From dd4f8fb20265c317833b36e1b5e19d93833daeda Mon Sep 17 00:00:00 2001
From: xfy <i@rua.plus>
Date: Thu, 16 Jul 2026 18:27:09 +0800
Subject: [PATCH] feat(ui): Planets control panel + dirty-flag respawn on
 seed/count/k

---
 src/ui.rs | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/src/ui.rs b/src/ui.rs
index 542b3a1..d5ea050 100644
--- a/src/ui.rs
+++ b/src/ui.rs
@@ -6,6 +6,7 @@ pub fn ui_system(
     mut params: ResMut<crate::params::BlackHoleParams>,
     mut camera: ResMut<crate::camera::OrbitCamera>,
     mut wants: ResMut<crate::camera::WantsPointer>,
+    mut planet_dirty: ResMut<crate::scene::planets::PlanetSystemDirty>,
 ) {
     if let Ok(ctx) = contexts.ctx_mut() {
         egui::Window::new("Controls")
@@ -53,6 +54,36 @@ pub fn ui_system(
                             egui::Slider::new(&mut params.disk_temp, 1000.0..=50000.0).text("Temperature (K)"),
                         );
                     });
+                egui::CollapsingHeader::new("Planets")
+                    .default_open(false)
+                    .show(ui, |ui| {
+                        // Record state before edits; if seed/count/k/enabled change,
+                        // flag dirty so spawn_planet_system regenerates next frame.
+                        // (time_scale excluded: it only scales orbit_system's time,
+                        //  no respawn needed.)
+                        let prev = (
+                            params.planets_enabled,
+                            params.planet_count_target,
+                            params.planet_radius_factor,
+                            params.planet_seed,
+                        );
+                        ui.checkbox(&mut params.planets_enabled, "Enable");
+                        ui.add(egui::Slider::new(&mut params.planet_count_target, 0..=8).text("Count"));
+                        ui.add(egui::Slider::new(&mut params.planet_radius_factor, 1.5..=5.0).text("Radius factor k"));
+                        let isco = crate::physics::kerr_isco(params.spin);
+                        ui.label(format!("ISCO: {:.3} → r = {:.3}", isco, params.planet_radius_factor * isco));
+                        ui.add(egui::Slider::new(&mut params.planet_seed, 0..=1000).text("Seed"));
+                        ui.add(egui::Slider::new(&mut params.planet_time_scale, 1.0..=200.0).text("Time scale"));
+                        let curr = (
+                            params.planets_enabled,
+                            params.planet_count_target,
+                            params.planet_radius_factor,
+                            params.planet_seed,
+                        );
+                        if curr != prev {
+                            planet_dirty.0 = true;
+                        }
+                    });
                 egui::CollapsingHeader::new("Disk Turbulence")
                     .default_open(true)
                     .show(ui, |ui| {