trying to track the iss, wildly wrong

Cargo.lock

@@ -1871,7 +1871,9 @@ checksum = "c469d952047f47f91b68d1cba3f10d63c11d73e4636f24f08daf0278abf01c4d"
 dependencies = [
  "android-tzdata",
  "iana-time-zone",
+ "js-sys",
  "num-traits",
+ "wasm-bindgen",
  "windows-link",
 ]
 
@@ -5819,6 +5821,7 @@ version = "0.1.0"
 dependencies = [
  "anise",
  "bevy",
+ "chrono",
  "hifitime",
  "log",
  "nyx-space",

Cargo.toml

@@ -5,6 +5,7 @@ edition = "2024"
 
 [dependencies]
 anise = "0.5.4"
+chrono = "0.4.41"
 hifitime = "4.0.2"
 log = { version = "0.4.27", features = ["std"] }
 nyx-space = "2.1.0"

src/main.rs

@@ -1,48 +1,194 @@
+use std::{str::FromStr, sync::Arc, time::UNIX_EPOCH};
+
 use anise::{
     almanac::metaload::MetaFile,
     constants::{
         celestial_objects::{MOON, SUN},
         frames::{EARTH_J2000, IAU_EARTH_FRAME},
     },
+    frames::Frame,
+    prelude::Almanac,
 };
-use hifitime::{Epoch, Unit};
-use log::warn;
+use chrono::Utc;
+use hifitime::Epoch;
+
 use nyx_space::{
     cosmic::{Mass, MetaAlmanac, Orbit, SRPData},
     dynamics::{Harmonics, OrbitalDynamics, SolarPressure, SpacecraftDynamics},
-    io::{gravity::HarmonicsMem, ExportCfg},
+    io::gravity::HarmonicsMem,
     od::GroundStation,
     propagators::Propagator,
-    Spacecraft, State,
+    Spacecraft,
 };
 
-use bevy::{
-    color::palettes::css::BLUE,
-    pbr::wireframe::{WireframeColor, WireframeConfig, WireframePlugin},
-    platform::collections::HashSet,
-    prelude::*,
-};
+use bevy::{platform::collections::HashSet, prelude::*};
 
 fn main() {
     let mut app = App::new();
-    app.add_plugins((DefaultPlugins, WireframePlugin::default()))
+    app.add_plugins(DefaultPlugins)
         .insert_gizmo_config(DefaultGizmoConfigGroup, GizmoConfig::default())
         .insert_resource(DebugCamOffset::default())
-        .insert_resource(WireframeConfig {
-            global: false,
-            ..Default::default()
-        })
         .insert_resource(HomeCartesian::default())
+        .insert_resource(SpaceData::default())
+        .insert_resource(InterestPoint::default())
         .add_systems(Startup, (spawn_earth, spawn_camera))
         .add_systems(
             Update,
-            (close_on_esc, update_camera_offset, move_camera, draw_arrow),
+            (
+                close_on_esc,
+                update_camera_offset,
+                move_camera,
+                draw_arrow,
+                find_iss,
+            ),
         )
         .run();
 }
 
-// const RADIUS: f32 = 6378.0;
+fn find_iss(mut end: ResMut<InterestPoint>, mut data: ResMut<SpaceData>) {
+    let Ephemerides {
+        sma_km,
+        ecc,
+        inc_deg,
+        raan_deg,
+        aop_deg,
+        ma_deg,
+        epoch,
+    } = data.ephemerides.clone();
+
+    let now = std::time::SystemTime::now()
+        .duration_since(UNIX_EPOCH)
+        .unwrap()
+        .as_secs_f64();
+    let new_epoch = Epoch::from_unix_seconds(now);
+    let orbit = Orbit::try_keplerian_mean_anomaly(
+        sma_km, ecc, inc_deg, raan_deg, aop_deg, ma_deg, epoch, data.frame,
+    )
+    .unwrap();
+
+    let iss = Spacecraft::builder()
+        .orbit(orbit)
+        .mass(Mass::from_dry_mass(420_000.0))
+        .srp(SRPData {
+            area_m2: 2190.0,
+            coeff_reflectivity: 0.8,
+        })
+        .build();
+
+    let mut orbital_dyn = OrbitalDynamics::point_masses(vec![MOON, SUN]);
+    let harmonics = Harmonics::from_stor(
+        data.almanac.frame_from_uid(IAU_EARTH_FRAME).unwrap(),
+        HarmonicsMem::from_cof(&data.meta_file.uri, 21, 21, true).unwrap(),
+    );
+
+    orbital_dyn.accel_models.push(harmonics);
+    let srp = SolarPressure::default(EARTH_J2000, data.almanac.clone()).unwrap();
+    let dynamics = SpacecraftDynamics::from_model(orbital_dyn, srp);
+
+    let (iss, trajectory) = Propagator::default(dynamics)
+        .with(iss, data.almanac.clone())
+        .until_epoch_with_traj(new_epoch)
+        .unwrap();
+
+    data.ephemerides.sma_km = iss.orbit.sma_km().unwrap();
+    data.ephemerides.ecc = iss.orbit.ecc().unwrap();
+    data.ephemerides.inc_deg = iss.orbit.inc_deg().unwrap();
+    data.ephemerides.raan_deg = iss.orbit.raan_deg().unwrap();
+    data.ephemerides.aop_deg = iss.orbit.aop_deg().unwrap();
+    data.ephemerides.ma_deg = iss.orbit.ma_deg().unwrap();
+    data.ephemerides.epoch = new_epoch;
+
+    let aer = data
+        .almanac
+        .azimuth_elevation_range_sez(
+            iss.orbit,
+            data.home
+                .to_orbit(new_epoch, data.almanac.as_ref())
+                .unwrap(),
+            None,
+            None,
+        )
+        .unwrap();
+    let iss_loc = polar2cart(
+        aer.elevation_deg as f32,
+        aer.azimuth_deg as f32,
+        (aer.range_km / (R_FACTOR * 10.0)) as f32,
+    );
+    dbg!(aer);
+    end.0 = iss_loc;
+}
+
+#[derive(Debug, Resource, Clone)]
+pub struct Ephemerides {
+    pub sma_km: f64,
+    pub ecc: f64,
+    pub inc_deg: f64,
+    pub raan_deg: f64,
+    pub aop_deg: f64,
+    pub ma_deg: f64,
+    pub epoch: Epoch,
+}
+
+impl Default for Ephemerides {
+    fn default() -> Self {
+        Self {
+            sma_km: 419.0,
+            ecc: 0.0002408,
+            inc_deg: 51.6378,
+            raan_deg: 60.6053,
+            aop_deg: 142.7188,
+            ma_deg: 0.8794,
+            epoch: Epoch::from_gregorian_utc(2025, 5, 25, 6, 31, 36, 00),
+        }
+    }
+}
+
+#[derive(Resource)]
+pub struct SpaceData {
+    pub almanac: Arc<Almanac>,
+    pub meta_file: Arc<MetaFile>,
+    pub frame: Frame,
+    pub home: GroundStation,
+    pub radius: f64,
+    ephemerides: Ephemerides,
+}
+
+impl Default for SpaceData {
+    fn default() -> Self {
+        let almanac = Arc::new(MetaAlmanac::latest().map_err(Box::new).unwrap());
+        let frame = almanac.frame_from_uid(EARTH_J2000).unwrap();
+        let mut mf = MetaFile {
+            uri: "http://public-data.nyxspace.com/nyx/models/JGM3.cof.gz".to_string(),
+            crc32: Some(0xF446F027), // Specifying the CRC32 avoids redownloading it if it's cached.
+        };
+        mf.process(true).unwrap();
+
+        let home = GroundStation::from_point(
+            "Los Angeles".to_string(),
+            HOME_LAT as f64,
+            HOME_LONG as f64,
+            0.0,
+            frame,
+        );
+
+        let radius = frame.mean_equatorial_radius_km().unwrap();
+
+        Self {
+            almanac,
+            meta_file: Arc::new(mf),
+            frame,
+            home,
+            radius,
+            ephemerides: Ephemerides::default(),
+        }
+    }
+}
+
+#[derive(Debug, Default, Resource)]
+pub struct InterestPoint(pub Vec3);
+
 const RADIUS: f32 = 100.0;
+const R_FACTOR: f64 = 63.78;
 const HOME_LAT: f32 = 34.2;
 const HOME_LONG: f32 = -118.45;
 
@@ -184,8 +330,8 @@ fn update_camera_offset(
     }
 }
 
-fn draw_arrow(home: Res<HomeCartesian>, mut gizmos: Gizmos) {
+fn draw_arrow(home: Res<HomeCartesian>, end: Res<InterestPoint>, mut gizmos: Gizmos) {
     let start = home.pos;
-    let end = home.pos * 2.0;
+    let end = end.0;
     gizmos.arrow(start, end, Color::linear_rgb(1.0, 1.0, 0.0));
 }