Basically done?

src/main.rs

@@ -2,7 +2,16 @@
 #![feature(stmt_expr_attributes)]
 
 use bracket_lib::prelude::*;
+use std::collections::VecDeque;
 
+const SCREEN_WIDTH: u16 = 80;
+const SCREEN_HEIGHT: u16 = 50;
+const FRAME_DURATION: f32 = 20.0;
+
+const X_OFFSET: i32 = 10;
+const Y_START: i32 = 25;
+
+#[derive(Debug)]
 struct Obstacle {
     x: i32,
     gap_y: u16,
@@ -12,6 +21,7 @@ struct Obstacle {
 impl Obstacle {
     fn new(x: i32, score: u32) -> Self {
         let mut random = RandomNumberGenerator::new();
+        // TODO: make smaller with score
         Obstacle {
             x,
             gap_y: random.range(10, 40),
@@ -19,6 +29,22 @@ impl Obstacle {
             gap_height: u16::max(2, 15),
         }
     }
+
+    fn render(&mut self, ctx: &mut BTerm, current_x: i32) {
+        let x = self.x - current_x + X_OFFSET;
+        let (y_top_of_bottom, y_bottom_of_top) = self.y_bounds();
+        let y_positions = [0..y_bottom_of_top, y_top_of_bottom..SCREEN_HEIGHT]
+                .map(|r| { r.collect::<Vec<u16>>() })
+                .concat();
+        for y in y_positions { ctx.set(x, y as i32, RED, BLACK, to_cp437('|')); }
+    }
+
+    fn y_bounds(&mut self) -> (u16, u16) {
+        let half_gap_height = self.gap_height / 2;
+        let y_bottom_of_top = self.gap_y - half_gap_height;
+        let y_top_of_bottom = self.gap_y + half_gap_height;
+        (y_top_of_bottom, y_bottom_of_top)
+    }
 }
 
 struct Player {
@@ -27,13 +53,6 @@ struct Player {
     velocity: f32,
 }
 
-// const SCREEN_WIDTH: u16 = 80;
-const SCREEN_HEIGHT: u16 = 50;
-const FRAME_DURATION: f32 = 20.0;
-
-const X_OFFSET: i32 = 10;
-const Y_START: i32 = 25;
-
 impl Player {
     fn new(y: i32) -> Self {
         Player {
@@ -69,6 +88,8 @@ struct State {
     player: Player,
     time: f32,
     mode: GameMode,
+    obstacles: VecDeque<Obstacle>,
+    obstacleSpawnTime: f32,
     score: u32,
 }
 
@@ -84,6 +105,8 @@ impl State {
             player: Player::new(Y_START),
             time: 0.0,
             mode: GameMode::Menu,
+            obstacles: VecDeque::new(),
+            obstacleSpawnTime: 0.0,
             score: 0u32,
         }
     }
@@ -107,13 +130,19 @@ impl State {
         self.player = Player::new(25);
         self.time = 0.0;
         self.mode = GameMode::Playing;
+        self.obstacles = VecDeque::new();
+        self.score = 0u32;
     }
 
     fn play(&mut self, ctx: &mut BTerm) {
         ctx.cls_bg(BLACK);
         self.time += ctx.frame_time_ms;
+        self.obstacleSpawnTime -= ctx.frame_time_ms;
 
-        ctx.print(1, 1, "Playing...");
+        ctx.print(1, 1, "Press Space to flag!");
+        ctx.print(1, 2, &format!("Score: {}", self.score));
+        ctx.print(1, 3, &format!("Pos: {}, {}", self.player.x, self.player.y));
+        ctx.print(1, 4, &format!("Obstables: (Spawn: {}) #{} {:#?}", self.obstacleSpawnTime, self.obstacles.len(), self.obstacles));
 
         // update
         if self.time > FRAME_DURATION {
@@ -121,13 +150,37 @@ impl State {
             self.time %= FRAME_DURATION;
         }
 
+        if self.obstacleSpawnTime < 0.0 {
+            let mut random = RandomNumberGenerator::new();
+            self.obstacleSpawnTime += random.range(400.0, 1200.0);
+            let o = Obstacle::new(self.player.x + SCREEN_WIDTH as i32, self.score);
+            self.obstacles.push_back(o);
+        }
+
+        if let Some(o) = self.obstacles.front() {
+            if o.x < self.player.x - X_OFFSET {
+                self.obstacles.pop_front();
+                self.score += 1;
+            }
+        }
+
         if let Some(VirtualKeyCode::Space) = ctx.key {
             self.player.flap();
         }
 
         self.player.render(ctx);
+        let mut did_collide = false;
+        self.obstacles.iter_mut().for_each(|o| {
+            if o.x == self.player.x {
+                let (y_top_of_bottom, y_bottom_of_top) = o.y_bounds();
+                if (self.player.y as u16) >= y_top_of_bottom || (self.player.y as u16) <= y_bottom_of_top {
+                    did_collide = true;
+                }
+            }
+            o.render(ctx, self.player.x);
+        });
 
-        if self.player.y > SCREEN_HEIGHT as i32 {
+        if did_collide || self.player.y > (SCREEN_HEIGHT as i32) {
             self.die();
         }
         // self.mode = GameMode::Dead;
@@ -140,6 +193,7 @@ impl State {
     fn dead(&mut self, ctx: &mut BTerm) {
         ctx.cls();
         ctx.print_centered(5, "You are dead. =(");
+        ctx.print_centered(6, &format!("Final Score: {}", self.score));
         ctx.print_centered(8, "(P) Play Again");
         ctx.print_centered(9, "(Q) Quit");