add orbital clock (in menu)

src/cmd.rs

@@ -18,6 +18,7 @@ use bevy_xpbd_3d::prelude::*;
 use regex::Regex;
 
 pub const ID_SPECIAL_PLAYERCAM: &str = "PLAYERCAMERA";
+pub const ID_PLAYER: &str = "player";
 pub const ID_EARTH: &str = "earth";
 pub const ID_SOL: &str = "sol";
 pub const ID_JUPITER: &str = "jupiter";

src/menu.rs

@@ -49,6 +49,8 @@ pub struct MenuElement;
 #[derive(Component)]
 pub struct MenuTopLevel;
 #[derive(Component)]
+pub struct FooterElement;
+#[derive(Component)]
 pub struct MenuAchievements;
 #[derive(Component)]
 pub struct DeathScreenElement;
@@ -349,7 +351,9 @@ pub fn setup(
             },
         ))
         .with_children(|builder| {
-            builder.spawn((TextBundle {
+            builder.spawn((
+                FooterElement,
+                TextBundle {
                     text: Text {
                         sections: vec![TextSection::new(
                             format!("{} {}", GAME_NAME, settings.version.as_str()),
@@ -359,7 +363,8 @@ pub fn setup(
                         ..default()
                     },
                     ..default()
-            },));
+                },
+            ));
         });
 }
 
@@ -435,8 +440,17 @@ pub struct MenuState {
 
 pub fn update_menu(
     mut q_text: Query<&mut Text, With<MenuTopLevel>>,
-    mut q_achievement_text: Query<&mut Text, (With<MenuAchievements>, Without<MenuTopLevel>)>,
+    mut q_footer: Query<&mut Text, (With<FooterElement>, Without<MenuTopLevel>)>,
+    mut q_achievement_text: Query<
+        &mut Text,
+        (
+            With<MenuAchievements>,
+            Without<MenuTopLevel>,
+            Without<FooterElement>,
+        ),
+    >,
     mut q_vis: Query<&mut Visibility, With<menu::MenuElement>>,
+    id2pos: Res<game::Id2Pos>,
     achievement_tracker: Res<var::AchievementTracker>,
     menustate: Res<MenuState>,
     settings: Res<Settings>,
@@ -451,6 +465,21 @@ pub fn update_menu(
 
     let bools = achievement_tracker.to_bool_vec();
     let rendered = achievement_tracker.to_textsections();
+    if let (Ok(mut text), Some(player_pos), Some(jupiter_pos)) = (
+        q_footer.get_single_mut(),
+        id2pos.0.get(cmd::ID_PLAYER),
+        id2pos.0.get(cmd::ID_JUPITER),
+    ) {
+        let (clock_max, clock_current) =
+            nature::pos_to_orbit_time(*player_pos, *jupiter_pos, nature::JUPITER_MASS);
+        text.sections[0].value = format!(
+            "Orbital Clock:\n{} of {}\n{} {}",
+            nature::format_seconds_to_hour_min(clock_current),
+            nature::format_seconds_to_hour_min(clock_max),
+            GAME_NAME,
+            settings.version.as_str()
+        );
+    }
     if let Ok(mut text) = q_achievement_text.get_single_mut() {
         for i in 0..text.sections.len() - 1 {
             text.sections[i + 1].style.color = if bools[i] {

src/nature.rs

@@ -242,3 +242,26 @@ pub fn rotation_for_orbiting_body(orbit_distance: f64, mass: f64) -> f64 {
         0.0
     }
 }
+
+/// Assumes a circular 2D orbit in the invariable plane of the solar system
+/// Returns (seconds for a single orbit, current seconds of orbit)
+pub fn pos_to_orbit_time(pos: DVec3, orbited_pos: DVec3, orbited_mass: f64) -> (f64, f64) {
+    let rel_x = pos.x - orbited_pos.x;
+    let rel_z = pos.z - orbited_pos.z;
+    let orbit_distance = (rel_x * rel_x + rel_z * rel_z).sqrt();
+
+    // get total orbit seconds
+    let period = simple_orbital_period(orbited_mass, orbit_distance);
+
+    // get current orbital phase
+    let angle_radians = (rel_z).atan2(-rel_x);
+    let mut fraction = angle_radians / (PI * 2.0);
+    if fraction < 0.0 {
+        fraction += 1.0;
+    }
+    return (period, period * fraction);
+}
+
+pub fn format_seconds_to_hour_min(seconds: f64) -> String {
+    return format!("{:02.0}:{:02.0}", seconds / 3600.0, (seconds % 3600.0) / 60.0);
+}