Saving and loading

src/main.rs

@@ -697,7 +697,11 @@ fn menu<T: AsRef<str>>(header: &str, options: &[T], width: i32, root: &mut Root)
   );
 
   // Calculate total height for the header (after auto-wrap) and one line per option
-  let header_height = root.get_height_rect(0, 0, width, SCREEN_HEIGHT, header);
+  let header_height = if header.is_empty() {
+    0
+  } else {
+    root.get_height_rect(0, 0, width, SCREEN_HEIGHT, header)
+  };
   let height = options.len() as i32 + header_height;
 
   // Create an off-screen console that represents the menu's window
@@ -1191,25 +1195,21 @@ fn render_all(tcod: &mut Tcod, game: &mut Game, objects: &[Object], fov_recomput
   );
 }
 
-fn main() {
-  tcod::system::set_fps(FPS);
-
-  let root = Root::initializer()
-    .font("arial10x10.png", FontLayout::Tcod)
-    .font_type(FontType::Greyscale)
-    .size(SCREEN_WIDTH, SCREEN_HEIGHT)
-    .title("Rust/libtcod tutorial")
-    .init();
-
-  let mut tcod = Tcod {
-    root,
-    con: Offscreen::new(MAP_WIDTH, MAP_HEIGHT),
-    panel: Offscreen::new(SCREEN_WIDTH, PANEL_HEIGHT),
-    fov: FovMap::new(MAP_WIDTH, MAP_HEIGHT),
-    key: Default::default(),
-    mouse: Default::default(),
-  };
+fn initialise_fov(tcod: &mut Tcod, map: &Map) {
+  // Populate FOV map, according to generated map
+  for y in 0..MAP_HEIGHT {
+    for x in 0..MAP_WIDTH {
+      tcod.fov.set(
+        x,
+        y,
+        !map[x as usize][y as usize].block_sight,
+        !map[x as usize][y as usize].blocked,
+      )
+    }
+  }
+}
 
+fn new_game(tcod: &mut Tcod) -> (Game, Vec<Object>) {
   // Create player object
   let mut player = Object::new(0, 0, '@', "player", WHITE, true);
   player.alive = true;
@@ -1231,19 +1231,7 @@ fn main() {
     inventory: vec![],
   };
 
-  // Populate FOV map, according to generated map
-  for y in 0..MAP_HEIGHT {
-    for x in 0..MAP_WIDTH {
-      tcod.fov.set(
-        x,
-        y,
-        !game.map[x as usize][y as usize].block_sight,
-        !game.map[x as usize][y as usize].blocked,
-      )
-    }
-  }
-
-  let mut previous_player_position = (-1, -1);
+  initialise_fov(tcod, &game.map);
 
   // A warm welcoming message!
   game.messages.add(
@@ -1251,21 +1239,33 @@ fn main() {
     RED,
   );
 
+  (game, objects)
+}
+
+fn play_game(tcod: &mut Tcod, game: &mut Game, objects: &mut Vec<Object>) {
+  // force FOV "recompute" first time through the game loop
+  let mut previous_player_position = (-1, -1);
+
   // Main game loop
   while !tcod.root.window_closed() {
+    // clear the screen of the previous frame
+    tcod.con.clear();
+
     match input::check_for_event(input::MOUSE | input::KEY_PRESS) {
       Some((_, Event::Mouse(m))) => tcod.mouse = m,
       Some((_, Event::Key(k))) => tcod.key = k,
       _ => tcod.key = Default::default(),
     }
 
-    tcod.con.clear();
+    // Render the screen
     let fov_recompute = previous_player_position != (objects[PLAYER].pos());
-    render_all(&mut tcod, &mut game, &objects, fov_recompute);
+    render_all(tcod, game, &objects, fov_recompute);
+
     tcod.root.flush();
 
+    // Handle keys and exit game if needed
     previous_player_position = objects[PLAYER].pos();
-    let player_action = handle_keys(&mut tcod, &mut game, &mut objects);
+    let player_action = handle_keys(tcod, game, objects);
     if player_action == PlayerAction::Exit {
       break;
     }
@@ -1274,9 +1274,75 @@ fn main() {
     if objects[PLAYER].alive && player_action != PlayerAction::DidntTakeTurn {
       for id in 0..objects.len() {
         if objects[id].ai.is_some() {
-          ai_take_turn(id, &tcod, &mut game, &mut objects);
+          ai_take_turn(id, tcod, game, objects);
         }
       }
     }
   }
 }
+
+fn main_menu(tcod: &mut Tcod) {
+  let img = tcod::image::Image::from_file("menu_background.png")
+    .ok()
+    .expect("Background image not found");
+
+  while !tcod.root.window_closed() {
+    // Show the background image, at twice the regular console resolution
+    tcod::image::blit_2x(&img, (0, 0), (-1, -1), &mut tcod.root, (0, 0));
+
+    tcod.root.set_default_foreground(LIGHT_YELLOW);
+    tcod.root.print_ex(
+      SCREEN_WIDTH / 2,
+      SCREEN_HEIGHT / 2 - 4,
+      BackgroundFlag::None,
+      TextAlignment::Center,
+      "TOMB OF DOOM",
+    );
+    tcod.root.print_ex(
+      SCREEN_WIDTH / 2,
+      SCREEN_HEIGHT - 2,
+      BackgroundFlag::None,
+      TextAlignment::Center,
+      "By m",
+    );
+
+    // Show options and wait for the player's choice
+    let choices = &["Play a new game", "Continue last game", "Quit"];
+    let choice = menu("", choices, 24, &mut tcod.root);
+
+    match choice {
+      Some(0) => {
+        // New game
+        let (mut game, mut objects) = new_game(tcod);
+        play_game(tcod, &mut game, &mut objects);
+      }
+      Some(2) => {
+        // Quit
+        break;
+      }
+      _ => {}
+    }
+  }
+}
+
+fn main() {
+  tcod::system::set_fps(FPS);
+
+  let root = Root::initializer()
+    .font("arial10x10.png", FontLayout::Tcod)
+    .font_type(FontType::Greyscale)
+    .size(SCREEN_WIDTH, SCREEN_HEIGHT)
+    .title("Rust/libtcod tutorial")
+    .init();
+
+  let mut tcod = Tcod {
+    root,
+    con: Offscreen::new(MAP_WIDTH, MAP_HEIGHT),
+    panel: Offscreen::new(SCREEN_WIDTH, PANEL_HEIGHT),
+    fov: FovMap::new(MAP_WIDTH, MAP_HEIGHT),
+    key: Default::default(),
+    mouse: Default::default(),
+  };
+
+  main_menu(&mut tcod);
+}