playing with entity component system and mapping

src/main.rs

@@ -20,6 +20,12 @@ struct Renderable {
     bg: RGB,
 }
 
+#[derive(PartialEq, Copy, Clone)]
+enum TileType {
+    Wall,
+    Floor,
+}
+
 #[derive(Component)]
 struct LeftMover {}
 
@@ -60,6 +66,9 @@ impl GameState for State {
         player_input(self, ctx);
         self.systems.dispatch(&self.ecs);
 
+        let map = self.ecs.fetch::<Vec<TileType>>();
+        draw_map(&map, ctx);
+
         let positions = self.ecs.read_storage::<Position>();
         let renderables = self.ecs.read_storage::<Renderable>();
 
@@ -83,6 +92,8 @@ fn main() {
     gs.ecs.register::<LeftMover>();
     gs.ecs.register::<Player>();
 
+    gs.ecs.insert(new_map());
+
     gs.ecs
         .create_entity()
         .with(Position { x: 40, y: 25 })
@@ -147,3 +158,68 @@ fn player_input(gs: &mut State, ctx: &mut Rltk) {
         },
     }
 }
+
+fn xy_idx(x: i32, y: i32) -> usize {
+    (y as usize * 80) + x as usize
+}
+
+fn new_map() -> Vec<TileType> {
+    let mut map = vec![TileType::Floor; 80 * 50];
+
+    (0..80).into_iter().for_each(|x| {
+        map[xy_idx(x, 0)] = TileType::Wall;
+        map[xy_idx(x, 49)] = TileType::Wall;
+    });
+
+    (0..50).into_iter().for_each(|y| {
+        map[xy_idx(0, y)] = TileType::Wall;
+        map[xy_idx(79, y)] = TileType::Wall;
+    });
+
+    //rando-splat of walls
+    let mut rng = rltk::RandomNumberGenerator::new();
+
+    (0..400).into_iter().for_each(|_| {
+        let x = rng.roll_dice(1, 79);
+        let y = rng.roll_dice(1, 49);
+        let idx = xy_idx(x, y);
+        if idx != xy_idx(40, 25) {
+            map[idx] = TileType::Wall;
+        }
+    });
+
+    map
+}
+
+fn draw_map(map: &[TileType], ctx: &mut Rltk) {
+    let mut y = 0;
+    let mut x = 0;
+    map.iter().for_each(|tile| {
+        match tile {
+            TileType::Floor => {
+                ctx.set(
+                    x,
+                    y,
+                    RGB::from_f32(0.5, 0.5, 0.5),
+                    RGB::from_f32(0., 0., 0.),
+                    rltk::to_cp437('.'),
+                );
+            }
+            TileType::Wall => {
+                ctx.set(
+                    x,
+                    y,
+                    RGB::from_f32(0.0, 1.0, 0.0),
+                    RGB::from_f32(0., 0., 0.),
+                    rltk::to_cp437('#'),
+                );
+            }
+        }
+
+        x += 1;
+        if x > 79 {
+            x = 0;
+            y += 1;
+        }
+    });
+}