P2/P3 issues: network-fed launchers priced into smart routes (#4), stable blast light ids (#15), retargeted smart drones replanned round the defences (#21), sim tick without per-unit clones and linear scans (#26), ground cache swept rarely (#31), Oreshnik pieces keep their sector (#32), drives with acceleration and fire only once aimed (#33), radar monitor range (#19), delayed sound volume (#22), world change clears transient state (#23), score line always shown (#24), replay map without full paths (#25), text fit by bisection (#27), docs (#29), glow occlusion by ray distance (#14), blasts composited nearest first (#16)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

README.md

@@ -23,9 +23,10 @@ python3 tools/airdef.py play    # запустить (аргументы игр
 (`tools/gen_sounds.py`, нужны numpy и ffmpeg), собирает и ставит мод. Сгенерированные файлы лежат в репозитории,
 так что для обычной сборки нужен только Rust.
 
-CI: `.gitea/workflows/build.yml` на каждый пуш собирает мод и игру для Linux, а пуш в `main` публикует релиз
-`build-N`; `.gitea/workflows/desktop.yml` (запуск вручную с тегом релиза) собирает игру для macOS и Windows на
-раннерах с метками `macos-latest` / `windows-latest` и дописывает архивы в релиз.
+CI: `.gitea/workflows/build.yml` на каждый пуш собирает только мод (`airdef.hmod`), а пуш в `main` публикует его
+релизом `build-N`. Игру-форк собирают вручную: `.gitea/workflows/game.yml` (Linux) и `.gitea/workflows/desktop.yml`
+(macOS и Windows, на раннерах с метками `macos-latest` / `windows-latest`); оба запускаются из Actions с тегом
+готового релиза и дописывают свои архивы в него.
 
 ## Как играть
 
@@ -130,7 +131,7 @@ API мода `render.set-lights` (до 512, плавно интерполиру
   перехватчиков (жёлтые), сбития (x), прилёты, шкала времени с событиями; время идёт само, колесо мыши перематывает;
 - **повтор момента** — клик по событию в списке: «призраки» дронов и ракет снова летят в мире, камера идёт за
   целью, потом за перехватчиком (или смотрит из пушки, со стороны на прилёт), в момент сбития время замедляется;
-- **полный повтор** — весь налёт, камера-режиссёр сама выбирает, за чем следить; колесо — скорость (×0.5–×16);
+- **полный повтор** — весь налёт, камера-режиссёр сама выбирает, за чем следить; колесо — перемотка, стрелки — скорость;
 - **лучшие моменты** — нарезка до 8 самых интересных событий (перехват баллистики и гиперзвука, поражения
   объектов, потерянные комплексы, разделение «Орешника») с титрами и замедлением; колесо листает моменты.
 

airdef-mod/shaders/effects.wgsl

@@ -197,7 +197,10 @@ fn post(uv: vec2<f32>, pixel: vec2<f32>) -> vec4<f32> {
         if age < 0.0 || age > 10.0 { continue; }
         let p = project(a.xyz);
         if p.z <= 0.5 { continue; }
-        let visible = select(0.25, 1.0, scene_distance(p.xy) > p.z - a.w);
+        // Ray distance on both sides: `p.z` is the depth along the view axis, which is shorter
+        // than the distance along the ray towards the screen edge.
+        let dist = length(a.xyz - frame.camera.xyz);
+        let visible = select(0.25, 1.0, scene_distance(p.xy) > dist - a.w);
         let f = exp(-age * 0.7) * min(a.w / 4.0, 2.5) * visible;
         let r = screen_radius(a.xyz, a.w * 2.5) + 20.0;
         let dd = length(px - p.xy * frame.resolution.xy) / r;
@@ -211,7 +214,7 @@ fn post(uv: vec2<f32>, pixel: vec2<f32>) -> vec4<f32> {
         let b = frame.params[LIGHT_BASE + 2 * j + 1];
         let p = project(a.xyz);
         if p.z <= 0.3 { continue; }
-        if scene_distance(p.xy) < p.z - a.w * 1.5 { continue; }
+        if scene_distance(p.xy) < length(a.xyz - frame.camera.xyz) - a.w * 1.5 { continue; }
         let r = screen_radius(a.xyz, a.w) + 3.0;
         let dd = length(px - p.xy * frame.resolution.xy) / r;
         let flicker = 0.85 + 0.15 * noise3(vec3<f32>(a.xyz * 0.7 + vec3<f32>(t_now * 1.3)));

airdef-mod/src/lib.rs

@@ -56,6 +56,9 @@ struct AirDef {
     sim: Sim,
     ground: Ground,
     dirty: bool,
+    /// Wall-clock-free pacing of autosaves: the tick before which none is written (at most one a
+    /// second while guns fire, and a pause after a failed write).
+    next_save: u64,
     hud_shown: bool,
     /// The system the monitor shows (K cycles), none: hidden.
     monitor: Option<usize>,
@@ -82,8 +85,17 @@ struct AirDef {
     menu: Option<Page>,
     /// Where the player is, for the sounds' delay and far variants.
     listener: DVec3,
-    /// Sounds on their way to the player at the speed of sound: (tick, event, at, pitch).
-    pending: Vec<(u64, String, DVec3, f32)>,
+    /// Sounds on their way to the player at the speed of sound.
+    pending: Vec<PendingSound>,
+}
+
+/// A sound heard later: when, what, where, and how loud and high it was.
+struct PendingSound {
+    due: u64,
+    name: String,
+    at: DVec3,
+    volume: f32,
+    pitch: f32,
 }
 
 /// Blocks a tick the sound travels (343 m/s).
@@ -307,7 +319,8 @@ impl AirDef {
             let size = b.size;
             let glow = (-age / (b.life as f32 * 0.15).max(1.0)).exp();
             let flash = (-age * 0.35).exp() * 4.0;
-            let id = 0x6100_0000 ^ (b.start as u32).wrapping_mul(31) ^ (b.at.x as i32 as u32).wrapping_mul(7);
+            // Its own id range: the models' and the systems' ids are small numbers.
+            let id = 0x6100_0000 | (b.id & 0x00ff_ffff);
             add(id, b.at + DVec3::Y * size as f64 * 0.5, (1.0, 0.58, 0.25), size * size * 18.0 * (glow + flash), size * 14.0);
         }
         for s in &self.sim.sams {
@@ -352,7 +365,14 @@ impl AirDef {
         let mut p = vec![0.0f32; 4];
         p[0] = self.sim.tick as f32;
         p[3] = if self.hd { 1.0 } else { 0.0 };
-        let blasts: Vec<&sim::Blast> = self.sim.blasts.iter().rev().take(48).collect();
+        let mut blasts: Vec<&sim::Blast> = self.sim.blasts.iter().rev().take(48).collect();
+        // The shader composites the volumes front to back with one shared transmittance, so
+        // the nearest to the player goes first. This is exact for volumes that do not
+        // overlap; where two intersect, no order by centre is right along every ray.
+        if let Some(pl) = player() {
+            let e = eye(&pl);
+            blasts.sort_by(|a, b| a.at.distance_squared(e).total_cmp(&b.at.distance_squared(e)));
+        }
         p[1] = blasts.len() as f32;
         for b in &blasts {
             p.extend([b.at.x as f32, b.at.y as f32, b.at.z as f32, b.size]);
@@ -441,7 +461,7 @@ impl AirDef {
                 if delay == 0 {
                     render::play_sound(&name, at.x, at.y, at.z, volume, pitch);
                 } else if self.pending.len() < 256 {
-                    self.pending.push((now + delay, name, at, pitch));
+                    self.pending.push(PendingSound { due: now + delay, name, at, volume, pitch });
                 }
             } else {
                 render::play_sound(event, at.x, at.y, at.z, volume, pitch);
@@ -449,9 +469,9 @@ impl AirDef {
         }
         let mut i = 0;
         while i < self.pending.len() {
-            if self.pending[i].0 <= now {
-                let (_, name, at, pitch) = self.pending.swap_remove(i);
-                render::play_sound(&name, at.x, at.y, at.z, 1.0, pitch);
+            if self.pending[i].due <= now {
+                let s = self.pending.swap_remove(i);
+                render::play_sound(&s.name, s.at.x, s.at.y, s.at.z, s.volume, s.pitch);
             } else {
                 i += 1;
             }
@@ -517,10 +537,17 @@ impl AirDef {
         for (kind, roles) in &self.sim.roles {
             text += &format!("roles {} {}\n", kind.key(), roles);
         }
-        if let Err(e) = storage::set(&self.state_key(), text.as_bytes()) {
-            horizon_mod_sdk::warn(&format!("could not save: {e}"));
+        // Clean only once written: a failed write is tried again after a pause.
+        match storage::set(&self.state_key(), text.as_bytes()) {
+            Ok(()) => {
+                self.dirty = false;
+                self.next_save = self.sim.tick + 20;
+            }
+            Err(e) => {
+                horizon_mod_sdk::warn(&format!("could not save: {e}"));
+                self.next_save = self.sim.tick + 200;
+            }
         }
-        self.dirty = false;
     }
 
     fn load(&mut self) {
@@ -635,11 +662,18 @@ impl AirDef {
         let shader = self.sim.shader;
         let seed = game::get_clock().map_or(0x5eed, |c| c.game_time.wrapping_mul(2654435761) ^ 0x9e37);
         self.sim = Sim::new(seed);
+        self.next_save = 0;
         self.sim.shader = shader;
         self.ground = Ground::default();
         self.monitor = None;
         self.grid = false;
         self.grid_ids.clear();
+        // The last world's transient state: its sounds were due on its own
+        // clock, its picked unit may have another meaning in this one, and
+        // its models would stay until the next full model list.
+        self.pending.clear();
+        self.moving = None;
+        render::set_models(&[]);
         self.far = true;
         self.world = Some(world);
         self.load();
@@ -885,6 +919,7 @@ impl Mod for AirDef {
             sim: Sim::new(seed),
             ground: Ground::default(),
             dirty: false,
+            next_save: 0,
             hud_shown: false,
             monitor: None,
             monitor_shown: false,
@@ -1044,7 +1079,7 @@ impl Mod for AirDef {
             self.health_mark = mark;
             self.dirty = true;
         }
-        if self.dirty {
+        if self.dirty && self.sim.tick >= self.next_save {
             self.save();
         }
     }

airdef-mod/src/monitor.rs

@@ -25,11 +25,22 @@ fn fit(t: String, w: f32) -> String {
     if render::text_width(&t) <= w {
         return t;
     }
-    let mut cut: String = t;
-    while !cut.is_empty() && render::text_width(&format!("{cut}…")) > w {
-        cut.pop();
+    // The width grows with the prefix: bisect over its char starts, so a long
+    // label costs a few host calls rather than one per dropped char.
+    let starts: Vec<usize> = t.char_indices().map(|(i, _)| i).collect();
+    let (mut lo, mut hi) = (0, starts.len());
+    while lo < hi {
+        let mid = (lo + hi) / 2;
+        if render::text_width(&format!("{}…", &t[..starts[mid]])) <= w {
+            lo = mid + 1;
+        } else {
+            hi = mid;
+        }
     }
-    format!("{cut}…")
+    if lo == 0 {
+        return "…".into();
+    }
+    format!("{}…", &t[..starts[lo - 1]])
 }
 
 fn argb(rgb: u32, a: u32) -> u32 {
@@ -101,7 +112,13 @@ fn cell(sim: &Sim, index: usize, x: f32, y: f32, w: f32, h: f32, s: &mut Vec<Sha
             s.push(quad(p(a0, r - 0.4), p(a0, r + 0.4), p(a1, r + 0.4), p(a1, r - 0.4), 0x9040FF60));
         }
     }
-    let reach = sam.kind.range();
+    // A system that only fires (no radar) has no reach: a radar's sensor
+    // range stands in, and nothing is divided by zero.
+    let reach = match sam.kind.range() {
+        r if r > 0.0 => r,
+        _ => spec.sensor,
+    };
+    let scale = if reach > 0.0 { rr as f64 / (reach * 1.25) } else { 0.0 };
     let sweep = (tick as f32 * 0.12 + index as f32) % std::f32::consts::TAU;
     for k in 0..6 {
         let a1 = sweep - k as f32 * 0.09;
@@ -115,11 +132,11 @@ fn cell(sim: &Sim, index: usize, x: f32, y: f32, w: f32, h: f32, s: &mut Vec<Sha
     for d in sim.drones.iter().filter(|d| d.alive() && sam.seen.contains(&d.id)) {
         let rel = d.pos - sam.pos;
         let flat = (rel.x * rel.x + rel.z * rel.z).sqrt();
-        if flat > reach * 1.25 {
+        if reach <= 0.0 || flat > reach * 1.25 {
             continue;
         }
         seen += 1;
-        let k = (rr as f64 / (reach * 1.25)) as f32;
+        let k = scale as f32;
         let (bx, by) = (rx + rel.x as f32 * k, ry + rel.z as f32 * k);
         let allowed = sam.roles & d.kind.spec().class.bit() != 0;
         let color = if Some(d.id) == target.map(|t| t.id) {

airdef-mod/src/panel.rs

@@ -10,6 +10,8 @@ const CYAN: u32 = 0x9FE0FF;
 const GREY: u32 = 0xB0B0B0;
 const YELLOW: u32 = 0xFFE070;
 const GREEN: u32 = 0x80FF90;
+/// The most lines the summary holds (the HUD's room).
+const MAX_LINES: usize = 16;
 
 /// Metres (a block is a metre) as a short distance.
 pub fn distance(m: f64) -> String {
@@ -77,7 +79,15 @@ pub fn summary(sim: &Sim, air: &[&Drone], player: DVec3) -> Vec<Line> {
     if !sim.missiles.is_empty() {
         lines.push(line(format!("Перехватчиков в полёте: {}", sim.missiles.len()), YELLOW));
     }
-    for sam in sim.sams.iter().take(8) {
+    // The score is the last line and always shown: the unit list gets what
+    // room is left, and cuts its own tail.
+    let room = (MAX_LINES - 1).saturating_sub(lines.len());
+    let total = sim.sams.len();
+    let mut shown = total.min(8);
+    if shown + usize::from(total > 8) > room {
+        shown = room.saturating_sub(1);
+    }
+    for sam in sim.sams.iter().take(shown) {
         let mut text = if sam.kind.armed() {
             format!("{} [{}]", sam.status(), crate::sim::roles_text(sam.roles))
         } else {
@@ -91,15 +101,16 @@ pub fn summary(sim: &Sim, air: &[&Drone], player: DVec3) -> Vec<Line> {
         }
         lines.push(line(text, CYAN));
     }
-    if sim.sams.len() > 8 {
-        lines.push(line(format!("…и ещё {} комплексов", sim.sams.len() - 8), CYAN));
+    if total > shown && room > 0 {
+        lines.push(line(format!("…и ещё {} комплексов", total - shown), CYAN));
     }
+    // Room for the score whatever came before.
+    lines.truncate(MAX_LINES - 1);
     let real = sim.launched.saturating_sub(0);
     let rate = if real > 0 { sim.kills as f64 * 100.0 / real as f64 } else { 0.0 };
     lines.push(line(
         format!("Сбито {} из {} ({rate:.0}%) · прорвалось {}", sim.kills, sim.launched, sim.hits),
         GREY,
     ));
-    lines.truncate(16);
     lines
 }

airdef-mod/src/replay.rs

@@ -5,7 +5,8 @@
 //! behind the drone, then behind the interceptor or from the side — slowing
 //! time round the moment itself.
 use crate::panel::distance;
-use crate::sim::record::{EventKind, Recording, What};
+use crate::sim::record::{EventKind, Recording, STEP, What};
+use std::cell::Cell;
 use crate::sim::{Class, DroneKind, Out, Sim};
 use glam::DVec3;
 use horizon_mod_sdk::render::{CameraView, FillShape, Point, QuadShape, Rect, Shape, TextShape, ViewShape};
@@ -55,6 +56,8 @@ pub struct Player {
     /// Ticks the controls stay on screen.
     help: u32,
     pub done: bool,
+    /// The map's area, worked out on the first map frame.
+    area: Cell<Option<[f64; 4]>>,
 }
 
 /// What the replay's keys do.
@@ -201,6 +204,7 @@ impl Player {
         };
         let _ = sim;
         Player {
+            area: Cell::new(None),
             rec,
             mode,
             t: start,
@@ -581,34 +585,16 @@ impl Player {
     fn map(&self, rec: &Recording, gw: f32, gh: f32) -> Vec<Shape> {
         let mut s = vec![fill(0.0, 0.0, gw, gh, 0xF0060A08)];
         let o = rec.origin;
-        // The area: everything that flew, but not far beyond the systems.
-        let mut lo = (f64::MAX, f64::MAX);
-        let mut hi = (f64::MIN, f64::MIN);
-        let mut grow = |p: DVec3| {
-            lo = (lo.0.min(p.x), lo.1.min(p.z));
-            hi = (hi.0.max(p.x), hi.1.max(p.z));
+        // The area is the same every tick: worked out once for the recording.
+        let [l0, l1, h0, h1] = match self.area.get() {
+            Some(a) => a,
+            None => {
+                let a = area(rec, o);
+                self.area.set(Some(a));
+                a
+            }
         };
-        for tr in &rec.tracks {
-            if let What::Drone(k) = tr.what
-                && k.spec().ballistic.is_some()
-            {
-                continue;
-            }
-            for p in tr.path(o, 20, rec.len as f64) {
-                grow(p);
-            }
-        }
-        for sam in &rec.sams {
-            grow(sam.2 - DVec3::splat(60.0));
-            grow(sam.2 + DVec3::splat(60.0));
-        }
-        for p in &rec.objects {
-            grow(*p);
-        }
-        if lo.0 > hi.0 {
-            lo = (o.x - 200.0, o.z - 200.0);
-            hi = (o.x + 200.0, o.z + 200.0);
-        }
+        let (lo, hi) = ((l0, l1), (h0, h1));
         let (top, bottom) = (20.0f32, 34.0f32);
         let (aw, ah) = (gw - 16.0, gh - top - bottom);
         let k = (aw as f64 / (hi.0 - lo.0).max(1.0)).min(ah as f64 / (hi.1 - lo.1).max(1.0));
@@ -638,7 +624,9 @@ impl Player {
             let (x, y) = at(*p);
             s.push(fill(x - 3.0, y - 3.0, 6.0, 6.0, 0xFFFFFFFF));
         }
-        // Tracks up to now: a budget of segments shared out.
+        // Tracks up to now: a budget of segments shared out. The stride is
+        // worked out from the points there are, so only the segments drawn
+        // are ever copied.
         let n = rec.tracks.len().max(1);
         let per = (640 / n).clamp(2, 14);
         for tr in &rec.tracks {
@@ -647,16 +635,21 @@ impl Player {
                 What::Drone(_) => (0x90FF4040, 0xFFFF6060),
                 What::Missile(..) => (0x90FFD040, 0xFFFFE070),
             };
-            let pts = tr.path(o, 1, self.t);
+            let upto = ((self.t - tr.first as f64) / STEP as f64).floor();
+            if upto < 0.0 {
+                continue;
+            }
+            let last = ((tr.last() - tr.first) / STEP) as f64;
+            let count = upto.min(last) as usize + 1;
+            if count < 2 {
+                continue;
+            }
+            let pts = tr.path(o, count.div_ceil(per).max(1), self.t);
             if pts.len() < 2 {
                 continue;
             }
-            let every = pts.len().div_ceil(per).max(1);
             let mut prev = at(pts[0]);
-            for (i, p) in pts.iter().enumerate().skip(1) {
-                if i % every != 0 && i != pts.len() - 1 {
-                    continue;
-                }
+            for p in pts.iter().skip(1) {
                 let q = at(*p);
                 if inside(prev) && inside(q) {
                     s.push(line(prev, q, 1.0, color));
@@ -718,6 +711,41 @@ impl Player {
     }
 }
 
+/// The ground the map shows, as [lo x, lo z, hi x, hi z]: everything that
+/// flew (not the ballistic falls), with the systems and objects, or round the
+/// origin when nothing did.
+fn area(rec: &Recording, o: DVec3) -> [f64; 4] {
+    let mut lo = (f64::MAX, f64::MAX);
+    let mut hi = (f64::MIN, f64::MIN);
+    let mut grow = |p: DVec3| {
+        lo = (lo.0.min(p.x), lo.1.min(p.z));
+        hi = (hi.0.max(p.x), hi.1.max(p.z));
+    };
+    for tr in &rec.tracks {
+        if let What::Drone(k) = tr.what
+            && k.spec().ballistic.is_some()
+        {
+            continue;
+        }
+        for p in tr.path(o, 20, rec.len as f64) {
+            grow(p);
+        }
+    }
+    // The systems, with some room round them.
+    for sam in &rec.sams {
+        grow(sam.2 - DVec3::splat(60.0));
+        grow(sam.2 + DVec3::splat(60.0));
+    }
+    for p in &rec.objects {
+        grow(*p);
+    }
+    if lo.0 > hi.0 {
+        lo = (o.x - 200.0, o.z - 200.0);
+        hi = (o.x + 200.0, o.z + 200.0);
+    }
+    [lo.0, lo.1, hi.0, hi.1]
+}
+
 impl Player {
     pub fn event_clip(rec: &Recording, i: usize) -> Mode {
         Mode::Clips { list: vec![clip(rec, i)], at: 0, reel: false }

airdef-mod/src/sim/damage.rs

@@ -189,6 +189,8 @@ impl Sim {
         for h in &mut self.target_health {
             *h = 100.0;
         }
+        // The wrecks' ammunition still to cook off goes with them.
+        self.later.clear();
         n
     }
 

airdef-mod/src/sim/ew.rs

@@ -159,8 +159,10 @@ impl Sim {
             return;
         }
         let pick = |i: usize, list: &[(u32, DVec3)]| list[i % list.len()].1;
+        // The drones sent at a new target: (waiting in the queue, index), to get a new route.
+        let mut retargeted: Vec<(bool, usize)> = Vec::new();
         let mut n = 0usize;
-        for (_, d) in self.queue.iter_mut().filter(|(_, d)| d.smart) {
+        for (qi, (_, d)) in self.queue.iter_mut().enumerate().filter(|(_, (_, d))| d.smart) {
             let hunter = matches!(d.kind, DroneKind::Lancet | DroneKind::Kh22 | DroneKind::Zircon);
             if !hunter && !(d.kind == DroneKind::Shahed && n % 4 == 0) {
                 n += 1;
@@ -173,18 +175,80 @@ impl Sim {
             let to = if !ew.is_empty() { pick(n, &ew) } else { pick(n, &known) };
             d.target = to;
             d.route.clear();
+            retargeted.push((true, qi));
             n += 1;
         }
         // In flight: a target system destroyed — the next known one, or keep going.
-        for d in self.drones.iter_mut().filter(|d| d.alive() && d.smart) {
+        for (di, d) in self.drones.iter_mut().enumerate().filter(|(_, d)| d.alive() && d.smart) {
             let aimed_at_wreck = self.sams.iter().any(|s| !s.alive() && s.pos.distance(d.target) < 6.0);
             if aimed_at_wreck {
                 let next = known.iter().min_by(|a, b| a.1.distance(d.pos).total_cmp(&b.1.distance(d.pos)));
                 if let Some((_, at)) = next {
                     d.target = *at;
                     d.route.clear();
+                    retargeted.push((false, di));
                 }
             }
         }
+        self.replan_routes(&retargeted);
+    }
+
+    /// Routes round the known defences for drones that were just sent at a new target, from where they are
+    /// (or wait). One grid and one set of prices cover them all, and the work is the planner's share for a
+    /// tick: those left over fly straight, as they did before there was a replan. A Lancet's strike on a
+    /// unit and the ballistic missiles go straight on purpose, as in the raid's own plan.
+    fn replan_routes(&mut self, jobs: &[(bool, usize)]) {
+        let drone = |s: &Sim, (queued, i): (bool, usize)| if queued { s.queue[i].1.clone() } else { s.drones[i].clone() };
+        let jobs: Vec<(bool, usize)> = jobs
+            .iter()
+            .copied()
+            .filter(|&j| {
+                let d = drone(self, j);
+                let spec = d.kind.spec();
+                d.smart && spec.ballistic.is_none() && !spec.decoy && d.kind != DroneKind::Lancet
+            })
+            .collect();
+        if jobs.is_empty() {
+            return;
+        }
+        // One grid over all their starts and goals, with room round them to go by.
+        let (mut lo, mut hi) = (DVec3::splat(f64::INFINITY), DVec3::splat(f64::NEG_INFINITY));
+        for &j in &jobs {
+            let d = drone(self, j);
+            for p in [d.pos, d.target] {
+                lo = lo.min(p);
+                hi = hi.max(p);
+            }
+        }
+        let span = (hi.x - lo.x).max(hi.z - lo.z) / 2.0 + 450.0;
+        let cell = raid::CELL.max(2.0 * span / raid::CELLS as f64);
+        let centre = (lo + hi) / 2.0;
+        let grid = raid::Grid { min: centre - DVec3::new(span, 0.0, span), cell, size: (2.0 * span / cell) as i32 + 1 };
+        let mut prices: HashMap<DroneKind, Vec<f32>> = HashMap::new();
+        let mut routes: HashMap<(DroneKind, (i32, i32), (i32, i32)), Vec<DVec3>> = HashMap::new();
+        let mut work = 0usize;
+        for j in jobs {
+            let d = drone(self, j);
+            if work >= raid::WORK_PER_TICK {
+                break;
+            }
+            let key = (d.kind, grid.index(d.pos), grid.index(d.target));
+            let route = match routes.get(&key) {
+                Some(r) => r.clone(),
+                None => {
+                    if !prices.contains_key(&d.kind) {
+                        let (p, cost) = self.price_grid(&grid, d.kind);
+                        work += cost;
+                        prices.insert(d.kind, p);
+                    }
+                    let (r, cost) = raid::plan_route(&grid, &prices[&d.kind], d.pos, d.target);
+                    work += cost;
+                    routes.insert(key, r.clone());
+                    r
+                }
+            };
+            let d = if j.0 { &mut self.queue[j.1].1 } else { &mut self.drones[j.1] };
+            d.route = route;
+        }
     }
 }

airdef-mod/src/sim/logistics.rs

@@ -43,6 +43,10 @@ impl Sim {
                 self.reload_now(i, out);
             }
         }
+        // A destroyed truck drops its job, for another to take.
+        for s in self.sams.iter_mut().filter(|s| s.kind == SamKind::Tzm && !s.alive()) {
+            s.job = None;
+        }
         // The trucks: a job each, when idle.
         for t in 0..self.sams.len() {
             let truck = &self.sams[t];
@@ -66,13 +70,17 @@ impl Sim {
                     }
                     self.sams[t].job = None;
                 } else if self.sams[j].alive() && (self.sams[j].empty || self.sams[j].kind == SamKind::Depot) {
-                    continue; // still on its way (a new order follows when it arrives)
+                    // Stopped short of it (it drove off meanwhile): on to where it stands now.
+                    let to = self.sams[j].pos;
+                    let side = horizontal(at - to).normalize_or(DVec3::X) * (HANDOVER * 0.6);
+                    self.order_move(t, to + side);
+                    continue;
                 } else {
                     self.sams[t].job = None;
                 }
             }
             // A new job: the nearest waiting system no other truck is driving to, or a depot to load at.
-            let taken: Vec<u32> = self.sams.iter().filter(|s| s.kind == SamKind::Tzm).filter_map(|s| s.job).collect();
+            let taken: Vec<u32> = self.sams.iter().filter(|s| s.kind == SamKind::Tzm && s.alive()).filter_map(|s| s.job).collect();
             let next = if self.sams[t].cargo > 0 {
                 self.sams
                     .iter()

airdef-mod/src/sim/mod.rs

@@ -18,6 +18,8 @@ mod lights;
 mod logistics;
 mod orders;
 mod units;
+#[cfg(test)]
+mod regress;
 pub use ew::EW_RADIUS;
 pub use units::{Family, SamKind};
 use units::Muzzle;
@@ -52,6 +54,8 @@ pub struct Particle {
 /// A blast the post-processing shader draws as a fireball, flash and shock.
 #[derive(Clone, Copy)]
 pub struct Blast {
+    /// Never reused while the simulation lives: the HD light keeps its identity through the blast's life.
+    pub id: u32,
     pub at: DVec3,
     /// Fireball radius in blocks.
     pub size: f32,
@@ -161,6 +165,33 @@ fn slew(from: f64, to: f64, rate: f64) -> f64 {
     from + angle_diff(from, to).clamp(-rate, rate)
 }
 
+/// One axis of a drive: speeds up towards `err` (the angle still to turn), brakes in time to stop on it,
+/// and returns the turn this tick. Arriving takes the last bit at once, so there is no overshoot or jitter.
+fn drive(vel: &mut f64, err: f64, speed: f64, accel: f64) -> f64 {
+    // The fastest it may go and still stop within what is left.
+    let fastest = (2.0 * accel * err.abs()).sqrt().min(speed);
+    let want = fastest.copysign(err);
+    *vel = (*vel + (want - *vel).clamp(-accel, accel)).clamp(-speed, speed);
+    if vel.abs() >= err.abs() && vel.signum() == err.signum() {
+        *vel = 0.0;
+        return err;
+    }
+    *vel
+}
+
+/// Moves one system's claim from the drone it had to the one it has, in a count of claims per drone.
+fn retarget(counts: &mut HashMap<u32, u32>, from: Option<u32>, to: Option<u32>) {
+    if from == to {
+        return;
+    }
+    if let Some(n) = from.and_then(|id| counts.get_mut(&id)) {
+        *n = n.saturating_sub(1);
+    }
+    if let Some(id) = to {
+        *counts.entry(id).or_insert(0) += 1;
+    }
+}
+
 fn angle_diff(from: f64, to: f64) -> f64 {
     (to - from + std::f64::consts::PI).rem_euclid(TAU) - std::f64::consts::PI
 }
@@ -173,8 +204,13 @@ pub struct Ground {
     known: HashMap<(i32, i32), (i32, u64)>,
     wanted: Vec<(i32, i32)>,
     asked: std::collections::HashSet<(i32, i32)>,
+    /// The tick of the last full clean-up (a big cache would otherwise be scanned on every answer).
+    swept: u64,
 }
 
+/// Ticks between full clean-ups of a big ground cache.
+const SWEEP_EVERY: u64 = 200;
+
 impl Ground {
     /// One above the highest solid block, if known; the column is asked for
     /// when it isn't (or is old).
@@ -182,7 +218,9 @@ impl Ground {
         let key = (p.x.floor() as i32, p.z.floor() as i32);
         match self.known.get(&key) {
             Some(&(y, when)) => {
-                if now.saturating_sub(when) > 200 && self.wanted.len() < 256 && self.asked.insert(key) {
+                // Refreshes of known columns take at most a quarter of the questions: the rest
+                // stay free for columns never seen, or those would starve.
+                if now.saturating_sub(when) > 200 && self.wanted.len() < 64 && self.asked.insert(key) {
                     self.wanted.push(key);
                 }
                 (y > -64).then_some(f64::from(y))
@@ -199,8 +237,9 @@ impl Ground {
         for (x, z, y) in answers {
             self.known.insert((x, z), (y, now));
         }
-        if self.known.len() > 300_000 {
-            self.known.retain(|_, (_, when)| now - *when < 2000);
+        if self.known.len() > 300_000 && now.saturating_sub(self.swept) >= SWEEP_EVERY {
+            self.swept = now;
+            self.known.retain(|_, (_, when)| now.saturating_sub(*when) < 2000);
         }
     }
     pub fn take_wanted(&mut self) -> Vec<(i32, i32)> {
@@ -932,6 +971,9 @@ pub struct Sam {
     pub heading: f64,
     yaw: f64,
     pitch: f64,
+    /// How fast the mount turns now (radians a tick); not saved, a loaded system starts at rest.
+    yaw_vel: f64,
+    pitch_vel: f64,
     pub missiles: u32,
     pub bursts: u32,
     cooldown: u32,
@@ -985,6 +1027,8 @@ impl Sam {
             heading,
             yaw: heading,
             pitch: spec.rest_pitch,
+            yaw_vel: 0.0,
+            pitch_vel: 0.0,
             missiles: spec.missile.as_ref().map_or(0, |m| m.magazine),
             bursts: spec.gun.as_ref().map_or(0, |g| g.bursts),
             cooldown: 40,
@@ -1024,6 +1068,21 @@ impl Sam {
         self.health > 0.0
     }
     /// How well it still works: turning, aiming, its radar's reach.
+    /// Turns the mount towards `yaw` (and `pitch`, if it elevates) under its drive's limits; a damaged
+    /// system has the less of both speed and acceleration.
+    fn aim_towards(&mut self, yaw: f64, pitch: Option<f64>) {
+        let d = self.kind.spec().drive();
+        let fit = self.fitness();
+        self.yaw += drive(&mut self.yaw_vel, angle_diff(self.yaw, yaw), d.yaw.0 * fit, d.yaw.1 * fit);
+        if let Some(pitch) = pitch {
+            self.pitch += drive(&mut self.pitch_vel, pitch - self.pitch, d.pitch.0 * fit, d.pitch.1 * fit);
+        }
+    }
+    /// The mount stops where it is (a march, a deployment: the vehicle drives it directly).
+    pub(super) fn halt_mount(&mut self) {
+        self.yaw_vel = 0.0;
+        self.pitch_vel = 0.0;
+    }
     fn fitness(&self) -> f64 {
         0.45 + 0.55 * self.health.clamp(0.0, 1.0)
     }
@@ -1090,6 +1149,8 @@ pub struct Sim {
     fx: Vec<(u32, Fx)>,
     /// Blasts for the post-processing shader.
     pub blasts: Vec<Blast>,
+    /// The next blast's id (separate from `next`, so the other units' ids stay as they were).
+    blast_seq: u32,
     next: u32,
     pub rng: Rng,
     pub tick: u64,
@@ -1140,6 +1201,7 @@ impl Sim {
             targets: Vec::new(),
             fx: Vec::new(),
             blasts: Vec::new(),
+            blast_seq: 0,
             next: 1,
             rng: Rng::new(seed),
             tick: 0,
@@ -1308,8 +1370,8 @@ impl Sim {
         let now = self.tick;
         let mut boom: Vec<(DVec3, u32, bool)> = Vec::new();
         let mut removed: Vec<u32> = Vec::new();
-        // Oreshnik pieces released this tick: kind, at, velocity, target.
-        let mut released: Vec<(DroneKind, DVec3, DVec3, DVec3)> = Vec::new();
+        // Oreshnik pieces released this tick: kind, at, velocity, target, the parent's sector (what they teach the enemy).
+        let mut released: Vec<(DroneKind, DVec3, DVec3, DVec3, u8)> = Vec::new();
         // Warheads that reached their aim (for the replays): drone, kind, where, TNT; and splits.
         let mut impacts: Vec<(u32, DroneKind, DVec3, u32)> = Vec::new();
         let mut splits: Vec<(u32, DVec3)> = Vec::new();
@@ -1317,6 +1379,15 @@ impl Sim {
             d.age += 1;
             let spec = d.kind.spec();
             let below = ground.at(d.pos, now);
+            // Near its aim it looks at the land there again: a platform or hilltop blown away
+            // meanwhile, it goes for what is left below, not for the air where it stood.
+            if d.flight != Flight::Falling
+                && horizontal(d.target - d.pos).length() < 250.0
+                && let Some(g) = ground.at(d.target, now)
+                && g < d.target.y - 1.5
+            {
+                d.target.y = g;
+            }
             if d.flight == Flight::Falling {
                 d.vel.y -= 0.05;
                 d.vel *= 0.985;
@@ -1352,7 +1423,7 @@ impl Sim {
                 let speed = d.vel.length();
                 let hit = d.pos.distance(d.target) < speed.max(2.0)
                     || below.is_some_and(|g| d.pos.y <= g + 0.2)
-                    || (d.vel.y < 0.0 && d.pos.y < d.target.y - 1.0)
+                    || (d.vel.y < 0.0 && d.pos.y < d.target.y - 1.0 && horizontal(d.target - d.pos).length() < speed * 2.0)
                     || d.age > 4000;
                 if hit {
                     boom.push((d.pos, spec.warhead, false));
@@ -1377,7 +1448,7 @@ impl Sim {
                         let aim = d.target + DVec3::new(a.sin() * r, 0.0, a.cos() * r);
                         // Straight down at the aim point, at the bus's speed.
                         let v = (aim - d.pos).normalize_or(DVec3::NEG_Y) * 3.0;
-                        released.push((piece, d.pos + v.normalize_or_zero() * (i as f64 * 0.3), v, aim));
+                        released.push((piece, d.pos + v.normalize_or_zero() * (i as f64 * 0.3), v, aim, d.sector));
                     }
                     out.sound("airdef:boom.sonic", d.pos, 1.0, 0.7);
                     splits.push((d.id, d.pos));
@@ -1509,7 +1580,7 @@ impl Sim {
             self.explode(pos, warhead, small, ground, player, out);
         }
         self.drones.retain(|d| !removed.contains(&d.id));
-        for (kind, pos, vel, target) in released {
+        for (kind, pos, vel, target, sector) in released {
             let id = self.id();
             self.drones.push(Drone {
                 id,
@@ -1525,7 +1596,7 @@ impl Sim {
                 route: Vec::new(),
                 low: false,
                 jammed: false,
-                sector: 0,
+                sector,
                 smart: false,
             });
         }
@@ -1624,7 +1695,8 @@ impl Sim {
     }
 
     fn fireball(&mut self, pos: DVec3, size: f64, life: u32) {
-        self.blasts.push(Blast { at: pos, size: size as f32, start: self.tick, life: life * 9 });
+        self.blast_seq = self.blast_seq.wrapping_add(1);
+        self.blasts.push(Blast { id: self.blast_seq, at: pos, size: size as f32, start: self.tick, life: life * 9 });
         if self.blasts.len() > 48 {
             self.blasts.remove(0);
         }
@@ -1688,6 +1760,15 @@ impl Sim {
             return;
         }
         let logistics = self.logistics();
+        // Drones by id (none come or go while the systems act), and how many systems have each as their
+        // missile target and as their gun target: counted once, then kept up to date as targets change.
+        let drone_at: HashMap<u32, usize> = self.drones.iter().enumerate().map(|(k, d)| (d.id, k)).collect();
+        let mut missile_on: HashMap<u32, u32> = HashMap::new();
+        let mut guns_on: HashMap<u32, u32> = HashMap::new();
+        for s in &self.sams {
+            retarget(&mut missile_on, None, s.target);
+            retarget(&mut guns_on, None, s.gun_target);
+        }
         let mut launches: Vec<(MissileKind, DVec3, DVec3, u32, u32)> = Vec::new();
         let mut gun_hits: Vec<(u32, u32)> = Vec::new();
         let mut tracers: Vec<(u32, DVec3, DVec3, u32)> = Vec::new();
@@ -1696,8 +1777,8 @@ impl Sim {
             if !self.sams[i].alive() {
                 let sam = &mut self.sams[i];
                 sam.state = SamState::Destroyed;
-                sam.target = None;
-                sam.gun_target = None;
+                retarget(&mut missile_on, sam.target.take(), None);
+                retarget(&mut guns_on, sam.gun_target.take(), None);
                 continue;
             }
             let fit = self.sams[i].fitness();
@@ -1725,60 +1806,71 @@ impl Sim {
                 sam.state = SamState::Search;
                 // A searchlight's target is its beam's (step_lights): kept for its spot of light.
                 if sam.kind != SamKind::Light {
-                    sam.target = None;
+                    retarget(&mut missile_on, sam.target.take(), None);
                 }
-                sam.gun_target = None;
+                retarget(&mut guns_on, sam.gun_target.take(), None);
                 continue;
             }
             let pos = self.sams[i].pos;
-            let me = self.sams[i].id;
             let roles = self.sams[i].roles;
-            let seen = self.sams[i].seen.clone();
-            let own = self.sams[i].own.clone();
-            let allowed = |d: &Drone| d.alive() && roles & d.kind.spec().class.bit() != 0 && seen.contains(&d.id);
-            // Interceptors a target has or will have: in flight, and other systems' launchers on it.
-            let claimed = |d: &Drone| {
-                d.engaged + self.sams.iter().filter(|s| s.id != me && s.target == Some(d.id)).count() as u32
-            };
-            // Ballistic missiles get a pair; anything else one.
-            let needed = |d: &Drone| if d.kind.spec().class == Class::Ballistic { 2 } else { 1 };
-            if let Some(load) = &spec.missile {
-                let in_reach = |d: &Drone, k: f64| (load.min..load.max * k).contains(&d.pos.distance(pos));
-                let keep = self.sams[i].target.filter(|t| {
-                    self.drones.iter().any(|d| d.id == *t && allowed(d) && in_reach(d, 1.1))
+            let (had_target, had_gun) = (self.sams[i].target, self.sams[i].gun_target);
+            let (target, gun_target) = {
+                let (seen, own) = (&self.sams[i].seen, &self.sams[i].own);
+                let allowed = |d: &Drone| d.alive() && roles & d.kind.spec().class.bit() != 0 && seen.contains(&d.id);
+                // Interceptors a target has or will have: in flight, and other systems' launchers on it.
+                let claimed = |d: &Drone| {
+                    let on = missile_on.get(&d.id).copied().unwrap_or(0) - u32::from(had_target == Some(d.id));
+                    d.engaged + on
+                };
+                // Ballistic missiles get a pair; anything else one.
+                let needed = |d: &Drone| if d.kind.spec().class == Class::Ballistic { 2 } else { 1 };
+                let target = spec.missile.as_ref().map(|load| {
+                    let in_reach = |d: &Drone, k: f64| (load.min..load.max * k).contains(&d.pos.distance(pos));
+                    let keep = had_target.filter(|t| {
+                        drone_at.get(t).is_some_and(|&k| allowed(&self.drones[k]) && in_reach(&self.drones[k], 1.1))
+                    });
+                    keep.or_else(|| {
+                        self.drones
+                            .iter()
+                            .filter(|d| allowed(d) && in_reach(d, 1.0) && claimed(d) < needed(d))
+                            .max_by(|a, b| a.threat(pos).total_cmp(&b.threat(pos)))
+                            .map(|d| d.id)
+                    })
                 });
-                let target = keep.or_else(|| {
+                // Guns: the nearest, spread over the targets the other guns and missiles aren't on.
+                let gun_target = spec.gun.as_ref().map(|gun| {
+                    let on_it = |d: &Drone| {
+                        (guns_on.get(&d.id).copied().unwrap_or(0) - u32::from(had_gun == Some(d.id))) as f64
+                    };
                     self.drones
                         .iter()
-                        .filter(|d| allowed(d) && in_reach(d, 1.0) && claimed(d) < needed(d))
-                        .max_by(|a, b| a.threat(pos).total_cmp(&b.threat(pos)))
-                        .map(|d| d.id)
+                        .filter(|d| allowed(d) && own.contains(&d.id) && d.pos.distance(pos) < gun.track)
+                        .map(|d| {
+                            let busy = 1.0 + 2.0 * on_it(d) + if d.engaged > 0 { 1.5 } else { 0.0 };
+                            (d.pos.distance(pos) * busy, d.id)
+                        })
+                        .min_by(|a, b| a.0.total_cmp(&b.0))
+                        .map(|(_, id)| id)
                 });
+                (target, gun_target)
+            };
+            if let Some(target) = target {
+                retarget(&mut missile_on, had_target, target);
                 self.sams[i].target = target;
             }
-            // Guns: the nearest, spread over the targets the other guns and missiles aren't on.
-            if let Some(gun) = &spec.gun {
-                let guns_on = |d: &Drone| {
-                    self.sams.iter().filter(|s| s.id != me && s.gun_target == Some(d.id)).count() as f64
-                };
-                self.sams[i].gun_target = self
-                    .drones
-                    .iter()
-                    .filter(|d| allowed(d) && own.contains(&d.id) && d.pos.distance(pos) < gun.track)
-                    .map(|d| {
-                        let busy = 1.0 + 2.0 * guns_on(d) + if d.engaged > 0 { 1.5 } else { 0.0 };
-                        (d.pos.distance(pos) * busy, d.id)
-                    })
-                    .min_by(|a, b| a.0.total_cmp(&b.0))
-                    .map(|(_, id)| id);
+            if let Some(gun_target) = gun_target {
+                retarget(&mut guns_on, had_gun, gun_target);
+                self.sams[i].gun_target = gun_target;
             }
             let sam = &mut self.sams[i];
             // What the turret or launcher points at: guns first when a target is close.
-            let aim = sam.gun_target.or(sam.target).and_then(|t| self.drones.iter().find(|d| d.id == t));
+            let aim = sam.gun_target.or(sam.target).and_then(|t| drone_at.get(&t).map(|&k| &self.drones[k]));
             sam.launched = sam.launched.saturating_sub(1);
             let Some(aim) = aim else {
-                // Out of missiles and nothing to shoot: reload now, guns or not.
-                if spec.missile.is_some() && sam.missiles == 0 && sam.reloading == 0 && !sam.empty {
+                // Out of missiles or of shells, and nothing to shoot: reload now (both, as a
+                // combined system's crew would), not only once both are spent.
+                let spent = (spec.missile.is_some() && sam.missiles == 0) || (spec.gun.is_some() && sam.bursts == 0);
+                if spent && sam.reloading == 0 && !sam.empty {
                     if logistics { sam.empty = true } else { sam.reloading = spec.reload }
                 }
                 sam.state = if sam.reloading > 0 {
@@ -1788,8 +1880,8 @@ impl Sim {
                 } else {
                     SamState::Search
                 };
-                sam.yaw = slew(sam.yaw, sam.heading, 0.03);
-                sam.pitch += (spec.rest_pitch - sam.pitch) * 0.05;
+                // Back to the rest position, under the drive's limits like any other turn.
+                sam.aim_towards(sam.heading, Some(spec.rest_pitch));
                 continue;
             };
             let (mount, _) = sam.mount();
@@ -1798,21 +1890,21 @@ impl Sim {
             let to = lead - mount;
             let want_yaw = heading_of(to);
             let want_pitch = (to.y / to.length().max(0.01)).asin().clamp(-0.1, 1.45);
-            let (yaw_rate, pitch_rate) = spec.gun.as_ref().map_or((0.05, 0.05), |g| g.slew);
-            let (yaw_rate, pitch_rate) = (yaw_rate * fit, pitch_rate * fit);
             let cells = matches!(spec.muzzle, Muzzle::Cells);
             match spec.family {
                 // Vertical launch: no aiming (the Tor's turret turns its radar to the target).
-                Family::Vertical if cells => sam.yaw = slew(sam.yaw, want_yaw, 0.15 * fit),
+                Family::Vertical if cells => sam.aim_towards(want_yaw, None),
                 Family::Vertical => {}
-                Family::Trainable => sam.yaw = slew(sam.yaw, want_yaw, 0.12 * fit),
-                _ => {
-                    sam.yaw = slew(sam.yaw, want_yaw, yaw_rate);
-                    sam.pitch = slew(sam.pitch, want_pitch, pitch_rate);
-                }
+                // The launcher's elevation is fixed (the missile turns after its boost): only the training is aimed.
+                Family::Trainable => sam.aim_towards(want_yaw, None),
+                _ => sam.aim_towards(want_yaw, Some(want_pitch)),
             }
-            let aim_error = angle_diff(sam.yaw, want_yaw).abs()
-                + if spec.gun.is_some() { (want_pitch - sam.pitch).abs() } else { 0.0 };
+            // How far the mount still is from the aim, over the axes this family aims.
+            let yaw_error = angle_diff(sam.yaw, want_yaw).abs();
+            let aim_error = match spec.family {
+                Family::Trainable | Family::Vertical => yaw_error,
+                _ => yaw_error + (want_pitch - sam.pitch).abs(),
+            };
             let vertical = spec.family == Family::Vertical;
             sam.state = if sam.reloading > 0 {
                 SamState::Reload
@@ -1831,7 +1923,7 @@ impl Sim {
             };
             // Guns.
             if let (Some(gun), Some(gt)) = (&spec.gun, sam.gun_target) {
-                if let Some(t) = self.drones.iter().find(|d| d.id == gt) {
+                if let Some(t) = drone_at.get(&gt).map(|&k| &self.drones[k]) {
                     let dist = t.pos.distance(mount);
                     if aim.id == gt && aim_error < 0.1 && dist < gun.range && sam.gun_cooldown == 0 && sam.reloading == 0 && sam.bursts > 0 {
                         sam.gun_cooldown = 2;
@@ -1879,11 +1971,11 @@ impl Sim {
                 let ready = sam.cooldown == 0 && sam.reloading == 0 && sam.missiles > 0;
                 let aligned = match spec.family {
                     Family::Trainable => {
-                        let t = self.drones.iter().find(|d| d.id == mt);
-                        // The missile turns after its boost: the launcher needn't be exact.
-                        t.is_some_and(|t| angle_diff(sam.yaw, heading_of(t.pos - mount)).abs() < 0.45)
+                        let t = drone_at.get(&mt).map(|&k| &self.drones[k]);
+                        // The missile turns after its boost, but the launcher must point near the target.
+                        t.is_some_and(|t| angle_diff(sam.yaw, heading_of(t.pos - mount)).abs() < 0.15)
                     }
-                    Family::Turret => aim.id == mt && aim_error < 0.2,
+                    Family::Turret => aim.id == mt && aim_error < 0.15,
                     _ => true,
                 };
                 if ready && aligned {
@@ -1892,10 +1984,11 @@ impl Sim {
                     launches.push((load.kind, muzzle, dir, mt, sam.id));
                     // Its missile is on it from now, so the systems after this one this tick see
                     // the target taken; this one's next launch looks for another.
-                    if let Some(d) = self.drones.iter_mut().find(|d| d.id == mt) {
-                        d.engaged += 1;
+                    if let Some(&k) = drone_at.get(&mt) {
+                        self.drones[k].engaged += 1;
                     }
                     sam.target = None;
+                    retarget(&mut missile_on, Some(mt), None);
                     sam.launched = 12;
                     sam.missiles -= 1;
                     sam.fired += 1;

airdef-mod/src/sim/orders.rs

@@ -56,6 +56,10 @@ impl Sim {
                 continue;
             }
             let spec = sam.kind.spec();
+            // The march and the packing drive the mount themselves: no speed carries over into or out of them.
+            if matches!(sam.state, SamState::Packing | SamState::Moving | SamState::Deploying) {
+                sam.halt_mount();
+            }
             match sam.state {
                 SamState::Packing => {
                     // The launcher comes down for the march.

airdef-mod/src/sim/raid.rs

@@ -98,20 +98,20 @@ pub(super) struct WaveStats {
 }
 
 /// The planner's grid: cells this big, at most this many a side.
-const CELL: f64 = 16.0;
-const CELLS: i32 = 140;
+pub(super) const CELL: f64 = 16.0;
+pub(super) const CELLS: i32 = 140;
 /// The planner's work a tick (cells priced and opened): a raid takes a few ticks to plan, never a long one.
-const WORK_PER_TICK: usize = 40_000;
+pub(super) const WORK_PER_TICK: usize = 40_000;
 
 /// The planner's grid over a raid: its corner, its cells' size and how many a side.
-struct Grid {
-    min: DVec3,
-    cell: f64,
-    size: i32,
+pub(super) struct Grid {
+    pub(super) min: DVec3,
+    pub(super) cell: f64,
+    pub(super) size: i32,
 }
 
 impl Grid {
-    fn index(&self, p: DVec3) -> (i32, i32) {
+    pub(super) fn index(&self, p: DVec3) -> (i32, i32) {
         let n = self.size;
         ((((p.x - self.min.x) / self.cell) as i32).clamp(0, n - 1), (((p.z - self.min.z) / self.cell) as i32).clamp(0, n - 1))
     }
@@ -121,7 +121,7 @@ impl Grid {
 }
 
 /// The cheapest way over `grid` from `from` to `to` by its prices (A*): points along it, `to` last.
-fn plan_route(grid: &Grid, prices: &[f32], from: DVec3, to: DVec3) -> (Vec<DVec3>, usize) {
+pub(super) fn plan_route(grid: &Grid, prices: &[f32], from: DVec3, to: DVec3) -> (Vec<DVec3>, usize) {
     let mut opened = 0;
     let n = grid.size;
     let at = |(i, j): (i32, i32)| (i * n + j) as usize;
@@ -401,7 +401,7 @@ impl Sim {
 
     /// The price of each cell of `grid` for this kind flying low: 1, and much more where a
     /// system sees it there (its radar's reach for it, the land) and can shoot it.
-    fn price_grid(&self, grid: &Grid, kind: DroneKind) -> (Vec<f32>, usize) {
+    pub(super) fn price_grid(&self, grid: &Grid, kind: DroneKind) -> (Vec<f32>, usize) {
         let mut cost = 0;
         let spec = kind.spec();
         let height = spec.clearance.max(6.0);
@@ -426,8 +426,16 @@ impl Sim {
             let sp = s.kind.spec();
             let (lo, hi) = sp.missile.as_ref().map_or((0.0, 0.0), |m| (m.min, m.max));
             let gun = sp.gun.as_ref().map_or(0.0, |g| g.range);
-            let radar = sight::reach(s, kind, height);
-            let far = hi.max(gun).min(radar);
+            // A gun needs its own radar; a missile also flies on the tracks of any radar within data-link range.
+            let own = sight::reach(s, kind, height);
+            let net = self
+                .sams
+                .iter()
+                .filter(|r| r.alive() && r.id != s.id && r.pos.distance(s.pos) <= sight::LINK)
+                .map(|r| sight::reach(r, kind, height))
+                .fold(0.0, f64::max);
+            let (hi, gun) = (hi.min(own.max(net)), gun.min(own));
+            let far = hi.max(gun);
             let at = sight::antenna(s);
             let horizon = self.horizons.get(&s.id);
             // Only the cells round it.

airdef-mod/src/sim/regress.rs

@@ -0,0 +1,224 @@
+//! Regression tests for the issues filed on Gitea (each names its issue).
+use super::*;
+use super::raid::Grid;
+
+// #1: [bug] Запросы рельефа голодают: часть направлений РЛС никогда не получает высоты
+#[test]
+fn terrain_queries_must_eventually_cover_all_radar_bearings() {
+        let mut sim=Sim::new(1);
+        for i in 0..10 {
+            let id=sim.id();sim.sams.push(Sam::new(id,SamKind::Radar,DVec3::new(i as f64*5000.,70.,0.),0.));
+        }
+        let mut ground=Ground::default();
+        for now in 1..=2500 {
+            sim.tick=now;sim.update_sight(&mut ground);
+            let answers=ground.take_wanted().into_iter().map(|(x,z)|(x,z,200)).collect();
+            ground.answer(answers,now);
+        }
+        let visible:Vec<usize>=sim.horizons.values().map(|h|h.rays.iter().filter(|r|r.last().is_some_and(|v|v.is_finite())).count()).collect();
+        eprintln!("radar terrain coverage after 125 seconds: {:?} / 48 bearings each",visible);
+        assert!(visible.iter().all(|n|*n==48),"refreshes of early rays starve unknown terrain in later rays");
+    }
+
+// #2: [bug] Уничтоженная ТЗМ навсегда резервирует заявку на подвоз боеприпасов
+#[test]
+fn dead_truck_must_not_reserve_a_waiting_system() {
+        let mut sim=Sim::new(1);
+        let depot=sim.id(); sim.sams.push(Sam::new(depot,SamKind::Depot,DVec3::new(500.,70.,0.),0.));
+        let target=sim.id(); let mut s=Sam::new(target,SamKind::Tor,DVec3::new(0.,70.,0.),0.);s.empty=true;s.missiles=0;sim.sams.push(s);
+        let dead=sim.id();let mut s=Sam::new(dead,SamKind::Tzm,DVec3::new(100.,70.,0.),0.);s.job=Some(target);s.health=0.;sim.sams.push(s);
+        let live=sim.id();sim.sams.push(Sam::new(live,SamKind::Tzm,DVec3::new(30.,70.,0.),0.));
+        sim.tick=3;sim.step_supply(&mut Out::default());
+        assert_eq!(sim.sams[3].job,Some(target),"a live loaded truck must take the waiting system");
+    }
+
+// #3: [bug] ТЗМ застревает, если обслуживаемая установка сменила позицию
+#[test]
+fn truck_must_follow_a_target_that_moved_away() {
+        let mut sim=Sim::new(1);
+        let depot=sim.id();sim.sams.push(Sam::new(depot,SamKind::Depot,DVec3::new(500.,70.,0.),0.));
+        let target=sim.id();let mut s=Sam::new(target,SamKind::Tor,DVec3::new(100.,70.,0.),0.);s.empty=true;s.missiles=0;sim.sams.push(s);
+        let truck=sim.id();let mut s=Sam::new(truck,SamKind::Tzm,DVec3::new(0.,70.,0.),0.);s.job=Some(target);sim.sams.push(s);
+        sim.tick=2;sim.step_supply(&mut Out::default());
+        assert!(sim.sams[2].moving(),"truck at obsolete rendezvous must get a new move order");
+    }
+
+// #4: [bug] Планировщик умного налёта не учитывает пусковую с внешним целеуказанием
+#[test]
+fn network_launcher_must_contribute_to_route_risk() {
+        let mut sim=Sim::new(1);
+        let id=sim.id();sim.sams.push(Sam::new(id,SamKind::P1sun,DVec3::new(0.,70.,0.),0.));
+        let id=sim.id();sim.sams.push(Sam::new(id,SamKind::Radar,DVec3::new(0.,70.,0.),0.));
+        let grid=Grid{min:DVec3::new(-160.,0.,-160.),cell:16.,size:20};
+        let (prices,_)=sim.price_grid(&grid,DroneKind::Shahed);
+        assert!(prices.iter().any(|p|*p>1.),"armed launcher with a network radar is invisible to route risk");
+    }
+
+// #5: [bug] После ремонта комплекс снова уничтожается от собственной отложенной детонации
+#[test]
+fn repair_must_cancel_pending_magazine_explosions() {
+        let mut sim=Sim::new(1);
+        let id=sim.id();sim.sams.push(Sam::new(id,SamKind::Patriot,DVec3::new(0.,70.,0.),0.));
+        sim.blast_damage(DVec3::new(0.,70.,0.),4,&mut Out::default());
+        assert!(!sim.later.is_empty());sim.repair();
+        sim.tick=3; sim.step_later(&mut Ground::default(),None,&mut Out::default());
+        assert!(sim.sams[0].alive(),"a fully repaired launcher was destroyed again by its own pre-repair cook-off");
+    }
+
+// #34: drones and ballistic missiles burst where their target's platform used to be.
+#[test]
+fn munitions_must_go_down_to_the_land_left_under_a_destroyed_target() {
+    for (kind, from, vel) in [
+        (DroneKind::Shahed, DVec3::new(0.0, 121.0, 0.0), DVec3::ZERO),
+        (DroneKind::OreshnikSub, DVec3::new(0.0, 124.0, 0.0), DVec3::ZERO),
+        (DroneKind::Iskander, DVec3::new(100.0, 121.0, 0.0), DVec3::new(0.0, -4.0, 0.0)),
+    ] {
+        let mut sim = Sim::new(1);
+        sim.damage = false;
+        let mut ground = Ground::default();
+        // The land under the old platform (at y 120) is at 64 now.
+        for x in -120..=120 {
+            for z in -8..=8 {
+                ground.answer(vec![(x, z, 64)], 0);
+            }
+        }
+        sim.add_drone(kind, from, DVec3::NEG_Y, DVec3::new(0.0, 120.0, 0.0));
+        if vel != DVec3::ZERO {
+            sim.drones[0].vel = vel;
+            sim.drones[0].flight = Flight::Ballistic;
+        }
+        let mut out = Out::default();
+        for _ in 0..400 {
+            if sim.drones.is_empty() {
+                break;
+            }
+            sim.step(&mut ground, None, &mut out);
+        }
+        let blast = sim.blasts.first().map(|b| b.at);
+        assert!(blast.is_some_and(|b| b.y < 80.0), "{kind:?} burst at {blast:?}, in the air over the land");
+    }
+}
+
+// #15: lights of blasts in one tick at the same whole X must stay apart
+#[test]
+fn blasts_in_one_tick_have_their_own_ids() {
+    let mut sim = Sim::new(1);
+    sim.tick = 100;
+    sim.fireball(DVec3::new(0.0, 70.0, 100.0), 4.0, 10);
+    sim.fireball(DVec3::new(0.0, 70.0, 200.0), 4.0, 10);
+    assert_ne!(sim.blasts[0].id, sim.blasts[1].id);
+    // A blast going away does not hand its id to the next one.
+    let gone = sim.blasts.remove(0).id;
+    sim.fireball(DVec3::new(0.0, 70.0, 300.0), 4.0, 10);
+    assert!(sim.blasts.iter().all(|b| b.id != gone));
+}
+
+// #21: a smart drone sent at a new target gets a route again, not a straight line
+#[test]
+fn retargeted_smart_drone_gets_a_route_round_the_defences() {
+    let mut sim = Sim::new(1);
+    // A system in the way, between the drone and the unit it is sent at.
+    let id = sim.id();
+    sim.sams.push(Sam::new(id, SamKind::Patriot, DVec3::new(0.0, 70.0, 0.0), 0.0));
+    let id = sim.id();
+    sim.sams.push(Sam::new(id, SamKind::Radar, DVec3::new(0.0, 70.0, 0.0), 0.0));
+    let goal = sim.id();
+    sim.sams.push(Sam::new(goal, SamKind::Ew, DVec3::new(0.0, 70.0, 1000.0), 0.0));
+    sim.intel.revealed.push((goal, DVec3::new(0.0, 70.0, 1000.0), 0));
+    // Its first target, a system that is destroyed by now.
+    let id = sim.id();
+    let mut wreck = Sam::new(id, SamKind::Patriot, DVec3::new(3000.0, 70.0, -1000.0), 0.0);
+    wreck.health = 0.0;
+    sim.sams.push(wreck);
+    sim.add_drone(DroneKind::Shahed, DVec3::new(0.0, 100.0, -1000.0), DVec3::Z, DVec3::new(3000.0, 70.0, -1000.0));
+    sim.drones[0].pos = DVec3::new(0.0, 100.0, -1000.0);
+    sim.drones[0].smart = true;
+    sim.tick = 40;
+    sim.adapt();
+    let d = &sim.drones[0];
+    assert!(d.target.distance(DVec3::new(0.0, 70.0, 1000.0)) < 1.0, "not sent at the unit");
+    assert!(d.route.len() > 1, "no route after the new target: it flies straight through the defences");
+}
+
+// #31: a big cache of fresh columns is not scanned on every answer
+#[test]
+fn big_ground_cache_is_swept_rarely() {
+    let mut ground = Ground::default();
+    ground.known.extend((0..300_001).map(|x| ((x, 0), (64, 2000))));
+    ground.known.insert((-1, 0), (64, 0));
+    // The first answer past the threshold sweeps what is stale and keeps what is fresh.
+    ground.answer(vec![(-2, 0, 64)], 2100);
+    assert!(!ground.known.contains_key(&(-1, 0)), "a stale column was never swept");
+    assert!(ground.known.len() > 300_000);
+    // The next ones wait their pause: a stale column added now survives them.
+    ground.known.insert((-1, 0), (64, 0));
+    let swept = ground.swept;
+    ground.answer(vec![(-3, 0, 64)], 2101);
+    assert_eq!(ground.swept, swept, "swept again at once");
+    assert!(ground.known.contains_key(&(-1, 0)));
+    ground.answer(vec![(-4, 0, 64)], 2100 + SWEEP_EVERY);
+    assert!(!ground.known.contains_key(&(-1, 0)), "never swept again");
+}
+
+// #32: the pieces of an Oreshnik teach the enemy about the sector it came from
+#[test]
+fn oreshnik_pieces_keep_the_sector() {
+    let mut sim = Sim::new(1);
+    sim.add_drone(DroneKind::Oreshnik, DVec3::new(100.0, 300.0, 0.0), DVec3::NEG_Y, DVec3::new(0.0, 70.0, 0.0));
+    sim.drones[0].vel = DVec3::new(-1.0, -1.0, 0.0);
+    sim.drones[0].sector = 7;
+    let mut out = Out::default();
+    sim.step_drones(&mut Ground::default(), None, &mut out);
+    let pieces: Vec<_> = sim.drones.iter().filter(|d| d.kind == DroneKind::OreshnikBlock).collect();
+    assert_eq!(pieces.len(), 6);
+    assert!(pieces.iter().all(|d| d.sector == 7));
+}
+
+// #33: a turret does not fire before it has turned to the target
+#[test]
+fn turret_waits_for_its_aim() {
+    let mut sim = Sim::new(1);
+    let id = sim.id();
+    let mut s = Sam::new(id, SamKind::Gepard, DVec3::new(0.0, 70.0, 0.0), 0.0);
+    s.cooldown = 0;
+    sim.sams.push(s);
+    let id = sim.id();
+    sim.sams.push(Sam::new(id, SamKind::Radar, DVec3::new(0.0, 70.0, 0.0), 0.0));
+    // Straight behind the turret's heading, a slow target well inside the gun's reach.
+    sim.add_drone(DroneKind::Shahed, DVec3::new(0.0, 75.0, 60.0), DVec3::ZERO, DVec3::new(0.0, 70.0, 900.0));
+    sim.drones[0].vel = DVec3::ZERO;
+    let (mut ground, mut out) = (Ground::default(), Out::default());
+    let mut turned = 0;
+    for _ in 0..200 {
+        sim.step(&mut ground, None, &mut out);
+        let g = &sim.sams[0];
+        let want = heading_of(sim.drones[0].pos - g.mount().0);
+        if angle_diff(g.yaw, want).abs() > 0.1 {
+            assert_eq!(g.bursts, 160, "fired with the turret still turning");
+            turned += 1;
+        }
+        if g.bursts < 160 || sim.drones.is_empty() {
+            break;
+        }
+    }
+    assert!(turned > 20, "the turret turned too fast to tell ({turned} ticks)");
+    assert!(sim.sams[0].bursts < 160, "never fired");
+}
+
+// #33: the drive speeds up, brakes in time and does not overshoot
+#[test]
+fn drive_arrives_without_overshoot() {
+    for err in [std::f64::consts::PI, 1.57, 0.3, 0.02] {
+        let (mut vel, mut left) = (0.0, err);
+        let (speed, accel) = (0.088, 0.011);
+        let mut ticks = 0;
+        while left > 0.0 {
+            let step = drive(&mut vel, left, speed, accel);
+            assert!(step.abs() <= speed + 1e-9 && step >= 0.0, "step {step} at {left} left");
+            left -= step;
+            ticks += 1;
+            assert!(ticks < 400, "never arrived for {err}");
+        }
+        assert!(left.abs() < 1e-9 && vel == 0.0);
+    }
+}

airdef-mod/src/sim/sight.rs

@@ -17,7 +17,7 @@ const NEAR: f64 = 24.0;
 
 pub(super) struct Horizon {
     /// Per ray, per sample out: the steepest rise of the land so far (tan of its elevation).
-    rays: Vec<Vec<f32>>,
+    pub(super) rays: Vec<Vec<f32>>,
 }
 
 impl Horizon {
@@ -90,7 +90,8 @@ impl Sim {
                 self.horizons.insert(sam.id, h);
             }
         }
-        self.horizons.retain(|id, _| self.sams.iter().any(|s| s.id == *id && s.alive()));
+        let alive: std::collections::HashSet<u32> = self.sams.iter().filter(|s| s.alive()).map(|s| s.id).collect();
+        self.horizons.retain(|id, _| alive.contains(id));
         // Each drone's height over the land under it (or over the systems' ground, unknown).
         let heights: Vec<Option<f64>> =
             self.drones.iter().map(|d| ground.at(d.pos, now).map(|g| d.pos.y - g)).collect();
@@ -120,18 +121,20 @@ impl Sim {
         // The network: every unit gets the tracks of the radars within data-link range.
         let tracks: Vec<(DVec3, Vec<u32>)> =
             self.sams.iter().filter(|s| !s.own.is_empty()).map(|s| (s.pos, s.own.clone())).collect();
+        // Merged in the radars' order, each track once: a set marks what is in already.
+        let mut have: std::collections::HashSet<u32> = std::collections::HashSet::new();
         for sam in &mut self.sams {
+            sam.seen.clone_from(&sam.own);
             if !sam.alive() || sam.moving() || !sam.kind.armed() {
-                sam.seen = sam.own.clone();
                 continue;
             }
-            let mut seen = sam.own.clone();
+            have.clear();
+            have.extend(sam.own.iter().copied());
             for (at, ids) in &tracks {
                 if at.distance(sam.pos) <= LINK {
-                    seen.extend(ids.iter().copied().filter(|id| !seen.contains(id)).collect::<Vec<_>>());
+                    sam.seen.extend(ids.iter().copied().filter(|id| have.insert(*id)));
                 }
             }
-            sam.seen = seen;
         }
     }
 

airdef-mod/src/sim/units.rs

@@ -99,6 +99,19 @@ pub(super) struct GunSpec {
     pub slew: (f64, f64),
 }
 
+/// How fast a weapon's mount turns: per axis the top speed (radians a tick) and the acceleration, which
+/// is also the braking (radians a tick²). Game settings, not the real machines' figures.
+#[derive(Clone, Copy)]
+pub(super) struct Drive {
+    pub yaw: (f64, f64),
+    pub pitch: (f64, f64),
+}
+
+/// The drives are this share of the speeds they had before they had a speed of their own.
+const DRIVE_SCALE: f64 = 0.4;
+/// Ticks a drive takes to reach its top speed (and to stop from it).
+const DRIVE_RAMP: f64 = 8.0;
+
 pub struct SamSpec {
     pub name: &'static str,
     pub key: &'static str,
@@ -122,6 +135,20 @@ pub struct SamSpec {
     pub mast: f64,
 }
 
+impl SamSpec {
+    /// The mount's drive: the guns' own slew rates, the old rates of the launchers, scaled down.
+    pub(super) fn drive(&self) -> Drive {
+        let (yaw, pitch) = match (&self.gun, self.family) {
+            (Some(g), _) => g.slew,
+            (None, Family::Trainable) => (0.12, 0.0),
+            (None, Family::Vertical) => (0.15, 0.0),
+            (None, _) => (0.05, 0.05),
+        };
+        let axis = |speed: f64| (speed * DRIVE_SCALE, speed * DRIVE_SCALE / DRIVE_RAMP);
+        Drive { yaw: axis(yaw), pitch: axis(pitch) }
+    }
+}
+
 const NO_PARTS: Parts = Parts { body: "", launcher: None, pack: None, dish: None, fixed: &[], spinner: None };
 /// The battery radar trailer behind a vertical launcher.
 const BATTERY_RADAR: &[(&str, f64, f64)] = &[("airdef:radar_trailer", 0.0, 4.2)];

docs/INSTALL.md

@@ -55,7 +55,7 @@ cd ~/Downloads/airdef-macos-arm64
 
 ```powershell
 rustup target add wasm32-unknown-unknown
-git clone ssh://git@gitea.maoniao.team:2222/chexit/airdef.git
+git clone https://gitea.maoniao.team/chexit/airdef.git
 cd airdef
 py tools\airdef.py all          # форк Horizon + сборка игры + мод + установка мода
 py tools\airdef.py play         # запуск; мир: py tools\airdef.py play --world "Имя мира"
@@ -69,12 +69,14 @@ py tools\airdef.py play         # запуск; мир: py tools\airdef.py play
 
 ```sh
 rustup target add wasm32-unknown-unknown
-git clone ssh://git@gitea.maoniao.team:2222/chexit/airdef.git
+git clone https://gitea.maoniao.team/chexit/airdef.git
 cd airdef
 python3 tools/airdef.py all
 python3 tools/airdef.py play    # или: python3 tools/airdef.py play --world "Имя мира"
 ```
 
+Клон по HTTPS не требует ключа. Если у тебя есть SSH-ключ в Gitea, можно и так: `git clone ssh://git@gitea.maoniao.team:2222/chexit/airdef.git`.
+
 Шаги по отдельности: `fork` (скачать Horizon и наложить патчи `horizon-patches/`), `game` (собрать игру),
 `mod` (собрать `airdef.hmod`), `install` (положить мод в папку игры и включить), `play`.
 

horizon-patches/0001-Mod-API-AirDef-fork-world-models-client-particles-so.patch

@@ -1,7 +1,7 @@
 From 3de7a6875140a107e28563cc44489b55f5794517 Mon Sep 17 00:00:00 2001
 From: chexit <chexit@duck.com>
 Date: Wed, 28 Oct 2026 12:37:45 +0300
-Subject: [PATCH 01/12] Mod API (AirDef fork): world models, client particles,
+Subject: [PATCH 01/14] Mod API (AirDef fork): world models, client particles,
  sounds, ground heights
 
 render.set-models draws block models with an interpolated pose per id;

horizon-patches/0002-cargo-horizon-mod-report-particles-and-sounds.patch

@@ -1,7 +1,7 @@
 From a6d64e6415bf618539af464e521091e72b72d72f Mon Sep 17 00:00:00 2001
 From: chexit <chexit@duck.com>
 Date: Wed, 28 Oct 2026 12:39:45 +0300
-Subject: [PATCH 02/12] cargo-horizon-mod: report particles and sounds
+Subject: [PATCH 02/14] cargo-horizon-mod: report particles and sounds
 
 Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
 ---

horizon-patches/0003-Mod-API-AirDef-fork-full-screen-post-pass-for-mods.patch

@@ -1,7 +1,7 @@
 From ee79b3562feebe51959a01f1585a9e85bd53ccb5 Mon Sep 17 00:00:00 2001
 From: chexit <chexit@duck.com>
 Date: Wed, 28 Oct 2026 13:33:10 +0300
-Subject: [PATCH 03/12] Mod API (AirDef fork): full-screen post pass for mods
+Subject: [PATCH 03/14] Mod API (AirDef fork): full-screen post pass for mods
 
 render.set-post compiles a mod's WGSL after a prelude (camera matrices,
 time, 256 vec4 of params, the world's colour and depth) and runs it after

horizon-patches/0004-Mod-models-draw-far-models-as-scaled-impostors-past-.patch

@@ -1,7 +1,7 @@
 From 2b137dbbedd540daeebc7f5e387847aeb56a1355 Mon Sep 17 00:00:00 2001
 From: chexit <chexit@duck.com>
 Date: Wed, 28 Oct 2026 22:09:30 +0300
-Subject: [PATCH 04/12] Mod models: draw far models as scaled impostors past
+Subject: [PATCH 04/14] Mod models: draw far models as scaled impostors past
  the far plane, cull at 4096
 
 ---

horizon-patches/0005-Mod-cameras-render.set-views-draws-the-world-from-ot.patch

@@ -1,7 +1,7 @@
 From c8ebca6e0af68630e65211844b34d25c5b985c03 Mon Sep 17 00:00:00 2001
 From: chexit <chexit@duck.com>
 Date: Wed, 28 Oct 2026 22:31:00 +0300
-Subject: [PATCH 05/12] Mod cameras: render.set-views draws the world from
+Subject: [PATCH 05/14] Mod cameras: render.set-views draws the world from
  other points into pictures that HUD view shapes show (API level 9)
 
 Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

horizon-patches/0006-Mods-more-fuel-per-tick-and-per-event-AirDef-plans-r.patch

@@ -1,7 +1,7 @@
 From 8d2261fc4f8072c32e454139cfea7a8c0cd9d664 Mon Sep 17 00:00:00 2001
 From: chexit <chexit@duck.com>
 Date: Wed, 28 Oct 2026 23:08:21 +0300
-Subject: [PATCH 06/12] Mods: more fuel per tick and per event (AirDef plans
+Subject: [PATCH 06/14] Mods: more fuel per tick and per event (AirDef plans
  raids)
 
 Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

horizon-patches/0007-Mod-cameras-up-to-1920x1080-full-screen-replays.patch

@@ -1,7 +1,7 @@
 From 6c548de34def8e4a624d734243418090798bd16a Mon Sep 17 00:00:00 2001
 From: chexit <chexit@duck.com>
 Date: Wed, 28 Oct 2026 23:25:29 +0300
-Subject: [PATCH 07/12] Mod cameras up to 1920x1080 (full-screen replays)
+Subject: [PATCH 07/14] Mod cameras up to 1920x1080 (full-screen replays)
 
 Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
 ---

horizon-patches/0008-Mod-cameras-distant-terrain-tiles-fog-measured-from-.patch

@@ -1,7 +1,7 @@
 From 9b9e93269d67401cc620567a884d5ce97f68d76e Mon Sep 17 00:00:00 2001
 From: chexit <chexit@duck.com>
 Date: Thu, 29 Oct 2026 11:15:11 +0300
-Subject: [PATCH 08/12] Mod cameras: distant terrain tiles, fog measured from
+Subject: [PATCH 08/14] Mod cameras: distant terrain tiles, fog measured from
  the camera, no impostors while one is shown
 
 Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

horizon-patches/0009-Mods-game.world-id-so-mods-keep-state-per-world-API-.patch

@@ -1,7 +1,7 @@
 From 065d9fa02966238a5bd9ff460392a1a809db0b11 Mon Sep 17 00:00:00 2001
 From: chexit <chexit@duck.com>
 Date: Thu, 29 Oct 2026 11:25:45 +0300
-Subject: [PATCH 09/12] Mods: game.world-id, so mods keep state per world (API
+Subject: [PATCH 09/14] Mods: game.world-id, so mods keep state per world (API
  level 9)
 
 Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

horizon-patches/0010-cargo-horizon-mod-trial-runs-behind-feature-full-so-.patch

@@ -1,7 +1,7 @@
 From 1bf28135fd9a31f837323dc3a8d81ed73343d816 Mon Sep 17 00:00:00 2001
 From: chexit <chexit@duck.com>
 Date: Thu, 29 Oct 2026 12:01:08 +0300
-Subject: [PATCH 10/12] cargo-horizon-mod: trial runs behind feature full, so a
+Subject: [PATCH 10/14] cargo-horizon-mod: trial runs behind feature full, so a
  packing-only tool skips wasmtime
 
 Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

horizon-patches/0011-HD-lighting-G-buffer-pass-per-pixel-mod-point-lights.patch

@@ -1,7 +1,7 @@
 From 0a56f5616df4699588cbcc529d4720661baa810f Mon Sep 17 00:00:00 2001
 From: chexit <chexit@duck.com>
 Date: Thu, 29 Oct 2026 13:18:43 +0300
-Subject: [PATCH 11/12] HD lighting: G-buffer pass, per-pixel mod point lights
+Subject: [PATCH 11/14] HD lighting: G-buffer pass, per-pixel mod point lights
  in HDR, bloom and tone curve; render.set-lights and render.set-lighting (API
  level 10)
 

horizon-patches/0012-HD-lighting-stage-2-sun-and-moon-shadow-cascades-the.patch

@@ -1,7 +1,7 @@
 From 9ebf0031fe9ba6b7f02afb26e4fd3a1ba4ddb0d0 Mon Sep 17 00:00:00 2001
 From: chexit <chexit@duck.com>
 Date: Thu, 29 Oct 2026 13:59:43 +0300
-Subject: [PATCH 12/12] HD lighting stage 2: sun and moon shadow cascades, the
+Subject: [PATCH 12/14] HD lighting stage 2: sun and moon shadow cascades, the
  world relit (sun by face angle and shadow, sky and block light through the
  lightmap), light shafts and halos, fog over it again, a light colour grade
 

horizon-patches/0013-HD-bind-groups-cached-until-a-resize-or-a-new-source.patch

@@ -0,0 +1,439 @@
+From 7a5a38f68923aec62f10bfa0df50b436474ed612 Mon Sep 17 00:00:00 2001
+From: chexit <chexit@duck.com>
+Date: Thu, 29 Oct 2026 16:19:53 +0300
+Subject: [PATCH 13/14] HD: bind groups cached until a resize or a new source,
+ shadow passes draw only the entities that cast shadows
+
+Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
+---
+ crates/horizon-client/src/gfx.rs    |  39 ++++-
+ crates/horizon-client/src/gfx/hd.rs | 247 +++++++++++++++++-----------
+ 2 files changed, 188 insertions(+), 98 deletions(-)
+
+diff --git a/crates/horizon-client/src/gfx.rs b/crates/horizon-client/src/gfx.rs
+index e351763fd..f6bbe038c 100644
+--- a/crates/horizon-client/src/gfx.rs
++++ b/crates/horizon-client/src/gfx.rs
+@@ -459,6 +459,8 @@ pub struct Renderer {
+     entity_buffer: wgpu::Buffer,
+     entity_capacity: u64,
+     entity_batch: EntityBatch,
++    /// AirDef fork: the runs of entity quads (first, end) that cast shadows this frame.
++    shadow_casters: Vec<(u32, u32)>,
+     group: wgpu::BindGroup,
+     globals: wgpu::Buffer,
+     lightmap: wgpu::Texture,
+@@ -2744,6 +2746,7 @@ impl Renderer {
+             entity_buffer,
+             entity_capacity,
+             entity_batch: EntityBatch::default(),
++            shadow_casters: Vec::new(),
+             group,
+             globals,
+             lightmap,
+@@ -4980,6 +4983,30 @@ impl Renderer {
+             }
+             // The sun's (or moon's) shadow cascades: the world's globals swapped for the light's.
+             if shadow_strength > 0.0 {
++                // The quads the shadow shader would not discard (overlays 4, 9, 10 and 40:
++                // glowing mod geometry), as runs, so those are not vertex-processed twice.
++                self.shadow_casters.clear();
++                let mut start = None;
++                let quads = self.entity_batch.combined.as_chunks::<4>().0;
++                for (i, quad) in quads.iter().take(entity_quads as usize).enumerate() {
++                    let caster = !matches!(quad[0].layer, 4 | 9 | 10 | 40);
++                    match (caster, start) {
++                        (true, None) => start = Some(i as u32),
++                        (false, Some(first)) => {
++                            self.shadow_casters.push((first, i as u32));
++                            start = None;
++                        }
++                        _ => {}
++                    }
++                }
++                if let Some(first) = start {
++                    self.shadow_casters.push((first, entity_quads));
++                }
++                // Many tiny runs cost more in draw calls than they save: draw everything.
++                if self.shadow_casters.len() > 64 {
++                    self.shadow_casters.clear();
++                    self.shadow_casters.push((0, entity_quads));
++                }
+                 self.queue
+                     .write_buffer(&hd.main_globals, 0, bytemuck::bytes_of(&globals));
+                 for (c, cascade) in hd_cascades.iter().enumerate() {
+@@ -5021,11 +5048,13 @@ impl Renderer {
+                         let instance = hd_shadow_first + k as u32;
+                         pass.draw_indexed(0..s.solid * 6, s.start as i32, instance..instance + 1);
+                     }
+-                    if entity_quads > 0 {
++                    if !self.shadow_casters.is_empty() {
+                         pass.set_pipeline(&self.shadow_entity);
+                         pass.set_bind_group(0, &self.entity_group, &[]);
+                         pass.set_vertex_buffer(0, self.entity_buffer.slice(..));
+-                        pass.draw_indexed(0..entity_quads * 6, 0, 0..1);
++                        for &(first, end) in &self.shadow_casters {
++                            pass.draw_indexed(first * 6..end * 6, 0, 0..1);
++                        }
+                     }
+                 }
+                 encoder.copy_buffer_to_buffer(&hd.main_globals, 0, &self.globals, 0, globals_size);
+@@ -5586,7 +5615,7 @@ impl Renderer {
+             );
+         } else if let Some((color, depth)) = &scaled
+             && hd_on
+-            && let Some(hd) = &self.hd
++            && let Some(hd) = &mut self.hd
+         {
+             // AirDef fork: lit by the mods' lights into the HD target, the mod's post pass on
+             // that, then bloom and the tone curve onto the screen.
+@@ -5607,9 +5636,9 @@ impl Renderer {
+                         self.mod_params.1,
+                     );
+                     post.run(&self.device, &mut encoder, (&hd.lit, depth), &hd.fx);
+-                    hd.finish(&self.device, &mut encoder, &hd.fx, &view_target);
++                    hd.finish(&self.device, &mut encoder, hd::HdSource::Fx, &view_target);
+                 }
+-                _ => hd.finish(&self.device, &mut encoder, &hd.lit, &view_target),
++                _ => hd.finish(&self.device, &mut encoder, hd::HdSource::Lit, &view_target),
+             }
+         } else if let Some((color, depth)) = &scaled
+             && mod_post
+diff --git a/crates/horizon-client/src/gfx/hd.rs b/crates/horizon-client/src/gfx/hd.rs
+index c36c1795d..fe2634f2c 100644
+--- a/crates/horizon-client/src/gfx/hd.rs
++++ b/crates/horizon-client/src/gfx/hd.rs
+@@ -359,6 +359,21 @@ fn target(
+     Target { view }
+ }
+ 
++/// The outside views and sampler the lighting group reads.
++type LightKey = (
++    wgpu::TextureView,
++    wgpu::TextureView,
++    wgpu::TextureView,
++    wgpu::Sampler,
++);
++
++/// What bloom and the tone curve read: the lit world, or the post pass's output.
++#[derive(Clone, Copy, PartialEq, Eq)]
++pub enum HdSource {
++    Lit,
++    Fx,
++}
++
+ pub struct Hd {
+     size: [u32; 2],
+     pub albedo: wgpu::TextureView,
+@@ -377,6 +392,15 @@ pub struct Hd {
+     pub lit: wgpu::TextureView,
+     pub fx: wgpu::TextureView,
+     bloom: Vec<Target>,
++    /// Bind groups, rebuilt only when their views change: `resize` drops all of them, the
++    /// lighting and the source-reading ones are keyed by the views they read.
++    light_group: Option<(LightKey, wgpu::BindGroup)>,
++    prefilter_group: Option<(wgpu::TextureView, wgpu::BindGroup)>,
++    tone_group: Option<(wgpu::TextureView, wgpu::BindGroup)>,
++    /// Reading bloom level k - 1 (for the down pass into level k, index k - 1) and level k (for
++    /// the up pass onto level k - 1, index k - 1).
++    down_groups: Vec<wgpu::BindGroup>,
++    up_groups: Vec<wgpu::BindGroup>,
+     frame: wgpu::Buffer,
+     lights: wgpu::Buffer,
+     sampler: wgpu::Sampler,
+@@ -656,6 +680,11 @@ impl Hd {
+             lit: target(device, "HD lit", [1, 1], HDR).view,
+             fx: target(device, "HD post", [1, 1], HDR).view,
+             bloom: Vec::new(),
++            light_group: None,
++            prefilter_group: None,
++            tone_group: None,
++            down_groups: Vec::new(),
++            up_groups: Vec::new(),
+             frame,
+             lights,
+             sampler,
+@@ -690,6 +719,16 @@ impl Hd {
+                 target(device, "HD bloom", s, HDR)
+             })
+             .collect();
++        // Every group names a view that was just replaced.
++        self.light_group = None;
++        self.prefilter_group = None;
++        self.tone_group = None;
++        self.down_groups = (1..self.bloom.len())
++            .map(|k| self.bloom_group(device, &self.bloom[k - 1].view))
++            .collect();
++        self.up_groups = (1..self.bloom.len())
++            .map(|k| self.bloom_group(device, &self.bloom[k].view))
++            .collect();
+     }
+ 
+     /// This frame's camera, sun, fog, lights and settings.
+@@ -829,73 +868,85 @@ impl Hd {
+ 
+     /// Lights the world (its colour and depth) into `lit`.
+     pub fn light(
+-        &self,
++        &mut self,
+         device: &wgpu::Device,
+         encoder: &mut wgpu::CommandEncoder,
+         world: (&wgpu::TextureView, &wgpu::TextureView),
+         lightmap: (&wgpu::TextureView, &wgpu::Sampler),
+     ) {
+-        let group = device.create_bind_group(&wgpu::BindGroupDescriptor {
+-            label: Some("HD lighting"),
+-            layout: &self.light_layout,
+-            entries: &[
+-                wgpu::BindGroupEntry {
+-                    binding: 0,
+-                    resource: self.frame.as_entire_binding(),
+-                },
+-                wgpu::BindGroupEntry {
+-                    binding: 1,
+-                    resource: wgpu::BindingResource::TextureView(world.0),
+-                },
+-                wgpu::BindGroupEntry {
+-                    binding: 2,
+-                    resource: wgpu::BindingResource::TextureView(world.1),
+-                },
+-                wgpu::BindGroupEntry {
+-                    binding: 3,
+-                    resource: wgpu::BindingResource::TextureView(&self.albedo),
+-                },
+-                wgpu::BindGroupEntry {
+-                    binding: 4,
+-                    resource: wgpu::BindingResource::TextureView(&self.normal),
+-                },
+-                wgpu::BindGroupEntry {
+-                    binding: 5,
+-                    resource: wgpu::BindingResource::TextureView(&self.depth),
+-                },
+-                wgpu::BindGroupEntry {
+-                    binding: 6,
+-                    resource: self.lights.as_entire_binding(),
+-                },
+-                wgpu::BindGroupEntry {
+-                    binding: 7,
+-                    resource: wgpu::BindingResource::TextureView(&self.levels),
+-                },
+-                wgpu::BindGroupEntry {
+-                    binding: 8,
+-                    resource: wgpu::BindingResource::TextureView(&self.shadow_array),
+-                },
+-                wgpu::BindGroupEntry {
+-                    binding: 9,
+-                    resource: wgpu::BindingResource::Sampler(&self.shadow_sampler),
+-                },
+-                wgpu::BindGroupEntry {
+-                    binding: 10,
+-                    resource: wgpu::BindingResource::TextureView(lightmap.0),
+-                },
+-                wgpu::BindGroupEntry {
+-                    binding: 11,
+-                    resource: wgpu::BindingResource::Sampler(lightmap.1),
+-                },
+-            ],
+-        });
++        let key = (
++            world.0.clone(),
++            world.1.clone(),
++            lightmap.0.clone(),
++            lightmap.1.clone(),
++        );
++        if self.light_group.as_ref().is_none_or(|(k, _)| *k != key) {
++            let group = device.create_bind_group(&wgpu::BindGroupDescriptor {
++                label: Some("HD lighting"),
++                layout: &self.light_layout,
++                entries: &[
++                    wgpu::BindGroupEntry {
++                        binding: 0,
++                        resource: self.frame.as_entire_binding(),
++                    },
++                    wgpu::BindGroupEntry {
++                        binding: 1,
++                        resource: wgpu::BindingResource::TextureView(world.0),
++                    },
++                    wgpu::BindGroupEntry {
++                        binding: 2,
++                        resource: wgpu::BindingResource::TextureView(world.1),
++                    },
++                    wgpu::BindGroupEntry {
++                        binding: 3,
++                        resource: wgpu::BindingResource::TextureView(&self.albedo),
++                    },
++                    wgpu::BindGroupEntry {
++                        binding: 4,
++                        resource: wgpu::BindingResource::TextureView(&self.normal),
++                    },
++                    wgpu::BindGroupEntry {
++                        binding: 5,
++                        resource: wgpu::BindingResource::TextureView(&self.depth),
++                    },
++                    wgpu::BindGroupEntry {
++                        binding: 6,
++                        resource: self.lights.as_entire_binding(),
++                    },
++                    wgpu::BindGroupEntry {
++                        binding: 7,
++                        resource: wgpu::BindingResource::TextureView(&self.levels),
++                    },
++                    wgpu::BindGroupEntry {
++                        binding: 8,
++                        resource: wgpu::BindingResource::TextureView(&self.shadow_array),
++                    },
++                    wgpu::BindGroupEntry {
++                        binding: 9,
++                        resource: wgpu::BindingResource::Sampler(&self.shadow_sampler),
++                    },
++                    wgpu::BindGroupEntry {
++                        binding: 10,
++                        resource: wgpu::BindingResource::TextureView(lightmap.0),
++                    },
++                    wgpu::BindGroupEntry {
++                        binding: 11,
++                        resource: wgpu::BindingResource::Sampler(lightmap.1),
++                    },
++                ],
++            });
++            self.light_group = Some((key, group));
++        }
++        let Some((_, group)) = &self.light_group else {
++            return;
++        };
+         Self::draw(
+             encoder,
+             "HD lighting",
+             &self.lit,
+             false,
+             &self.light_pipeline,
+-            &group,
++            group,
+         );
+     }
+ 
+@@ -922,12 +973,53 @@ impl Hd {
+ 
+     /// Bloom from `source` (the lit world or the post pass's output), then the tone curve onto `screen`.
+     pub fn finish(
+-        &self,
++        &mut self,
+         device: &wgpu::Device,
+         encoder: &mut wgpu::CommandEncoder,
+-        source: &wgpu::TextureView,
++        source: HdSource,
+         screen: &wgpu::TextureView,
+     ) {
++        let source = match source {
++            HdSource::Lit => self.lit.clone(),
++            HdSource::Fx => self.fx.clone(),
++        };
++        if self
++            .prefilter_group
++            .as_ref()
++            .is_none_or(|(v, _)| *v != source)
++        {
++            let group = self.bloom_group(device, &source);
++            self.prefilter_group = Some((source.clone(), group));
++        }
++        if self.tone_group.as_ref().is_none_or(|(v, _)| *v != source) {
++            let group = device.create_bind_group(&wgpu::BindGroupDescriptor {
++                label: Some("HD tone mapping"),
++                layout: &self.tone_layout,
++                entries: &[
++                    wgpu::BindGroupEntry {
++                        binding: 0,
++                        resource: self.frame.as_entire_binding(),
++                    },
++                    wgpu::BindGroupEntry {
++                        binding: 1,
++                        resource: wgpu::BindingResource::TextureView(&source),
++                    },
++                    wgpu::BindGroupEntry {
++                        binding: 2,
++                        resource: wgpu::BindingResource::TextureView(&self.bloom[0].view),
++                    },
++                    wgpu::BindGroupEntry {
++                        binding: 3,
++                        resource: wgpu::BindingResource::Sampler(&self.sampler),
++                    },
++                ],
++            });
++            self.tone_group = Some((source, group));
++        }
++        let (Some((_, prefilter)), Some((_, tone))) = (&self.prefilter_group, &self.tone_group)
++        else {
++            return;
++        };
+         // Down: the prefilter into the first level, then each level from the one above.
+         Self::draw(
+             encoder,
+@@ -935,61 +1027,30 @@ impl Hd {
+             &self.bloom[0].view,
+             false,
+             &self.prefilter,
+-            &self.bloom_group(device, source),
++            prefilter,
+         );
+         for k in 1..self.bloom.len() {
+-            let g = self.bloom_group(device, &self.bloom[k - 1].view);
+             Self::draw(
+                 encoder,
+                 "HD bloom down",
+                 &self.bloom[k].view,
+                 false,
+                 &self.down,
+-                &g,
++                &self.down_groups[k - 1],
+             );
+         }
+         // Up: each level added onto the bigger one.
+         for k in (1..self.bloom.len()).rev() {
+-            let g = self.bloom_group(device, &self.bloom[k].view);
+             Self::draw(
+                 encoder,
+                 "HD bloom up",
+                 &self.bloom[k - 1].view,
+                 true,
+                 &self.up,
+-                &g,
++                &self.up_groups[k - 1],
+             );
+         }
+-        let group = device.create_bind_group(&wgpu::BindGroupDescriptor {
+-            label: Some("HD tone mapping"),
+-            layout: &self.tone_layout,
+-            entries: &[
+-                wgpu::BindGroupEntry {
+-                    binding: 0,
+-                    resource: self.frame.as_entire_binding(),
+-                },
+-                wgpu::BindGroupEntry {
+-                    binding: 1,
+-                    resource: wgpu::BindingResource::TextureView(source),
+-                },
+-                wgpu::BindGroupEntry {
+-                    binding: 2,
+-                    resource: wgpu::BindingResource::TextureView(&self.bloom[0].view),
+-                },
+-                wgpu::BindGroupEntry {
+-                    binding: 3,
+-                    resource: wgpu::BindingResource::Sampler(&self.sampler),
+-                },
+-            ],
+-        });
+-        Self::draw(
+-            encoder,
+-            "HD tone mapping",
+-            screen,
+-            false,
+-            &self.tone,
+-            &group,
+-        );
++        Self::draw(encoder, "HD tone mapping", screen, false, &self.tone, tone);
+     }
+ }
+ 
+-- 
+2.54.0 (Apple Git-157)
+

horizon-patches/0014-HD-lights-culled-per-16x16-tile-surface-and-halo-lis.patch

@@ -0,0 +1,362 @@
+From 8020811e57d4b5a9ea1cd72d30ce859dc5095d35 Mon Sep 17 00:00:00 2001
+From: chexit <chexit@duck.com>
+Date: Thu, 29 Oct 2026 16:25:44 +0300
+Subject: [PATCH 14/14] HD: lights culled per 16x16 tile (surface and halo
+ lists built on the CPU), a naga test for the lighting shaders
+
+Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
+---
+ crates/horizon-client/src/gfx/hd.rs | 242 +++++++++++++++++++++++++++-
+ 1 file changed, 236 insertions(+), 6 deletions(-)
+
+diff --git a/crates/horizon-client/src/gfx/hd.rs b/crates/horizon-client/src/gfx/hd.rs
+index fe2634f2c..2776219fc 100644
+--- a/crates/horizon-client/src/gfx/hd.rs
++++ b/crates/horizon-client/src/gfx/hd.rs
+@@ -16,6 +16,12 @@ pub const LIGHT_LEVELS: wgpu::TextureFormat = wgpu::TextureFormat::Rgba8Unorm;
+ pub const HDR: wgpu::TextureFormat = wgpu::TextureFormat::Rgba16Float;
+ /// The most lights drawn a frame.
+ pub const MAX_LIGHTS: usize = 512;
++/// The side (pixels) of a tile of the screen with its own short list of lights.
++const TILE: u32 = 16;
++/// The indices all the tile lists may hold together; a tile past it loops over every light.
++const TILE_INDICES: usize = 1 << 19;
++/// A list length that means "every light": the list overflowed.
++const EVERY_LIGHT: u32 = u32::MAX;
+ /// Bloom's mip levels.
+ const BLOOM_LEVELS: usize = 6;
+ 
+@@ -55,7 +61,7 @@ struct HdFrame {
+     fog: [f32; 4],
+     /// x: sky light kept in the shade; y: blocks' light; z: the air's density (rays, halos).
+     ambient: [f32; 4],
+-    /// x: shadows on; y, z: the cascades' half sizes.
++    /// x: shadows on; y, z: the cascades' half sizes; w: the light tiles per row.
+     shadow: [f32; 4],
+ }
+ 
+@@ -123,6 +129,10 @@ struct Light {
+ @group(0) @binding(9) var shadow_sampler: sampler_comparison;
+ @group(0) @binding(10) var lightmap: texture_2d<f32>;
+ @group(0) @binding(11) var linear: sampler;
++// Per tile of 16x16 pixels: where its surface list and its halo list start in this array and
++// how long they are (4 words), then the lists of light indices. A length of 0xffffffff means
++// every light.
++@group(0) @binding(12) var<storage, read> tiles: array<u32>;
+ 
+ // Interleaved gradient noise: a different offset each pixel and frame, for the ray march.
+ fn ign(px: vec2<f32>) -> f32 {
+@@ -181,6 +191,13 @@ fn fs_light(in: FullOut) -> @location(0) vec4<f32> {
+     let sun = frame.sun.xyz;
+     let sun_on = frame.sun.w;
+     let count = u32(frame.params.x);
++    let tile = ((u32(px.y) >> 4u) * u32(frame.shadow.w) + (u32(px.x) >> 4u)) * 4u;
++    let surface_start = tiles[tile];
++    let surface_all = tiles[tile + 1u] == 0xffffffffu;
++    let surface_count = select(tiles[tile + 1u], count, surface_all);
++    let halo_start = tiles[tile + 2u];
++    let halo_all = tiles[tile + 3u] == 0xffffffffu;
++    let halo_count = select(tiles[tile + 3u], count, halo_all);
+     var c = scene;
+     let surface = d > 0.0 && abs(d - g) <= max(d, g) * 0.002;
+     if surface {
+@@ -199,8 +216,8 @@ fn fs_light(in: FullOut) -> @location(0) vec4<f32> {
+         let direct = frame.sun_color.rgb * sun_on * max(ndl, 0.0) * s * sky_reach;
+         var light = max(base * frame.ambient.x, block * frame.ambient.y) + direct;
+         // The mods' lights.
+-        for (var i = 0u; i < count; i++) {
+-            let l = lights[i];
++        for (var k = 0u; k < surface_count; k++) {
++            let l = lights[select(tiles[surface_start + k], k, surface_all)];
+             let to = l.pos.xyz - p;
+             let dist = length(to);
+             if dist >= l.pos.w { continue; }
+@@ -233,8 +250,8 @@ fn fs_light(in: FullOut) -> @location(0) vec4<f32> {
+         let phase = (1.0 - gk * gk) / pow(1.0 + gk * gk - 2.0 * gk * cos_t, 1.5) * 0.08;
+         c += frame.sun_color.rgb * sun_on * (acc / f32(steps)) * phase * (1.0 - exp(-far * density));
+     }
+-    for (var i = 0u; i < count; i++) {
+-        let l = lights[i];
++    for (var k = 0u; k < halo_count; k++) {
++        let l = lights[select(tiles[halo_start + k], k, halo_all)];
+         // Nearest point of the view ray to the light, and the glow along the ray in front of it.
+         let t0 = dot(l.pos.xyz, view);
+         let hh = length(l.pos.xyz - view * t0) + 0.5;
+@@ -403,6 +420,11 @@ pub struct Hd {
+     up_groups: Vec<wgpu::BindGroup>,
+     frame: wgpu::Buffer,
+     lights: wgpu::Buffer,
++    /// The tiles' light lists (see `tile_lists`), sized for the screen, and the tiles per row.
++    tiles: wgpu::Buffer,
++    tiles_x: u32,
++    tile_scratch: Vec<Vec<u16>>,
++    tile_words: Vec<u32>,
+     sampler: wgpu::Sampler,
+     light_layout: wgpu::BindGroupLayout,
+     light_pipeline: wgpu::RenderPipeline,
+@@ -414,6 +436,137 @@ pub struct Hd {
+     tone: wgpu::RenderPipeline,
+ }
+ 
++/// The tiles' header (4 words each) and index lists for a screen of `size`.
++fn tiles_buffer(device: &wgpu::Device, size: [u32; 2]) -> wgpu::Buffer {
++    let tiles = (size[0].div_ceil(TILE).max(1) * size[1].div_ceil(TILE).max(1)) as usize;
++    device.create_buffer(&wgpu::BufferDescriptor {
++        label: Some("HD light tiles"),
++        size: ((tiles * 4 + TILE_INDICES) * std::mem::size_of::<u32>()) as u64,
++        usage: wgpu::BufferUsages::STORAGE | wgpu::BufferUsages::COPY_DST,
++        mapped_at_creation: false,
++    })
++}
++
++/// Where a camera-relative sphere can show on the screen.
++enum Cover {
++    /// Nowhere: it is wholly behind the camera.
++    Nothing,
++    /// Anywhere: it crosses the camera's plane, or holds the camera.
++    Everywhere,
++    /// Inside this pixel rectangle (min x, min y, max x, max y).
++    Rect([f32; 4]),
++}
++
++/// The screen cover of the sphere at `c` of radius `r`: the projection of the 8 corners of the
++/// box round it. A box is convex and so is its projection while every corner is in front of the
++/// camera, so the rectangle holds the whole sphere. With some corners behind, the projection
++/// is not bounded and the cover is the whole screen; with all of them behind, no pixel ray
++/// (they all point forward) can meet the sphere.
++fn cover(view_proj: &Mat4, c: glam::Vec3, r: f32, size: [u32; 2]) -> Cover {
++    if !c.is_finite() || !r.is_finite() {
++        return Cover::Everywhere;
++    }
++    // A little more than the shader's radius, against rounding.
++    let r = r * 1.01 + 0.01;
++    let (mut lo, mut hi) = (glam::Vec2::splat(f32::MAX), glam::Vec2::splat(f32::MIN));
++    let mut front = 0;
++    for corner in 0..8 {
++        let o = glam::Vec3::new(
++            if corner & 1 == 0 { -r } else { r },
++            if corner & 2 == 0 { -r } else { r },
++            if corner & 4 == 0 { -r } else { r },
++        );
++        let h = *view_proj * (c + o).extend(1.0);
++        if h.w > 0.0 {
++            front += 1;
++            let ndc = glam::Vec2::new(h.x, h.y) / h.w;
++            let px = glam::Vec2::new(
++                (ndc.x * 0.5 + 0.5) * size[0] as f32,
++                (0.5 - ndc.y * 0.5) * size[1] as f32,
++            );
++            lo = lo.min(px);
++            hi = hi.max(px);
++        }
++    }
++    match front {
++        0 => Cover::Nothing,
++        8 => Cover::Rect([lo.x - 2.0, lo.y - 2.0, hi.x + 2.0, hi.y + 2.0]),
++        _ => Cover::Everywhere,
++    }
++}
++
++/// Fills `words` with each 16x16 tile's two lists of the lights that can reach it: header
++/// (surface start, surface length, halo start, halo length) per tile, then the indices; a
++/// length of `EVERY_LIGHT` stands for all of `lights` (a list past the buffer's room). The
++/// surface list holds the lights whose sphere can touch what the tile sees. The halo list
++/// holds the lights whose halo can reach a ray of the tile: the shader adds a halo for the
++/// view *line* passing within half the radius of the light, so a ray pointing away from a light
++/// behind it is lit too, and the mirrored sphere is covered as well. Lights stay in order, so
++/// the sums are the ones of the full loop.
++fn tile_lists(
++    view_proj: &Mat4,
++    lights: &[HdLight],
++    size: [u32; 2],
++    scratch: &mut Vec<Vec<u16>>,
++    words: &mut Vec<u32>,
++) {
++    let tx = size[0].div_ceil(TILE).max(1) as usize;
++    let ty = size[1].div_ceil(TILE).max(1) as usize;
++    let tiles = tx * ty;
++    scratch.resize_with(tiles * 2, Vec::new);
++    scratch.truncate(tiles * 2);
++    scratch.iter_mut().for_each(Vec::clear);
++    let mut add = |list: usize, area: Cover, light: u16| match area {
++        Cover::Nothing => {}
++        Cover::Everywhere => {
++            for t in 0..tiles {
++                scratch[t * 2 + list].push(light);
++            }
++        }
++        Cover::Rect([x0, y0, x1, y1]) => {
++            let tile = TILE as f32;
++            if x1 < 0.0 || y1 < 0.0 || x0 >= size[0] as f32 || y0 >= size[1] as f32 {
++                return;
++            }
++            let from = |v: f32, n: usize| ((v / tile).floor().max(0.0) as usize).min(n - 1);
++            for y in from(y0, ty)..=from(y1, ty) {
++                for x in from(x0, tx)..=from(x1, tx) {
++                    scratch[(y * tx + x) * 2 + list].push(light);
++                }
++            }
++        }
++    };
++    for (i, l) in lights.iter().enumerate() {
++        let c = glam::Vec3::new(l.pos[0], l.pos[1], l.pos[2]);
++        add(0, cover(view_proj, c, l.pos[3], size), i as u16);
++        // The shader's halo reach: the line within `radius / 2 - 0.5` of the light.
++        let reach = l.pos[3] * 0.5 - 0.5;
++        if reach > 0.0 || !reach.is_finite() {
++            add(1, cover(view_proj, c, reach, size), i as u16);
++            add(1, cover(view_proj, -c, reach, size), i as u16);
++        }
++    }
++    words.clear();
++    words.resize(tiles * 4, 0);
++    let mut room = TILE_INDICES;
++    for t in 0..tiles {
++        for list in 0..2 {
++            let ids = &mut scratch[t * 2 + list];
++            // Both the sphere and its mirror can name a light: once is enough.
++            ids.dedup();
++            let at = t * 4 + list * 2;
++            if ids.len() > room {
++                words[at + 1] = EVERY_LIGHT;
++            } else {
++                room -= ids.len();
++                words[at] = words.len() as u32;
++                words[at + 1] = ids.len() as u32;
++                words.extend(ids.iter().map(|&i| u32::from(i)));
++            }
++        }
++    }
++}
++
+ fn module(device: &wgpu::Device, label: &str, body: &str) -> wgpu::ShaderModule {
+     device.create_shader_module(wgpu::ShaderModuleDescriptor {
+         label: Some(label),
+@@ -527,6 +680,11 @@ impl Hd {
+                 wgpu::BindingType::Sampler(wgpu::SamplerBindingType::Comparison),
+                 FLOAT,
+                 SAMPLER,
++                wgpu::BindingType::Buffer {
++                    ty: wgpu::BufferBindingType::Storage { read_only: true },
++                    has_dynamic_offset: false,
++                    min_binding_size: None,
++                },
+             ]),
+         });
+         let bloom_layout = device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
+@@ -687,6 +845,10 @@ impl Hd {
+             up_groups: Vec::new(),
+             frame,
+             lights,
++            tiles: tiles_buffer(device, [1, 1]),
++            tiles_x: 1,
++            tile_scratch: Vec::new(),
++            tile_words: Vec::new(),
+             sampler,
+             light_layout,
+             light_pipeline,
+@@ -713,6 +875,8 @@ impl Hd {
+         self.depth = target(device, "HD depth", size, wgpu::TextureFormat::Depth32Float).view;
+         self.lit = target(device, "HD lit", size, HDR).view;
+         self.fx = target(device, "HD post", size, HDR).view;
++        self.tiles = tiles_buffer(device, size);
++        self.tiles_x = size[0].div_ceil(TILE).max(1);
+         self.bloom = (0..BLOOM_LEVELS)
+             .map(|k| {
+                 let s = [(size[0] >> (k + 1)).max(1), (size[1] >> (k + 1)).max(1)];
+@@ -743,6 +907,15 @@ impl Hd {
+         if n > 0 {
+             queue.write_buffer(&self.lights, 0, bytemuck::cast_slice(&lights[..n]));
+         }
++        // Written every frame, empty too: the shader reads the counts, not `params.x`.
++        tile_lists(
++            &scene.view_proj,
++            &lights[..n],
++            self.size,
++            &mut self.tile_scratch,
++            &mut self.tile_words,
++        );
++        queue.write_buffer(&self.tiles, 0, bytemuck::cast_slice(&self.tile_words));
+         self.frames = self.frames.wrapping_add(1);
+         // The sun by day, the moon (opposite) by night, faded out round the horizon.
+         let (dir, strength, color) = light_of(scene);
+@@ -773,7 +946,7 @@ impl Hd {
+                 if strength > 0.0 { 1.0 } else { 0.0 },
+                 CASCADES[0],
+                 CASCADES[1],
+-                0.0,
++                self.tiles_x as f32,
+             ],
+         };
+         queue.write_buffer(&self.frame, 0, bytemuck::bytes_of(&frame));
+@@ -933,6 +1106,10 @@ impl Hd {
+                         binding: 11,
+                         resource: wgpu::BindingResource::Sampler(lightmap.1),
+                     },
++                    wgpu::BindGroupEntry {
++                        binding: 12,
++                        resource: self.tiles.as_entire_binding(),
++                    },
+                 ],
+             });
+             self.light_group = Some((key, group));
+@@ -1102,3 +1279,56 @@ pub fn cascades(camera: glam::DVec3, light: glam::Vec3) -> [Mat4; 2] {
+         (projection * view).as_mat4()
+     })
+ }
++
++#[cfg(test)]
++mod tests {
++    use super::*;
++
++    #[test]
++    fn lighting_shader_parses() {
++        for (name, body) in [("light", LIGHT), ("bloom", BLOOM)] {
++            let source = format!("{COMMON}{body}");
++            let module = naga::front::wgsl::parse_str(&source).unwrap_or_else(|e| {
++                panic!("{name}: {}", e.emit_to_string(&source));
++            });
++            naga::valid::Validator::new(
++                naga::valid::ValidationFlags::all(),
++                naga::valid::Capabilities::all(),
++            )
++            .validate(&module)
++            .unwrap_or_else(|e| panic!("{name}: {e:?}"));
++        }
++    }
++
++    #[test]
++    fn tile_lists_keep_lights_that_reach_a_tile() {
++        let size = [320, 160];
++        let proj = Mat4::perspective_rh(1.0, 2.0, 0.05, 1000.0);
++        let light = |x: f32, y: f32, z: f32, r: f32| HdLight {
++            pos: [x, y, z, r],
++            color: [1.0; 4],
++        };
++        let lights = [
++            // Dead ahead and small; far to the side; behind the camera; holding the camera.
++            light(0.0, 0.0, -20.0, 4.0),
++            light(30.0, 0.0, -5.0, 4.0),
++            light(0.0, 0.0, 10.0, 8.0),
++            light(1.0, 0.0, 0.0, 6.0),
++        ];
++        let (mut scratch, mut words) = (Vec::new(), Vec::new());
++        tile_lists(&proj, &lights, size, &mut scratch, &mut words);
++        let list = |tile: usize, which: usize| -> Vec<u32> {
++            let (start, len) = (words[tile * 4 + which * 2], words[tile * 4 + which * 2 + 1]);
++            words[start as usize..(start + len) as usize].to_vec()
++        };
++        // The centre tile sees the first light and the one at the camera, in both lists.
++        let centre = 5 * 20 + 10;
++        assert_eq!(list(centre, 0), vec![0, 3]);
++        assert!(list(centre, 1).contains(&0) && list(centre, 1).contains(&3));
++        // A far corner sees only the one at the camera.
++        assert_eq!(list(0, 0), vec![3]);
++        // The light behind the camera shows in the halo list where the view points away.
++        assert!(list(centre, 1).contains(&2));
++        assert!(!list(0, 0).contains(&2));
++    }
++}
+-- 
+2.54.0 (Apple Git-157)
+