add system log to hud

src/hud.rs

@@ -1,15 +1,18 @@
 use crate::{settings, actor};
 use bevy::prelude::*;
 use bevy::diagnostic::{DiagnosticsStore, FrameTimeDiagnosticsPlugin};
+use std::collections::VecDeque;
 
 const HUD_REFRESH_TIME: f32 = 0.5;
 const FONT: &str = "tmp/fonts/NotoSansSC-Thin.ttf";
+const LOG_MAX: usize = 5;
 
 pub struct HudPlugin;
 impl Plugin for HudPlugin {
     fn build(&self, app: &mut App) {
         app.add_systems(Startup, setup);
         app.add_systems(Update, (update, handle_input));
+        app.insert_resource(Log { logs: VecDeque::with_capacity(LOG_MAX) });
         app.insert_resource(FPSUpdateTimer(
                 Timer::from_seconds(HUD_REFRESH_TIME, TimerMode::Repeating)));
     }
@@ -21,11 +24,28 @@ struct GaugesText;
 #[derive(Resource)]
 struct FPSUpdateTimer(Timer);
 
+#[derive(Resource)]
+struct Log {
+    logs: VecDeque<String>,
+}
+
+impl Log {
+    pub fn add(&mut self, message: String) {
+        if self.logs.len() == LOG_MAX {
+            self.logs.pop_front();
+        }
+        self.logs.push_back(message);
+    }
+}
+
 fn setup(
     mut commands: Commands,
     settings: Res<settings::Settings>,
     asset_server: Res<AssetServer>,
+    mut log: ResMut<Log>,
 ) {
+    log.add("Customer wake-up registered.".to_string());
+    log.add("Systems reactivated.".to_string());
     let visibility = if settings.hud_active {
         Visibility::Inherited
     } else {
@@ -104,6 +124,24 @@ fn setup(
                 ..default()
             }
         ),
+        TextSection::new(
+            "\n\n",
+            TextStyle {
+                font: asset_server.load(FONT),
+                font_size: settings.font_size_hud,
+                color: Color::GRAY,
+                ..default()
+            }
+        ),
+        TextSection::new(
+            "<log>",
+            TextStyle {
+                font: asset_server.load(FONT),
+                font_size: settings.font_size_hud,
+                color: Color::GRAY,
+                ..default()
+            }
+        ),
     ]);
     bundle_fps.visibility = visibility;
     commands.spawn((
@@ -115,6 +153,7 @@ fn setup(
 fn update(
     diagnostics: Res<DiagnosticsStore>,
     time: Res<Time>,
+    log: Res<Log>,
     player: Query<(&actor::Suit, &actor::LifeForm), With<actor::Player>>,
     mut timer: ResMut<FPSUpdateTimer>,
     mut query: Query<&mut Text, With<GaugesText>>,
@@ -139,6 +178,10 @@ fn update(
                 text.sections[7].value = format!("{adrenaline:.0}pg/mL");
             }
         }
+        for mut text in &mut query {
+            let logs_vec: Vec<&str> = log.logs.iter().map(|s| s.as_str()).collect();
+            text.sections[9].value = logs_vec.join("\n");
+        }
     }
 }