Clean up

samples/flappy-bird/src/main.rs

@@ -1,6 +1,6 @@
 //! A simple example of a Flappy Bird game using surreal and hecs.
 
-use hecs::{EntityBuilder, World};
+use hecs::World;
 use surreal::{
   backends::sdl::{Window, WindowSettings},
   common::{DeltaClock, StringName},
@@ -18,9 +18,11 @@ fn main() {
   .unwrap();
 
   let graphics = GraphicsEngine::opengl(&window);
+  let mut queue = RenderQueue::new();
 
   let mut game = Game::new();
-  let mut queue = RenderQueue::new();
+
+  game.initialize();
 
   while window.update() {
     game.update();
@@ -35,7 +37,6 @@ fn main() {
 struct Game {
   world: World,
   clock: DeltaClock,
-  sprite_cache: SpriteCache,
 }
 
 struct Position {
@@ -53,46 +54,72 @@ struct Sprite {
   tint: Color32,
 }
 
-struct SpriteCache {}
+struct Player {}
+
+struct Obstacle {}
 
 impl Game {
   pub fn new() -> Self {
-    let mut world = World::new();
-
-    // create entities
-    for _ in 0..10 {
-      let mut builder = EntityBuilder::default();
-
-      builder.add(Position { x: 0.0, y: 0.0 });
-      builder.add(Velocity { x: 1.0, y: 1.0 });
-      builder.add(Sprite {
-        texture: "bird".into(),
-        tint: Color32::WHITE,
-      });
-
-      world.spawn(builder.build());
-    }
-
     Self {
-      world,
+      world: World::new(),
       clock: DeltaClock::new(),
-      sprite_cache: SpriteCache {},
     }
   }
 
+  pub fn initialize(&mut self) {
+    // spawn the player
+    self.world.spawn((
+      Position { x: 0.0, y: 0.0 },
+      Velocity { x: 0.0, y: 0.0 },
+      Sprite {
+        texture: "sprites/player.png".into(),
+        tint: Color32::WHITE,
+      },
+      Player {},
+    ));
+
+    // spawn the first obstacle
+    self.world.spawn((
+      Position { x: 0.0, y: 0.0 },
+      Sprite {
+        texture: "sprites/obstacle.png".into(),
+        tint: Color32::WHITE,
+      },
+      Obstacle {},
+    ));
+  }
+
   pub fn update(&mut self) {
     let delta_time = self.clock.tick();
 
-    // update positions
+    self.update_physics(delta_time);
+    self.update_player();
+  }
+
+  fn update_physics(&mut self, delta_time: f32) {
+    const GRAVITY: f32 = 9.8;
+
     for (_, (position, velocity)) in self.world.query_mut::<(&mut Position, &mut Velocity)>() {
       position.x += velocity.x * delta_time;
       position.y += velocity.y * delta_time;
+
+      velocity.y += GRAVITY * delta_time;
+    }
+  }
+
+  fn update_player(&mut self) {
+    for (_, (_velocity, _player)) in self.world.query_mut::<(&mut Velocity, &Player)>() {
+      // TODO: player input
     }
   }
 
   pub fn draw(&self, queue: &mut RenderQueue) {
     queue.clear_color_buffer(Color::BLACK);
 
+    self.draw_sprites(queue);
+  }
+
+  fn draw_sprites(&self, _queue: &mut RenderQueue) {
     for (_, (_position, _sprite)) in &mut self.world.query::<(&Position, &Sprite)>() {
       // queue
     }