: i32) {
+    let mut possible_targets: Vec<usize> = Vec::new();
 
     {
-        let mut rng = ecs.write_resource::<RandomNumberGenerator>();
-        let num_spawns = rng.roll_dice(1, MAX_MONSTER + 3) + (map_depth - 1) - 3;
-
-        for _i in 0..num_spawns {
-            let mut added = false;
-            let mut tried = 0;
-            while !added && tried < 20 {
-                let x = (room.x1 + rng.roll_dice(1, i32::abs(room.x2 - room.x1))) as usize;
-                let y = (room.y1 + rng.roll_dice(1, i32::abs(room.y2 - room.y1))) as usize;
-                let idx = (y * MAP_WIDTH) + x;
-                if !spawn_points.contains_key(&idx) && map.tiles[idx] != TileType::Wall {
-                    spawn_points.insert(idx, spawn_table.roll(&mut rng));
-                    added = true;
-                } else {
-                    tried += 1;
+        let map = ecs.fetch::<Map>();
+        for y in room.y1 + 1..room.y2 {
+            for x in room.x1 + 1..room.x2 {
+                let idx = map.xy_idx(x, y);
+                if map.tiles[idx] == TileType::Floor {
+                    possible_targets.push(idx)
                 }
             }
         }
     }
 
-    for spawn in spawn_points.iter() {
-        let x = (*spawn.0 % MAP_WIDTH) as i32;
-        let y = (*spawn.0 / MAP_WIDTH) as i32;
+    spawn_region(ecs, &possible_targets, map_depth);
+}
 
-        match spawn.1.as_ref() {
-            "Goblin" => goblin(ecs, x, y),
-            "Orc" => orc(ecs, x, y),
-            "Health Potion" => health_potion(ecs, x, y),
-            "Fireball Scroll" => fireball_scroll(ecs, x, y),
-            "Confusion Scroll" => confusion_scroll(ecs, x, y),
-            "Magic Missile Scroll" => magic_missile_scroll(ecs, x, y),
-            "Dagger" => dagger(ecs, x, y),
-            "Longsword" => longsword(ecs, x, y),
-            "Shield" => shield(ecs, x, y),
-            "Tower Shield" => tower_shield(ecs, x, y),
-            "Helmet" => helmet(ecs, x, y),
-            "Breastplate" => breastplate(ecs, x, y),
-            "Leggings" => leggings(ecs, x, y),
-            "Sabatons" => sabatons(ecs, x, y),
-            "Rations" => rations(ecs, x, y),
-            "Magic Mapping Scroll" => magic_mapper_scroll(ecs, x, y),
-            "Bear Trap" => bear_trap(ecs, x, y),
-            _ => {}
-        }
+pub(crate) fn spawn_region(ecs: &mut World, area: &[usize], map_depth: i32) {
+    if let Some(spawn_points) = calculate_spawn_points(ecs, area, map_depth) {
+        spawn_entities(ecs, spawn_points)
+    }
+}
+
+fn spawn_entities(ecs: &mut World, spawn_points: HashMap<usize, String>) {
+    for spawn in spawn_points.iter() {
+        spawn_entity(ecs, &spawn);
+    }
+}
+
+fn calculate_spawn_points(ecs: &mut World, area: &[usize], map_depth: i32) -> Option<HashMap<usize, String>> {
+    let mut spawn_points: HashMap<usize, String> = HashMap::new();
+    let spawn_table = room_table(map_depth);
+    let mut areas: Vec<usize> = Vec::from(area);
+    let mut rng = ecs.write_resource::<RandomNumberGenerator>();
+
+    let num_spawns = i32::min(areas.len() as i32, rng.roll_dice(1, MAX_MONSTER + 3));
+    if num_spawns == 0 { return None; }
+
+    for _i in 0..num_spawns {
+        let array_idx = if areas.len() == 1 { 0usize } else { (rng.roll_dice(1, areas.len() as i32 - 1) as usize) };
+        let map_idx = areas[array_idx];
+        spawn_points.insert(map_idx, spawn_table.roll(&mut rng));
+        areas.remove(array_idx);
+    }
+
+    Some(spawn_points)
+}
+
+fn spawn_entity(ecs: &mut World, spawn: &(&usize, &String)) {
+    let x = (*spawn.0 % MAP_WIDTH) as i32;
+    let y = (*spawn.0 / MAP_WIDTH) as i32;
+
+    match spawn.1.as_ref() {
+        "Goblin" => goblin(ecs, x, y),
+        "Orc" => orc(ecs, x, y),
+        "Health Potion" => health_potion(ecs, x, y),
+        "Fireball Scroll" => fireball_scroll(ecs, x, y),
+        "Confusion Scroll" => confusion_scroll(ecs, x, y),
+        "Magic Missile Scroll" => magic_missile_scroll(ecs, x, y),
+        "Dagger" => dagger(ecs, x, y),
+        "Longsword" => longsword(ecs, x, y),
+        "Shield" => shield(ecs, x, y),
+        "Tower Shield" => tower_shield(ecs, x, y),
+        "Helmet" => helmet(ecs, x, y),
+        "Breastplate" => breastplate(ecs, x, y),
+        "Leggings" => leggings(ecs, x, y),
+        "Sabatons" => sabatons(ecs, x, y),
+        "Rations" => rations(ecs, x, y),
+        "Magic Mapping Scroll" => magic_mapper_scroll(ecs, x, y),
+        "Bear Trap" => bear_trap(ecs, x, y),
+        _ => {}
     }
 }