refactor map into struct with impl trait

src/main.rs

@@ -35,12 +35,12 @@ pub struct Player {}
 fn try_move_player(delta_x: i32, delta_y: i32, ecs: &mut World) {
     let mut positions = ecs.write_storage::<Position>();
     let mut players = ecs.write_storage::<Player>();
-    let map = ecs.fetch::<Vec<TileType>>();
+    let map = ecs.fetch::<Map>();
 
     for (_player, pos) in (&mut players, &mut positions).join() {
         let x = min(79, max(0, pos.x + delta_x));
         let y = min(49, max(0, pos.y + delta_y));
-        if map[xy_idx(x, y)] != TileType::Wall {
+        if map.tile_at(x,y) != TileType::Wall {
             pos.x = x;
             pos.y = y;
         }
@@ -97,8 +97,8 @@ impl GameState for State {
         ctx.cls();
         self.run_systems();
         player_input(self, ctx);
-        let map = self.ecs.fetch::<Vec<TileType>>();
+        let map = self.ecs.fetch::<Map>();
-        draw_map(&map, ctx);
+        map.draw_map(ctx);
         let positions = self.ecs.read_storage::<Position>();
         let renderables = self.ecs.read_storage::<Renderable>();
 
@@ -114,8 +114,8 @@ fn main() {
         .with_title("Roguelike Tutorial")
         .build();
     let mut gs = State { ecs: World::new() };
-    let (rooms, map) = new_map_rooms_and_corridors();
+    let map = Map::new_map_rooms_and_corridors();
-    let (player_x, player_y) = rooms[0].center();
+    let (player_x, player_y) = map.rooms[0].center();
 
     gs.ecs.register::<Position>();
     gs.ecs.register::<Renderable>();
@@ -148,8 +148,6 @@ fn main() {
             .with(LeftMover {})
             .build();
     }
-
-    gs.ecs.insert(rooms);
     gs.ecs.insert(map);
 
     rltk::main_loop(context, gs);

src/map.rs

@@ -8,34 +8,53 @@ pub enum TileType {
     Floor,
 }
 
-pub fn xy_idx(x: i32, y: i32) -> usize {
+pub struct Map {
-    (y as usize * 80) + x as usize
+    pub tiles: Vec<TileType>,
+    pub rooms: Vec<Rect>,
+    pub width: i32,
+    pub height: i32,
 }
 
-fn apply_room_to_map(room: &Rect, map: &mut Vec<TileType>) {
+impl Map {
+    pub fn xy_idx(&self, x: i32, y: i32) -> usize {
+        ((y * self.width) + x) as usize
+    }
+
+    pub fn tile_at(&self, x: i32, y:i32) -> TileType {
+        self.tiles[self.xy_idx(x, y)]
+    }
+
+    fn apply_room_to_map(&mut self, room: &Rect) {
         for x in room.x1..room.x2 {
             for y in room.y1..room.y2 {
-            map[xy_idx(x, y)] = TileType::Floor
+                let idx = self.xy_idx(x,y);
+                self.tiles[idx] = TileType::Floor
             }
         }
     }
 
-fn apply_horizontal_tunnel(map: &mut Vec<TileType>, x1: i32, x2: i32, y: i32) {
+    fn apply_horizontal_tunnel(&mut self, x1: i32, x2: i32, y: i32) {
         for x in min(x1, x2)..=max(x1, x2) {
-        map[xy_idx(x, y)] = TileType::Floor
+            let idx=self.xy_idx(x, y);
+            self.tiles[idx] = TileType::Floor
         }
     }
 
-fn apply_vertical_tunnel(map: &mut Vec<TileType>, x: i32, y1: i32, y2: i32) {
+    fn apply_vertical_tunnel(&mut self, x: i32, y1: i32, y2: i32) {
         for y in min(y1, y2)..=max(y1, y2) {
-        map[xy_idx(x, y)] = TileType::Floor
+            let idx=self.xy_idx(x, y);
+            self.tiles[idx] = TileType::Floor
         }
     }
 
-pub fn new_map_rooms_and_corridors() -> (Vec<Rect>,Vec<TileType>) {
+    pub fn new_map_rooms_and_corridors() -> Map {
-    let mut map = vec![TileType::Wall; 80 * 50];
+        let mut map = Map {
+            tiles: vec![TileType::Wall; 80 * 50],
+            rooms: Vec::new(),
+            width: 80,
+            height: 50,
+        };
 
-    let mut rooms: Vec<Rect> = Vec::new();
         const MAX_ROOMS: i32 = 30;
         const MIN_SIZE: i32 = 6;
         const MAX_SIZE: i32 = 10;
@@ -49,45 +68,43 @@ pub fn new_map_rooms_and_corridors() -> (Vec<Rect>,Vec<TileType>) {
             let y = rng.roll_dice(1, 50 - h - 1) - 1;
             let new_room = Rect::new(x, y, w, h);
             let mut ok = true;
-        for other_room in rooms.iter() {
+            for other_room in map.rooms.iter() {
                 if new_room.intersect(other_room) {
                     ok = false
                 }
             }
             if ok {
-            apply_room_to_map(&new_room, &mut map);
+                map.apply_room_to_map(&new_room);
-            if rooms.len() > 0 {
+                if map.rooms.len() > 0 {
                     let r1_center = new_room.center();
-                let r2_center = rooms[rooms.len() - 1].center();
+                    let r2_center = map.rooms[map.rooms.len() - 1].center();
                     if rng.range(0, 2) == 1 {
-                    apply_horizontal_tunnel(&mut map, r1_center.0, r2_center.0, r1_center.1);
+                        map.apply_horizontal_tunnel(r1_center.0, r2_center.0, r1_center.1);
-                    apply_vertical_tunnel(
+                        map.apply_vertical_tunnel(
-                        &mut map,
                             max(r1_center.0, r2_center.0),
                             r1_center.1,
                             r2_center.1,
                         );
                     } else {
-                    apply_vertical_tunnel(&mut map, r1_center.0, r1_center.1, r2_center.1);
+                        map.apply_vertical_tunnel(r1_center.0, r1_center.1, r2_center.1);
-                    apply_horizontal_tunnel(
+                        map.apply_horizontal_tunnel(
-                        &mut map,
                             r1_center.0,
                             r2_center.0,
                             max(r1_center.1, r2_center.1),
                         );
                     }
                 }
-            rooms.push(new_room);
+                map.rooms.push(new_room);
             }
         }
 
-    (rooms,map)
+        map
     }
 
-pub fn draw_map(map: &[TileType], ctx: &mut Rltk) {
+    pub fn draw_map(&self, ctx: &mut Rltk) {
         let mut y = 0;
         let mut x = 0;
-    for tile in map.iter() {
+        for tile in self.tiles.iter() {
             // Render a tile depending upon the tile type
             match tile {
                 TileType::Floor => {
@@ -118,3 +135,4 @@ pub fn draw_map(map: &[TileType], ctx: &mut Rltk) {
             }
         }
     }
+}