Log state transitions

tetris/src/debug.rs

@@ -3,11 +3,38 @@ use super::*;
 /// Debug UI for Tetris
 /// Some overlap with more general purpose debug tools,
 /// but built one-off because of the changse to UI in Bevy 0.17
+pub struct DebugPlugin;
 
-struct DebugPlugin;
-
+// Debugging wish-list:
+// - Toggle debug on/off with f12 key
+// - Bounding boxes around entities
+// - Cursor at the center of the world
+// - Show current state(s)
 impl Plugin for DebugPlugin {
     fn build(&self, app: &mut App) {
-        app;
+        app.add_systems(Update, (
+            log_transition::<Debugger>.run_if(state_changed::<Debugger>),
+            log_transition::<Loading>.run_if(state_changed::<Loading>),
+            log_transition::<GameState>.run_if(state_changed::<GameState>),
+        ));
     }
 }
+
+/// Tracks if the game is in debug mode
+#[derive(States, Default, Clone, Eq, Debug, PartialEq, Hash)]
+pub enum Debugger {
+    #[default]
+    Off,
+    On,
+}
+
+fn log_transition<T: States + PartialEq + Clone>(
+    curr: Res<State<T>>,
+    mut prev: Local<Option<T>>,
+) {
+    debug_assert!(Some(curr.get().clone()) != *prev);
+
+    info!("State Change:: {:?} -> {:?}", *prev, *curr);
+
+    *prev = Some(curr.get().clone());
+}

tetris/src/main.rs

@@ -12,7 +12,7 @@ use fighter::*;
 
 fn main() {
     App::new()
-        .add_plugins((DefaultPlugins, BlocksPlugin, FighterPlugin))
+        .add_plugins((DefaultPlugins, BlocksPlugin, FighterPlugin, DebugPlugin))
         .init_state::<Loading>()
         .init_state::<Debugger>()
         .init_state::<GameState>()
@@ -42,14 +42,6 @@ enum Loading {
     Idle,
 }
 
-/// Tracks if the game is in debug mode
-#[derive(States, Default, Clone, Eq, Debug, PartialEq, Hash)]
-enum Debugger {
-    #[default]
-    Off,
-    On,
-}
-
 /// Tracks what state the main game loop is in
 #[derive(States, Default, Clone, Eq, Debug, PartialEq, Hash)]
 enum GameState {
@@ -71,6 +63,12 @@ struct SetupChecklist {
     spawn_shape: bool,
 }
 
+impl SetupChecklist {
+    fn done(&self) -> bool {
+        self.spawn_shape
+    }
+}
+
 /// Sends the game into Loading::Active if assets are added to the AllAssets list
 fn loading_check(mut next: ResMut<NextState<Loading>>, all_assets: Res<AllAssets>) {
     debug_assert!(all_assets.is_changed());
@@ -102,6 +100,7 @@ fn setup_game(curr: Res<State<GameState>>, mut next: ResMut<NextState<GameState>
     next.set(GameState::Setup);
 }
 
+/// Wait until all checklist items are complete
 fn setup_wait(
     curr: Res<State<GameState>>,
     mut next: ResMut<NextState<GameState>>,
@@ -110,7 +109,7 @@ fn setup_wait(
     debug_assert!(*curr.get() == GameState::Setup);
 
     // If all checks pass, move on to the run state
-    if checklist.spawn_shape {
+    if checklist.done() {
         next.set(GameState::Run);
     }
 }