Add chapter 2.9

.idea/.gitignore

@@ -0,0 +1,8 @@
+# Default ignored files
+/shelf/
+/workspace.xml
+# Editor-based HTTP Client requests
+/httpRequests/
+# Datasource local storage ignored files
+/dataSources/
+/dataSources.local.xml

.idea/modules.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/.idea/roguelike.iml" filepath="$PROJECT_DIR$/.idea/roguelike.iml" />
+    </modules>
+  </component>
+</project>

.idea/roguelike.iml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="CPP_MODULE" version="4">
+  <component name="NewModuleRootManager">
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+      <excludeFolder url="file://$MODULE_DIR$/target" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>

.idea/vcs.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="$PROJECT_DIR$" vcs="Git" />
+  </component>
+</project>

src/components.rs

@@ -13,6 +13,7 @@ pub struct Renderable {
     pub glyph: rltk::FontCharType,
     pub fg: RGB,
     pub bg: RGB,
+    pub render_order: i32,
 }
 
 #[derive(Component, Debug)]
@@ -66,3 +67,34 @@ impl SufferDamage {
         }
     }
 }
+
+#[derive(Component, Debug)]
+pub struct Item {}
+
+#[derive(Component, Debug)]
+pub struct Potion {
+    pub heal_amount: i32,
+}
+
+#[derive(Component, Debug)]
+pub struct InBackpack {
+    pub owner: Entity,
+}
+
+#[derive(Component, Debug, Clone)]
+pub struct WantsToPickupItem {
+    pub collected_by: Entity,
+    pub item: Entity,
+}
+
+#[derive(Component, Debug, Clone)]
+pub struct WantsToDrinkPotion {
+    pub potion: Entity,
+}
+
+#[derive(Component, Debug, Clone)]
+pub struct WantsToDropItem {
+    pub item: Entity,
+}
+
+

src/gui.rs

@@ -1,13 +1,14 @@
+use rltk::{BTerm, Point, VirtualKeyCode};
+use rltk::RGB;
+use rltk::Rltk;
+use specs::prelude::*;
+
+use crate::{CombatStats, InBackpack, State};
 use crate::gamelog::GameLog;
-use crate::CombatStats;
 use crate::Map;
 use crate::Name;
 use crate::Player;
 use crate::Position;
-use rltk::Point;
-use rltk::Rltk;
-use rltk::RGB;
-use specs::prelude::*;
 
 pub fn draw_ui(ecs: &World, ctx: &mut Rltk) {
     ctx.draw_box(
@@ -150,3 +151,140 @@ fn draw_tooltips(ecs: &World, ctx: &mut Rltk) {
         }
     }
 }
+
+#[derive(PartialEq, Copy, Clone)]
+pub enum ItemMenuResult {
+    Cancel,
+    NoResponse,
+    Selected,
+}
+
+pub fn show_inventory(gs: &mut State, ctx: &mut Rltk) -> (ItemMenuResult, Option<Entity>) {
+    let player_entity = gs.ecs.fetch::<Entity>();
+    let names = gs.ecs.read_storage::<Name>();
+    let backpack = gs.ecs.read_storage::<InBackpack>();
+    let entities = gs.ecs.entities();
+
+    let inventory = (&backpack, &names)
+        .join()
+        .filter(|item| item.0.owner == *player_entity);
+    let count = inventory.count();
+
+    let mut y = (25 - (count / 2)) as i32;
+    ctx.draw_box(
+        15,
+        y - 2,
+        31,
+        (count + 3) as i32,
+        RGB::named(rltk::WHITE),
+        RGB::named(rltk::BLACK),
+    );
+    ctx.print_color(
+        18,
+        y - 2,
+        RGB::named(rltk::YELLOW),
+        RGB::named(rltk::BLACK),
+        "Inventory",
+    );
+    ctx.print_color(
+        18,
+        y + count as i32 + 1,
+        RGB::named(rltk::YELLOW),
+        RGB::named(rltk::BLACK),
+        "ESCAPE to cancel",
+    );
+
+    let mut equippable: Vec<Entity> = Vec::new();
+    let mut j = 0;
+    for (entity, _pack, name) in (&entities, &backpack, &names)
+        .join()
+        .filter(|item| item.1.owner == *player_entity)
+    {
+        ctx.set(
+            17,
+            y,
+            RGB::named(rltk::WHITE),
+            RGB::named(rltk::BLACK),
+            rltk::to_cp437('('),
+        );
+        ctx.set(
+            18,
+            y,
+            RGB::named(rltk::YELLOW),
+            RGB::named(rltk::BLACK),
+            97 + j as rltk::FontCharType,
+        );
+        ctx.set(
+            19,
+            y,
+            RGB::named(rltk::WHITE),
+            RGB::named(rltk::BLACK),
+            rltk::to_cp437(')'),
+        );
+
+        ctx.print(21, y, &name.name.to_string());
+        equippable.push(entity);
+        y += 1;
+        j += 1;
+    }
+
+    match ctx.key {
+        None => (ItemMenuResult::NoResponse, None),
+        Some(key) => {
+            match key {
+                VirtualKeyCode::Escape => { (ItemMenuResult::Cancel, None) }
+                _ => {
+                    let selection = rltk::letter_to_option(key);
+                    if selection > -1 && selection < count as i32 {
+                        return (ItemMenuResult::Selected, Some(equippable[selection as usize]));
+                    }
+                    (ItemMenuResult::NoResponse, None)
+                }
+            }
+        }
+    }
+}
+
+pub fn drop_item_menu(gs: &mut State, ctx: &mut Rltk) -> (ItemMenuResult, Option<Entity>) {
+    let player_entity = gs.ecs.fetch::<Entity>();
+    let names = gs.ecs.read_storage::<Name>();
+    let backpack = gs.ecs.read_storage::<InBackpack>();
+    let entities = gs.ecs.entities();
+
+    let inventory = (&backpack, &names).join().filter(|item| item.0.owner == *player_entity);
+    let count = inventory.count();
+
+    let mut y = (25 - (count / 2)) as i32;
+    ctx.draw_box(15, y - 2, 31, (count + 3) as i32, RGB::named(rltk::WHITE), RGB::named(rltk::BLACK));
+    ctx.print_color(18, y - 2, RGB::named(rltk::YELLOW), RGB::named(rltk::BLACK), "Drop Which Item?");
+    ctx.print_color(18, y + count as i32 + 1, RGB::named(rltk::YELLOW), RGB::named(rltk::BLACK), "ESCAPE to cancel");
+
+    let mut equippable: Vec<Entity> = Vec::new();
+    let mut j = 0;
+    for (entity, _pack, name) in (&entities, &backpack, &names).join().filter(|item| item.1.owner == *player_entity) {
+        ctx.set(17, y, RGB::named(rltk::WHITE), RGB::named(rltk::BLACK), rltk::to_cp437('('));
+        ctx.set(18, y, RGB::named(rltk::YELLOW), RGB::named(rltk::BLACK), 97 + j as rltk::FontCharType);
+        ctx.set(19, y, RGB::named(rltk::WHITE), RGB::named(rltk::BLACK), rltk::to_cp437(')'));
+
+        ctx.print(21, y, &name.name.to_string());
+        equippable.push(entity);
+        y += 1;
+        j += 1;
+    }
+
+    match ctx.key {
+        None => (ItemMenuResult::NoResponse, None),
+        Some(key) => {
+            match key {
+                VirtualKeyCode::Escape => { (ItemMenuResult::Cancel, None) }
+                _ => {
+                    let selection = rltk::letter_to_option(key);
+                    if selection > -1 && selection < count as i32 {
+                        return (ItemMenuResult::Selected, Some(equippable[selection as usize]));
+                    }
+                    (ItemMenuResult::NoResponse, None)
+                }
+            }
+        }
+    }
+}

src/inventory_system.rs

@@ -0,0 +1,116 @@
+use rltk::Rltk;
+use specs::prelude::*;
+
+use crate::{CombatStats, InBackpack, Name, Position, Potion, State, WantsToDrinkPotion, WantsToDropItem, WantsToPickupItem};
+use crate::gamelog::GameLog;
+use crate::gui::ItemMenuResult;
+
+pub struct ItemCollectionSystem {}
+
+impl<'a> System<'a> for ItemCollectionSystem {
+    type SystemData = (
+        ReadExpect<'a, Entity>,
+        WriteExpect<'a, GameLog>,
+        WriteStorage<'a, WantsToPickupItem>,
+        WriteStorage<'a, Position>,
+        ReadStorage<'a, Name>,
+        WriteStorage<'a, InBackpack>,
+    );
+
+    fn run(&mut self, data: Self::SystemData) {
+        let (player_entity, mut gamelog, mut wants_pickup, mut positions, names, mut backpack) =
+            data;
+
+        for pickup in wants_pickup.join() {
+            positions.remove(pickup.item);
+            backpack
+                .insert(
+                    pickup.item,
+                    InBackpack {
+                        owner: pickup.collected_by,
+                    },
+                )
+                .expect("Unable to insert backpack entry");
+
+            if pickup.collected_by == *player_entity {
+                gamelog.entries.push(format!(
+                    "You pick up the {}.",
+                    names.get(pickup.item).unwrap().name
+                ))
+            }
+        }
+
+        wants_pickup.clear();
+    }
+}
+
+pub struct PotionUseSystem {}
+
+impl<'a> System<'a> for PotionUseSystem {
+    type SystemData = (
+        ReadExpect<'a, Entity>,
+        WriteExpect<'a, GameLog>,
+        Entities<'a>,
+        WriteStorage<'a, WantsToDrinkPotion>,
+        ReadStorage<'a, Name>,
+        ReadStorage<'a, Potion>,
+        WriteStorage<'a, CombatStats>
+    );
+
+    fn run(&mut self, data: Self::SystemData) {
+        let (player_entity, mut gamelog, entities, mut wants_drink, names, potions, mut combat_stats) = data;
+
+        for (entity, drink, stats) in (&entities, &wants_drink, &mut combat_stats).join() {
+            let potion = potions.get(drink.potion);
+            match potion {
+                None => {}
+                Some(potion) => {
+                    stats.hp = i32::min(stats.max_hp, stats.hp + potion.heal_amount);
+                    if entity == *player_entity {
+                        gamelog.entries.push(format!("You drink the {}, healing {} hp.", names.get(drink.potion).unwrap().name, potion.heal_amount));
+                    }
+                    entities.delete(drink.potion).expect("Delete failed");
+                }
+            }
+        }
+
+        wants_drink.clear();
+    }
+}
+
+pub struct ItemDropSystem {}
+
+impl<'a> System<'a> for ItemDropSystem {
+    type SystemData = (
+        ReadExpect<'a, Entity>,
+        WriteExpect<'a, GameLog>,
+        Entities<'a>,
+        WriteStorage<'a, WantsToDropItem>,
+        ReadStorage<'a, Name>,
+        WriteStorage<'a, Position>,
+        WriteStorage<'a, InBackpack>
+    );
+
+    fn run(&mut self, data: Self::SystemData) {
+        let (player_entity, mut gamelog, entities, mut wants_drop, names, mut positions, mut backpack) = data;
+
+        for (entity, to_drop) in (&entities, &wants_drop).join() {
+            let mut dropper_pos: Position = Position { x: 0, y: 0 };
+            {
+                let dropped_pos = positions.get(entity).unwrap();
+                dropper_pos.x = dropped_pos.x;
+                dropper_pos.y = dropped_pos.y;
+            }
+            positions.insert(to_drop.item, Position { x: dropper_pos.x, y: dropper_pos.y }).expect("Unable to insert position");
+            backpack.remove(to_drop.item);
+
+            if entity == *player_entity {
+                gamelog.entries.push(format!("You drop the {}.", names.get(to_drop.item).unwrap().name));
+            }
+        }
+
+        wants_drop.clear();
+    }
+}
+
+

src/main.rs

@@ -1,3 +1,8 @@
+use std::thread::spawn;
+
+use rltk::{GameState, Point, RGB};
+use specs::prelude::*;
+
 use components::*;
 use damage_system::DamageSystem;
 use map::*;
@@ -5,21 +10,22 @@ use map_indexing_system::MapIndexingSystem;
 use melee_combat_system::MeleeCombatSystem;
 use monster_ai_system::*;
 use player::*;
-use rltk::{GameState, Point, RGB};
 use visibility_system::*;
 
-use specs::prelude::*;
+use crate::inventory_system::{ItemCollectionSystem, ItemDropSystem, PotionUseSystem};
 
 mod components;
 mod damage_system;
 mod gamelog;
 mod gui;
+mod inventory_system;
 mod map;
 mod map_indexing_system;
 mod melee_combat_system;
 mod monster_ai_system;
 mod player;
 mod rect;
+mod spawner;
 mod visibility_system;
 
 #[derive(PartialEq, Copy, Clone)]
@@ -28,6 +34,8 @@ pub enum RunState {
     PreRun,
     PlayerTurn,
     MonsterTurn,
+    ShowInventory,
+    ShowDropItem,
 }
 
 pub struct State {
@@ -51,6 +59,15 @@ impl State {
         let mut damagesystem = DamageSystem {};
         damagesystem.run_now(&self.ecs);
 
+        let mut inventory = ItemCollectionSystem {};
+        inventory.run_now(&self.ecs);
+
+        let mut potions = PotionUseSystem {};
+        potions.run_now(&self.ecs);
+
+        let mut drop_items = ItemDropSystem {};
+        drop_items.run_now(&self.ecs);
+
         self.ecs.maintain();
     }
 }
@@ -59,6 +76,25 @@ impl GameState for State {
     fn tick(&mut self, ctx: &mut rltk::Rltk) {
         ctx.cls();
 
+        {
+            draw_map(&self.ecs, ctx);
+
+            let positions = self.ecs.read_storage::<Position>();
+            let renderables = self.ecs.read_storage::<Renderable>();
+            let map = self.ecs.fetch::<Map>();
+
+            let mut data = (&positions, &renderables).join().collect::<Vec<_>>();
+            data.sort_by(|&a, &b| b.1.render_order.cmp(&a.1.render_order));
+            for (pos, render) in data.iter() {
+                let idx = map.xy_idx(pos.x, pos.y);
+                if map.visible_tiles[idx] {
+                    ctx.set(pos.x, pos.y, render.fg, render.bg, render.glyph)
+                }
+            }
+
+            gui::draw_ui(&self.ecs, ctx);
+        }
+
         let mut newrunstate;
         {
             let runstate = self.ecs.fetch::<RunState>();
@@ -79,6 +115,32 @@ impl GameState for State {
                 self.run_systems();
                 newrunstate = RunState::AwaitingInput;
             }
+            RunState::ShowInventory => {
+                let result = gui::show_inventory(self, ctx);
+                match result.0 {
+                    gui::ItemMenuResult::Cancel => newrunstate = RunState::AwaitingInput,
+                    gui::ItemMenuResult::NoResponse => {}
+                    gui::ItemMenuResult::Selected => {
+                        let item_entity = result.1.unwrap();
+                        let mut intent = self.ecs.write_storage::<WantsToDrinkPotion>();
+                        intent.insert(*self.ecs.fetch::<Entity>(), WantsToDrinkPotion { potion: item_entity }).expect("Unable to insert intent");
+                        newrunstate = RunState::PlayerTurn;
+                    }
+                }
+            }
+            RunState::ShowDropItem => {
+                let result = gui::drop_item_menu(self, ctx);
+                match result.0 {
+                    gui::ItemMenuResult::Cancel => newrunstate = RunState::AwaitingInput,
+                    gui::ItemMenuResult::NoResponse => {}
+                    gui::ItemMenuResult::Selected => {
+                        let item_entity = result.1.unwrap();
+                        let mut intent = self.ecs.write_storage::<WantsToDropItem>();
+                        intent.insert(*self.ecs.fetch::<Entity>(), WantsToDropItem { item: item_entity }).expect("Unable to insert intent");
+                        newrunstate = RunState::PlayerTurn;
+                    }
+                }
+            }
         }
 
         {
@@ -86,21 +148,6 @@ impl GameState for State {
             *runwriter = newrunstate;
         }
         damage_system::delete_the_dead(&mut self.ecs);
-
-        draw_map(&self.ecs, ctx);
-
-        let positions = self.ecs.read_storage::<Position>();
-        let renderables = self.ecs.read_storage::<Renderable>();
-        let map = self.ecs.fetch::<Map>();
-
-        for (pos, render) in (&positions, &renderables).join() {
-            let idx = map.xy_idx(pos.x, pos.y);
-            if map.visible_tiles[idx] {
-                ctx.set(pos.x, pos.y, render.fg, render.bg, render.glyph)
-            }
-        }
-
-        gui::draw_ui(&self.ecs, ctx);
     }
 }
 
@@ -115,6 +162,7 @@ fn main() -> rltk::BError {
     let mut gs = State { ecs: World::new() };
 
     gs.ecs.insert(RunState::PreRun);
+    gs.ecs.insert(rltk::RandomNumberGenerator::new());
     gs.ecs.insert(gamelog::GameLog {
         entries: vec!["Welcome to Rusty Roguelike".to_string()],
     });
@@ -129,83 +177,21 @@ fn main() -> rltk::BError {
     gs.ecs.register::<CombatStats>();
     gs.ecs.register::<WantsToMelee>();
     gs.ecs.register::<SufferDamage>();
+    gs.ecs.register::<Potion>();
+    gs.ecs.register::<Item>();
+    gs.ecs.register::<InBackpack>();
+    gs.ecs.register::<WantsToPickupItem>();
+    gs.ecs.register::<WantsToDrinkPotion>();
+    gs.ecs.register::<WantsToDropItem>();
     let map = Map::new_map_rooms_and_corridors();
+
     let (player_x, player_y) = map.rooms[0].center();
-
     gs.ecs.insert(Point::new(player_x, player_y));
-    let player_entity = gs
+    let player_entity = spawner::player(&mut gs.ecs, player_x, player_y);
-        .ecs
-        .create_entity()
-        .with(Position {
-            x: player_x,
-            y: player_y,
-        })
-        .with(Renderable {
-            glyph: rltk::to_cp437('@'),
-            fg: RGB::named(rltk::YELLOW),
-            bg: RGB::named(rltk::BLACK),
-        })
-        .with(Player {})
-        .with(Viewshed {
-            visible_tiles: Vec::new(),
-            range: 8,
-            dirty: true,
-        })
-        .with(Name {
-            name: "Player".to_string(),
-        })
-        .with(CombatStats {
-            max_hp: 30,
-            hp: 30,
-            defense: 2,
-            power: 5,
-        })
-        .build();
-
     gs.ecs.insert(player_entity);
 
-    let mut rng = rltk::RandomNumberGenerator::new();
+    for room in map.rooms.iter().skip(1) {
-    for (i, room) in map.rooms.iter().skip(1).enumerate() {
+        spawner::spawn_room(&mut gs.ecs, room);
-        let (x, y) = room.center();
-        let glyph: rltk::FontCharType;
-        let roll = rng.roll_dice(1, 2);
-        let name: String;
-        match roll {
-            1 => {
-                glyph = rltk::to_cp437('g');
-                name = "Goblin".to_string();
-            }
-            _ => {
-                glyph = rltk::to_cp437('o');
-                name = "Orc".to_string();
-            }
-        }
-
-        gs.ecs
-            .create_entity()
-            .with(Position { x, y })
-            .with(Renderable {
-                glyph,
-                fg: RGB::named(rltk::RED),
-                bg: RGB::named(rltk::BLACK),
-            })
-            .with(Viewshed {
-                visible_tiles: Vec::new(),
-                range: 8,
-                dirty: true,
-            })
-            .with(Monster {})
-            .with(Name {
-                name: format!("{} #{}", &name, i),
-            })
-            .with(BlocksTile {})
-            .with(CombatStats {
-                max_hp: 16,
-                hp: 16,
-                defense: 1,
-                power: 4,
-            })
-            .build();
     }
 
     gs.ecs.insert(map);

src/map.rs

@@ -11,9 +11,11 @@ pub enum TileType {
     Floor,
 }
 
-const MAP_WIDTH: usize = 80;
+pub const MAP_WIDTH: usize = 80;
-const MAP_HEIGHT: usize = 43;
+pub const MAP_HEIGHT: usize = 43;
-const MAP_COUNT: usize = MAP_HEIGHT * MAP_WIDTH;
+pub const MAP_COUNT: usize = MAP_HEIGHT * MAP_WIDTH;
+pub const MAX_MONSTER: i32 = 4;
+pub const MAX_ITEMS: i32 = 2;
 
 pub struct Map {
     pub tiles: Vec<TileType>,

src/player.rs

@@ -1,11 +1,14 @@
-use crate::{
+use std::cmp::{max, min};
-    components::{CombatStats, Player, Position, Viewshed, WantsToMelee},
+
-    map::{Map, TileType},
-    RunState, State,
-};
 use rltk::{console, Point, Rltk, VirtualKeyCode};
 use specs::prelude::*;
-use std::cmp::{max, min};
+
+use crate::{
+    components::{CombatStats, Player, Position, Viewshed, WantsToMelee},
+    Item,
+    map::{Map, TileType}, RunState, State, WantsToPickupItem,
+};
+use crate::gamelog::GameLog;
 
 pub fn try_move_player(delta_x: i32, delta_y: i32, ecs: &mut World) {
     let mut positions = ecs.write_storage::<Position>();
@@ -47,6 +50,40 @@ pub fn try_move_player(delta_x: i32, delta_y: i32, ecs: &mut World) {
     }
 }
 
+fn get_item(ecs: &mut World) {
+    let player_pos = ecs.fetch::<Point>();
+    let player_entity = ecs.fetch::<Entity>();
+    let entities = ecs.entities();
+    let items = ecs.read_storage::<Item>();
+    let positions = ecs.read_storage::<Position>();
+    let mut gamelog = ecs.fetch_mut::<GameLog>();
+
+    let mut target_item: Option<Entity> = None;
+    for (item_entity, _item, position) in (&entities, &items, &positions).join() {
+        if position.x == player_pos.x && position.y == player_pos.y {
+            target_item = Some(item_entity);
+        }
+    }
+
+    match target_item {
+        None => gamelog
+            .entries
+            .push("There is nothing here to pick up.".to_string()),
+        Some(item) => {
+            let mut pickup = ecs.write_storage::<WantsToPickupItem>();
+            pickup
+                .insert(
+                    *player_entity,
+                    WantsToPickupItem {
+                        collected_by: *player_entity,
+                        item,
+                    },
+                )
+                .expect("Unable to insert want to pickup");
+        }
+    }
+}
+
 pub fn player_input(gs: &mut State, ctx: &mut Rltk) -> RunState {
     match ctx.key {
         None => return RunState::AwaitingInput,
@@ -59,6 +96,9 @@ pub fn player_input(gs: &mut State, ctx: &mut Rltk) -> RunState {
             VirtualKeyCode::U => try_move_player(-1, -1, &mut gs.ecs),
             VirtualKeyCode::N => try_move_player(1, 1, &mut gs.ecs),
             VirtualKeyCode::B => try_move_player(-1, 1, &mut gs.ecs),
+            VirtualKeyCode::G => get_item(&mut gs.ecs),
+            VirtualKeyCode::I => return RunState::ShowInventory,
+            VirtualKeyCode::D => return RunState::ShowDropItem,
             _ => return RunState::AwaitingInput,
         },
     }

src/spawner.rs

@@ -0,0 +1,152 @@
+use rltk::{FontCharType, RandomNumberGenerator, RGB};
+use specs::prelude::*;
+
+use crate::{
+    BlocksTile, CombatStats, Item, MAP_WIDTH, MAX_ITEMS, MAX_MONSTER, Monster, Name, Player, Position,
+    Potion, Renderable, Viewshed,
+};
+use crate::rect::Rect;
+
+pub fn player(ecs: &mut World, player_x: i32, player_y: i32) -> Entity {
+    ecs.create_entity()
+        .with(Position {
+            x: player_x,
+            y: player_y,
+        })
+        .with(Renderable {
+            glyph: rltk::to_cp437('@'),
+            fg: RGB::named(rltk::YELLOW),
+            bg: RGB::named(rltk::BLACK),
+            render_order: 0,
+        })
+        .with(Player {})
+        .with(Viewshed {
+            visible_tiles: Vec::new(),
+            range: 8,
+            dirty: true,
+        })
+        .with(Name {
+            name: "Player".to_string(),
+        })
+        .with(CombatStats {
+            max_hp: 30,
+            hp: 30,
+            defense: 2,
+            power: 5,
+        })
+        .build()
+}
+
+pub fn random_monster(ecs: &mut World, x: i32, y: i32) {
+    let roll: i32;
+    {
+        let mut rng = ecs.write_resource::<RandomNumberGenerator>();
+        roll = rng.roll_dice(1, 2);
+    }
+    match roll {
+        1 => orc(ecs, x, y),
+        _ => goblin(ecs, x, y),
+    }
+}
+
+fn orc(ecs: &mut World, x: i32, y: i32) {
+    monster(ecs, x, y, rltk::to_cp437('o'), "Orc")
+}
+
+fn goblin(ecs: &mut World, x: i32, y: i32) {
+    monster(ecs, x, y, rltk::to_cp437('g'), "Goblin")
+}
+
+fn monster<S: ToString>(ecs: &mut World, x: i32, y: i32, glyph: FontCharType, name: S) {
+    ecs.create_entity()
+        .with(Position { x, y })
+        .with(Renderable {
+            glyph,
+            fg: RGB::named(rltk::RED),
+            bg: RGB::named(rltk::BLACK),
+            render_order: 1,
+        })
+        .with(Viewshed {
+            visible_tiles: Vec::new(),
+            range: 8,
+            dirty: true,
+        })
+        .with(Monster {})
+        .with(Name {
+            name: name.to_string(),
+        })
+        .with(BlocksTile {})
+        .with(CombatStats {
+            max_hp: 16,
+            hp: 16,
+            defense: 1,
+            power: 4,
+        })
+        .build();
+}
+
+pub fn spawn_room(ecs: &mut World, room: &Rect) {
+    let mut monster_spawn_points: Vec<usize> = Vec::new();
+    let mut item_spawn_points: Vec<usize> = Vec::new();
+
+    {
+        let mut rng = ecs.write_resource::<RandomNumberGenerator>();
+        let num_monsters = rng.roll_dice(1, MAX_MONSTER + 2) - 3;
+        let num_items = rng.roll_dice(1, MAX_ITEMS + 2) - 3;
+
+        for _i in 0..num_monsters {
+            let mut added = false;
+            while !added {
+                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 !monster_spawn_points.contains(&idx) {
+                    monster_spawn_points.push(idx);
+                    added = true;
+                }
+            }
+        }
+
+        for _i in 0..num_items {
+            let mut added = false;
+            while !added {
+                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 !item_spawn_points.contains(&idx) {
+                    item_spawn_points.push(idx);
+                    added = true;
+                }
+            }
+        }
+    }
+
+    for idx in monster_spawn_points.iter() {
+        let x = *idx % MAP_WIDTH;
+        let y = *idx / MAP_WIDTH;
+        random_monster(ecs, x as i32, y as i32);
+    }
+
+    for idx in item_spawn_points.iter() {
+        let x = *idx % MAP_WIDTH;
+        let y = *idx / MAP_WIDTH;
+        health_potion(ecs, x as i32, y as i32);
+    }
+}
+
+pub fn health_potion(ecs: &mut World, x: i32, y: i32) {
+    ecs.create_entity()
+        .with(Position { x, y })
+        .with(Renderable {
+            glyph: rltk::to_cp437('i'),
+            fg: RGB::named(rltk::MAGENTA),
+            bg: RGB::named(rltk::BLACK),
+            render_order: 2,
+        })
+        .with(Name {
+            name: "Health Potion".to_string(),
+        })
+        .with(Item {})
+        .with(Potion { heal_amount: 8 })
+        .build();
+}