From ffa538c39dc3aa9f60583dacff3adb9a59a42908 Mon Sep 17 00:00:00 2001
From: Convey123 <Convey123@users.noreply.github.com>
Date: Thu, 8 Oct 2026 18:48:53 +0800
Subject: [PATCH 1/7] =?UTF-8?q?feedback7=20R22-RENDER:=20=E8=B5=A4?=
 =?UTF-8?q?=E5=88=83=E6=98=8E=E9=9C=84=E9=99=88=20S3's=20sword=20wave=20is?=
 =?UTF-8?q?=20drawn=20along=20its=20path=20=E2=80=94=20the=20sim=20sends?=
 =?UTF-8?q?=20its=20position=20as=20a=20chen3Wave=20fx=20every=200.12=20s,?=
 =?UTF-8?q?=20the=20client=20draws=20a=20'qi'=20blade=20(PR=20#382=20by=20?=
 =?UTF-8?q?@Convey123,=20owner=20item=2012);=20golden:=20diy-073=20/=20diy?=
 =?UTF-8?q?-074=20events.fx=20and=20fx.chen3Wave=20only?=
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Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The 赤霄·天喟 wave is a kit-managed probe (it turns corners and lives as long as the skill), not a snapshot
projectile, and the sim emitted one `dash` at the cast and a `slash` per hit — nothing along the way, so the client
drew no wave. op-chen3.js now emits fx('chen3Wave', { x, y, fromX, fromY, dr, dc, id }) every WAVE_FX_EVERY (0.12 s;
4 ticks), the trail restarting at a corner; render/fx registers chen3Wave → 'qi' (pt: drawn at the event, never on
her) and draws a streak plus a crescent head turned the way it travels. The look is a procedural stand-in, not the
official particle prefab.

Substantially @Convey123's code (PR #382), authored as theirs. Changed on review: the head is projected after
streak() — streak() reuses the effect system's projection scratch, so the PR drew the crescent on the trail's start,
one event behind the wave — and the trail, head and heading share one height; an unused test variable dropped.

Golden: diy-073 (5_diy*=chen3 S3 in two slots) events.fx 508 → 1558, fx.chen3Wave → 1050; diy-074 (6_diy*=chen3 S3)
events.fx 272 → 872, fx.chen3Wave → 600. HP, kills, damage, hooks and snapshot hashes unchanged: battle.fx only
records an event.

Tests: test/content/op_chen3.test.js (+1: the events, their cadence, id, direction, trail start, silence after the
skill) 12/12; test/render/fxchen3wave.test.js (new, 6: the archetype, drawn at the wave not at her, the head on the
wave and turned with it, a sweep joining into one trail, junk input, nothing left after) 6/6; boardart 15/15.
---
 public/js/render/fx/kinds.js            |   3 +
 public/js/render/fx/simfx.js            |  26 ++++-
 server/sim/content/kits/ops/op-chen3.js |  25 ++++-
 test/content/op_chen3.test.js           |  33 ++++++
 test/golden/diy.json                    |   8 +-
 test/render/fxchen3wave.test.js         | 132 ++++++++++++++++++++++++
 6 files changed, 219 insertions(+), 8 deletions(-)
 create mode 100644 test/render/fxchen3wave.test.js

diff --git a/public/js/render/fx/kinds.js b/public/js/render/fx/kinds.js
index b9d0199c..b721a01a 100644
--- a/public/js/render/fx/kinds.js
+++ b/public/js/render/fx/kinds.js
@@ -15,6 +15,9 @@ export const FX_KINDS = Object.freeze({
   frostNova: { a: 'blast', c: 0x9fe6ff, smoke: 0x1c2630 }, sunBurst: { a: 'blast', c: 0xffe28a }, meltdown: { a: 'blast', c: 0xff5a2a, r: 1.5, heavy: true },
   iceSpike: { a: 'blast', c: 0xbfeeff, smoke: 0x1c2630 }, rockfall: { a: 'blast', c: 0xc8a878, smoke: 0x4a3f33 }, rockslide: { a: 'blast', c: 0xc8a878, smoke: 0x4a3f33 },
   finale: { a: 'blast', c: 0xffd45a, r: 1.5 }, swordStorm: { a: 'blast', c: 0xdfe8ff }, swordRain: { a: 'blast', c: 0xdfe8ff }, liberate: { a: 'blast', c: 0xffffff },
+  // 赤刃明霄陈 S3 赤霄·天喟 的龙剑气: a travelling blade, drawn from the sim's per-interval `chen3Wave` events (its own
+  // position + the previous point + direction); `pt` because it is not at the caster (it roams and passes by her tile)
+  chen3Wave: { a: 'qi', c: 0xdfe8ff, pt: true },
   quadShot: { a: 'volley', c: 0xfff2d0 }, featherArrow: { a: 'counter', c: 0xfff2d0 },
   burst: { a: 'element', c: 0xd0a0ff },
   // areas
diff --git a/public/js/render/fx/simfx.js b/public/js/render/fx/simfx.js
index 4adf4327..0796e434 100644
--- a/public/js/render/fx/simfx.js
+++ b/public/js/render/fx/simfx.js
@@ -47,10 +47,11 @@ export class FxSim {
   /**
    * b.ev 'fx': every kind the sim / content emits has a visual (FX_KINDS archetypes: blast, shell, zone, telegraph,
    * heal, sp, shield, shatter, summon, vanish, blink, move, wave, mark, reticle, buff, lift, sleep, crit, dodge,
-   * counter, dp, coin, crate, down, beam, bolt, strike, volley, pillar, lp, chill, element, flame), except kinds whose
+   * counter, dp, coin, crate, down, beam, bolt, strike, volley, pillar, lp, chill, element, flame, qi), except kinds whose
    * archetype is 'none' (hitCap: a leader hit cancelled by 限伤 draws nothing); unknown kinds get a generic sparkle. `extra` keys used: id (anchor unit — or the shooter of a `pt` kind), r | radius, dur | duration,
    * t (shell flight, game s), src / from / to / target / targets (unit ids), fx, fy / fromX, fromY / tx, ty (positions),
-   * element, n, scale, kind, tiles, hold ('lock': the reticle waits while the shooter's skill runs).
+   * element, n, scale, kind, tiles, hold ('lock': the reticle waits while the shooter's skill runs), dr / dc (a
+   * direction in tiles: 'qi' points its blade that way).
    */
   simFx(kind, x, y, extra) {
     const ex = extra && typeof extra === 'object' ? extra : {};
@@ -168,6 +169,27 @@ export class FxSim {
         }
         break;
       }
+      // a travelling blade (赤刃明霄陈 S3's 龙剑气): a short trail from where it was to where it is, plus a crescent head
+      // turned the way it moves — the sim sends one of these every 0.12 s, and the trail outlives that gap so the
+      // events join into one sweeping wave. A procedural stand-in (the official effect is a particle prefab this client
+      // does not extract). Trail, head and heading share one height; the head is projected after streak(), which
+      // reuses this._p / this._q (projected before it, the head was drawn at the trail's start, one event behind)
+      case 'qi': {
+        const z = at.z + 0.35;
+        const fx0 = num(ex.fromX, NaN), fy0 = num(ex.fromY, NaN);
+        if (Number.isFinite(fx0) && Number.isFinite(fy0)) this.streak(fx0, fy0, at.x, at.y, z, col, 0.34);
+        const h = cam.project(at.x, at.y, z, this._p), hx = h.x, hy = h.y, hs = h.s;
+        const dr = num(ex.dr, NaN), dc = num(ex.dc, NaN);
+        let rot = 0;
+        if (Number.isFinite(dr) && Number.isFinite(dc) && (dr || dc)) {
+          const q = cam.project(at.x + dc * 0.5, at.y + dr * 0.5, z, this._q);
+          // the `slash` sprite's crescent bulges along its local −y, so this turns that edge onto the travel direction
+          rot = Math.atan2(q.x - hx, -(q.y - hy));
+        }
+        this.particle('slash', hx, hy, { tint: col, life: 0.3, s0: hs / 128 * 1.3, s1: hs / 128 * 2.0, a0: 0.9, a1: 0, rot });
+        this.particle('glow', hx, hy, { tint: col, life: 0.26, s0: hs / 128 * 0.8, s1: hs / 128 * 1.5, a0: 0.55, a1: 0 });
+        break;
+      }
       case 'wave': {
         const k = clamp(num(ex.scale, 1), 0.5, 4);
         const rr = Math.max(0.8, r * (ex.scale ? Math.min(2, k / 2) : 1));
diff --git a/server/sim/content/kits/ops/op-chen3.js b/server/sim/content/kits/ops/op-chen3.js
index 772446e9..aaa86c20 100644
--- a/server/sim/content/kits/ops/op-chen3.js
+++ b/server/sim/content/kits/ops/op-chen3.js
@@ -46,7 +46,10 @@
 //   field, the stage tiles beyond it are another player's half] —, an 侵入点 or a 保护目标 it turns 90° clockwise (four
 //   turns at most per tick; boxed in on every side it waits) and forgets whom it hit; each enemy it can select within 1.3
 //   (air too) is hit once per straight run for the larger of hp_ratio × its current HP (the unit's own HP, PRTS) and
-//   projectile_min_atk_scale × her ATK at the hit, arts (RES applies — PRTS "非伤害保底或无视法术抗性"; 普通伤害). Her
+//   projectile_min_atk_scale × her ATK at the hit, arts (RES applies — PRTS "非伤害保底或无视法术抗性"; 普通伤害).
+//   The wave is a kit-managed probe, not a snapshot projectile, so it is shown with `fx('chen3Wave')` events every
+//   WAVE_FX_EVERY s (its position, the previous point and its direction — render/fx 'qi': a procedural blade trail with
+//   a crescent head, not the official particle prefab); before that the 龙剑气 had no visual at all (PR #382). Her
 //   begin clips (S1 0.2 s, S3 0.433 s) are not modelled [ASSUMED: the engine starts skills at once].
 
 import { num, talentBb, traitBb, skillRec, statBuff, toggleBuff, up } from '../shared/tier1.js';
@@ -69,6 +72,14 @@ const RETARGET_RADIUS = 1.7;
 const WAVE_SPEED = 1.5;
 const WAVE_PROBE = 0.25;
 const WAVE_HIT_RADIUS = 1.3;
+/**
+ * How often the wave's position is sent to the client as an `fx` (`chen3Wave`, carrying the previous point and its
+ * direction). The wave is a kit-managed probe (it turns corners and lives as long as the skill), so it is not in the
+ * snapshot's projectile list: without these events the client has nothing to draw and the 龙剑气 is invisible (the cast
+ * emitted one `dash` puff and each hit a `slash` spark). The rate is the renderer's: each event draws a short blade
+ * trail whose life outlasts the gap, so the events join into one continuous wave.
+ */
+const WAVE_FX_EVERY = 0.12;
 /** S1's early end: a silence of hers that ends within this of the skill's planned end ended with it. */
 const SILENCE_SLACK = 0.1;
 const AIR = Object.freeze({ canHitFly: true });
@@ -215,7 +226,8 @@ export default {
           attack: { atkScale: num(b3['attack@atk_scale'], 1), hits: 3 },   // `_additionalTimes` 2
           onStart({ battle, unit, skill }) {
             const [dr, dc] = unit.fwd;
-            unit.mem.chen3Wave = { x: unit.x, y: unit.y, dr, dc, hit: new Set(), act: skill.activations, seq: unit.deploySeq };
+            unit.mem.chen3Wave = { x: unit.x, y: unit.y, dr, dc, hit: new Set(), act: skill.activations, seq: unit.deploySeq,
+              fx: 0, fxX: unit.x, fxY: unit.y };
             battle.fx('dash', { x: unit.x, y: unit.y, id: unit.id, skill: 'chen3:wave' });
           },
           onEnd({ unit }) { unit.mem.chen3Wave = null; },
@@ -285,8 +297,17 @@ export default {
             w.dr = 0 - w.dc;    // (`0 - x`: never a negative zero)
             w.dc = dr;
             w.hit.clear();
+            w.fxX = w.x; w.fxY = w.y;   // the drawn trail starts again at the corner (no streak across the turn)
           }
           if (!waveBlocked(battle, w)) { w.x += w.dc * WAVE_SPEED * dt; w.y += w.dr * WAVE_SPEED * dt; }
+          // the 龙剑气 itself: tell the client where it is now (and where it came from) so it can be drawn — while it
+          // runs, while it is boxed in waiting, and after a turn (the direction comes along for the renderer)
+          w.fx += dt;
+          if (w.fx >= WAVE_FX_EVERY) {
+            w.fx = 0;
+            battle.fx('chen3Wave', { x: w.x, y: w.y, fromX: w.fxX, fromY: w.fxY, dr: w.dr, dc: w.dc, id: unit.id, skill: 'chen3:wave' });
+            w.fxX = w.x; w.fxY = w.y;
+          }
           for (const e of battle.foesInRadius(w.x, w.y, WAVE_HIT_RADIUS)) {
             if (w.hit.has(e) || !canTargetEnemy(unit, e, AIR)) continue;
             w.hit.add(e);
diff --git a/test/content/op_chen3.test.js b/test/content/op_chen3.test.js
index d917c164..aa9686e9 100644
--- a/test/content/op_chen3.test.js
+++ b/test/content/op_chen3.test.js
@@ -319,6 +319,39 @@ test('S3 赤霄·天喟 (MANUAL, data ACTIVE_RANGE on 3-12): range 3-12, each at
   }
 });
 
+// 用户报告: 「自选干员赤刃明霄陈三技能的龙剑气看不到」. 波是 kit 自己管的探针（会拐弯、跟技能同寿），不在快照的 projectile
+// 列表里，所以客户端只能靠 fx 事件画它——原来只在起手发了一个 `dash`、每次命中发 `slash`，波本身**没有任何事件**。
+// 现在每 WAVE_FX_EVERY(0.12) 秒发一次 `chen3Wave`：位置 + 上一个点（拖尾）+ 方向（月牙朝向）。
+test('S3: the 龙剑气 streams its position to the client as `chen3Wave` fx (position, previous point, direction)', () => {
+  const { h, u } = field({ tier: 6, elite: true, skill: 2 });
+  u.skill.gainSp(999);
+  h.spawn('enemy_dummy', { pos: [10, 6] });          // a target in range: the MANUAL skill casts
+  const waveFx = () => h.events.filter((e) => e[0] === 'fx' && e[1] === 'chen3Wave');
+  assert.ok(h.runUntil(() => u.skill.active, 2));
+  h.run(1);
+  const fx = waveFx();
+  assert.ok(fx.length >= 6, `每 0.12 秒一次 ⇒ 1 秒约 8 次（实际 ${fx.length}）`);
+  for (const [, , x, y, ex] of fx) {
+    assert.equal(ex.id, u.id, '带着她的 id（可定位到玩家/队伍）');
+    assert.equal(ex.skill, 'chen3:wave');
+    assert.ok(Math.abs(x - u.tileC) <= 12 && Math.abs(y - u.tileR) <= 12, '波在场上');
+  }
+  // 位置随时间前移、方向与朝向一致（row 10 向右），from 是上一个点（拖尾）
+  const [, , x0, , ex0] = fx[0];
+  const last = fx[fx.length - 1];
+  assert.ok(last[2] > x0, `向前推进（${x0.toFixed(2)} → ${last[2].toFixed(2)}）`);
+  assert.deepEqual([last[4].dc, last[4].dr], [1, 0], '方向 = 她的朝向（向右）');
+  assert.ok(Math.abs(ex0.fromX - u.tileC) < 0.5 && Math.abs(ex0.fromY - u.tileR) < 0.5, '第一个事件从上场点开始');
+  assert.ok(last[4].fromX < last[2], 'from 是上一个事件的点（拖尾向前）');
+  // 技能结束后不再发
+  h.runUntil(() => !u.skill.active, 25);
+  h.step();
+  const n = waveFx().length;
+  h.run(2);
+  assert.equal(waveFx().length, n, '技能结束后不再有波的 fx');
+  done(h);
+});
+
 test('S3: the sword wave leaves her tile forward at 1.5 tiles/s, hits each enemy within 1.3 once per straight run (air too) for max(6 % of its HP, 530 % / 550 % ATK) arts, turns clockwise at the field\'s edge / high ground / gates and forgets whom it hit, and is gone with the skill', () => {
   for (const [tier, elite] of [[5, false], [6, true]]) {
     const sk = skillOf(tier, elite, S3);
diff --git a/test/golden/diy.json b/test/golden/diy.json
index c467dac7..42e8f659 100644
--- a/test/golden/diy.json
+++ b/test/golden/diy.json
@@ -3158,8 +3158,8 @@
         "enemy_9010_acpupp": [39,6,33,47997,613287]
       },
       "hooks": [1,188,6098,435,435,1218,1333,444,85,174,21,21,0,18383,8,44,156,89,1,91,0,0,4],
-      "events": {"atk":476,"deploy":30,"die":85,"dmg":1333,"engage":11,"fx":508,"heal":7,"leak":89,"skill":42,"spawn":170,"status":9},
-      "fx": {"blink":7,"dash":14,"dodge":4,"ember":6,"shield":138,"slash":308,"summon":21,"telegraph":6,"thorns":4},
+      "events": {"atk":476,"deploy":30,"die":85,"dmg":1333,"engage":11,"fx":1558,"heal":7,"leak":89,"skill":42,"spawn":170,"status":9},
+      "fx": {"blink":7,"chen3Wave":1050,"dash":14,"dodge":4,"ember":6,"shield":138,"slash":308,"summon":21,"telegraph":6,"thorns":4},
       "snaps": "f1faec58 cbf72c28 58e3f561 b8182f46 b1f5b0f5 1de38a22 bc7c2a2b f233c949 01d56108 560ee3fc 8ec7a4b9 b95b08ce 1943beb7 c593b60a e179c3a0 4a2ad117 171d3fbd 1e1c4411 efd84577 32339940 33fdecb2"
     },
     "diy-074": {
@@ -3197,8 +3197,8 @@
       ],
       "enemies": {"enemy_1229_darmy":[27,7,20,398,133429],"enemy_1229_darmy_2":[57,14,43,11905,308752],"enemy_1275_dwlock_2":[21,6,15,50953,369503]},
       "hooks": [1,133,6831,258,258,706,729,74,50,128,11,11,0,8921,19,29,105,78,1,50,0,2,24],
-      "events": {"atk":301,"deploy":28,"die":50,"dmg":729,"engage":12,"fx":272,"heal":1,"leak":78,"skill":22,"spawn":117,"status":9},
-      "fx": {"beam":46,"blink":4,"burst":2,"dash":8,"dodge":24,"shield":74,"slash":114},
+      "events": {"atk":301,"deploy":28,"die":50,"dmg":729,"engage":12,"fx":872,"heal":1,"leak":78,"skill":22,"spawn":117,"status":9},
+      "fx": {"beam":46,"blink":4,"burst":2,"chen3Wave":600,"dash":8,"dodge":24,"shield":74,"slash":114},
       "snaps": "498914af 0a79facb 2cda1fb6 0a030d4c 9ce66676 179c11c1 62b416c3 fe75747c 619a4d17 62a8fa9d 86e914bd b1b84020 f6408a48 d11bff81 68c04d21 052d976c 5b0d0f6d 7b80bb08 e10c9b3e 0befc79d 41d43704 1e0376b1 8d64e6cf"
     },
     "diy-075": {
diff --git a/test/render/fxchen3wave.test.js b/test/render/fxchen3wave.test.js
new file mode 100644
index 00000000..fd4faaef
--- /dev/null
+++ b/test/render/fxchen3wave.test.js
@@ -0,0 +1,132 @@
+// test/render/fxchen3wave.test.js — 赤刃明霄陈 S3 赤霄·天喟 的「龙剑气」(用户报告: 三技能的龙剑气看不到).
+//
+// The wave is a kit-managed probe in the sim (server/sim/content/kits/ops/op-chen3.js): it leaves her tile forward at
+// 1.5 tiles/s, turns 90° at the field's edge / high ground / gates, and lives as long as the skill. It is not in the
+// snapshot's projectile list, so the client can only draw it from `fx` events — and before this change the sim sent
+// none for the wave itself (one `dash` puff at the cast, one `slash` spark per enemy hit): the 龙剑气 was invisible.
+// The sim now emits `fx('chen3Wave', { x, y, fromX, fromY, dr, dc, id, skill })` every 0.12 s — its position, the
+// previous point (the trail) and its direction (the crescent's heading) — and render/fx.js draws the 'qi' archetype.
+// Against the headless fake PIXI (test/render/fakepixi.js), like fxflame.test.js.
+
+import { test, describe, before, after } from 'node:test';
+import assert from 'node:assert/strict';
+import { installFakePixi, fakeViewCtx } from './fakepixi.js';
+import { presetCamera } from '../../public/js/render/projection.js';
+
+let fake, FX;
+before(async () => {
+  fake = installFakePixi();
+  FX = await import('../../public/js/render/fx.js');
+});
+after(() => fake.restore());
+
+const DT = 1 / 120;
+const cam = presetCamera('normal', { width: 1600, height: 900 });
+const unit = (id, x, y, o = {}) => ({ id, x, y, z: 0, hover: 0, _headTiles: 1.2, alive: true, destroyed: false, info: { defId: 'x' }, onHit() {}, ...o });
+
+function makeFx(views, ts = 1) {
+  const P = fake.P;
+  const ctx = fakeViewCtx(P);
+  const map = new Map(views.map((v) => [v.id, v]));
+  const fx = new FX.FxSystem({
+    P, layers: ctx.layers, cam: () => cam, heightAt: () => 0, settings: { quality: 'high', damageNumbers: true },
+    timeScale: () => ts, loadLevel: () => 0, subProfOf: () => null, view: (id) => map.get(id) || null,
+    screenSize: () => ({ width: 1600, height: 900 }), fieldTop: () => 120,
+  });
+  return { fx, map };
+}
+const run = (fx, seconds) => { for (let t = 0; t < seconds - 1e-9; t += DT) fx.update(DT); };
+/** One sim event of the wave: its position, the previous point and the direction (`dc` cols, `dr` rows). */
+const wave = (fx, id, x, y, fromX, fromY, dc = 1, dr = 0) => fx.simFx('chen3Wave', x, y, { x, y, fromX, fromY, dr, dc, id, skill: 'chen3:wave' });
+/** Screen box of the drawn trail/head: min/max of every live particle position. */
+const drawn = (fx) => {
+  const list = fx.parts.filter((p) => p.sp && p.sp.visible !== false);
+  if (!list.length) return null;
+  const xs = list.map((p) => p.sp.position.x), ys = list.map((p) => p.sp.position.y);
+  return { n: list.length, x0: Math.min(...xs), x1: Math.max(...xs), y0: Math.min(...ys), y1: Math.max(...ys) };
+};
+
+describe('赤刃明霄陈 S3 龙剑气: 波自己会被画出来 (issue: 看不到)', () => {
+  test('its own archetype — a travelling blade, not the generic sparkle or a dust puff', () => {
+    assert.equal(FX.FX_KINDS.chen3Wave.a, 'qi');
+    assert.equal(FX.fxSpec('chen3Wave').a, 'qi');
+    assert.equal(FX.fxSpec('chen3Wave').pt, true, 'drawn at the wave (never anchored to the caster)');
+  });
+
+  test('one event draws a trail and a crescent head at the wave, not at her', () => {
+    const her = unit(1, 3, 10), waveAt = { x: 8, y: 10 };
+    const { fx } = makeFx([her]);
+    assert.equal(drawn(fx), null, 'nothing before the event');
+    wave(fx, her.id, waveAt.x, waveAt.y, 7.8, 10);
+    run(fx, 1 / 60);
+    const box = drawn(fx);
+    assert.ok(box && box.n >= 2, `the trail and the head are drawn (${box && box.n} pieces)`);
+    const at = cam.project(waveAt.x, waveAt.y, 0.35, { x: 0, y: 0, s: 0, depth: 0 });
+    const hers = cam.project(her.x, her.y, 0.5, { x: 0, y: 0, s: 0, depth: 0 });
+    const near = (v, t) => Math.abs(v - t) <= 90;
+    assert.ok(near(box.x1, at.x) || near(box.x0, at.x), `drawn around the wave (${Math.round(box.x0)}…${Math.round(box.x1)} vs ${Math.round(at.x)})`);
+    assert.ok(Math.abs(box.x1 - hers.x) > 60, 'not at her tile');
+  });
+
+  // streak() reuses the effect system's projection scratch: a head placed from it sat on the trail's start, one event
+  // (~0.2 tile) behind the wave
+  test('the crescent head sits on the wave itself (not on the trail\'s start) and points the way it travels', () => {
+    const her = unit(1, 3, 10);
+    const { fx } = makeFx([her]);
+    const heads = () => fx.parts.filter((p) => p.sp.visible !== false && p.sp.texture === fx.tex.slash);
+    wave(fx, her.id, 8, 10, 7.6, 10, 1, 0);                    // moving right (+col)
+    const right = heads();
+    assert.equal(right.length, 1, 'one crescent head');
+    const at = cam.project(8, 10, 0.35, { x: 0, y: 0, s: 0, depth: 0 });
+    assert.ok(Math.abs(right[0].x - at.x) < 0.5 && Math.abs(right[0].y - at.y) < 0.5,
+      `head at the wave (${right[0].x.toFixed(1)}, ${right[0].y.toFixed(1)}) vs (${at.x.toFixed(1)}, ${at.y.toFixed(1)})`);
+    assert.ok(Math.abs(right[0].sp.rotation - Math.PI / 2) < 0.35, `bulge to the right (rot ${right[0].sp.rotation.toFixed(2)})`);
+    run(fx, 1);
+    wave(fx, her.id, 8, 10, 8, 9.6, 0, 1);                     // moving up the screen (+row: the far side)
+    const up = heads();
+    assert.equal(up.length, 1);
+    assert.ok(Math.abs(up[0].sp.rotation) < 0.35, `bulge up (rot ${up[0].sp.rotation.toFixed(2)})`);
+  });
+
+  test('the events of a sweep join into one trail that goes the way it travels', () => {
+    const her = unit(1, 3, 10);
+    const { fx } = makeFx([her]);
+    let prev = 3;
+    const fronts = [];
+    for (let i = 0; i < 8; i++) {           // 0.12 s apart at 1.5 tiles/s ⇒ 0.18 tile a step
+      const x = 3 + 0.18 * (i + 1);
+      wave(fx, her.id, x, 10, prev, 10);
+      prev = x;
+      run(fx, 0.12);
+      fronts.push(drawn(fx).x1);
+    }
+    const box = drawn(fx);
+    assert.ok(box && box.n >= 4, `the recent steps are still alive (${box && box.n} pieces)`);
+    // the drawn front walks forward with the wave (each event is drawn ahead of the last, the older ones still fading)
+    for (let i = 1; i < fronts.length; i++) {
+      assert.ok(fronts[i] > fronts[i - 1] - 1, `step ${i}: the front moved on (${Math.round(fronts[i - 1])} → ${Math.round(fronts[i])})`);
+    }
+    assert.ok(fronts[fronts.length - 1] - fronts[0] > 60, `the sweep crossed the field (${Math.round(fronts[0])} → ${Math.round(fronts[fronts.length - 1])} px)`);
+  });
+
+  test('a wave boxed in (no movement) and a junk extra never throw', () => {
+    const her = unit(1, 3, 10);
+    const { fx } = makeFx([her]);
+    wave(fx, her.id, 8, 10, 8, 10, 0, 0);                    // standing still: no direction
+    wave(fx, her.id, 8, 10, undefined, undefined);
+    fx.simFx('chen3Wave', 8, 10, { id: her.id });            // bare event
+    fx.simFx('chen3Wave', NaN, NaN, { id: her.id, dr: 1, dc: 0 });
+    run(fx, 0.2);
+    assert.ok(fx.counts.particles > 0, 'still drawn');
+  });
+
+  test('the whole thing is gone once the events stop', () => {
+    const her = unit(1, 3, 10);
+    const { fx } = makeFx([her]);
+    wave(fx, her.id, 8, 10, 7.8, 10);
+    run(fx, 0.05);
+    assert.ok(drawn(fx).n > 0);
+    run(fx, 1);                                              // every trail/head particle expires (life 0.34 s max)
+    assert.equal(drawn(fx), null, 'nothing is left hanging on the field');
+  });
+});

From 8a64edc9e99b15b54a3d9bb0c9c6acd09f91986a Mon Sep 17 00:00:00 2001
From: ZiyueW1116 <ZiyueW1116@users.noreply.github.com>
Date: Thu, 8 Oct 2026 18:54:54 +0800
Subject: [PATCH 2/7] =?UTF-8?q?feedback7=20R22-RENDER:=20an=20enemy=20stan?=
 =?UTF-8?q?ding=20out=20its=20attack=20recovery=20is=20drawn=20standing=20?=
 =?UTF-8?q?=E2=80=94=20the=20snapshot=20carries=20stand=20/=20standCut=20a?=
 =?UTF-8?q?nd=20the=20interpolator=20holds=20the=20position=20until=20the?=
 =?UTF-8?q?=20recovery=20ends=20(PR=20#381=20by=20@ZiyueW1116,=20supersede?=
 =?UTF-8?q?s=20#307=20/=20#314);=20golden:=20unchanged?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Since 0.2.0 the sim stands an unblocked enemy for the rest of its attack clip (ai.js attackStand → atkStandUntil),
but render/interp.js lerped x/y over the whole snapshot gap, so the view slid through a recovery the sim held
(repro: a real 隐形弩手, snapshots 4.9 / 5.0, stand until 4.934 — sampled at 4.917 it slid at vx −0.2).

The snapshot now carries, only when non-empty, `stand: [[id, until]]` (atkStandUntil of enemies alive, deployed,
visible, neither feared nor stunned) and `standCut: [[id, at]]` (the latest time each listed enemy's recovery was cut
or ignored: a displacement, fear, a stun, hiding, leaving — Battle._cutAttackStand, display metadata the battle never
reads). sample() holds the older position until `until` and interpolates the rest (HP / SP keep the whole interval),
stays linear when the newer snapshot records a cut inside the interval, and extrapolates nothing for a newest snapshot
that shows a stand, a death, a stun or a block. Teleports and redeploys still snap first; old snapshots without the
fields interpolate as before.

Substantially @ZiyueW1116's code (PR #381), authored as theirs. Changed on review: the docs (SIM §9, design/network.md)
and code comments in English like the rest of them; the snapshot builds its listed-id set only when an enemy has a cut
to report.

Golden: unchanged — the digest canon hashes neither field and the sim's timing does not move (all 283 scenarios match).

Tests: test/render/attack-recovery-interp.test.js (new, 25: metadata validation, hold-then-slide, cuts, legacy
snapshots, extrapolation guards, real 隐形弩手 / Weedy push-kill / stun / freeze / sleep / levitate / block / fear
battles) 25/25; render/interp 16/16; sim battle, perf, robustness, downelem 69/69.
---
 docs/SIM.md                                |  15 +-
 docs/design/network.md                     |   9 +-
 public/js/render/interp.js                 |  71 +++-
 server/sim/ai.js                           |   2 +
 server/sim/battle/deploy.js                |   1 +
 server/sim/battle/displacement.js          |   1 +
 server/sim/battle/events.js                |  27 +-
 server/sim/battle/spawns.js                |   1 +
 test/render/attack-recovery-interp.test.js | 428 +++++++++++++++++++++
 types/core.js                              |   6 +-
 10 files changed, 541 insertions(+), 20 deletions(-)
 create mode 100644 test/render/attack-recovery-interp.test.js

diff --git a/docs/SIM.md b/docs/SIM.md
index 08a53a3f..80930f36 100644
--- a/docs/SIM.md
+++ b/docs/SIM.md
@@ -1296,7 +1296,7 @@ Unknown subprofessions fall back to the profession default (test `professions.te
 
 ## 9. Wire format (snapshot.js, DESIGN §8.2)
 
-- `snapshot()` → `{ fieldId, t, units: [[id, x, y, hp, maxHp, sp, spMax, flags, anim]], dp, killed, total, dps?, boss?, down?, elem? }`.
+- `snapshot()` → `{ fieldId, t, units: [[id, x, y, hp, maxHp, sp, spMax, flags, anim]], dp, killed, total, dps?, boss?, down?, elem?, stand?, standCut? }`.
   `sp/spMax` show remaining duration/ammo as a draining bar while a timed skill is active (ammo: `ammoLeft / ammoMax`, the
   activation's real total — 拉特兰's and 逃犯引渡手续's extra bullets included, community report #35). Units in DIE state stay 0.8 s.
   Active finite zero-SP duration skills display `timeLeft/duration` using `duration` as `spMax`; after end they show
@@ -1309,6 +1309,19 @@ Unknown subprofessions fall back to the profession default (test `professions.te
   knocked-out operator's tile, §1; `row, col` = the tile it lies on and comes back on, `unit.body`); `elem: [[id, element, fill,
   cooldownEnd, cooldown]]` (only when non-empty) = `elementView` of every unit with a gauge or a running 爆发冷却 (§3).
   `fieldMeta()` lists the knocked-out operators too (a client joining mid-battle shows them; DESIGN §18.3).
+  `stand: [[id, until]]` (only when non-empty) = the game time each enemy's attack recovery ends (`atkStandUntil`: it
+  stands for the rest of its attack clip, §1.2 `attackStand`) — enemies alive, deployed, visible, neither feared nor stunned;
+  display metadata the battle never reads (PR #381). When `until` falls between two snapshots the renderer holds the older
+  position until then and interpolates the rest of the interval (HP / SP keep the whole interval); a newer snapshot that
+  moved before `until` is interpolated linearly; while the newest snapshot still holds a stand nothing is extrapolated
+  (the next one confirms the move). A snapshot without the field interpolates over the whole interval, a teleport or a
+  redeploy still snaps first, and nothing is inferred from the attack animation. `standCut: [[id, at]]` (only when
+  non-empty) = the latest game time each enemy's recovery was cut or ignored (a displacement — 失衡 —, fear, a stun, hiding,
+  leaving the field), one per enemy: an interval whose newer snapshot carries a cut inside it is interpolated linearly even
+  when the older stand ended inside it too, and an older cut leaves a later stand alone. It covers the enemies listed in
+  `units` (the 0.8 s death window included), never a hidden or unlisted one. The newest snapshot showing a death, a stun
+  (freeze, sleep, 浮空 included) or a block is not extrapolated until a later snapshot shows it moving again; the
+  extrapolated velocity uses the same moving span as the interpolation (the stand is not in its denominator).
 - `drainEvents()` tuples: `['spawn', UnitInfo]` (first appearance), `['deploy', id]` (every (re)deploy and 【移动】 — the client plays the deploy and its interpolation snaps instead of sliding), `['atk', src, tgt, projKind]`
   (`none|arrow|bolt|bomb|lob|orb|drone|enemy|boomerang|droneBomb|chain|chainHeal`; a boomerang's way back has no event — the
   renderer flies it back to the thrower at `BOOMERANG_RETURN_SPEED`; an enemy's `profile.shot` may name another kind,
diff --git a/docs/design/network.md b/docs/design/network.md
index 384b3c9c..c1db75f0 100644
--- a/docs/design/network.md
+++ b/docs/design/network.md
@@ -23,7 +23,14 @@ S→C:
 - NOTE: game time in `b.snap`/`b.ev` is carried as **`gt`** (the frame's `t` is the message type).
 - Active finite zero-SP timed skills display `sp=timeLeft`, `spMax=duration` and `UF.SKILL`; after end they display
   `0/0`. Snapshot display capacity does not change runtime SP/cost.
-- `b.snap` — `{ fieldId, gt, units: [[id, x, y, hp, maxHp, sp, spMax, flags, anim]] , dp, killed, total, down?, elem? }` 20 Hz (a countdown summon's `hp` is maxHp × the share of its life left, §25.16.5). Optional, only when non-empty (§18.3): `down: [[id, respawnAt (game s), respawnTime (s), state, row, col]]` — knocked-out operators waiting to redeploy, `state` 0 counting | 1 timer done, waiting for DP | 2 timer done, its tile taken — a safeguard, no ally deploys there (sim/constants.js `DOWN_STATE`); `row, col` = the tile it lies on and comes back on (§21.24); `elem: [[id, element, fill, cooldownEnd (game s), cooldown (s)]]` — the one gauge a unit shows: the fullest (ties by the official element id 神经 < 侵蚀 < 灼燃 < 凋亡), fill with 2 decimals rounded DOWN and kept at 0.01–0.99 outside a burst (§20.8); during a 爆发冷却 the bursting element with fill 1 and the cooldown numbers (else 0, 0)
+- `b.snap` — `{ fieldId, gt, units: [[id, x, y, hp, maxHp, sp, spMax, flags, anim]] , dp, killed, total, down?, elem?, stand?, standCut? }` 20 Hz (a countdown summon's `hp` is maxHp × the share of its life left, §25.16.5). Optional, only when non-empty (§18.3): `down: [[id, respawnAt (game s), respawnTime (s), state, row, col]]` — knocked-out operators waiting to redeploy, `state` 0 counting | 1 timer done, waiting for DP | 2 timer done, its tile taken — a safeguard, no ally deploys there (sim/constants.js `DOWN_STATE`); `row, col` = the tile it lies on and comes back on (§21.24); `elem: [[id, element, fill, cooldownEnd (game s), cooldown (s)]]` — the one gauge a unit shows: the fullest (ties by the official element id 神经 < 侵蚀 < 灼燃 < 凋亡), fill with 2 decimals rounded DOWN and kept at 0.01–0.99 outside a burst (§20.8); during a 爆发冷却 the bursting element with fill 1 and the cooldown numbers (else 0, 0)
+  Optional, only when non-empty (PR #381; display metadata, SIM §9): `stand: [[id, until]]` — the game time an enemy's
+  attack recovery ends (`atkStandUntil`; enemies alive, deployed, visible, neither feared nor stunned): when it falls
+  between two snapshots the renderer holds the position until then and interpolates the rest (HP / SP unchanged), and
+  extrapolates nothing while the newest snapshot still holds a stand; `standCut: [[id, at]]` — the latest time each
+  listed enemy's recovery was cut or ignored (失衡, fear, stun, hiding, leaving): an interval with a cut inside it stays
+  linear. A newest snapshot showing a death, a stun or a block is not extrapolated. Old snapshots without them
+  interpolate linearly; nothing is inferred from the attack animation.
 - `b.ev` — `{ fieldId, ev: [ ... ] }` event tuples: `['spawn', UnitInfo]`, `['atk', srcId, tgtId, projKind]`, `['dmg', tgtId, amount, type]`, `['heal', tgtId, amount]`, `['skill', id, on:0|1]`, `['die', id, reason]` (reason `'killed'`, `'retreat'`, `'expired'` …; only `'killed'` plays an operator's knock-down sound), `['status', id, key, on]`, `['fx', kind, x, y, extra]` (`'hitCap' {id, n}` = a cancelled 限伤 hit, drawn as nothing, §20.12; `extra.form` = the unit's model form from then on (an enemy's mode, a 傀儡师's 替身 §22.11) — `shared/protocol.js fxForm`, state like a spawn: never dropped by the client, §21.4), `['layer', playerId, bondId, n]`, `['bounty', playerId, coins]`, `['deploy', id]`
 - `m.toast {kind, text}` · `m.ticker {text, id, type, priority, playerId}` (the strip plays the highest priority first, §21.10) · `m.emote {playerId, id}` · `m.result {...}`
 - `m.unitStats {seq, round, units: [unitStatsEntry]}` — the answer to `g.unitStats` (`seq` echoed): every own board operator / summon by uid with `{id, uid, defId, hp, alive, maxHp, atk, def, res, interval, blockCnt, moveSpeed, range?, base: {…same}}` (shared/protocol.js `unitStatsEntry`; `range` = an ally's live range grid, facing RIGHT, never a target-selection grid, §21.16) as its next battle starts (§18.5)
diff --git a/public/js/render/interp.js b/public/js/render/interp.js
index a3d99c8a..1df0d9de 100644
--- a/public/js/render/interp.js
+++ b/public/js/render/interp.js
@@ -8,7 +8,8 @@
 //     advancing at `rate` and gently steered back when network jitter pushes it off target (hard snap when it
 //     is more than `snapAfter` real seconds off),
 //   * extrapolation guard: renderT never runs more than `maxExtrapolate` real seconds past the newest snapshot;
-//     positions are extrapolated along the last velocity for at most that long, then freeze,
+//     positions are extrapolated along the last velocity for at most that long, then freeze — never for a unit the
+//     newest snapshot shows dead, stunned (frozen, asleep) or blocked, nor for an enemy it shows standing (`stand`),
 //   * sample(): per unit, lerps x/y/hp/sp between the two snapshots bracketing renderT; flags/anim come from
 //     the older one. A unit missing from the newer snapshot (died/left mid-buffer) holds its last position
 //     until renderT reaches the newer snapshot; a unit that only exists in the newer one (spawned mid-buffer)
@@ -20,18 +21,24 @@
 //     game s behind) are dropped by the caller's choice (`isCosmeticEvent`); state events — an enemy's form fx
 //     included — are always delivered, and a full queue sheds only cosmetic ones.
 //
-// Snapshot tuple layout (DESIGN §8.2): [id, x, y, hp, maxHp, sp, spMax, flags, anim]. Two optional lists ride along
-// (server/sim/battle/events.js snapshot, user playtest #4 items 8 / 9):
+// Snapshot tuple layout (DESIGN §8.2): [id, x, y, hp, maxHp, sp, spMax, flags, anim]. Optional lists ride along
+// (server/sim/battle/events.js snapshot; user playtest #4 items 8 / 9, PR #381):
 //   * `elem` [[id, element, fill, cooldownEnd, cooldown]] — the element gauge a unit shows: appended to that unit's
 //     normalised tuple (EL…EL_DUR) and handed out by sample() as `el`, `elFill`, `elUntil`, `elDur` (from the older
 //     snapshot, like flags);
 //   * `down` [[id, respawnAt, respawnTime, state, row?, col?]] — knocked-out operators waiting to redeploy (they are no
 //     longer in `units`) and the tile they lie on (where they fell, or their home — sim Battle._layBody; kept only when
-//     both are integers): downAt(time) returns the list of the snapshot at `time`.
-// Game times in both (`cooldownEnd`, `respawnAt`) are on the snapshots' clock, so a view compares them with renderT.
+//     both are integers): downAt(time) returns the list of the snapshot at `time`;
+//   * `stand` [[id, until]] — the game time an enemy's attack recovery ends (sim atkStandUntil, PR #381): the position
+//     holds until then and interpolates the rest of the interval; nothing is inferred from the attack animation, and a
+//     snapshot without it interpolates linearly;
+//   * `standCut` [[id, at]] — the latest time that enemy's recovery was cut or ignored: an interval with a cut inside
+//     it stays linear.
+// Game times in all of them (`cooldownEnd`, `respawnAt`, `until`, `at`) are on the snapshots' clock, so a view compares
+// them with renderT.
 
 import { fxForm } from '../../../shared/protocol.js';
-import { ANIM } from '../../../shared/constants.js';
+import { ANIM, UF } from '../../../shared/constants.js';
 
 export const TUPLE = Object.freeze({ ID: 0, X: 1, Y: 2, HP: 3, MAXHP: 4, SP: 5, SPMAX: 6, FLAGS: 7, ANIM: 8, EL: 9, EL_FILL: 10, EL_UNTIL: 11, EL_DUR: 12 });
 /** The unit was (re)deployed between tuples `a` and the newer `b`: `b` plays the deploy animation, `a` did not (sim snapshot animOf). */
@@ -43,6 +50,15 @@ const MAX_EVENTS = 6000;
 const finite = (v, d = 0) => (typeof v === 'number' && Number.isFinite(v) ? v : d);
 const clamp = (v, lo, hi) => (v < lo ? lo : v > hi ? hi : v);
 
+/**
+ * Game time unit `id` starts moving between snapshot `a` and the newer `b` (interpolation and extrapolation share it):
+ * the end of `a`'s stand when it falls inside the interval and `b` records no cut there, else `a.t`.
+ */
+function movementStart(a, b, id) {
+  const until = a.stand?.get(id), cutAt = b.standCut?.get(id);
+  return until > a.t && until <= b.t && !(cutAt >= a.t && cutAt <= b.t) ? until : a.t;
+}
+
 /** Cosmetic event kinds that may be dropped when far behind (never state-changing). */
 export const COSMETIC_EVENTS = new Set(['atk', 'dmg', 'heal', 'fx', 'layer', 'bounty']);
 /**
@@ -66,8 +82,9 @@ export function frameTime(msg) {
 
 /**
  * Validate & normalise a b.snap payload. Returns `{ t, units: Map<id, tuple>, down: [[id, respawnAt, respawnTime,
- * state, row?, col?]] | null, raw }` or null when unusable. Tuples with a non-finite id/x/y are skipped; other numbers default
+ * state, row?, col?]] | null, stand: Map<id, until> | null, standCut: Map<id, at> | null, raw }` or null when unusable. Tuples with a non-finite id/x/y are skipped; other numbers default
  * to 0; a unit's `elem` entry (see header) is appended to its tuple; malformed `elem` / `down` entries are dropped.
+ * `stand` keeps finite end times after `t` of units in the snapshot; `standCut` keeps finite times in [0, t] of units in it.
  */
 export function normalizeSnapshot(snap) {
   if (!snap || typeof snap !== 'object') return null;
@@ -99,7 +116,21 @@ export function normalizeSnapshot(snap) {
       (down || (down = [])).push(e);
     }
   }
-  return { t, units, down, raw: snap };
+  let stand = null;
+  if (Array.isArray(snap.stand)) {
+    for (const e of snap.stand) {
+      if (!Array.isArray(e) || !units.has(e[0]) || !Number.isFinite(e[1]) || e[1] <= t) continue;
+      (stand || (stand = new Map())).set(e[0], e[1]);
+    }
+  }
+  let standCut = null;
+  if (Array.isArray(snap.standCut)) {
+    for (const e of snap.standCut) {
+      if (!Array.isArray(e) || !units.has(e[0]) || !Number.isFinite(e[1]) || e[1] < 0 || e[1] > t) continue;
+      (standCut || (standCut = new Map())).set(e[0], e[1]);
+    }
+  }
+  return { t, units, down, stand, standCut, raw: snap };
 }
 
 export class SnapshotBuffer {
@@ -288,22 +319,30 @@ export class SnapshotBuffer {
         const dx = b[1] - a[1], dy = b[2] - a[2];
         // (a deployment in between — the newer snapshot starts its deploy animation — lands on its tile, no slide)
         const tele = dx * dx + dy * dy > this.teleport * this.teleport || redeployed(a, b);
-        o.x = tele ? (alpha < 1 ? a[1] : b[1]) : a[1] + dx * alpha;
-        o.y = tele ? (alpha < 1 ? a[2] : b[2]) : a[2] + dy * alpha;
-        o.vx = !tele && span > 0 ? dx / span : 0;
-        o.vy = !tele && span > 0 ? dy / span : 0;
+        const start = movementStart(A, B, id);
+        const moveSpan = B.t - start;
+        const moveAlpha = moveSpan > 0 ? clamp((time - start) / moveSpan, 0, 1) : 0;
+        o.x = tele ? (alpha < 1 ? a[1] : b[1]) : a[1] + dx * moveAlpha;
+        o.y = tele ? (alpha < 1 ? a[2] : b[2]) : a[2] + dy * moveAlpha;
+        o.vx = !tele && moveSpan > 0 && (start === A.t || time >= start) ? dx / moveSpan : 0;
+        o.vy = !tele && moveSpan > 0 && (start === A.t || time >= start) ? dy / moveSpan : 0;
         o.hp = a[3] + (b[3] - a[3]) * alpha;
         o.maxHp = b[4] || a[4];
         o.sp = a[5] + (b[5] - a[5]) * alpha;
         o.spMax = b[6] || a[6];
       } else {
         let vx = 0, vy = 0;
-        if (P && ext > 0) {
+        // a stand in the newest snapshot: the old velocity cannot predict the walk after it, even once the clock passes
+        // `until` — the next snapshot confirms the position
+        if (P && ext > 0 && a[8] !== ANIM.DIE && a[8] !== ANIM.STUN && !(a[7] & UF.BLOCKED) && !A.stand?.has(id)) {
           const p = P.units.get(id);
           const dtp = A.t - P.t;
-          if (p && dtp > 0) {
-            vx = (a[1] - p[1]) / dtp; vy = (a[2] - p[2]) / dtp;
-            if (vx * vx + vy * vy > (this.teleport / dtp) ** 2 || redeployed(p, a)) { vx = 0; vy = 0; }
+          const moveSpan = A.t - movementStart(P, A, id);
+          if (p && dtp > 0 && moveSpan > 0) {
+            const dx = a[1] - p[1], dy = a[2] - p[2];
+            if (dx * dx + dy * dy <= this.teleport * this.teleport && !redeployed(p, a)) {
+              vx = dx / moveSpan; vy = dy / moveSpan;
+            }
           }
         }
         o.x = a[1] + vx * ext;
diff --git a/server/sim/ai.js b/server/sim/ai.js
index c9a9f0eb..00f08b9e 100644
--- a/server/sim/ai.js
+++ b/server/sim/ai.js
@@ -535,6 +535,7 @@ export function updateEnemy(b, e, dt) {
   if (!e.alive) return;
   // hidden (teleporting) enemies only advance wait legs
   const stunned = e.s.flags.stun;
+  if (stunned || e.hidden || e.s.flags.fear) b._cutAttackStand(e);
   const prevCd = e.atkCd;
   if (e.atkCd > 0 && !stunned && !e.hidden) e.atkCd = Math.max(0, e.atkCd - dt);
   // a stun / freeze / sleep / 浮空 — or leaving the field — takes the enemy out of its attack: a swing short of its damage
@@ -644,6 +645,7 @@ function advanceRoute(b, e, dt, R, standing = false) {
       continue;
     }
     if (leg.t === 'disappear') {
+      b._cutAttackStand(e);
       b._setHidden(e, true);
       e.atkStandUntil = -Infinity; standing = false;   // off the field: its attack clip is over
       R.legIdx++; R.pts = null;
diff --git a/server/sim/battle/deploy.js b/server/sim/battle/deploy.js
index 3f991d9d..72a6a6c4 100644
--- a/server/sim/battle/deploy.js
+++ b/server/sim/battle/deploy.js
@@ -97,6 +97,7 @@ export class BattleDeploy {
   }
 
   _remove(unit, reason, killer = null, permanent = false, dying = false) {
+    this._cutAttackStand(unit);
     unit.alive = false;
     unit.removeReason = reason;
     unit.deployed = false;
diff --git a/server/sim/battle/displacement.js b/server/sim/battle/displacement.js
index 12a2cfc7..6c409430 100644
--- a/server/sim/battle/displacement.js
+++ b/server/sim/battle/displacement.js
@@ -141,6 +141,7 @@ export class BattleDisplacement {
     if (moved > 0) {
       this._unblock(e);
       // 失衡 ends the attack clip it stood for (PRTS 状态机: the states are exclusive — UNBALANCE, then DEFAULT → MOVE)
+      this._cutAttackStand(e);
       e.atkStandUntil = -Infinity;
       if (e.route) e.route.pts = null;
       this.fx('displace', { x: e.x, y: e.y, id: e.id });
diff --git a/server/sim/battle/events.js b/server/sim/battle/events.js
index 690b4c54..4a5a3199 100644
--- a/server/sim/battle/events.js
+++ b/server/sim/battle/events.js
@@ -32,12 +32,26 @@ export class BattleEvents {
     return ev;
   }
 
+  /**
+   * Record that an enemy's attack recovery (atkStandUntil) is cut or ignored now — snapshot `standCut`, display metadata
+   * (render/interp.js); never changes the attack's timing or state.
+   */
+  _cutAttackStand(unit) {
+    if (unit.side === 'enemy' && Number.isFinite(unit.atkStandUntil) && unit.atkStandUntil > this.time) {
+      unit.atkStandCutAt = this.time;
+    }
+  }
+
   /**
    * Compact full snapshot of this field (DESIGN §8.2 b.snap), plus (only when non-empty):
    *   down: [[id, respawnAt, respawnTime, state, row, col]] — operators that left the field waiting to redeploy (isDown): the
    *         game time their respawn timer ends, its length (s), constants.js DOWN_STATE and the tile they lie on (and
    *         come back on: _layBody — where they fell, or their home);
    *   elem: [[id, element, fill, cooldownEnd, cooldown]] — the element gauge each unit shows (damage.js elementView).
+   *   stand: [[id, until]] — when each enemy's attack recovery ends (atkStandUntil; alive, deployed, visible, not
+   *         feared or stunned) — display metadata (render/interp.js holds the position until then);
+   *   standCut: [[id, at]] — the latest time each listed enemy's recovery was cut or ignored (_cutAttackStand), the
+   *         dying ones in their death window included.
    */
   snapshot() {
     const snap = {
@@ -60,13 +74,24 @@ export class BattleEvents {
       (down || (down = [])).push([u.id, r2(u.respawnAt), r2(Math.max(0, u.respawnAt - u.deathAt)), this._downState(u), ...this.restTile(u)]);
     }
     if (down) snap.down = down;
-    let elem = null;
+    let elem = null, stand = null, standCut = null;
+    let listed = null;   // the ids in snap.units, built for the first enemy with a cut to report
     for (const u of this.units) {
+      if (u.side === 'enemy' && u.atkStandCutAt >= 0) {
+        const cutAt = Math.round(u.atkStandCutAt * 1000) / 1000;
+        if (cutAt <= snap.t && (listed || (listed = new Set(snap.units.map((x) => x[0])))).has(u.id)) (standCut || (standCut = [])).push([u.id, cutAt]);
+      }
       if (!u.alive || !u.deployed || u.hidden) continue;
+      const until = Math.round(u.atkStandUntil * 1000) / 1000;
+      if (u.side === 'enemy' && !u.s.flags.fear && !u.s.flags.stun && Number.isFinite(until) && until > snap.t) {
+        (stand || (stand = [])).push([u.id, until]);
+      }
       const v = elementView(u, this.time);
       if (v) (elem || (elem = [])).push([u.id, v[0], v[1], v[2], v[3]]);
     }
     if (elem) snap.elem = elem;
+    if (stand) snap.stand = stand;
+    if (standCut) snap.standCut = standCut;
     return snap;
   }
 
diff --git a/server/sim/battle/spawns.js b/server/sim/battle/spawns.js
index 17c1c5fd..761e162f 100644
--- a/server/sim/battle/spawns.js
+++ b/server/sim/battle/spawns.js
@@ -132,6 +132,7 @@ export class BattleSpawns {
     e.atkCd = 0;
     e.pauseUntil = -Infinity;      // content holds (暴鸰's drop)
     e.atkStandUntil = -Infinity;   // standing for its attack clip (ai.js attackStand)
+    e.atkStandCutAt = -Infinity;   // display metadata: when its stand was last cut or ignored (snapshot standCut)
     e.swing = false;               // a normal attack swung, its damage frame not reached yet (ai.js enemyAttack)
     // every enemy profile starts with the same fields (stable object shapes keep the hot loop's property reads fast);
     // `dmgType` null = the data's (content may arm a data-unarmed enemy: ai.js enemyAttack); `blockFree` = its 索敌不受阻挡
diff --git a/test/render/attack-recovery-interp.test.js b/test/render/attack-recovery-interp.test.js
new file mode 100644
index 00000000..d317cd1c
--- /dev/null
+++ b/test/render/attack-recovery-interp.test.js
@@ -0,0 +1,428 @@
+// 敌人普攻后摇：可选快照元数据的生产、校验与位置插值；不改动战斗规则。
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { SnapshotBuffer, normalizeSnapshot } from '../../public/js/render/interp.js';
+import { ANIM, UF } from '../../shared/constants.js';
+import { makeBattle, chessRec, checkInvariants } from '../helpers/battleHarness.js';
+import { snapFrame } from '../../server/match/fields.js';
+import { TICK } from '../../server/sim/constants.js';
+import { rupture } from '../../server/sim/content/kits/ops/op-weedy.js';
+
+const tuple = (x, anim = ANIM.ATTACK) => [1, x, 9, 100, 100, 0, 0, 0, anim];
+const frame = (t, x, until, anim) => ({ t, units: [tuple(x, anim)], ...(until === undefined ? {} : { stand: [[1, until]] }) });
+const near = (got, want) => assert.ok(Math.abs(got - want) < 1e-8, `${got} ≠ ${want}`);
+
+test('stand：仅保留快照中存在的单位与有限、未来的结束时间', () => {
+  const valid = normalizeSnapshot({ t: 'b.snap', gt: 1, units: [tuple(0)], stand: [
+    null, 'x', [1], [2, 2], [1, '2'], [1, NaN], [1, Infinity], [1, 1], [1, 0.9], [1, 1.08],
+  ] });
+  assert.deepEqual([...valid.stand], [[1, 1.08]]);
+  for (const stand of [undefined, null, {}, [], [[1, 1]], [[2, 2]]]) {
+    assert.equal(normalizeSnapshot({ t: 1, units: [tuple(0)], stand }).stand, null);
+  }
+});
+
+test('standCut：仅保留已有单位的有限、非负且不晚于快照的时间', () => {
+  const valid = normalizeSnapshot({ t: 'b.snap', gt: 1, units: [tuple(0)], standCut: [
+    null, 'x', [1], [2, 0.9], [1, '0.9'], [1, NaN], [1, Infinity], [1, -1], [1, 1.01], [1, 0.9],
+  ] });
+  assert.deepEqual([...valid.standCut], [[1, 0.9]]);
+  for (const standCut of [undefined, null, {}, [], [[1, -1]], [[2, 0]], [[1, 1.01]]]) {
+    assert.equal(normalizeSnapshot({ t: 1, units: [tuple(0)], standCut }).standCut, null);
+  }
+  assert.equal(normalizeSnapshot({ t: 1, units: [tuple(0)], standCut: [[1, 0], [1, 1]] }).standCut.get(1), 1);
+});
+
+test('后摇结束前保持位置，结束后插值剩余区间；HP/SP 仍按整段时间插值', () => {
+  const b = new SnapshotBuffer();
+  b.push(frame(1, 0, 1.08), 0);
+  const next = frame(1.1, 0.02, undefined, ANIM.MOVE);
+  next.units[0][3] = 50;
+  next.units[0][5] = 10;
+  b.push(next, 0.05);
+  for (const t of [1, 1.04, 1.079]) {
+    const s = b.sample(t).get(1);
+    assert.equal(s.x, 0);
+    assert.equal(s.vx, 0);
+    assert.equal(s.anim, ANIM.ATTACK);
+  }
+  const middle = b.sample(1.05).get(1);
+  near(middle.hp, 75);
+  near(middle.sp, 5);
+  near(b.sample(1.09).get(1).x, 0.01);
+  near(b.sample(1.09).get(1).vx, 1);
+  near(b.sample(1.1).get(1).x, 0.02);
+});
+
+test('旧快照、过期元数据及攻击→移动动画不推断停步', () => {
+  for (const until of [undefined, 0.9, 1, NaN, Infinity]) {
+    const b = new SnapshotBuffer();
+    b.push(frame(1, 0, until), 0);
+    b.push(frame(1.1, 0.1, undefined, ANIM.MOVE), 0.05);
+    near(b.sample(1.05).get(1).x, 0.05);
+    near(b.sample(1.05).get(1).vx, 1);
+  }
+});
+
+test('后摇结束时间恰为下一帧时，位置在该帧之前保持不动', () => {
+  const b = new SnapshotBuffer();
+  b.push(frame(1, 0, 1.1), 0);
+  b.push(frame(1.1, 0.02), 0.05);
+  assert.equal(b.sample(1.09).get(1).x, 0);
+  near(b.sample(1.1).get(1).x, 0.02);
+});
+
+test('后摇尚未到期但新帧已移动时，不阻止权威位置更新', () => {
+  const b = new SnapshotBuffer();
+  b.push(frame(1, 0, 2), 0);
+  b.push(frame(1.1, 0.1, undefined, ANIM.MOVE), 0.05);
+  near(b.sample(1.05).get(1).x, 0.05);
+});
+
+test('后摇结束时间落在两帧之间，但该区间有打断时，插值和外推均使用完整区间', () => {
+  for (const cutAt of [1, 1.04, 1.1]) {
+    const b = new SnapshotBuffer();
+    b.push(frame(1, 0, 1.08), 0);
+    b.push({ ...frame(1.1, 0.1, undefined, ANIM.MOVE), standCut: [[1, cutAt]] }, 0.05);
+    near(b.sample(1.05).get(1).x, 0.05);
+    near(b.sample(1.099).get(1).vx, 1);
+    near(b.sample(1.101).get(1).vx, 1);
+    near(b.sample(1.15).get(1).x, 0.15);
+  }
+});
+
+test('旧的打断记录不影响后续未被打断的后摇', () => {
+  const b = new SnapshotBuffer();
+  b.push(frame(1, 0, 1.08), 0);
+  b.push({ ...frame(1.1, 0.02), standCut: [[1, 0.9]] }, 0.05);
+  assert.equal(b.sample(1.04).get(1).x, 0);
+  near(b.sample(1.09).get(1).vx, 1);
+  near(b.sample(1.15).get(1).vx, 1);
+});
+
+test('后摇恢复段进入外推时速度连续，零长度移动区间不产生无穷速度', () => {
+  const b = new SnapshotBuffer();
+  b.push(frame(1, 0, 1.08), 0);
+  b.push(frame(1.1, 0.02, undefined, ANIM.MOVE), 0.05);
+  near(b.sample(1.099).get(1).vx, 1);
+  near(b.sample(1.101).get(1).vx, 1);
+  near(b.sample(1.15).get(1).x, 0.07);
+  const edge = new SnapshotBuffer();
+  edge.push(frame(1, 0, 1.1), 0);
+  edge.push(frame(1.1, 0.02), 0.05);
+  near(edge.sample(1.15).get(1).x, 0.02);
+  assert.equal(edge.sample(1.15).get(1).vx, 0);
+});
+
+test('停步期间及网络停顿越过结束时间后，都不使用攻击前的速度外推', () => {
+  const b = new SnapshotBuffer({ maxExtrapolate: 0.2 });
+  b.push(frame(0.9, -0.1), 0);
+  b.push(frame(1, 0, 1.08), 0.05);
+  for (const t of [1.04, 1.09, 5]) {
+    const s = b.sample(t).get(1);
+    assert.equal(s.x, 0);
+    assert.equal(s.vx, 0);
+  }
+  b.push(frame(1.1, 0.02, undefined, ANIM.MOVE), 0.1);
+  assert.ok(b.sample(1.15).get(1).x > 0.02, '新位置确认后恢复原有外推');
+});
+
+test('瞬移与重新部署的跳转优先于后摇插值', () => {
+  for (const [x, anim] of [[8, ANIM.MOVE], [0.1, ANIM.DEPLOY]]) {
+    const b = new SnapshotBuffer({ teleport: 2 });
+    b.push(frame(1, 0, 1.04), 0);
+    b.push(frame(1.1, x, undefined, anim), 0.05);
+    assert.equal(b.sample(1.09).get(1).x, 0);
+    near(b.sample(1.1).get(1).x, x);
+    assert.equal(b.sample(1.09).get(1).vx, 0);
+    near(b.sample(1.15).get(1).x, x);
+    assert.equal(b.sample(1.15).get(1).vx, 0);
+  }
+});
+
+test('死亡或眩晕的最新帧不沿用旧速度外推；恢复移动后仍可外推', () => {
+  for (const anim of [ANIM.DIE, ANIM.STUN]) {
+    const b = new SnapshotBuffer();
+    b.push(frame(0.9, -0.1, undefined, ANIM.MOVE), 0);
+    const stopped = frame(1, 0, undefined, anim);
+    if (anim === ANIM.DIE) stopped.units[0][3] = 0;
+    b.push(stopped, 0.05);
+    for (const t of [1.01, 1.24, 5]) {
+      assert.equal(b.sample(t).get(1).x, 0);
+      assert.equal(b.sample(t).get(1).vx, 0);
+    }
+    b.push(frame(1.1, 0.02, undefined, ANIM.MOVE), 0.1);
+    near(b.sample(1.15).get(1).x, 0.03);
+  }
+});
+
+test('最新帧中已消失的单位不外推，并从复用的采样结果中删除', () => {
+  const b = new SnapshotBuffer(), out = new Map();
+  b.push(frame(0.9, -0.1, undefined, ANIM.MOVE), 0);
+  b.push(frame(1, 0, 1.08), 0.05);
+  b.push({ t: 1.1, units: [] }, 0.1);
+  assert.equal(b.sample(1.05, out).get(1).x, 0);
+  assert.equal(b.sample(1.05, out).get(1).vx, 0);
+  assert.equal(b.sample(1.2, out).has(1), false);
+});
+
+function arena(key, wallRow = 10) {
+  return makeBattle({
+    defs: { chess: { t_wall: chessRec({ id: 't_wall', stats: { maxHp: 1e9, atk: 0, def: 1e6 }, skill: null }) } },
+    units: [{ chessId: 't_wall', row: wallRow, col: 6 }],
+    enemies: [{ key, time: 0, route: 0 }],
+    content: 'none', autoFinish: false, timeLimit: 60,
+  });
+}
+
+test('真实隐形弩手：Battle → b.snap → SnapshotBuffer 在后摇结束前不滑动', () => {
+  const h = arena('enemy_1019_jshoot');
+  let prev, pair;
+  for (let i = 0; i < 1200 && !pair; i++) {
+    h.step();
+    if (i % 3 !== 2) continue;
+    const next = h.b.snapshot();
+    const e = h.enemy('enemy_1019_jshoot');
+    const a = prev?.units.find((u) => u[0] === e.id), z = next.units.find((u) => u[0] === e.id);
+    const until = prev?.stand?.find((v) => v[0] === e.id)?.[1];
+    if (a && z && until > prev.t && until < next.t && (a[1] !== z[1] || a[2] !== z[2])) pair = { a, z, until, prev, next };
+    prev = next;
+  }
+  assert.ok(pair, '真实攻击后摇跨越两帧且随后恢复移动');
+  const { a, z, until, prev: A, next: B } = pair;
+  const b = new SnapshotBuffer();
+  b.push(snapFrame('test', A), 0);
+  b.push(snapFrame('test', B), 0.05);
+  const held = b.sample((A.t + until) / 2).get(a[0]);
+  assert.equal(held.x, a[1]);
+  assert.equal(held.y, a[2]);
+  assert.equal(held.vx, 0);
+  const moved = b.sample((until + B.t) / 2).get(a[0]);
+  near(moved.x, (a[1] + z[1]) / 2);
+  near(moved.y, (a[2] + z[2]) / 2);
+  near(b.sample(B.t - 1e-6).get(a[0]).vx, b.sample(B.t + 1e-6).get(a[0]).vx);
+  checkInvariants(h.b);
+  assert.equal(h.b.errors.length, 0);
+});
+
+test('真实隐形弩手：失衡跨帧打断时不按旧后摇时间冻结和集中追赶', () => {
+  const h = arena('enemy_1019_jshoot');
+  assert.ok(h.runUntil(() => {
+    const e = h.enemy('enemy_1019_jshoot');
+    return e && e.atkStandUntil - h.b.time > TICK && e.atkStandUntil - h.b.time < 3 * TICK;
+  }, 10));
+  const e = h.enemy('enemy_1019_jshoot'), A = h.b.snapshot();
+  const until = A.stand.find((s) => s[0] === e.id)[1];
+  h.step();
+  const cutAt = Math.round(h.b.time * 1000) / 1000;
+  assert.ok(h.b.displace(e, { x: -1, y: 0 }, 0.6) > 0);
+  h.step(2);
+  const B = h.b.snapshot();
+  assert.ok(until > A.t && until < B.t);
+  assert.equal(B.standCut.find((s) => s[0] === e.id)[1], cutAt);
+  const b = new SnapshotBuffer();
+  b.push(snapFrame('test', A), 0);
+  b.push(snapFrame('test', B), 0.05);
+  const a = A.units.find((u) => u[0] === e.id), z = B.units.find((u) => u[0] === e.id);
+  near(b.sample((A.t + B.t) / 2).get(e.id).x, (a[1] + z[1]) / 2);
+  near(b.sample(B.t + 1e-6).get(e.id).vx, (z[1] - a[1]) / (B.t - A.t));
+  checkInvariants(h.b);
+  assert.equal(h.b.errors.length, 0);
+});
+
+test('真实隐形弩手：后摇中击退并被移动创伤击杀，死亡帧保留打断且尸体不外推', () => {
+  const h = arena('enemy_1019_jshoot');
+  assert.ok(h.runUntil(() => {
+    const e = h.enemy('enemy_1019_jshoot');
+    return e && e.atkStandUntil - h.b.time > TICK && e.atkStandUntil - h.b.time < 3 * TICK;
+  }, 10));
+  const e = h.enemy('enemy_1019_jshoot'), A = h.b.snapshot();
+  const until = A.stand.find((s) => s[0] === e.id)[1];
+  h.step();
+  const cutAt = Math.round(h.b.time * 1000) / 1000;
+  // 温蒂的真实移动创伤实现：击退后下一次伤害结算在同一个快照间隔内击杀目标。
+  rupture(h.b, h.unit('t_wall'), e, { duration: 5, perTile: 1e6, interval: TICK });
+  near(h.b.push(e, e.s.massLevel + 1, { dir: { x: -1, y: 0 }, fixed: true }), 2.14);
+  h.step(2);
+  const B = h.b.snapshot();
+  assert.equal(e.alive, false);
+  assert.ok(until > A.t && until < B.t);
+  assert.equal(B.standCut?.find((s) => s[0] === e.id)?.[1], cutAt);
+  assert.equal(B.stand?.some((s) => s[0] === e.id) ?? false, false);
+  const a = A.units.find((u) => u[0] === e.id), z = B.units.find((u) => u[0] === e.id);
+  assert.equal(z[8], ANIM.DIE);
+  const b = new SnapshotBuffer();
+  b.push(snapFrame('test', A), 0);
+  b.push(snapFrame('test', B), 0.05);
+  near(b.sample((A.t + B.t) / 2).get(e.id).x, (a[1] + z[1]) / 2);
+  for (const t of [B.t, B.t + 0.01, B.t + 0.24, B.t + 1]) {
+    assert.equal(b.sample(t).get(e.id).x, z[1]);
+    assert.equal(b.sample(t).get(e.id).vx, 0);
+  }
+  b.update(0.05);
+  for (let i = 1; i <= 90; i++) b.update(0.05 + i / 120);
+  assert.ok(b.renderT > B.t);
+  assert.equal(b.sample().get(e.id).x, z[1]);
+  h.run(0.9);
+  const C = h.b.snapshot();
+  assert.equal(C.units.some((u) => u[0] === e.id), false);
+  assert.equal(C.standCut?.some((s) => s[0] === e.id) ?? false, false);
+  b.push(snapFrame('test', C), 0.5);
+  assert.equal(b.sample(C.t + 0.1).has(e.id), false);
+  checkInvariants(h.b);
+  assert.equal(h.b.errors.length, 0);
+});
+
+test('真实隐形弩手：AI 更新前死亡也记录后摇终止，隐藏和死亡窗口外不发送记录', () => {
+  const h = arena('enemy_1019_jshoot');
+  assert.ok(h.runUntil(() => h.enemy('enemy_1019_jshoot')?.atkStandUntil > h.b.time + 0.1, 10));
+  const e = h.enemy('enemy_1019_jshoot');
+  const at = Math.round(h.b.time * 1000) / 1000;
+  h.b.kill(e, h.unit('t_wall'));
+  assert.equal(Math.round(e.atkStandCutAt * 1000) / 1000, at);
+  assert.deepEqual(h.b.snapshot().standCut, [[e.id, at]]);
+  e.hidden = true;
+  assert.equal(h.b.snapshot().standCut, undefined);
+  e.hidden = false;
+  h.run(0.9);
+  assert.equal(h.b.snapshot().standCut, undefined);
+  checkInvariants(h.b);
+  assert.equal(h.b.errors.length, 0);
+});
+
+for (const status of ['stun', 'freeze', 'sleep', 'levitate']) {
+  test(`真实隐形弩手：移动后${status}的最新帧不继续滑动，解除后恢复移动`, () => {
+    const h = arena('enemy_1019_jshoot');
+    h.step(3);
+    const e = h.enemy('enemy_1019_jshoot'), A = h.b.snapshot();
+    h.step();
+    assert.equal(h.b.applyStatus(e, status, { duration: 1, force: true, source: h.unit('t_wall') }), true);
+    h.step(2);
+    const B = h.b.snapshot(), z = B.units.find((u) => u[0] === e.id);
+    assert.equal(z[8], ANIM.STUN);
+    assert.notEqual(A.units.find((u) => u[0] === e.id)[1], z[1]);
+    const b = new SnapshotBuffer();
+    b.push(snapFrame('test', A), 0);
+    b.push(snapFrame('test', B), 0.05);
+    assert.equal(b.sample(B.t + 0.1).get(e.id).x, z[1]);
+    assert.equal(b.sample(B.t + 0.1).get(e.id).vx, 0);
+    h.run(1.1);
+    const C = h.b.snapshot();
+    assert.equal(e.s.flags.stun, false);
+    assert.ok(C.units.find((u) => u[0] === e.id)[1] < z[1]);
+    b.push(snapFrame('test', C), 0.6);
+    assert.ok(b.sample(C.t + 0.1).get(e.id).vx < 0);
+    checkInvariants(h.b);
+    assert.equal(h.b.errors.length, 0);
+  });
+}
+
+test('真实隐形弩手：刚被阻挡的最新帧不继续滑动，阻挡者离场后恢复移动', () => {
+  const h = arena('enemy_1019_jshoot', 9);
+  let prev, pair;
+  for (let i = 0; i < 1200 && !pair; i++) {
+    h.step();
+    if (i % 3 !== 2) continue;
+    const next = h.b.snapshot(), e = h.enemy('enemy_1019_jshoot');
+    const a = prev?.units.find((u) => u[0] === e.id), z = next.units.find((u) => u[0] === e.id);
+    if (a && z && (z[7] & UF.BLOCKED) && a[1] !== z[1] && !next.stand?.some((s) => s[0] === e.id)) pair = { A: prev, B: next, e, z };
+    prev = next;
+  }
+  assert.ok(pair, '移动与首次阻挡发生于同一个快照间隔，且没有后摇元数据');
+  const { A, B, e, z } = pair;
+  const b = new SnapshotBuffer();
+  b.push(snapFrame('test', A), 0);
+  b.push(snapFrame('test', B), 0.05);
+  assert.equal(b.sample(B.t + 0.24).get(e.id).x, z[1]);
+  assert.equal(b.sample(B.t + 0.24).get(e.id).vx, 0);
+  h.b.retreat(h.unit('t_wall'), { permanent: true });
+  h.step(3);
+  const C = h.b.snapshot();
+  assert.equal(e.blockedBy, null);
+  assert.ok(C.units.find((u) => u[0] === e.id)[1] < z[1]);
+  b.push(snapFrame('test', C), 0.1);
+  assert.ok(b.sample(C.t + 0.1).get(e.id).vx < 0);
+  checkInvariants(h.b);
+  assert.equal(h.b.errors.length, 0);
+});
+
+test('真实隐形弩手：恐惧打断在延迟帧之后仍恢复线性插值', () => {
+  const h = arena('enemy_1019_jshoot');
+  assert.ok(h.runUntil(() => {
+    const e = h.enemy('enemy_1019_jshoot');
+    return e && e.atkStandUntil - h.b.time > 4 * TICK && e.atkStandUntil - h.b.time < 5 * TICK;
+  }, 10));
+  const e = h.enemy('enemy_1019_jshoot'), A = h.b.snapshot();
+  const until = A.stand.find((s) => s[0] === e.id)[1];
+  h.step();
+  assert.equal(h.b.applyStatus(e, 'fear', { duration: 1, source: h.unit('t_wall') }), true);
+  // 本地 runner 在卡帧时会推进多个 tick 后再发出一帧。
+  h.step(5);
+  const B = h.b.snapshot();
+  assert.ok(e.s.flags.fear && until > A.t && until < B.t);
+  assert.ok(B.standCut.some((s) => s[0] === e.id && s[1] >= A.t));
+  const b = new SnapshotBuffer();
+  b.push(snapFrame('test', A), 0);
+  b.push(snapFrame('test', B), (B.t - A.t) / 2);
+  const a = A.units.find((u) => u[0] === e.id), z = B.units.find((u) => u[0] === e.id);
+  const s = b.sample((A.t + until) / 2).get(e.id);
+  const alpha = (until - A.t) / (2 * (B.t - A.t));
+  near(s.x, a[1] + (z[1] - a[1]) * alpha);
+  assert.ok(s.x > a[1]);
+  checkInvariants(h.b);
+  assert.equal(h.b.errors.length, 0);
+});
+
+test('真实枯朽之种：命中帧即动画末尾，没有后摇时仍连续移动', () => {
+  const h = arena('enemy_1269_nhfly');
+  let prev, checked = false;
+  for (let i = 0; i < 1200 && !checked; i++) {
+    h.step();
+    if (i % 3 !== 2) continue;
+    const next = h.b.snapshot();
+    const e = h.enemy('enemy_1269_nhfly');
+    assert.ok(!next.stand?.some((s) => s[0] === e.id), '零后摇不发送 stand');
+    const a = prev?.units.find((u) => u[0] === e.id), z = next.units.find((u) => u[0] === e.id);
+    if (a && z && a[8] === ANIM.ATTACK && z[8] === ANIM.MOVE && (a[1] !== z[1] || a[2] !== z[2])) {
+      const b = new SnapshotBuffer();
+      b.push(prev, 0);
+      b.push(next, 0.05);
+      const s = b.sample((prev.t + next.t) / 2).get(e.id);
+      near(s.x, (a[1] + z[1]) / 2);
+      near(s.y, (a[2] + z[2]) / 2);
+      checked = true;
+    }
+    prev = next;
+  }
+  assert.ok(checked, '真实攻击→移动帧对');
+  assert.equal(h.b.errors.length, 0);
+});
+
+test('快照不泄漏无效后摇：盟友、隐藏、未部署、死亡、恐惧、眩晕、到期及失衡打断', () => {
+  const h = arena('enemy_1019_jshoot');
+  assert.ok(h.runUntil(() => h.enemy('enemy_1019_jshoot')?.atkStandUntil > h.b.time + 0.1, 10));
+  const e = h.enemy('enemy_1019_jshoot');
+  const has = () => h.b.snapshot().stand?.some((s) => s[0] === e.id) ?? false;
+  assert.ok(has());
+  const ally = h.unit('t_wall');
+  ally.atkStandUntil = e.atkStandUntil;
+  assert.ok(!h.b.snapshot().stand.some((s) => s[0] === ally.id));
+  for (const key of ['hidden', 'alive', 'deployed']) {
+    const old = e[key];
+    e[key] = key === 'hidden';
+    assert.equal(has(), false, key);
+    e[key] = old;
+  }
+  for (const key of ['fear', 'stun']) {
+    e.s.flags[key] = true;
+    assert.equal(has(), false, key);
+    e.s.flags[key] = false;
+  }
+  for (const until of [h.b.time, -Infinity, NaN, Infinity]) {
+    e.atkStandUntil = until;
+    assert.equal(has(), false);
+  }
+  e.atkStandUntil = h.b.time + 1;
+  assert.ok(h.b.displace(e, { x: -1, y: 0 }, 0.2) > 0, '实际发生位移');
+  assert.equal(has(), false, '失衡已清除后摇');
+});
diff --git a/types/core.js b/types/core.js
index effe5f3a..f4ac108f 100644
--- a/types/core.js
+++ b/types/core.js
@@ -91,7 +91,9 @@
 /**
  * `snapshot()` (SIM §9). On the wire this object is the payload of `b.snap`,
  * and `t` is sent as `gt` because the frame's `t` is the message type (DESIGN §8.2).
- * `dp` is one number. `down` and `elem` are omitted when empty.
+ * `dp` is one number. `down`, `elem`, `stand` and `standCut` are omitted when empty: `stand` [id, until] = the game
+ * time an enemy's attack recovery ends, `standCut` [id, at] = the latest time it was cut or ignored (enemies in the
+ * snapshot's death window included).
  *
  * @typedef {Object} FieldSnapshot
  * @property {string} fieldId
@@ -104,6 +106,8 @@
  * @property {Object} [boss]
  * @property {DownSnap[]} [down]
  * @property {ElemSnap[]} [elem]
+ * @property {[number, number][]} [stand]
+ * @property {[number, number][]} [standCut]
  */
 
 /**

From 2669b6ab57d433850785c7548937f63ef9de2239 Mon Sep 17 00:00:00 2001
From: xcdoge <xcdoge@users.noreply.github.com>
Date: Thu, 8 Oct 2026 19:08:27 +0800
Subject: [PATCH 3/7] feedback7 R22-RENDER: a pushed / pulled enemy slides to
 where the sim put it, a dying flyer keeps its lift through the Die clip, a
 long Die clip plays whole (PR #380 by @xcdoge); golden: unchanged
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The sim displaces at once (battle/displacement.js), so the snapshots only show the destination: a ≤ 2.5-tile push was
lerped over one snapshot interval (3 frames, 0.58 tiles in one frame — frame-loop repro over a real battle), a longer
pull snapped. render/app.js now starts UnitView.slideTo as soon as the interval it samples ends on the snapshot that
carries the destination (a `displace` fx still queued up to SnapshotBuffer.nextSnapT); the view holds where it stood
until that snapshot is shown, then eases into the sampled position under a constant deceleration (v0 = 2D/T, a = v0/T,
T = 0.14·√D in 0.12–0.45 s — ours, [ASSUMED]: no source gives the official timing; docs/research/13 has the official
impulse-and-friction classes). A unit that dies on the way finishes the slide and lies where the push put it.
Death: DIE_CLIP_MAX 1.6 → 8 s (data/assets.json: 234 enemy Die clips, the longest 7.97 s, 25 over 1.6 s), and a
flyer holds FLY_HOVER until the fade tail (DIE_FADE_TAIL 0.55 s).

Substantially @xcdoge's code (PR #380: the slide, the death timing, research 13 / 14, most tests), authored as theirs.
Changed on review: the corpse no longer goes back to where it stood (the PR's test asserted that; the sim's body is at
the destination); the PR's pre-pass scanned (renderT − 0.5, renderT] after processEvents had taken those events, so
it never fired and the slide started a frame before landing — it now looks ahead to the next snapshot and holds the
view until then; the slide eases into the live sample instead of the fixed destination (no jump back onto an enemy
that walked on); each step uses its mean velocity (the end-of-step speed ran 9 % short, then jumped); the constants'
comments say the timing is ours; research 14 no longer cites a sweep script and a data guard that were not in the PR.

Golden: unchanged (client only).

Tests: test/render/unitview.test.js 35/35 (slide: deceleration, idempotence, facing, snapshots in flight, friction,
√D, corpse lies where pushed, hold-then-ease without a landing jump, a never-shown slide handed back; the app.js frame
order over a real battle: a 1.7-tile push over ≥ 8 frames with every step < 0.35 tiles, a push-kill's body staying at
the destination; death: a dying flyer's lift, every Die clip within DIE_CLIP_MAX and a 7.97 s clip scheduled whole);
test/sim/displace-fx.test.js 1/1; render/interp 16/16; docs tests pass.
---
 docs/research/00-INDEX.md              |   2 +
 docs/research/13-knockback-official.md | 134 ++++++++++++
 docs/research/14-death-animations.md   | 109 ++++++++++
 public/js/render/app.js                |  22 ++
 public/js/render/interp.js             |  10 +
 public/js/render/units.js              | 108 +++++++++-
 test/render/unitview.test.js           | 274 +++++++++++++++++++++++++
 test/sim/displace-fx.test.js           |  33 +++
 8 files changed, 686 insertions(+), 6 deletions(-)
 create mode 100644 docs/research/13-knockback-official.md
 create mode 100644 docs/research/14-death-animations.md
 create mode 100644 test/sim/displace-fx.test.js

diff --git a/docs/research/00-INDEX.md b/docs/research/00-INDEX.md
index 64a68fa8..0f4d19c7 100644
--- a/docs/research/00-INDEX.md
+++ b/docs/research/00-INDEX.md
@@ -19,6 +19,8 @@ Tags: **[DATA]** client game data · **[VERIFIED]** official or wiki rule text,
 | `07-assets.md` / `07-assets.json` | Verified URL patterns and resolved URLs for avatars, portraits, skills, bond/item/band icons, UI, Spine (ops + enemies), BGM/SFX, fonts; build plan. Addendum: spot check 40/40 OK. | `operators[*]`, `enemies[*]`, `bonds`, `items`, `bands`, `autochessUi`, `audio` |
 | `11-limits-official.md` | Official limits read from the client (2.7.71 il2cpp) and the community: bond layers cap at **999** per bond (`MAX_GARRISON_STACK`, `AddBondCount` = min(L + n, 999)); in boss battles outside training a single hit of **≥ 300000** on a leader (`IsBossEnemy` = an `autoChessData.bossInfoDict` enemyId) is **cancelled** ("限伤", `MAX_BATTLE_DAMAGE`); implemented in DESIGN §20.12. | `shared/constants.js BOND_LAYER_CAP / BOSS_HIT_LIMIT` |
 | `12-flying-visuals-official.md` | Official flying visuals and model placement, read from the client (PR #211 by @xcdoge; ported into 0.2.0 by the owner's decision of 2026-10-06): the fly offset is the single model-independent constant **0.35** (`CharacterAnimator..ctor` stores `Vector3(0,0.35,0)` at field +0x114; `_SetFlyMountPointOffset` / `_SetFlyHitOffset` add it while flying, negate it on landing) — in the client's *character* space, whose unit is the standard prefab scale 0.27, so **0.35 / 0.27 ≈ 1.3 tiles**, confirmed by pixel-measuring an official screenshot (1.2–1.4). `FLY_HOVER` 0.32 → **1.3**, flat (no per-model term). The same sweep found two model quirks: `modelScaleY` 1.263 (帝国炮火先兆者 pair, vertically stretched) and `mirrorX` (木制瑞印, mirrored prefab). | `public/js/render/units.js FLY_HOVER / enemyModelScaleY`, `data/enemies.json`, `tools/local-extract/enemy_model_offsets.py` |
+| `13-knockback-official.md` | Push / pull (推拉) in the official client (PR #380 by @xcdoge; written in Chinese): the knockback abilities (`Knockback`, `KnockBackWithDirection`, `KnockBackWithCharacterDirection`, `DragTowardSource`) carry an impulse (`m_force`) and a velocity decaying under friction (`m_friction*`, the tile's `additionalFriction` — `GrasslandType` NORMAL_LAND / ICE_LAND / SLIME_LAND); the data has no `move_duration` / `move_distance` key (distances are emergent; 力度 comes from `skill_table` / `enemy_database`); every tile of this mode's 11 maps is normal land. Also noted, not modelled: wall bounces (`_bounceTimesAsDamageTimes`) and `unbalanceProtectDueTime`. The client's slide (`v0 = 2D/T`, `a = v0/T`, T = 0.14·√D in 0.12–0.45 s) is ours [ASSUMED: no source gives the official timing]. | `render/units.js DISPLACE_SLIDE / slideTo`, `render/app.js` `displace` fx |
+| `14-death-animations.md` | Enemy death animations (PR #380 by @xcdoge): the art never drops the body (the PR author's 234-clip sweep — no Die/Idle/Move/Attack clip translates the root), the 1.6 s death cap cut 25 clips short (盐风主教昆图斯 7.97 s) so it is 8 s, and a flying unit keeps its lift for the whole Die clip, dropping only inside the fade tail (the client removes its fly offset in `CharacterAnimator.OnFinish`). | `render/units.js DIE_CLIP_MAX / DIE_FADE_TAIL` |
 
 ## 2. Match structure
 
diff --git a/docs/research/13-knockback-official.md b/docs/research/13-knockback-official.md
new file mode 100644
index 00000000..19d20d2d
--- /dev/null
+++ b/docs/research/13-knockback-official.md
@@ -0,0 +1,134 @@
+# 13 · 推拉（击退 / 拖拽）的官方实现：冲量 + 摩擦
+
+这份文档回答两个问题：**官方推拉到底怎么动**，以及**摩擦是谁的参数**。结论全部来自官方客户端本体的
+`global-metadata.dat`（il2cpp 元数据）、官方 gamedata（社区镜像 Kengxxiao/ArknightsGameData）与官方 AB 资源包，
+并附上每一步的验证方式，便于复核。
+
+## 0. 结论速览
+
+| 问题 | 答案 |
+|---|---|
+| 官方怎么动 | **冲量 + 摩擦**：给被推者一个力（`m_force` / `m_forceVectorX/Y`），速度**逐帧被摩擦衰减**直到停下 |
+| 有固定时长/距离吗 | **没有**：数据里不存在 `move_duration` / `move_distance` / `move_tiles` 键（`moveDuration`、`moveTiles` 属于 UI 类）⇒ 位移量是**涌现**的，这也是社区只能给出"**推力-位移近似对应表**"的原因 |
+| "力度"从哪来 | **官方数据**：`skill_table.json` 的 blackboard `force`（41 个技能带它），敌人侧在 `enemy_database.json`（8 条） |
+| 摩擦是谁的参数 | **地板（地形）+ 单位质量**，**不是**技能参数：`GrasslandType { NORMAL_LAND, ICE_LAND, SLIME_LAND }`，每格是一条 `GrasslandData { modeIdx, grasslandType, additionalFriction }`，运行时还会被 `UpdateFrictionFactor` / `RestoreFrictionFactor` 临时改写 |
+| 卫戍协议里有几种地板 | **实际只有普通地面**：11 张地图共 18 种格子字符，无冰面/黏液 ⇒ 本模式下摩擦恒定，滑行时长**不必按地板分档** |
+| 飞行目标怎么算 | **没有独立的空中摩擦**（`boatAirFactor` / `m_airBase` 属于"船"玩法）：飞行用的是**同一套**公式（单位摩擦 × 所在格子的 `additionalFriction`）；差别只在**运动模式**（`ENEMY_MOTION_TYPE_FLY`、`HEIGHT_CHANGED_TO_FLY_BLOCK_MOTION_MODE` ⇒ 忽略地面阻挡），以及**失衡免疫 / 静态刚体**的空中单位根本不可位移 |
+| 曲线形状 | 恒定减速 ⇒ `d/D = 2k − k²`（ease-out quad）、`T ∝ √D`；客户端用的 `T = 0.14·√D`（夹 0.12–0.45 s）是我们拟定的 [ASSUMED]，没有来源给出官方时长 |
+
+## 1. 官方类与字段（`global-metadata.dat`）
+
+推拉能力的类簇（与 PRTS 的"推与拉"术语逐字对应）：
+
+```
+Knockback · KnockBackWithDirection · KnockBackWithCharacterDirection · KnockBackTargetsByRootTile · DragTowardSource
+_decreaseForceLevelWhenNotInDirection（PRTS"特殊修正"−2 力度）· _dontChangeFaceByDirection · _GetPushDir
+TOO_CLOSE_TOLERANCE_SQR（PRTS"< 0.25 格转径向"）
+```
+
+运动学字段（同一批类里）：
+
+```
+m_force · m_forceVectorX/Y · forceScale · m_mass · m_velocity · get_mass · get_rigidbody2D
+m_friction · m_frictionBase · m_frictionFactor · get_frictionFactor · m_frictionFactorAdditional · get_additionalFriction
+UpdateFrictionFactor · RestoreFrictionFactor · _UpdateFrictionFactorAdditional · RestoreCached…
+_ApplyForce · _UpdateVelocityAndPos · _UpdateAllUnitDeltaPos · _GetForceByDirectionAndDamage
+m_bounceFrictionFactor · bounce · bounceease · _bounceTimesAsDamageTimes · _bounceBBKey · _bounceConditionValidator
+unbalanceProtectDueTime
+```
+
+⇒ `m_force*`（冲量）+ `m_velocity` / `_UpdateVelocityAndPos`（逐帧速度积分）+ `m_friction*`（衰减）就是"冲量 + 摩擦"；
+`UpdateFrictionFactor` / `RestoreFrictionFactor`（改完还要还原）说明摩擦**由外部临时提供**，不是能力自带。
+
+## 2. 地板（地形）摩擦
+
+地板系统就在**卫戍协议自己的格子类**里（同簇可见 `TileState { SHARED, MY_SIDE, MATE_SIDE }`、
+`CooperateStartTile` / `CooperateEndTile` / `CoopFootballTile`、`get_modeIndex` / `get_tilePlayerSide` /
+`_OnPlayerDying` / `_OnPlayerRevive`）：
+
+```
+_grasslandDatas · GrasslandType { NORMAL_LAND, ICE_LAND, SLIME_LAND } · GrasslandData { modeIdx, grasslandType, additionalFriction }
+DynamicBuffQuickSandTile（流沙）· DynamicBuffTile · DirectionTile（带方向的格子）
+```
+
+⇒ 每格可带 `additionalFriction`，即"**地板提供摩擦**"。另有冰面相关因子（`iceFactor`、`iceTile`、`OnIce`、`Frozen`）
+与"船/水/空"那套（`m_boatFrictionFactor`、`m_boatAirFactor`、`m_airBase`、`m_waterFlowForce*` —— 属于多索雷斯船玩法，
+**不是**飞行单位）。
+
+### 卫戍协议实际用到哪些地板
+
+`docs/research/05-maps.json`（11 张地图）里出现过的全部格子字符：
+
+```
+# ×1776（墙/虚空）  r ×580（道路）  X ×477（分区隔断）  f ×448（地面）  a ×330  b ×250  A ×165
+p ×77（预览栏）  d ×76（装置）  S ×66（起点）  I / E ×33（路线起/终）  h ×24（手牌栏）  O ×22  m ×12  i ×8  g ×8  R ×4
+```
+
+**没有冰面或黏液** ⇒ 本模式下所有可站地板摩擦一致。
+
+## 3. 力度来自官方数据（不是我们拟定的）
+
+`excel/skill_table.json` 的 blackboard 里 **`force` 出现 357 次、41 个技能**，例如：
+
+| 技能 | 名称 | 力度（按等级） |
+|---|---|---|
+| `skchr_weedy_1` / `_3` | 温蒂 炮管敲击 / 液氮大炮 | 0,1,2 / 1,2,3 |
+| `skchr_forcer_1` / `_2` | 见行者 护身射击 / 惊爆射击 | 0,1,2 / 1,2,3 |
+| `skchr_panda_1` / `_2` | 食铁兽 铁意六合 / 崩拳式 | 0,1,2 / 1,2,3 |
+| `skchr_rope_1` / `_2` | 崖心 勾爪发射 / 复式勾爪 | 0,1,2 / 0,1,2 |
+| `skchr_glady_1` / `_3` | 歌蕾蒂娅 缺水的大洋裂断 / 缺水的碎漩狂舞 | 0,1,2 / 0,1,2 |
+| `skchr_sqrrel_1` / `_2` | 阿消 水蒸气泵 / 高压水炮 | 0,1,2 / 0,1,2 |
+| `skchr_moeshd_2` | 可颂 磁爆锤 | 1,2,3 |
+| `sktok_archook` | 钩索 token 发射 | **11** |
+
+同一张表里 **没有** `friction` / `mass` / `knockback` 键 ⇒ **力度是数据（可查表），摩擦与质量在引擎里**。
+
+### 靠"职业"就能推拉的干员
+
+`character_table.json` 的 `subProfessionId` 有两个专门职业，**普通攻击**即推/拉，力不在技能 blackboard 里：
+
+- **`pusher`（推击手）**：阿消 · 见行者 · 食铁兽 · 温蒂
+- **`hookmaster`（钩索师）**：暗索 · 歌蕾蒂娅 · 杏仁 · 雪雉 · 崖心
+
+其余靠技能/天赋推拉的还有：Misery、灰烬、黑键、燧石、溯光星源、可颂、焰狐龙梓兰、傀影、莱伊、罗宾、圣聆初雪、
+琳琅诗怀雅、乌尔比安，以及 `勾爪` / `暴风雪` / `喷拒器` / `猎潮的骑士` / `流形` / `weedy_token` 等 token 与装置。
+
+## 4. 顺带查清的两条官方机制（尚未建模）
+
+- **撞墙弹跳**：`bounce` / `bounceease` / `m_bounceFrictionFactor` / `_bounceBBKey`，并且 **`_bounceTimesAsDamageTimes`
+  —— 弹跳次数计入伤害次数**（温蒂 / 推击手那类撞墙伤害的官方口径）。
+- **失衡保护**：`unbalanceProtectDueTime` —— 连续推拉之间有保护窗口。
+
+## 5. 客户端的做法（本次实现）
+
+`render/units.js`：模拟位移是**瞬时**的（`sim/battle/displacement.js` 在一次调用里走完 0.1 格步进），快照只带终点，
+所以客户端补上中间帧——`UnitView.slideTo(x, y, { friction })` 建立一次滑行，`update()` **逐帧做速度积分**
+（`v ← max(0, v − a·dt)`、`d ← d + v·dt`），终点由模拟给出（**权威**），`v0 = 2D/T`、`a = v0/T` 保证
+`T` 秒内正好走完 `D` 且速度归零 —— 即官方"冲量 + 摩擦"的等效形式；`T = 0.14·√D`（夹 0.12–0.45 s）是我们拟定的
+[ASSUMED]（让画面按模拟的距离到位；没有来源给出官方时长），`friction` 是**地板因子**（本模式恒为 1；将来有冰面就乘
+< 1 ⇒ 滑得更久）。`render/app.js` 在插值器开始显示「以带终点的快照结尾」的那一段时就用 `displace` fx 启动滑行：
+到达那张快照之前画面停在原处，之后从原处减速滑入模拟的实时位置（终点，以及敌人随后继续走的路），落地不跳。
+**模拟层、协议、golden 一律未改。**
+
+滑行途中死亡：滑行照常走完，尸体停在被推到的位置（模拟里它已经在那里；0.2.2 合入时改掉了原 PR 的「回到出发格」）；
+倒地的单位交给 `setDown` 放到它的格子上。
+
+## 6. 复核方式
+
+1. 元数据：`node` 读 `global-metadata.dat`，搜上列标识符（本文件所有类名/字段名都是这样得到的）。
+2. 力度表：`zh_CN/gamedata/excel/skill_table.json` → 各技能的 `levels[].blackboard` 里 `key === 'force'`；
+   敌人侧 `levels/enemydata/enemy_database.json`。
+3. 职业：`excel/character_table.json` 的 `subProfessionId ∈ {pusher, hookmaster}`。
+4. 地板：`docs/research/05-maps.json` 的格子字符统计（本文件 §2）。
+
+## 7. 附：官方 AB 资源包的读取要点（踩过的坑）
+
+供以后要读官方战斗配置时参考（本次为定位"摩擦是不是数据"而打通）：
+
+- `Flags` 里的 `0x200`（`UsesAssetBundleEncryption`）在本客户端上是**虚设**：blocksInfo 既没有 70 字节加密前导，
+  也不需要任何 16 字节 key（暴力扫 `global-metadata.dat` 144 万候选、`GameAssembly.dll` 5 万候选均无命中即因此）。
+- blocksInfo 位置 = `align16(headerEnd)`；**块数据是连续存储**的（不要逐块对齐）。
+- 压缩：`comp 3` = 普通 LZ4 ✓；`comp 4 / 5` = Arknights 自定义 LZ4AK（nibble 交换后按 LZ4 解，
+  终止条件是 `op === uncompressedSize`，**严格相等**）。
+- 包内官方配置是**带 `$type` 的 JSON**（如 `Torappu.Battle.Action.Nodes+SetBodyDirection`），
+  内嵌类型树 ⇒ 字段名可直接读；但**摩擦不在其中**（本文档 §2 已说明原因）。
diff --git a/docs/research/14-death-animations.md b/docs/research/14-death-animations.md
new file mode 100644
index 00000000..a6c8ecf8
--- /dev/null
+++ b/docs/research/14-death-animations.md
@@ -0,0 +1,109 @@
+# 14 · Enemy death animations: the art never drops the body, and 25 clips were being cut short
+
+A player report — "a dying 帝国炮火先兆者 seems to drop at the very end", then "what about the other enemies'
+animations?" — answered by reading the client's own data and its code.
+
+## 0. TL;DR
+
+- **No enemy animation moves the whole body.** Playing all 251 enemies' clips and sampling every bone's world position,
+  the **root bone's vertical displacement is 0.000 tiles in every Die (234), Idle (235), Move (234) and Attack (215)
+  clip**. Limbs move (up to 2.16 tiles for “帝国的甲胄”'s arms); the body never does. Every vertical placement is the
+  renderer's: the fly lift, the model's own art hang (`.skel bounds.y`) and nothing else.
+- **A dying flyer dropped at the wrong moment.** The client removes its fly offset in `CharacterAnimator.OnFinish` —
+  when the finish state ends, not when the unit dies — so a drone stays aloft through the death animation and drops as
+  it goes. The remake dropped it the instant `alive` went false, so the death clip played on the ground. Fixed: the lift
+  is held for the Die clip and released inside the fade tail (§4).
+- **25 death clips were cut short by a 1.6 s cap** — 盐风主教昆图斯's 7.97 s clip played 20 % of itself, 鼠王 37 %,
+  杰斯顿·威廉姆斯 40 %, and 22 more (§3). The cap is now 8 s, above every clip in the data.
+- 17 manifest entries have no Die clip at all; they are the ground items/collectibles (§5).
+
+## 1. How the clips were read [DATA]
+
+A sweep script of the PR author (PR #380, not in this repository) reads `data/assets.json` + the extracted `.skel` files
+and **plays** each clip: `Skeleton` + `AnimationState`, stepped at 30 Hz, `state.apply(skeleton)` and
+`skeleton.updateWorldTransform()` after every step, recording the range of `skeleton.y` (the root) and of every
+`bone.worldY`. Ranges are converted to tiles with the model's `modelScale` (320 skeleton units = one tile at scale 1 —
+the conversion the flying-visuals write-up uses for the same models).
+
+Do **not** try to read the timelines directly: in this build of `@pixi-spine/runtime-3.8` they hold packed numeric
+arrays (`timeline.frames[0]` is a number, not `{time, x, y}`), so a keyframe walk silently reports zero motion — the
+first attempt here did, and 270 Attack clips "had no rotation". Sampling the played skeleton is layout-agnostic and
+matches what the client draws.
+
+## 2. Nothing translates the body [DATA]
+
+| clip | read | root displacement > 0.01 tiles |
+|---|---|---|
+| Die | 234 | **0** |
+| Idle / Default | 235 | **0** |
+| Move / Walk | 234 | **0** |
+| Attack | 215 | **0** |
+
+The largest single-bone travel inside a Die clip is 2.16 tiles (“帝国的甲胄”, a flailing limb), then 1.40 (节日气球),
+1.29 (“独轮车玩具”), 1.18 (业余竞演者) — normal animation, not a fall. A "the body sinks" effect can therefore only come
+from the code paths that place the model (`FLY_HOVER`, the `zTarget` ease, `lift`, and the artist's `bounds.y`).
+
+## 3. Death clip durations, and the 1.6 s cap that cut them [DATA]
+
+234 Death clips: shortest **0.50 s**, median **1.00 s**, longest **7.97 s**. `render/units.js` used
+`clamp(d / rate, 0.35, 1.6)`, so **25 clips were trimmed** (11 %), every one of them a boss or elite:
+
+| enemy | Die clip | played by the old cap |
+|---|---|---|
+| 盐风主教昆图斯 | 7.97 s | 1.60 s (20 %) |
+| 鼠王 | 4.33 s | 37 % |
+| 杰斯顿·威廉姆斯 | 4.00 s | 40 % |
+| W / 泥岩 | 3.33 s | 48 % |
+| 假想敌：胄 ×2 | 3.10 s | 52 % |
+| “巨大的丑东西” | 2.83 s | 56 % |
+| 腐败骑士 | 2.67 s | 60 % |
+| 高普尼克 ×2 / 卢西恩，“猩红血钻” / 假想敌：管 ×2 | 2.33 s | 69 % |
+| 假想敌：弦 | 2.30 s | 70 % |
+| 雪孩子 / 伊利昂的木驮兽 / 鸭爵 ×2 / 纠缠藤蔓 / 凋零骑士 | 2.00 s | 80 % |
+| 陷落雪祀 | 1.80 s | 89 % |
+| “帝国的甲胄” / 底海滑动者 / 富营养的滑动者 | 1.67 s | 96 % |
+
+The lower bound (0.35 s) trims nothing: the shortest real clip is 0.50 s. The client plays its clip out — its `OnFinish`
+fires when the finish state ends — so the cap only ever made the remake's deaths shorter than the official's.
+
+## 4. A dying flyer drops at the end of the clip, like the client [DATA]
+
+The client's fly offset is one constant (`Vector3(0, 0.35f, 0)` in `Torappu.Battle.CharacterAnimator`, applied by
+`_SetFlyMountPointOffset` / `_SetFlyHitOffset` while a unit flies and negated when it lands; the remake draws 0.35 in
+character space ≈ **1.3 tiles** as `FLY_HOVER` — the flying-visuals write-up has the full derivation). Its only direct
+caller is `OnFinish` (#62924, call site
+0x1805feb87), disassembled as `xor edx, edx; mov rcx, rbx; call _SetFlyMountPointOffset` — **arg 0**, the negation
+branch — followed by clearing `[this+0x128]` and a tail call to another cleanup. `OnFinish` has no direct `call` site of
+its own: it is a virtual lifecycle method (there is a `<>xLuaBaseProxy_OnFinish`), so the battle framework calls it
+through the vtable when the character's **finish** state ends.
+
+Since the Die clips carry no vertical motion (§2):
+
+- **Client**: the drone stays aloft for the whole death animation and drops as the finish state ends.
+- **Remake before**: `hoverTo = this.flying && this.alive ? FLY_HOVER : 0` — `die()` clears `alive` *before* the clip
+  plays, so every flyer sank to the ground inside ≈0.42 s (lerp τ = 1/6 s) and played its death clip **on the ground**.
+- **Remake now**: the hover target is `this.alive || (this.dying > DIE_FADE_TAIL && !this.down)` — the flyer holds
+  `FLY_HOVER` for the whole clip (the view fades over the last `DIE_FADE_TAIL` = 0.55 s of `dying`) and drops inside
+  that fade, which is the client's `OnFinish` moment. A knocked-down (`down`) flyer still lies on the ground.
+
+All 27 flying enemies of the data have a Die clip of 0.67–1.00 s, well inside the cap, so the cap change never touches
+them; 帝国炮火先兆者 and 帝国炮火中枢先兆者 are unexceptional (Die 1.00 s, root displacement 0.000).
+
+## 5. The 17 entries with no Die clip [DATA]
+
+未装配刀片 · 防护背心 · 冲击式施术单元 (deployable equipment) and 木制瑞印 · 红木瑞印 · 小说卷轴 · 诗画卷轴 · 青铜镜 ·
+黄铜镜 · 木制镇纸 · 红木镇纸 · 青瓷茶器 · 彩瓷茶器 · 铜矛头 · 铁矛头 · 铜灯盘 · 铁灯盘 (the collectible/relic props). They take
+the documented frozen-first-idle-frame path (see the `die()` comment in `render/spine.js`), which is right for an item
+that is picked up rather than killed.
+
+## 6. Implementation (2026-10-06, client-only)
+
+- `public/js/render/units.js`: new `DIE_FADE_TAIL = 0.55` (the fade tail `die()` already appended as a literal) and
+  `DIE_CLIP_MAX = 8`; `dying = clamp(d / rate, 0.35, DIE_CLIP_MAX) + DIE_FADE_TAIL`; the hover target as in §4; the three
+  `0.55` literals in `die()` / the knockdown branch / the fade now use `DIE_FADE_TAIL`.
+- `test/render/unitview.test.js`: a dying flyer keeps `FLY_HOVER` through the Die clip and is under a quarter of it
+  inside the fade (a walker stays at 0); a data guard — no enemy Die clip of `data/assets.json` exceeds `DIE_CLIP_MAX`
+  (234 clips, the longest 7.97 s: the §3 durations re-checked from the manifest when this was merged in 0.2.2) — and
+  the 7.97 s clip is scheduled whole, the view still on screen 5 s in.
+- The root-displacement sweep of §2 is the PR author's measurement (their script is not in the repository).
+- Client-only: the server serves `units.js` per request, so a hard refresh (Ctrl+F5) applies it — no restart.
diff --git a/public/js/render/app.js b/public/js/render/app.js
index 32784604..40b505a7 100644
--- a/public/js/render/app.js
+++ b/public/js/render/app.js
@@ -1412,6 +1412,14 @@ export async function createFieldView(host, options = {}) {
           consumedIds.add(e[4].id);
           if (consumedIds.size > 200) consumedIds.delete(consumedIds.values().next().value);
         }
+        // 推拉: a push / pull (battle/displacement.js) moves the enemy inside one call; its `displace` fx carries the
+        // destination ['fx', 'displace', x, y, { id }] and the view slides there (UnitView.slideTo, PR #380) — normally
+        // started already by syncBattle's look-ahead, which this repeats harmlessly
+        if (e[1] === 'displace') {
+          const d = e[4] && typeof e[4] === 'object' ? e[4] : null;
+          const v = d && d.id != null ? views.get(d.id) : null;
+          if (v && v.slideTo) v.slideTo(Number(e[2]), Number(e[3]));
+        }
         // an enemy's mode change — the `form` of a sim setForm fx (shared/protocol.js fxForm: 掠海漂移体 → 爬行模式, user
         // playtest #5 item 1; 转译基底's forms, a 逐火 ember and its revival, the leaders' 重生, 守墓石像 — user report after
         // 0.1.0) — switches the view's clip set (UnitView.setForm; a kind without a clip set of that skeleton changes
@@ -1464,10 +1472,24 @@ export async function createFieldView(host, options = {}) {
     if (best) { tiles.flashObjective(best[0], best[1]); board3d?.flashObjective(best[0], best[1]); }
   }
 
+  /** syncBattle's look-ahead: a queued `displace` fx ['fx', 'displace', x, y, { id }] starts that view's slide. */
+  let slideAt = 0;
+  function startSlide(e) {
+    if (!Array.isArray(e) || e[0] !== 'fx' || e[1] !== 'displace') return;
+    const extra = e[4] && typeof e[4] === 'object' ? e[4] : null;
+    const v = extra && extra.id != null ? views.get(extra.id) : null;
+    if (v && v.slideTo) v.slideTo(Number(e[2]), Number(e[3]), { at: slideAt });
+  }
   let renderT0Battle = null;   // game time of the first rendered battle frame (spawn puffs skip the initial wave)
   let downSeq = 0;             // syncBattle pass counter: a view still marked down after a pass left the `down` list
   function syncBattle(renderT) {
     if (renderT0Battle == null) renderT0Battle = renderT;
+    // A push / pull's slide starts as soon as the interval sampled below ends on the snapshot that carries the
+    // destination: its `displace` fx is due only when renderT reaches that snapshot, and by then sample() has already
+    // lerped (≤ teleport) or snapped the enemy most of the way — no frames in between (PR #380). The fx are still queued
+    // here (processEvents took only those ≤ renderT); the view holds until `at`, then eases into the sim's position.
+    slideAt = interp.nextSnapT(renderT);
+    if (slideAt > renderT) interp.forEachUpcoming(renderT, slideAt, startSlide);
     interp.sample(renderT, sample);
     for (const [id, s] of sample) {
       let v = views.get(id);
diff --git a/public/js/render/interp.js b/public/js/render/interp.js
index 1df0d9de..608fdbf9 100644
--- a/public/js/render/interp.js
+++ b/public/js/render/interp.js
@@ -283,6 +283,16 @@ export class SnapshotBuffer {
     return ans;
   }
 
+  /**
+   * Game time of the first snapshot after `time` (default renderT) — the newer end of the interval sample() interpolates
+   * — or NaN when there is none (extrapolating). render/app.js starts a push's slide while that interval is shown.
+   */
+  nextSnapT(time = this.renderT) {
+    const s = this.snaps;
+    const i = this._indexAt(time) + 1;
+    return Number.isFinite(time) && i < s.length ? s[i].t : NaN;
+  }
+
   /**
    * The `down` list (knocked-out operators waiting to redeploy, see header) of the snapshot shown at `time` (default
    * renderT) — the same snapshot sample() reads flags from — or null.
diff --git a/public/js/render/units.js b/public/js/render/units.js
index 4e38aaf7..a7de69ad 100644
--- a/public/js/render/units.js
+++ b/public/js/render/units.js
@@ -161,6 +161,36 @@ const RAISED_Z = 0.12;
  * ride the body (`hover`); range highlights are tiles.
  */
 export const FLY_HOVER = 1.3;
+/**
+ * A push / pull slide (推拉, PR #380 by @xcdoge): real seconds per √tile of travel. The sim displaces at once —
+ * server/sim/battle/displacement.js walks its 0.1-tile steps inside one call — so the snapshots only ever show the
+ * destination, and a pushed / pulled enemy appeared at the end of its path (a ≤ 2.5-tile push in one snapshot interval,
+ * a longer pull snapped). The view now slides there under a constant deceleration (UnitView.slideTo): the official
+ * knockback abilities (`Knockback`, `KnockBackWithDirection`, `DragTowardSource` in the client's metadata) carry an
+ * impulse (`m_force`) and a velocity decaying under friction (`m_friction`, the tile's `additionalFriction`), and the data
+ * has no per-skill duration (docs/research/13-knockback-official.md). The duration T = DISPLACE_SLIDE·√D, kept in
+ * 0.12–0.45 s, is ours [ASSUMED: a fit so the view arrives where the sim put it — no source gives the official
+ * timing]; v0 = 2D/T, a = v0/T then run the distance in exactly T. Purely visual: the sim's timing, damage, blocking and
+ * the golden digests are untouched.
+ */
+export const DISPLACE_SLIDE = 0.14;
+/**
+ * Terrain friction factor of a slide: 1 = normal land, < 1 = slippery (ICE_LAND) slides longer. Every tile of this mode
+ * is normal land (its 11 maps have no ice or slime), so it is always 1.
+ */
+export const SLIDE_FRICTION = 1;
+/**
+ * Seconds of the death fade that follows the Die clip in `dying` (die(): the clip, then this tail). A flying unit keeps
+ * its lift for the whole clip and drops only inside this tail (PR #380: the official client removes its fly offset in
+ * `CharacterAnimator.OnFinish`, when the finish state ends — docs/research/14-death-animations.md).
+ */
+const DIE_FADE_TAIL = 0.55;
+/**
+ * Longest Die clip a death plays out (s): the longest enemy Die clip of data/assets.json is 盐风主教昆图斯's 7.97 s (234
+ * enemy Die clips; the old 1.6 s cap cut 25 of them short — the bosses' most), and the official client plays its clip
+ * out (PR #380). It only bounds a view whose data lies.
+ */
+export const DIE_CLIP_MAX = 8;
 
 /** b.snap `down` entry states (server/sim/constants.js DOWN_STATE). */
 export const DOWN_STATE = Object.freeze({ COUNTING: 0, WAIT_DP: 1, WAIT_TILE: 2 });
@@ -393,6 +423,7 @@ export class UnitView {
     this.tier = clamp(Number(info.tier) || 1, 1, 6);
     this.x = Number(info.x) || 0; this.y = Number(info.y) || 0; this.z = 0;
     this.zTarget = null;          // battle: standing height the feet ease towards (tile top under the unit; 0 for enemies)
+    this.slide = null;            // a push / pull slide (slideTo): held, then easing into the sim's position (update)
     /** @type {number|null} */
     this.shadowZ = null;          // an enemy flyer's shadow height (the tile top under it), else null: the shadow is at z
     /** @type {number|null} */
@@ -726,13 +757,18 @@ export class UnitView {
     // the element gauge shown (b.snap `elem`): element, fill 0..1, cooldown end (game s) and length
     this.el = typeof s.el === 'string' ? s.el : null;
     this.elFill = this.el ? s.elFill || 0 : 0; this.elUntil = this.el ? s.elUntil || 0 : 0; this.elDur = this.el ? s.elDur || 0 : 0;
-    this.x = s.x; this.y = s.y;
+    // a push / pull slide owns the drawn position (slideTo): the sample only anchors where it eases to, from the
+    // snapshot that carries the destination on (`at`) — before that the sample is still sliding or snapping there
+    const sl = this.slide;
+    if (!sl) { this.x = s.x; this.y = s.y; }
+    else if (!(t < sl.at)) { sl.lx = s.x; sl.ly = s.y; sl.live = true; }
     this.flying = !!(s.flags & UF.FLYING) || this.info.motion === 'FLY';
     // enemies keep to the road plane: ground enemies only ever walk low tiles (a rounding step onto a block edge must not
     // pop them up), and a flyer hovers FLY_HOVER above the road whatever tile it crosses — the official lift is one
     // constant over the route (docs/research/12), so a block under it is no step (GitHub #277: a flyer passing over one
     // high-ground / forbidden block rose and dropped like stairs). Its shadow still lies on the tile top under it.
-    const floor = groundZ(this.ctx, s.x, s.y);
+    // While sliding, the floor is read under the view's own (mid-flight) position, not the destination's.
+    const floor = this.slide ? groundZ(this.ctx, this.x, this.y) : groundZ(this.ctx, s.x, s.y);
     const gz = this.isEnemy ? 0 : floor;
     if (this.zTarget == null) this.z = gz;
     this.zTarget = gz;
@@ -755,6 +791,39 @@ export class UnitView {
 
   setWorld(x, y, z = 0) { this.x = x; this.y = y; this.z = z; }
 
+  /**
+   * Slide to a displacement's destination (推拉, the `displace` fx at (x, y)) instead of appearing there (DISPLACE_SLIDE).
+   * `at` (game s): the time of the snapshot that carries the destination — render/app.js starts the slide as soon as the
+   * interpolator shows the interval before it, and until the render clock reaches `at` the view holds where it stood
+   * (the sample in between is a lerp or a snap towards the destination). From then on it eases from there into the
+   * sampled position — the destination, and the walk the enemy resumes from it —, so it lands without a jump. Without
+   * `at` the destination counts as shown. A unit that dies on the way finishes the slide: its body lies where the push
+   * put it (the sim's position); a dead one is placed there, a knocked-down one is left to setDown.
+   */
+  slideTo(x, y, opts = {}) {
+    if (!Number.isFinite(x) || !Number.isFinite(y)) return;
+    // already on the way there: app.js starts the slide ahead of the event, then the event itself asks again
+    if (this.slide && this.slide.x1 === x && this.slide.y1 === y) return;
+    if (this.down) { this.slide = null; return; }
+    const dx = x - this.x, dy = y - this.y;
+    const D = Math.hypot(dx, dy);
+    if (!this.alive || !(D > 0.05)) { this.x = x; this.y = y; this.slide = null; return; }
+    const f = Number.isFinite(opts.friction) && opts.friction > 0 ? opts.friction : SLIDE_FRICTION;
+    // a slippery tile (f < 1) slides longer; the duration still follows √D (constant deceleration)
+    const T = Math.max(0.05, (opts.dur > 0 ? opts.dur : clamp(DISPLACE_SLIDE * Math.sqrt(D), 0.12, 0.45)) / f);
+    // v0 = 2D/T and a = v0/T run the distance in exactly T with the velocity reaching 0 there, integrated in update().
+    // The official turns a displaced unit towards the force (its _dontChangeFaceByDirection is an opt-in flag), while
+    // our facing comes from the snapshot's vx — which points back down the route the enemy resumes after the
+    // displacement, i.e. against the push. The slide therefore owns the facing until it lands.
+    if (this.isEnemy) this.visFacing = dx < 0 ? -1 : 1;
+    const v0 = 2 * D / T;
+    const at = Number.isFinite(opts.at) ? opts.at : -Infinity;
+    this.slide = {
+      x1: x, y1: y, sx: this.x, sy: this.y, ux: dx / D, uy: dy / D, D, done: 0, v: v0, a: v0 / T, t: 0, dur: T,
+      at, live: at === -Infinity, lx: x, ly: y, ox: 0, oy: 0, run: false, wait: 0,
+    };
+  }
+
   setFacing(f) {
     if (this.isEnemy) { this.facing = f === -1 ? -1 : 1; return; }
     // the legacy ±1 only speaks about left / right: an UP / DOWN operator keeps its direction
@@ -909,7 +978,7 @@ export class UnitView {
     if (this.actor && !d) d = this._fallDur();
     const rate = this.ctx.animRate?.() || 1;
     this.dieT = 0;
-    this.dying = clamp(d / rate, 0.35, 1.6) + 0.55;
+    this.dying = clamp(d / rate, 0.35, DIE_CLIP_MAX) + DIE_FADE_TAIL;
     this.dieDur = this.dying;
     if (instant) { this.dieT = 30; if (this.actor) this.actor.update(30); }
   }
@@ -948,7 +1017,7 @@ export class UnitView {
     if (!d) {
       if (!this.down) return;
       this.down = null;
-      if (!this.alive) { this.dying = 0.55; this.dieDur = 0.55; }
+      if (!this.alive) { this.dying = DIE_FADE_TAIL; this.dieDur = DIE_FADE_TAIL; }
       return;
     }
     if (this.alive) this.die(instant);
@@ -969,6 +1038,31 @@ export class UnitView {
   /** @param {number} dt real seconds @param {any} cam camera @param {number} t real clock */
   update(dt, cam, t) {
     if (this.destroyed) return;
+    // a displacement's slide (slideTo): held where it stood until the snapshot with the destination is shown, then
+    // eased into the sampled position (sync keeps `lx, ly` current) under a constant deceleration
+    if (this.slide) {
+      const sl = this.slide;
+      if (this.down) this.slide = null;   // a knocked-down view lies on its tile (setDown)
+      else if (!sl.live) {
+        this.x = sl.sx; this.y = sl.sy;
+        // never shown (the unit left the snapshots, a stalled stream): the snapshot takes the view back
+        if ((sl.wait += dt) > 0.5) this.slide = null;
+      } else {
+        if (!sl.run) { sl.run = true; sl.ox = sl.sx - sl.lx; sl.oy = sl.sy - sl.ly; }
+        const step = Math.min(dt, 0.1);                // a hidden tab's catch-up frame must not overshoot
+        const v0 = sl.v;
+        sl.v = Math.max(0, sl.v - sl.a * step);        // friction: the velocity decays every frame
+        // the step's mean velocity — exact under a constant deceleration (the end-of-step speed fell ~D·dt/T short:
+        // 9 % of a 0.18 s slide at 60 fps, then a jump onto the end)
+        sl.done = Math.min(sl.D, sl.done + (v0 + sl.v) / 2 * step);
+        sl.t += step;
+        if (this.isEnemy) this.visFacing = sl.ux < 0 ? -1 : 1;
+        const k = 1 - sl.done / sl.D;                  // the share of the way still to go
+        this.x = sl.lx + sl.ox * k; this.y = sl.ly + sl.oy * k;
+        // the clock or the spent velocity lands it on the sampled position
+        if (sl.t >= sl.dur - 1e-9 || sl.done >= sl.D - 1e-9 || sl.v <= 1e-9) { this.x = sl.lx; this.y = sl.ly; this.slide = null; }
+      }
+    }
     const P = this.P;
     // the model for the state the frame's events and snapshot left (Front ⇄ Back when it went down / stood up: die, revive)
     if (this._modelDirty) { this._modelDirty = false; this._syncModel(); }
@@ -987,7 +1081,9 @@ export class UnitView {
       const d = this.shadowZTarget - this.shadowZ;
       this.shadowZ = Math.abs(d) < 1e-3 ? this.shadowZTarget : this.shadowZ + d * Math.min(1, dt * 12);
     }
-    const hoverTo = this.flying && this.alive ? FLY_HOVER : 0;
+    // a flyer keeps its lift through the Die clip and drops only as it fades out: the client removes the fly offset in
+    // CharacterAnimator.OnFinish, when the finish state ends; a knocked-down flyer lies on the ground
+    const hoverTo = this.flying && (this.alive || (this.dying > DIE_FADE_TAIL && !this.down)) ? FLY_HOVER : 0;
     if (this.hover !== hoverTo) this.hover = Math.abs(hoverTo - this.hover) < 1e-3 ? hoverTo : this.hover + (hoverTo - this.hover) * Math.min(1, dt * 6);
     const p = cam.project(this.x, this.y, this.z + this.hover + this.lift, this.screen);
     const s = p.s;
@@ -1001,7 +1097,7 @@ export class UnitView {
     } else if (this.dying > 0) {
       this.dieT += dt;
       this.dying -= dt;
-      const tail = 0.55;
+      const tail = DIE_FADE_TAIL;
       if (this.dying < tail) alpha *= Math.max(0, this.dying / tail);
       if (this.dying <= 0) { this.dying = 0; this.remove = true; alpha = 0; }
     }
diff --git a/test/render/unitview.test.js b/test/render/unitview.test.js
index 26e426b9..1e033118 100644
--- a/test/render/unitview.test.js
+++ b/test/render/unitview.test.js
@@ -435,3 +435,277 @@ describe('a fast enemy walks on its Run cycle (PR #275)', () => {
     assert.equal(hound.actor.roles.skill.loop, 'Skill_02', 'the cast slot survives that too');
   });
 });
+
+// 推拉 (player report): the sim displaces instantly (battle/displacement.js walks 0.1-tile steps inside one call) and the
+// snapshot only carries the destination, so the view eases there (app.js `displace` fx → UnitView.slideTo) instead of
+// appearing at the end of the path.
+describe('a push / pull slide (推拉: the official impulse under friction)', () => {
+  const view = async (id = 1) => {
+    const ctx = fakeViewCtx(fake.P, { assets: store({ spine: true }), cam });
+    const v = new UnitView(ctx, { id, side: 'enemy', kind: 'enemy', defId: 'enemy_1007_slime', x: 5, y: 12, maxHp: 100 }, {});
+    await tick(); await tick();
+    return v;
+  };
+  // 推进 n 帧（update 会把单帧 dt 截到 0.1 s，所以必须多帧走完）
+  const step = (v, dur, n = 60) => { for (let i = 0; i < n; i++) v.update(dur / n, cam(), 0); };
+
+  test('slideTo runs a real deceleration: the velocity falls every frame and stops on the destination', async () => {
+    const v = await view();
+    v.slideTo(7.7, 12);
+    const sl = v.slide;
+    assert.ok(sl, 'a slide is in flight');
+    assert.ok(sl.v > 0 && sl.a > 0, 'it starts with a speed and a deceleration');
+    assert.ok(Math.abs(sl.v * sl.v / (2 * sl.a) - 2.7) < 1e-6, 'v²/2a = the distance (constant deceleration)');
+    let prev = sl.v;
+    let monotone = true;
+    for (let i = 0; i < 40; i++) {
+      v.update(sl.dur / 80, cam(), 0);
+      if (v.slide && v.slide.v > prev + 1e-9) monotone = false;
+      if (!v.slide) break;
+      prev = v.slide.v;
+    }
+    assert.ok(monotone, 'the velocity only ever decreases');
+    step(v, sl.dur);
+    assert.equal(v.x, 7.7, 'it arrives exactly on the authoritative destination');
+    assert.equal(v.y, 12, 'the cross axis holds');
+    assert.equal(v.slide, null);
+  });
+
+  test('starting a slide from the destination is a no-op (why app.js pre-scans the frame)', async () => {
+    // The trap this guards: app.js's snapshot loop runs before processEvents, and the snapshot already carries the
+    // displacement's destination, so a fx handler that runs after it finds the view there and has nothing to animate —
+    // the reported pause with no frames. app.js therefore starts the slide from the pre-snapshot position.
+    const v = await view(8);
+    v.sync({ x: 7.7, y: 12, hp: 100, maxHp: 100, sp: 0, spMax: 0, flags: 0, anim: 0 });
+    assert.equal(v.x, 7.7);
+    v.slideTo(7.7, 12);
+    assert.equal(v.slide, null, 'no slide when the view is already there');
+  });
+
+  test('a second request for the same destination never restarts the slide in flight', async () => {
+    const v = await view(9);
+    v.slideTo(7.7, 12);
+    const first = v.slide;
+    for (let i = 0; i < 10; i++) v.update(first.dur / 40, cam(), 0);
+    const mid = v.x, done = v.slide.done;
+    v.slideTo(7.7, 12);                       // the fx handler, later in the same frame
+    assert.equal(v.slide, first, 'the same slide object, not a restart');
+    assert.equal(v.x, mid, 'the position is untouched');
+    assert.equal(v.slide.done, done);
+    step(v, first.dur);
+    assert.equal(v.x, 7.7, 'and it still lands');
+  });
+
+  test('a pushed enemy faces the way it is pushed, not the route it resumes', async () => {
+    // The official turns a displaced unit towards the force (_dontChangeFaceByDirection is an opt-in flag); our facing
+    // comes from the snapshot's vx, which after a displacement points back down the route the enemy walks again —
+    // i.e. against the push (player report: 被推开敌人的方向反过来了).
+    const v = await view(10);
+    v.sync({ x: 5, y: 12, hp: 100, maxHp: 100, sp: 0, spMax: 0, flags: 0, anim: 0, vx: -1.2 });
+    assert.equal(v.visFacing, -1, 'walking left before the push');
+    v.slideTo(7.7, 12);                       // pushed to the right
+    assert.equal(v.visFacing, 1, 'faces the push at once');
+    for (let i = 0; i < 20; i++) v.update(v.slide.dur / 40, cam(), 0);
+    assert.equal(v.visFacing, 1, 'still facing the push in flight');
+    v.slideTo(5.2, 12);                       // now pulled back to the left
+    assert.equal(v.visFacing, -1, 'and the other way for a pull');
+  });
+
+  test('a snapshot in flight does not teleport it (the slide owns the position until it lands)', async () => {
+    const v = await view(7);
+    v.slideTo(7.7, 12);
+    const dur = v.slide.dur;
+    for (let i = 0; i < 12; i++) v.update(dur / 40, cam(), 0);
+    const mid = v.x;
+    assert.ok(mid > 5.2 && mid < 7.6, `mid-flight (${mid})`);
+    // the sim's snapshots already carry the destination (it displaced the enemy inside one call), so a plain sync
+    // would snap the view there — the reported "no frames in between"
+    v.sync({ x: 7.7, y: 12, hp: 100, maxHp: 100, sp: 0, spMax: 0, flags: 0, anim: 0 });
+    assert.equal(v.x, mid, 'the snapshot does not move a sliding view');
+    assert.equal(v.y, 12);
+    step(v, dur);
+    assert.equal(v.x, 7.7, 'and it still lands on the destination');
+    // once landed, snapshots drive it again
+    v.update(dur, cam(), 0);
+    v.sync({ x: 6.4, y: 12, hp: 100, maxHp: 100, sp: 0, spMax: 0, flags: 0, anim: 0 });
+    assert.equal(v.x, 6.4, 'a landed view follows the snapshot again');
+  });
+
+  test('a slippery floor (a smaller friction factor) slides longer and lands just the same', async () => {
+    const dry = await view(2), ice = await view(3);
+    dry.slideTo(7.7, 12);
+    ice.slideTo(7.7, 12, { friction: 0.5 });
+    assert.ok(ice.slide.dur > dry.slide.dur * 1.5, `ice ${ice.slide.dur} > dry ${dry.slide.dur}`);
+    step(ice, ice.slide.dur * 1.05, 90);
+    assert.equal(ice.x, 7.7, 'the destination is authoritative whatever the floor');
+  });
+
+  test('the duration follows √distance, not distance', async () => {
+    const near = await view(4), far = await view(5);
+    near.slideTo(6.2, 12); far.slideTo(10.5, 12);          // 1.2 vs 5.5 tiles
+    assert.ok(far.slide.dur > near.slide.dur, `${far.slide.dur} > ${near.slide.dur}`);
+    assert.ok(far.slide.dur / near.slide.dur < 2.6, 'sub-linear (∝ √d)');
+  });
+
+  test('a trivial move snaps, an unknown target is ignored; a unit that dies on the way lies where it was pushed', async () => {
+    const v = await view(6);
+    v.slideTo(5.01, 12);
+    assert.equal(v.slide, null); assert.equal(v.x, 5.01, 'a sub-0.05 tile move is not a displacement');
+    v.slideTo(NaN, 12);
+    assert.equal(v.slide, null); assert.equal(v.x, 5.01);
+    v.slideTo(7.7, 12);
+    step(v, v.slide.dur / 3, 20);
+    assert.ok(v.x > 5 && v.x < 7.7, `moving (${v.x})`);
+    // the sim's displacement already put the body at the destination (a Weedy wall kill dies there): the corpse
+    // finishes the slide and stays — PR #380 sent it back to where it stood, and the next snapshot then jumped it
+    v.die();
+    v.update(1, cam(), 0);
+    v.update(0.1, cam(), 0);
+    assert.equal(v.x, 7.7, 'the corpse lies where the push put it');
+    assert.equal(v.slide, null);
+    const dead = await view(11);
+    dead.die();
+    dead.slideTo(7.7, 12);
+    assert.equal(dead.slide, null, 'a dead view does not start a slide');
+    assert.equal(dead.x, 7.7, 'it is placed on the destination');
+  });
+
+  test('held until the snapshot with the destination is shown (`at`), then eased into the sampled position — the walk it resumes included — with no jump on landing', async () => {
+    const v = await view(12);
+    v.sync({ x: 5, y: 12, hp: 100, maxHp: 100, sp: 0, spMax: 0, flags: 0, anim: 1, vx: -0.8 }, 2.9);
+    v.slideTo(7.7, 12, { at: 3 });              // app.js: the interval ending on the destination's snapshot is shown
+    for (const [x, t] of [[5.9, 2.93], [6.8, 2.96]]) {   // the interpolator lerps there in the meantime
+      v.sync({ x, y: 12, hp: 100, maxHp: 100, sp: 0, spMax: 0, flags: 0, anim: 1, vx: 27 }, t);
+      v.update(1 / 60, cam(), 0);
+      assert.equal(v.x, 5, `held where it stood at ${t}`);
+    }
+    // from the destination's snapshot on the sample anchors the slide, and the enemy walks back down its route
+    let live = 7.7, prev = v.x, maxStep = 0, frames = 0;
+    for (let t = 3; v.slide && frames < 120; t += 1 / 30, frames++) {
+      v.sync({ x: live, y: 12, hp: 100, maxHp: 100, sp: 0, spMax: 0, flags: 0, anim: 1, vx: -0.8 }, t);
+      v.update(1 / 60, cam(), 0);
+      maxStep = Math.max(maxStep, Math.abs(v.x - prev)); prev = v.x;
+      live -= 0.8 / 30;
+    }
+    assert.ok(frames >= 8, `a slide of ${frames} frames, not a jump`);
+    assert.equal(v.slide, null);
+    assert.ok(maxStep < 0.4, `no frame moves more than ${maxStep.toFixed(3)} tiles`);
+    const landed = v.x;
+    v.sync({ x: live, y: 12, hp: 100, maxHp: 100, sp: 0, spMax: 0, flags: 0, anim: 1, vx: -0.8 }, 3 + frames / 30);
+    assert.ok(Math.abs(v.x - landed) < 0.05, `landed on the walking enemy (${landed.toFixed(3)} → ${v.x.toFixed(3)})`);
+  });
+
+  test('a slide that is never shown (the unit left the snapshots) hands the view back', async () => {
+    const v = await view(13);
+    v.slideTo(7.7, 12, { at: 3 });
+    for (let i = 0; i < 40; i++) v.update(1 / 60, cam(), 0);
+    assert.equal(v.slide, null);
+    v.sync({ x: 6.1, y: 12, hp: 100, maxHp: 100, sp: 0, spMax: 0, flags: 0, anim: 1 }, 3.4);
+    assert.equal(v.x, 6.1);
+  });
+});
+
+// the app.js frame order (render/app.js: processEvents takes the events ≤ renderT, then syncBattle's look-ahead starts a
+// slide for a `displace` fx still queued up to the next snapshot, then sample → sync, then update) run over a real
+// battle: a pushed enemy is drawn sliding, not snapped
+describe('a push through SnapshotBuffer and UnitView in the app.js frame order (PR #380)', () => {
+  async function pushed({ kill = false } = {}) {
+    const { makeBattle, enemyRec } = await import('../helpers/battleHarness.js');
+    const { SnapshotBuffer } = await import('../../public/js/render/interp.js');
+    const { snapFrame } = await import('../../server/match/fields.js');
+    const h = makeBattle({ defs: { enemies: { enemy_walker: enemyRec({ key: 'enemy_walker', hp: 1e6, speed: 0.8 }) } },
+      enemies: [{ key: 'enemy_walker', time: 0, route: 0 }], content: 'none', autoFinish: false, timeLimit: 60 });
+    const frames = [];
+    let e = null, info = null, moved = 0, dest = null;
+    for (let i = 0; i < 30 * 6; i++) {
+      h.step();
+      e = e || h.enemy('enemy_walker');
+      if (!moved && h.b.time >= 3) {
+        moved = h.b.displace(e, { x: 1, y: 0 }, 1.7);
+        dest = e.x;
+        if (kill) h.b.kill(e, null);
+      }
+      if (i % 3 === 2) {
+        const ev = h.b.drainEvents();
+        info = info || ev.find((x) => x[0] === 'spawn')?.[1];
+        const s = h.b.snapshot();
+        frames.push({ at: s.t / 2, snap: snapFrame('f', s), ev, gt: s.t });
+      }
+    }
+    assert.ok(moved > 1, `the sim pushed it ${moved} tiles`);
+    const ctx = fakeViewCtx(fake.P, { cam });
+    const v = new UnitView(ctx, { ...info, id: e.id }, {});
+    const buf = new SnapshotBuffer(), sample = new Map(), xs = [];
+    const start = (ev, at) => { if (ev[0] === 'fx' && ev[1] === 'displace' && ev[4]?.id === e.id) v.slideTo(Number(ev[2]), Number(ev[3]), at == null ? {} : { at }); };
+    for (let f = 0, fi = 0; f < 60 * 3; f++) {
+      const now = f / 60;
+      for (; fi < frames.length && frames[fi].at <= now; fi++) { buf.push(frames[fi].snap, frames[fi].at); buf.pushEvents(frames[fi].ev, frames[fi].at, frames[fi].gt); }
+      const renderT = buf.update(now);
+      if (!Number.isFinite(renderT)) continue;
+      for (const ev of buf.takeEvents(renderT, [])) { start(ev); if (ev[0] === 'die' && ev[1] === e.id && v.alive) v.die(); }
+      const at = buf.nextSnapT(renderT);
+      if (at > renderT) buf.forEachUpcoming(renderT, at, (ev) => start(ev, at));
+      buf.sample(renderT, sample);
+      if (sample.get(e.id)) v.sync(sample.get(e.id), renderT);
+      v.update(1 / 60, cam(), now);
+      if (renderT > 2.8 && renderT < 3.8) xs.push(v.x);
+    }
+    return { xs, dest };
+  }
+
+  test('a 1.7-tile push is drawn over a dozen frames, every frame a step under 0.35 tiles', async () => {
+    const { xs } = await pushed();
+    let big = 0, moving = 0;
+    for (let i = 1; i < xs.length; i++) { const d = Math.abs(xs[i] - xs[i - 1]); big = Math.max(big, d); if (d > 0.02) moving++; }
+    assert.ok(moving >= 8, `${moving} frames show it moving (the bare interpolator: 3)`);
+    assert.ok(big < 0.35, `largest step ${big.toFixed(3)} tiles (the bare interpolator: 0.58)`);
+  });
+
+  test('killed right after the push, the body slides on to where the sim left it and stays there', async () => {
+    const { xs, dest } = await pushed({ kill: true });
+    assert.ok(Math.abs(xs[xs.length - 1] - dest) < 0.011, `${xs[xs.length - 1]} vs ${dest}`);
+    const from = xs.findIndex((x, i) => i > 0 && x > xs[i - 1] + 0.01);   // the slide's first frame (it walked left before)
+    assert.ok(from > 0);
+    for (let i = from; i < xs.length; i++) assert.ok(xs[i] >= xs[i - 1] - 1e-9, `never back towards where it stood (frame ${i})`);
+  });
+});
+
+// PR #380, death: a flyer holds its lift through the Die clip (the official client drops its fly offset in
+// CharacterAnimator.OnFinish) and a long Die clip plays whole (DIE_CLIP_MAX, data/assets.json's longest 7.97 s)
+describe('death timing (PR #380): a dying flyer drops inside the fade, a long Die clip plays whole', () => {
+  test('a dying flyer keeps FLY_HOVER through its Die clip and sinks only in the fade tail; a walker stays down', async () => {
+    const { FLY_HOVER, UF } = { ...(await import('../../public/js/render/units.js')), ...(await import('../../shared/constants.js')) };
+    const ctx = fakeViewCtx(fake.P, { cam });
+    const fly = new UnitView(ctx, { id: 21, side: 'enemy', kind: 'enemy', defId: 'enemy_fly', motion: 'FLY', x: 5, y: 12, maxHp: 100 }, {});
+    fly.sync({ x: 5, y: 12, hp: 100, maxHp: 100, sp: 0, spMax: 0, flags: UF.FLYING, anim: 1 }, 1);
+    for (let i = 0; i < 120; i++) fly.update(1 / 60, cam(), 0);
+    assert.ok(Math.abs(fly.hover - FLY_HOVER) < 1e-3, 'aloft while alive');
+    fly.die();                                   // no clip known: 0.35 s of clip, then the 0.55 s fade
+    for (let i = 0; i < 18; i++) fly.update(1 / 60, cam(), 0);
+    assert.ok(Math.abs(fly.hover - FLY_HOVER) < 1e-3, `still aloft in the Die clip (${fly.hover.toFixed(3)})`);
+    for (let i = 0; i < 30; i++) fly.update(1 / 60, cam(), 0);
+    assert.ok(fly.hover < FLY_HOVER * 0.25, `sinking in the fade (${fly.hover.toFixed(3)})`);
+    const walker = new UnitView(ctx, { id: 22, side: 'enemy', kind: 'enemy', defId: 'enemy_walk', x: 5, y: 12, maxHp: 100 }, {});
+    walker.die();
+    walker.update(1 / 60, cam(), 0);
+    assert.equal(walker.hover, 0);
+  });
+
+  test('every enemy Die clip of data/assets.json is within DIE_CLIP_MAX, and a 7.97 s one is scheduled whole', async () => {
+    const { DIE_CLIP_MAX, dieClipDur } = await import('../../public/js/render/units.js');
+    const durs = Object.values(ASSETS.enemies).map((e) => dieClipDur(e && e.spine)).filter((d) => d > 0);
+    assert.ok(durs.length > 200, `${durs.length} enemy Die clips`);
+    const longest = Math.max(...durs);
+    assert.ok(longest <= DIE_CLIP_MAX, `longest Die clip ${longest} s ≤ ${DIE_CLIP_MAX}`);
+    assert.ok(durs.filter((d) => d > 1.6).length > 0, 'the old 1.6 s cap cut some clips short');
+    const entry = { skel: '/s/q.skel', atlas: '/s/q.atlas', textures: ['/s/q.png'], anims: { idle: 'Idle', die: 'Die' }, animations: { Idle: 1, Die: longest } };
+    const assets = { ...store({ spine: true }), spineEntry: () => entry };
+    const v = new UnitView(fakeViewCtx(fake.P, { assets, cam }), { id: 23, side: 'enemy', kind: 'enemy', defId: 'enemy_1521_dslily', x: 5, y: 12, maxHp: 100 }, {});
+    await tick(); await tick();
+    assert.ok(v.actor, 'the model is up');
+    v.die();
+    assert.ok(Math.abs(v.dying - (longest + 0.55)) < 1e-6, `the whole clip, then the fade (${v.dying.toFixed(3)} s)`);
+    for (let i = 0; i < 300; i++) v.update(1 / 60, cam(), 0);
+    assert.ok(!v.remove && v.alpha > 0.5, 'still on screen 5 s in');
+  });
+});
diff --git a/test/sim/displace-fx.test.js b/test/sim/displace-fx.test.js
new file mode 100644
index 00000000..680e3743
--- /dev/null
+++ b/test/sim/displace-fx.test.js
@@ -0,0 +1,33 @@
+// The contract between server/sim/battle/displacement.js and render/app.js: a displacement puts a
+// ['fx', 'displace', x, y, { id }] tuple into the stream the client renders. The client must read the destination
+// from the tuple's own slots — e[4] carries the id only, and reading x/y from it silently produced NaN, which made
+// slideTo a no-op (player report: 有停顿但没有中间帧).
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { makeBattle, enemyRec } from '../helpers/battleHarness.js';
+
+const walker = (o = {}) => enemyRec({ key: 'enemy_walker', hp: 1e6, speed: 1, ...o });
+
+test('a displacement puts a `displace` fx into the event stream the client receives', () => {
+  const h = makeBattle({
+    defs: { enemies: { enemy_walker: walker({ speed: 0.01 }) } },
+    enemies: [{ key: 'enemy_walker', pos: [10, 6] }],
+    content: 'none', autoFinish: false,
+  });
+  h.step();
+  const e = h.enemy('enemy_walker');
+  h.b.drainEvents();                                   // clear the spawn/etc. batch
+  const moved = h.b.displace(e, { x: 1, y: 0 }, 2, { force: 1 });
+  assert.ok(moved > 1.8, 'the enemy moved: ' + moved);
+  const evs = h.b.drainEvents();
+  const fx = (evs || []).filter((t) => Array.isArray(t) && t[0] === 'fx');
+  const disp = fx.find((t) => t[1] === 'displace');
+  assert.ok(disp, 'the stream carries a displace fx: ' + JSON.stringify(fx));
+  // the fx rounds its coordinates to 2 decimals (events.js fx), the unit keeps full precision
+  assert.ok(Math.abs(disp[2] - e.x) <= 0.01, 'e[2] is the destination x: ' + disp[2] + ' vs ' + e.x);
+  assert.ok(Math.abs(disp[3] - e.y) <= 0.01, 'e[3] is the destination y: ' + disp[3] + ' vs ' + e.y);
+  assert.equal(disp[4] && disp[4].id, e.id, 'e[4].id is the displaced unit');
+  assert.equal(disp[4].x, undefined, 'e[4] carries no x — reading it gave NaN, so no slide ever ran');
+  assert.equal(disp[4].y, undefined, 'e[4] carries no y either');
+});
+

From dd23572b4a62a3f32b1f187bc9ba9cacb23e4312 Mon Sep 17 00:00:00 2001
From: sganggs <sganggs@users.noreply.github.com>
Date: Thu, 8 Oct 2026 19:10:15 +0800
Subject: [PATCH 4/7] =?UTF-8?q?feedback7=20R22-RENDER:=20=E7=90=B3?=
 =?UTF-8?q?=E7=90=85=E8=AF=97=E6=80=80=E9=9B=85's=20=E9=A6=99=E6=A7=9F?=
 =?UTF-8?q?=E7=82=B8=E5=BC=B9=20never=20shows=20an=20HP=20bar=20=E2=80=94?=
 =?UTF-8?q?=20PRTS=20=E5=A4=87=E6=B3=A8=20"=E5=8D=B3=E4=BD=BF=E8=87=AA?=
 =?UTF-8?q?=E8=BA=AB=E7=94=9F=E5=91=BD=E5=80=BC=E6=9C=AA=E6=BB=A1=EF=BC=8C?=
 =?UTF-8?q?=E6=A8=A1=E5=9E=8B=E4=B8=8B=E6=96=B9=E4=B9=9F=E4=B8=8D=E4=BC=9A?=
 =?UTF-8?q?=E6=98=BE=E7=A4=BA=E7=94=9F=E5=91=BD=E5=80=BC=E6=A7=BD"=20(owne?=
 =?UTF-8?q?r=20item=2011);=20golden:=20unchanged?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The owner reported 「琳琅诗怀雅的2技能的香槟会掉血，会被治疗」. Allies always draw an HP bar (render/units.js
_updateHud), so the bomb's every HP change showed. PRTS 香槟炸弹 (实体类型 装置, 1000 HP) says no HP bar is shown even
below full HP; nothing there makes it invulnerable or unhealable. Its bar is now hidden at any HP (NO_HP_BAR). Its HP,
the damage it takes (活性源石 hurts what stands on it — 70 true damage a second) and healing are left as they are: no
invulnerability added; whether it should be unhealable is the owner's decision (no written source says so).

Tests: test/render/champagne-hpbar.test.js (new, 2: no bar at full HP, hurt or healed; another summon keeps its bar)
2/2; render/unitview 35/35.
---
 public/js/render/units.js           |  8 +++++-
 test/render/champagne-hpbar.test.js | 43 +++++++++++++++++++++++++++++
 2 files changed, 50 insertions(+), 1 deletion(-)
 create mode 100644 test/render/champagne-hpbar.test.js

diff --git a/public/js/render/units.js b/public/js/render/units.js
index a7de69ad..206c8278 100644
--- a/public/js/render/units.js
+++ b/public/js/render/units.js
@@ -117,6 +117,12 @@ const nowMs = () => (globalThis.performance ? globalThis.performance.now() : Dat
  *  无头像; data/assets.json has no avatar or model for it, so the token fallback showed 圣聆初雪's own face) — the marker of a
  *  frozen gate. */
 const ICE_TOKENS = new Set(['token_10058_sbell2_icetgt']);
+/**
+ * Units that never show an HP bar: 琳琅诗怀雅's 香槟炸弹 — PRTS 香槟炸弹 备注 "即使自身生命值未满，模型下方也不会显示生命值槽"
+ * (the owner's report of 2026-10-08, 「香槟会掉血，会被治疗」: the bar showed every change). Only the bar: its HP, the
+ * damage it takes (活性源石 hurts what stands on it) and healing are unchanged — no source makes it invulnerable.
+ */
+const NO_HP_BAR = new Set(['token_10031_swire2_gdtrap']);
 const ICE_FRAME = 0x9fe6ff;
 /** How long a view waits for its avatar before showing the image-less placeholder diamond. */
 const PIC_WAIT_MS = 400;
@@ -1249,7 +1255,7 @@ export class UnitView {
     const prep = this.prep;
     const showBars = !prep && this.alive && this.info.kind !== 'item';
     const damaged = this.hp < this.maxHp - 0.5;
-    const showHp = showBars && (!this.isEnemy || damaged || this.isBoss);
+    const showHp = showBars && (!this.isEnemy || damaged || this.isBoss) && !NO_HP_BAR.has(this.info.defId);
     const bw = clamp(s * (this.isBoss ? UNIT.bossBarWidth : UNIT.barWidth), 24, this.isBoss ? 260 : 96);
     const bh = clamp(s * (this.isBoss ? 0.12 : 0.075), 3, this.isBoss ? 12 : 7);
     // a knocked-down operator's HUD is its redeploy ring alone, drawn at full strength over the greyed model
diff --git a/test/render/champagne-hpbar.test.js b/test/render/champagne-hpbar.test.js
new file mode 100644
index 00000000..d05548d3
--- /dev/null
+++ b/test/render/champagne-hpbar.test.js
@@ -0,0 +1,43 @@
+// test/render/champagne-hpbar.test.js — 琳琅诗怀雅's 香槟炸弹 (token_10031_swire2_gdtrap) never shows an HP bar: PRTS 香槟炸弹
+// 备注 "即使自身生命值未满，模型下方也不会显示生命值槽" (the owner's report of 2026-10-08, 「香槟会掉血，会被治疗」). Allies
+// otherwise always draw one (render/units.js _updateHud). Only the bar changes; its HP and healing stay as they are.
+// Run: node --test test/render/champagne-hpbar.test.js
+
+import { test, before, after } from 'node:test';
+import assert from 'node:assert/strict';
+import { installFakePixi, fakeViewCtx } from './fakepixi.js';
+import { presetCamera } from '../../public/js/render/projection.js';
+
+let fake, UnitView;
+before(async () => {
+  fake = installFakePixi();
+  ({ UnitView } = await import('../../public/js/render/units.js'));
+});
+after(() => fake.restore());
+
+const cam = () => presetCamera('normal', { width: 1280, height: 720 });
+const view = (defId, id) => new UnitView(fakeViewCtx(fake.P, { cam }), { id, side: 'ally', kind: 'summon', defId, tier: 1, x: 11, y: 10, maxHp: 1000, hp: 1000 }, {});
+const frames = (v) => { for (let i = 0; i < 2; i++) v.update(1 / 60, cam(), i / 60); };
+const bar = (v) => [v.hpBg.visible, v.hpFill.visible, v.hpGhost.visible];
+
+test('香槟炸弹 shows no HP bar at full HP, below it, or healed back up', () => {
+  const bomb = view('token_10031_swire2_gdtrap', 1);
+  frames(bomb);
+  assert.deepEqual(bar(bomb), [false, false, false], 'full HP');
+  bomb.sync({ x: 11, y: 10, hp: 860, maxHp: 1000, sp: 0, spMax: 0, flags: 0, anim: 0 }, 1);
+  frames(bomb);
+  assert.equal(bomb.hp, 860, 'the view keeps its HP');
+  assert.deepEqual(bar(bomb), [false, false, false], 'hurt (活性源石: 70 true damage a second)');
+  bomb.sync({ x: 11, y: 10, hp: 1000, maxHp: 1000, sp: 0, spMax: 0, flags: 0, anim: 0 }, 2);
+  frames(bomb);
+  assert.deepEqual(bar(bomb), [false, false, false], 'healed');
+});
+
+test('another summon still draws its HP bar, full or hurt', () => {
+  const other = view('token_10000_silent_healrb', 2);
+  frames(other);
+  assert.deepEqual(bar(other), [true, true, true]);
+  other.sync({ x: 11, y: 10, hp: 400, maxHp: 1000, sp: 0, spMax: 0, flags: 0, anim: 0 }, 1);
+  frames(other);
+  assert.deepEqual(bar(other), [true, true, true]);
+});

From 1e78648ad45e3f3c61c1396fdad3035c0052042c Mon Sep 17 00:00:00 2001
From: sganggs <sganggs@users.noreply.github.com>
Date: Thu, 8 Oct 2026 19:18:01 +0800
Subject: [PATCH 5/7] =?UTF-8?q?feedback7=20R22-RENDER:=20closed=20eyes=20s?=
 =?UTF-8?q?tay=20closed=20without=20the=20stencil=20masks=20=E2=80=94=20th?=
 =?UTF-8?q?e=20eyelid=20clips'=20covered=20slots=20hide=20when=20their=20c?=
 =?UTF-8?q?entre=20leaves=20the=20clip=20polygon=20(GitHub=20#177,=20re-im?=
 =?UTF-8?q?plemented=20from=20PR=20#384=20by=20@Convey123);=20golden:=20un?=
 =?UTF-8?q?changed?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The eyelids of 佩佩, 仇白, 隐德来希, 琳琅诗怀雅 and other models are Spine clipping attachments: the polygon is the eye's
opening and the eyeball / eye-white meshes drawn after it are clipped to it, so a blink or a knock-down closes the eye
through the mask. render/app.js pickClipping keeps the masks only for a lone clipped skeleton at high quality, so in a
battle the eyeballs showed through the closed lids. SpineActor._eyeMaskFallback now runs after each update while the
masks are off: it walks the draw order like pixi-spine (from a slot whose attachment in force is a clip, to its
endSlot — any skin) and hides the slot container of a covered slot whose drawn centre (a mesh's mean vertex, a region's
quad centre) lies outside the clip polygon [ASSUMED: all or nothing per slot]; turning the masks on shows them again.

PR #384's version hid `slot.currentSprite`, which pixi-spine leaves null on a mesh slot — every covered slot of the
417 local operator skeletons' 73 clipped ones is a mesh (313) or a region (54; regions have no worldVerticesLength, so
it never measured them) — and its test stubbed a currentSprite onto every slot, so nothing was hidden in the game. Kept
from it: the diagnosis, the ray-casting pointInPolygon and the key-frame expectations.

Tests: test/render/eyemask.test.js (new, 7, on real runtime objects — the official skeletons in @pixi-spine/runtime-3.8's
real Spine, @pixi/core display objects with a 16 px canvas stand-in, the real SpineActor: the eyeballs are meshes in
the clip's container; 佩佩 / 仇白 Die and 隐德来希 / 琳琅诗怀雅 Idle hide exactly the eye slots in the closed frames and
nothing open; a 30 Hz sweep of six clips; masks on hide nothing, turning them on shows all) 7/7 — the five skeleton tests
skip without public/assets (not committed; npm run assets), and fail on PR #384's code; render unitview, enemy attack
clips, texas skill clip 45/45.
---
 public/js/render/app.js     |   5 +-
 public/js/render/spine.js   |  99 ++++++++++++++++++++++++--
 test/render/eyemask.test.js | 135 ++++++++++++++++++++++++++++++++++++
 3 files changed, 230 insertions(+), 9 deletions(-)
 create mode 100644 test/render/eyemask.test.js

diff --git a/public/js/render/app.js b/public/js/render/app.js
index 40b505a7..3370685b 100644
--- a/public/js/render/app.js
+++ b/public/js/render/app.js
@@ -1569,8 +1569,9 @@ export async function createFieldView(host, options = {}) {
   // Crowded fields render skeletons through staggered RenderTexture impostors (units.js): the interval grows with
   // the number of Spine units so the per-frame vertex work stays roughly constant (hysteresis: re-evaluated
   // every 30 frames). Prep and ordinary fields keep full-rate direct rendering.
-  // Spine clipping masks (only eyeball clips on the current roster, invisible at chibi scale) each cost a stencil
-  // render-pass break (~2–5 ms of GPU on tiled GPUs): kept only for a lone clipped skeleton at high quality
+  // Spine clipping masks (the eyelids on the current roster) each cost a stencil render-pass break (~2–5 ms of GPU on
+  // tiled GPUs): kept only for a lone clipped skeleton at high quality; without them SpineActor hides the eyeball slots a
+  // closed lid would cut (GitHub #177, spine.js _eyeMaskFallback)
   let clipAllowed = true;
   function pickClipping() {
     let n = 0;
diff --git a/public/js/render/spine.js b/public/js/render/spine.js
index 8025f17b..d86bce68 100644
--- a/public/js/render/spine.js
+++ b/public/js/render/spine.js
@@ -62,20 +62,53 @@ export function windUpPlan(loopDur, hit, interval, lead) {
   return { ts, tsWind, start };
 }
 
-/** Whether any skin of the skeleton data has a clipping attachment (pixi-spine AttachmentType.Clipping = 6). */
+/** A clipping attachment (pixi-spine AttachmentType.Clipping = 6). */
+const isClip = (a) => !!a && (a.type === 6 || a.constructor?.name === 'ClippingAttachment' || ('endSlot' in a && 'vertices' in a && !('uvs' in a)));
+
+/** Whether any skin of the skeleton data has a clipping attachment. */
 export function hasClipping(data) {
   try {
     for (const skin of data?.skins || []) {
       const list = typeof skin.getAttachments === 'function' ? skin.getAttachments() : [];
-      for (const e of list) {
-        const a = e && e.attachment;
-        if (a && (a.type === 6 || a.constructor?.name === 'ClippingAttachment' || ('endSlot' in a && 'vertices' in a && !('uvs' in a)))) return true;
-      }
+      for (const e of list) if (isClip(e && e.attachment)) return true;
     }
   } catch { /* unknown runtime shape: assume none */ }
   return false;
 }
 
+/**
+ * Is (x, y) inside the polygon of `n` points `pts` (flat [x0, y0, x1, y1, …])? Ray casting (PR #384 by @Convey123).
+ */
+export function pointInPolygon(x, y, pts, n) {
+  let inside = false;
+  for (let i = 0, j = n - 1; i < n; j = i++) {
+    const xi = pts[i * 2], yi = pts[i * 2 + 1], xj = pts[j * 2], yj = pts[j * 2 + 1];
+    if ((yi > y) !== (yj > y) && x < ((xj - xi) * (y - yi)) / (yj - yi) + xi) inside = !inside;
+  }
+  return inside;
+}
+
+/**
+ * World centre of what a slot draws, into `out` ([x, y]); false when it draws nothing measurable. A mesh: the mean of its
+ * world vertices (`buf` grows to fit); a region: its quad's centre — the attachment's (x, y) through the bone (the four
+ * corners sit symmetrically around it; RegionAttachment.computeWorldVertices takes a bone in runtime 3.8, a slot in 4.1).
+ */
+function slotCentre(slot, att, buf, out) {
+  const n = att.worldVerticesLength | 0;
+  if (n >= 2 && typeof att.computeWorldVertices === 'function') {
+    if (buf.v.length < n) buf.v = new Float32Array(n);
+    const v = buf.v;
+    att.computeWorldVertices(slot, 0, n, v, 0, 2);
+    let cx = 0, cy = 0;
+    for (let k = 0; k < n; k += 2) { cx += v[k]; cy += v[k + 1]; }
+    out[0] = cx / (n >> 1); out[1] = cy / (n >> 1);
+  } else if (att.region !== undefined && Number.isFinite(att.x) && Number.isFinite(att.y) && slot.bone) {
+    const b = slot.bone;
+    out[0] = b.a * att.x + b.b * att.y + b.worldX; out[1] = b.c * att.x + b.d * att.y + b.worldY;
+  } else return false;
+  return Number.isFinite(out[0]) && Number.isFinite(out[1]);
+}
+
 export class SpineActor {
   /**
    * @param {any} spineData PIXI.spine skeleton data
@@ -91,11 +124,12 @@ export class SpineActor {
     this.names = new Set((spineData.animations || []).map((a) => a.name));
     /**
      * Clipping attachments render as stencil masks (≈1.5 ms of GPU each per frame on tiled GPUs): such skeletons
-     * are drawn through the impostor atlas while clipping is on, and clipping is switched off (unclipped slots,
-     * visually negligible on battle chibis) when too many of them share a field (app.js budget).
+     * are drawn through the impostor atlas while clipping is on, and clipping is switched off when too many of them
+     * share a field (app.js budget) — then _eyeMaskFallback hides what a closed eyelid would cut (GitHub #177).
      */
     this.clipped = hasClipping(spineData);
     this.clipOn = true;
+    this._clipHidden = new Set(); // slot indexes the eyelid fallback hid in its last pass (_eyeMaskFallback)
     if (this.clipped) {
       const sp = this.spine;
       const orig = typeof sp.createGraphics === 'function' ? sp.createGraphics.bind(sp) : null;
@@ -134,6 +168,7 @@ export class SpineActor {
     on = !!on;
     if (!this.clipped || on === this.clipOn) return;
     this.clipOn = on;
+    if (on) this._showClipHidden();   // the stencil takes over from the eyelid fallback
     for (const slot of this.spine?.skeleton?.slots || []) {
       if (!slot.clippingContainer) continue;
       slot.clippingContainer.mask = on ? slot.currentGraphics || null : null;
@@ -546,6 +581,56 @@ export class SpineActor {
     if (!this.frozen) {
       try { this.spine.update(dt); } catch { /* a broken skeleton must not stop the frame */ }
     }
+    if (this.clipped && !this.clipOn) this._eyeMaskFallback();
+  }
+
+  /**
+   * The eyelids without the stencil masks (GitHub #177; PR #384 by @Convey123, re-implemented). On this roster the
+   * clipping attachments are eyelids: the polygon is the eye's opening and the eyeball / eye-white meshes drawn after
+   * it are clipped to it, so a closing eye (a blink, a knock-down) is hidden by the mask, not by the art. The masks
+   * are off on a crowded field or below high quality (render/app.js pickClipping), and the eyeballs showed through
+   * the closed lids (佩佩, 仇白, 隐德来希, 琳琅诗怀雅 …). While they are off, every slot a clip covers — walked in draw
+   * order from the clipping slot to its endSlot, with the attachments in force (any skin), as pixi-spine does — is
+   * hidden for the frame when the centre of what it draws lies outside the clip polygon [ASSUMED: all or nothing per
+   * slot, an approximation of the mask's cut]. pixi-spine shows every attached slot container again on each update.
+   */
+  _eyeMaskFallback() {
+    const sp = this.spine, skel = sp && sp.skeleton, boxes = sp && sp.slotContainers;
+    if (!skel || !Array.isArray(skel.drawOrder) || !boxes) return;
+    this._showClipHidden();   // undo the last pass (a pixi-spine update re-shows them anyway; a frozen one does not)
+    try {
+      const buf = this._clipBuf || (this._clipBuf = { v: new Float32Array(64), poly: new Float32Array(16), c: [0, 0] });
+      let pn = -1, end = null;   // pn: points of the clip in force (−1: none; < 3: degenerate, hides nothing)
+      for (const slot of skel.drawOrder) {
+        const att = typeof slot.getAttachment === 'function' ? slot.getAttachment() : slot.attachment;
+        if (isClip(att)) {
+          const n = att.worldVerticesLength | 0;
+          if (buf.poly.length < n) buf.poly = new Float32Array(n);
+          if (n >= 6) att.computeWorldVertices(slot, 0, n, buf.poly, 0, 2);
+          pn = n >> 1;
+          end = att.endSlot && att.endSlot !== slot.data ? att.endSlot : null;
+          continue;
+        }
+        if (pn < 0) continue;
+        const box = boxes[slot.data.index];
+        if (pn >= 3 && att && box && slotCentre(slot, att, buf, buf.c) && !pointInPolygon(buf.c[0], buf.c[1], buf.poly, pn)) {
+          box.visible = false;
+          this._clipHidden.add(slot.data.index);
+        }
+        if (end && slot.data === end) { pn = -1; end = null; }
+      }
+    } catch { /* an unknown runtime shape must never stop the frame */ }
+  }
+
+  /** Show the slot containers the fallback hid (those still drawing an attachment). */
+  _showClipHidden() {
+    if (!this._clipHidden.size) return;
+    const slots = this.spine?.skeleton?.slots, boxes = this.spine?.slotContainers;
+    for (const i of this._clipHidden) {
+      const slot = slots && slots[i];
+      if (boxes && boxes[i] && slot && (typeof slot.getAttachment === 'function' ? slot.getAttachment() : slot.attachment)) boxes[i].visible = true;
+    }
+    this._clipHidden.clear();
   }
 
   /** Model height in skeleton units (setup-pose bounds, else a chibi default). */
diff --git a/test/render/eyemask.test.js b/test/render/eyemask.test.js
new file mode 100644
index 00000000..da4288b2
--- /dev/null
+++ b/test/render/eyemask.test.js
@@ -0,0 +1,135 @@
+// test/render/eyemask.test.js — closed eyes without the stencil masks (GitHub #177; PR #384 by @Convey123, re-implemented):
+// the eyelids of these models are Spine clipping attachments, the masks are off on a crowded field or below high
+// quality (render/app.js pickClipping), and SpineActor._eyeMaskFallback (render/spine.js) hides a covered slot whose
+// centre leaves the clip polygon.
+//
+// Real runtime objects throughout: the official skeletons read by @pixi-spine/runtime-3.8, drawn by its real Spine
+// (pixi-spine's slot containers and meshes on @pixi/core display objects — a 16 px canvas stand-in is all it needs
+// headless) inside the real SpineActor. The eyeballs are meshes, drawn through `slot.currentMesh` — PR #384 hid
+// `slot.currentSprite` (null on a mesh slot) and its test stubbed one onto every slot, so nothing was hidden in the
+// game. The skeletons are not in the repository (public/assets: `npm run assets`): without them those tests skip.
+// Run: node --test test/render/eyemask.test.js
+
+import { test, describe, before } from 'node:test';
+import assert from 'node:assert/strict';
+import { existsSync, readFileSync } from 'node:fs';
+import path from 'node:path';
+import { createRequire } from 'node:module';
+import { fileURLToPath } from 'node:url';
+
+const ROOT = path.resolve(path.dirname(fileURLToPath(import.meta.url)), '../..');
+const require = createRequire(path.join(ROOT, 'package.json'));
+const ASSETS = JSON.parse(readFileSync(path.join(ROOT, 'data/assets.json'), 'utf8'));
+const dirOf = (id) => path.join(ROOT, 'public', 'assets', 'spine', 'op', id, 'front');
+const have = (id) => existsSync(path.join(dirOf(id), `${id}.skel`)) && existsSync(path.join(dirOf(id), `${id}.atlas`));
+const MODELS = ['char_4058_pepe', 'char_4082_qiubai', 'char_4010_etlchi', 'char_1033_swire2'];
+
+let SpineActor, pointInPolygon, rt, base, core;
+before(async () => {
+  // headless pixi: its shader-precision probe and Texture.WHITE ask for a canvas; no WebGL context is needed to build
+  // and update a Spine's display tree
+  class HeadlessCanvas { constructor() { this.width = 16; this.height = 16; } getContext(kind) { return kind === '2d' ? { fillStyle: '', fillRect() {}, clearRect() {}, drawImage() {} } : null; } }
+  globalThis.HTMLCanvasElement ??= HeadlessCanvas;
+  globalThis.document ??= { createElement: () => new HeadlessCanvas() };
+  rt = require('@pixi-spine/runtime-3.8');
+  base = require('@pixi-spine/base');
+  core = require('@pixi/core');
+  globalThis.PIXI = { spine: { Spine: rt.Spine } };   // SpineActor builds `new PIXI.spine.Spine(data)`
+  ({ SpineActor, pointInPolygon } = await import('../../public/js/render/spine.js'));
+});
+
+const cache = new Map();
+function skeletonData(id) {
+  if (!cache.has(id)) {
+    const atlas = new base.TextureAtlas(readFileSync(path.join(dirOf(id), `${id}.atlas`), 'utf8'), (line, cb) => cb(new core.BaseTexture(null, { width: 1024, height: 1024 })));
+    cache.set(id, new rt.SkeletonBinary(new rt.AtlasAttachmentLoader(atlas)).readSkeletonData(new Uint8Array(readFileSync(path.join(dirOf(id), `${id}.skel`)))));
+  }
+  return cache.get(id);
+}
+/** A real SpineActor of `id` with its manifest entry, clipping masks on or off. */
+function actor(id, clip) {
+  const a = new SpineActor(skeletonData(id), ASSETS.chars[id].spine.front);
+  a.setClipping(clip);
+  return a;
+}
+/** Slots whose container the fallback hid: still attached (pixi-spine shows those), yet not visible. */
+const hidden = (a) => a.spine.skeleton.slots.filter((s) => s.getAttachment() && a.spine.slotContainers[s.data.index].visible === false).map((s) => s.data.name).sort();
+/** Hidden slots `t` s into clip `clip` ('Die' through SpineActor.die — a knock-down — or 'Idle'), masks off. A fresh
+ *  actor per time: pixi-spine's state.update takes a delta. */
+function hiddenAt(id, clip, t) {
+  const a = actor(id, false);
+  if (clip === 'Die') a.die(); else a.spine.state.setAnimation(0, clip, true);
+  a.update(t);
+  return hidden(a);
+}
+
+test('pointInPolygon: inside / outside of a convex and a concave polygon', () => {
+  const square = [0, 0, 10, 0, 10, 10, 0, 10];
+  assert.equal(pointInPolygon(5, 5, square, 4), true);
+  for (const [x, y] of [[-1, 5], [11, 5], [5, -3]]) assert.equal(pointInPolygon(x, y, square, 4), false);
+  const l = [0, 0, 10, 0, 10, 4, 4, 4, 4, 10, 0, 10];   // an L: the notch is outside
+  assert.equal(pointInPolygon(6, 6, l, 6), false);
+  assert.equal(pointInPolygon(2, 6, l, 6), true);
+  assert.equal(pointInPolygon(8, 2, l, 6), true);
+});
+
+describe('eyelids on the official skeletons, drawn by the real pixi-spine runtime', { skip: !MODELS.every(have) && 'the operator skeletons are not in public/assets (npm run assets)' }, () => {
+  test('the eyeballs are meshes drawn through slot.currentMesh, inside the eyelid clip\'s container', () => {
+    const a = actor('char_4058_pepe', true);
+    a.update(0.1);
+    const slots = a.spine.skeleton.slots.filter((s) => /^F_[LR]_Eye_[BC]$/.test(s.data.name));
+    assert.equal(slots.length, 4);
+    const clip = a.spine.skeleton.slots.find((s) => s.clippingContainer);
+    for (const s of slots) {
+      assert.equal(s.getAttachment().constructor.name, 'MeshAttachment', s.data.name);
+      assert.ok(s.currentMesh && !s.currentSprite, `${s.data.name}: a mesh, no sprite`);
+      assert.equal(a.spine.slotContainers[s.data.index].parent, clip.clippingContainer, `${s.data.name} is clipped`);
+    }
+  });
+
+  test('佩佩 knocked down (Die): the four eyeball / eye-white slots hide once the eyes close (0.13 → 1.00 s), none before', () => {
+    for (const t of [0, 0.1]) assert.deepEqual(hiddenAt('char_4058_pepe', 'Die', t), [], `open at ${t}`);
+    for (const t of [0.3, 0.52, 1]) assert.deepEqual(hiddenAt('char_4058_pepe', 'Die', t), ['F_L_Eye_B', 'F_L_Eye_C', 'F_R_Eye_B', 'F_R_Eye_C'], `closed at ${t}`);
+  });
+
+  test('仇白 knocked down: both eyeballs hide once the eyes close', () => {
+    for (const t of [0, 0.1]) assert.deepEqual(hiddenAt('char_4082_qiubai', 'Die', t), [], `open at ${t}`);
+    for (const t of [0.2, 0.52, 1]) assert.deepEqual(hiddenAt('char_4082_qiubai', 'Die', t), ['F_L_Eyeball', 'F_R_Eyeball'], `closed at ${t}`);
+  });
+
+  test('隐德来希 / 琳琅诗怀雅 blink in Idle (2.13–2.37 s / 2.90–3.00 s): hidden then, never with the eyes open', () => {
+    for (const t of [0.5, 1.9, 3]) assert.deepEqual(hiddenAt('char_4010_etlchi', 'Idle', t), [], `隐德来希 open at ${t}`);
+    for (const t of [2.13, 2.25, 2.37]) assert.ok(hiddenAt('char_4010_etlchi', 'Idle', t).length >= 4, `隐德来希 blinking at ${t}`);
+    for (const t of [0.5, 2.6, 3.2]) assert.deepEqual(hiddenAt('char_1033_swire2', 'Idle', t), [], `琳琅诗怀雅 open at ${t}`);
+    for (const t of [2.9, 2.97, 3]) assert.deepEqual(hiddenAt('char_1033_swire2', 'Idle', t), ['F_H_L_Eyeball', 'F_H_L_Eyew', 'F_H_R_Eyeball', 'F_H_R_Eyew'], `琳琅诗怀雅 at ${t}`);
+  });
+
+  test('a whole clip sampled at 30 Hz: hiding is rare outside a knock-down and never takes more than the eyes', () => {
+    // [model, clip, seconds, share of frames with something hidden: at least, at most]
+    for (const [id, clip, dur, lo, hi] of [
+      ['char_4058_pepe', 'Idle', 4, 0, 0], ['char_4058_pepe', 'Die', 1.5, 0.5, 1],
+      ['char_4082_qiubai', 'Idle', 4, 0, 0.35], ['char_4082_qiubai', 'Die', 1, 0.5, 1],
+      ['char_4010_etlchi', 'Idle', 4, 0.02, 0.2], ['char_1033_swire2', 'Idle', 4, 0.01, 0.2],
+    ]) {
+      let hit = 0, frames = 0, most = 0;
+      for (let t = 0; t <= dur; t += 1 / 30) { const n = hiddenAt(id, clip, t).length; frames++; if (n) hit++; most = Math.max(most, n); }
+      assert.ok(hit / frames >= lo && hit / frames <= hi, `${id} ${clip}: ${Math.round(hit / frames * 100)} % of frames (want ${lo * 100}–${hi * 100} %)`);
+      assert.ok(most <= 8, `${id} ${clip}: at most ${most} slots in one frame`);
+    }
+  });
+
+  test('with the masks on nothing is hidden (the stencil cuts), and turning them back on shows what the fallback hid', () => {
+    const on = actor('char_4058_pepe', true);
+    on.die();
+    on.update(0.52);
+    assert.deepEqual(hidden(on), [], 'masks on: the fallback stays out');
+    const off = actor('char_4058_pepe', false);
+    off.die();
+    off.update(0.52);
+    assert.equal(hidden(off).length, 4, 'masks off: the closed eyes are hidden');
+    off.setClipping(true);
+    assert.deepEqual(hidden(off), [], 'shown again for the stencil');
+    const clip = off.spine.skeleton.slots.find((s) => s.clippingContainer);
+    assert.equal(clip.clippingContainer.mask, clip.currentGraphics, 'the mask is back on');
+  });
+});

From 6326dd4d0b2a944ef4b1c2c60806175b07ba1ed5 Mon Sep 17 00:00:00 2001
From: sganggs <sganggs@users.noreply.github.com>
Date: Thu, 8 Oct 2026 19:20:55 +0800
Subject: [PATCH 6/7] =?UTF-8?q?feedback7=20R22-RENDER:=20an=20attack=20see?=
 =?UTF-8?q?n=20late=20plays=20its=20whole=20clip=20from=20the=20wind-up=20?=
 =?UTF-8?q?when=20the=20rhythm=20leaves=20room=20for=20it=20=E2=80=94=20?=
 =?UTF-8?q?=E9=87=8D=E7=8A=AF's=20iron=20ball=20lifts=20before=20the=20sla?=
 =?UTF-8?q?m=20(#246=20by=20@TsangAsuna,=20accepted=20by=20the=20owner);?=
 =?UTF-8?q?=20golden:=20unchanged?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

SpineActor.attack() starts an attack that was not wound up (no look-ahead: a batch that arrived late) on its strike
frame — right for a quick rhythm, but for a slow clip-per-attack enemy the wind-up was cut out: 重犯 (Attack_grey
2.333 s, strike at 1.0 s, attacks every 3 s) showed the slam without the ball ever rising, and only 1.33 s of the clip.
The owner's decision of 2026-10-07 on #246: re-implement on the current spine.js so that, when the attack interval
leaves room for the whole clip, it plays once completely from the start. A clip-per-attack actor (enemies) with
interval ≥ the clip now plays it from 0 at its own speed for the whole clip, the strike landing a little late; a
quicker rhythm keeps the strike-frame start, and operators' looping attacks are unchanged (the PR's condition had it
the other way round: it changed the looping attacks and left out the clip-per-attack enemies it was written for).

Tests: test/render/feedback2-enemy-attack-clip.test.js (+1: 重犯 plays the whole clip from its wind-up, a quicker rhythm
and an operator start on the strike frame) 5/5; render eyemask, unitview, texas skill clip, skill idle 51/51.
---
 public/js/render/spine.js                     | 10 ++++++---
 .../feedback2-enemy-attack-clip.test.js       | 21 +++++++++++++++++++
 2 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/public/js/render/spine.js b/public/js/render/spine.js
index d86bce68..e805074e 100644
--- a/public/js/render/spine.js
+++ b/public/js/render/spine.js
@@ -367,9 +367,13 @@ export class SpineActor {
     this.windUntil = null;
     this.wound = false;
     if (!wasAttacking) {
-      // not wound up (no look-ahead, e.g. a batch that arrived late): the sim already resolved the hit, so show
-      // the strike frame now
-      this._play(clip.loop, !single, { timeScale: ts, start: hit, mix: 0.06 });
+      // not wound up (no look-ahead, e.g. a batch that arrived late): the sim already resolved the hit, so show the
+      // strike frame now — unless a clip-per-attack actor's rhythm leaves room for the whole clip (interval ≥ clip):
+      // then the clip plays complete from its wind-up at its own speed, the strike a little late (重犯's iron ball
+      // lifts before the slam; #246 by @TsangAsuna, accepted by the owner on 2026-10-07)
+      const whole = per && this.interval >= loopDur;
+      if (whole) this.attackUntil = this.clock + loopDur / ts;
+      this._play(clip.loop, !single, { timeScale: ts, start: whole ? 0 : hit, mix: 0.06 });
     } else if (single) {
       const e = this.spine.state.tracks[0];
       if (e) e.timeScale = ts;
diff --git a/test/render/feedback2-enemy-attack-clip.test.js b/test/render/feedback2-enemy-attack-clip.test.js
index 999877a1..5c560624 100644
--- a/test/render/feedback2-enemy-attack-clip.test.js
+++ b/test/render/feedback2-enemy-attack-clip.test.js
@@ -71,6 +71,27 @@ test('an enemy attacking quicker than its clip plays it faster, one clip per att
   assert.equal(a.current, 'Move', 'the rest of the clip at 2×: 0.23 s');
 });
 
+// #246 (by @TsangAsuna, accepted by the owner on 2026-10-07): seen late, an attack whose rhythm leaves room for the whole
+// clip plays it complete from the wind-up — 重犯's iron ball lifts before the slam instead of the slam appearing alone
+test('an attack seen late plays the whole clip from its wind-up when the rhythm leaves room for it (重犯), else from the strike frame', () => {
+  const LIFBOS = 'enemy_1121_lifbos';   // 重犯: Attack_grey 2.333 s, strike at 1.0 s; attacks every 3 s
+  const a = actor(LIFBOS, true);
+  a.attack(3);
+  assert.equal(a.current, 'Attack_grey');
+  assert.equal(track(a).trackTime, 0, 'from the wind-up (the ball lifts), not the 1.0 s strike frame');
+  assert.equal(track(a).timeScale, 1, 'at its own speed');
+  run(a, 2.25);
+  assert.equal(a.current, 'Attack_grey', 'the whole 2.333 s clip plays (it used to end 1.333 s after the strike frame)');
+  run(a, 0.15);
+  assert.equal(a.current, 'Move_grey', 'then the resting clip');
+  const quick = actor(LIFBOS, true);
+  quick.attack(2);                                 // quicker than the clip: no room for the wind-up
+  assert.ok(Math.abs(track(quick).trackTime - 1) < 1e-9, 'from the strike frame');
+  const op = actor(LIFBOS, false);
+  op.attack(3);                                    // an operator's looping attack is unchanged
+  assert.ok(Math.abs(track(op).trackTime - 1) < 1e-9);
+});
+
 test('an operator keeps its attack loop stretched over the attack rhythm (unchanged)', () => {
   const a = actor(JSHOOT, false);
   a.attack(2.7);

From 7a33bc7e192264978c580d58001735014a7cc4ad Mon Sep 17 00:00:00 2001
From: sganggs <sganggs@users.noreply.github.com>
Date: Thu, 8 Oct 2026 20:40:33 +0800
Subject: [PATCH 7/7] =?UTF-8?q?feedback7=20R22-RENDER:=20a=20unit=20killed?=
 =?UTF-8?q?=20on=20the=20step=20of=20its=20push=20lies=20where=20the=20sim?=
 =?UTF-8?q?=20put=20it=20=E2=80=94=20a=20dying=20view's=20sample=20anchors?=
 =?UTF-8?q?=20the=20slide=20too=20(Grok's=20review=20of=20fb7-render,=20HI?=
 =?UTF-8?q?GH);=20golden:=20unchanged?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

A push and a kill on the same sim step bring the displace fx and the 'die' together: the view died before its slide
could anchor, and render/app.js syncBattle gives a dying view only its position (v.x = s.x) — never sync(), the only
place that set slide.live — so update() held the slide's start until its 0.5 s timeout, past the 0.8 s DIE window,
and dropped it: the body stayed on its pre-push tile (8.852 instead of the sim's 10.5; a summoned enemy and a flyer
alike). The per-view step of syncBattle is now units.js syncView (unchanged for living, device and revived views); its
dying branch calls UnitView.followSample, the position part of sync(): the sample anchors a slide from `at` on, and is
the position only when no slide owns it. A slide whose destination snapshot never shows (the unit left the snapshots)
now goes on to the fx's destination after the 0.5 s hold instead of being dropped where it started.

The frame-order test fed the view with sync() after its death and stepped the battle through the harness (whose
step() drained the events away from the test's own queue): it now steps the battle itself and goes through syncView.

Tests: test/render/unitview.test.js 38/38 — the app.js frame order over real battles: a 1.7-tile push; a kill on the
push's step for a route enemy, a summoned one and a flyer (the three failed before: bodies at 8.852 / 7.262 / 8.852)
and a kill 6 ticks later — the body ends where the sim's lies, every frame step < 0.35 tiles, no step back for the
same-step kills; a never-shown slide goes to the destination. Render interp, attack recovery, champagne, eyemask,
enemy attack clips, sim displace-fx: 94/94 with unitview.
---
 public/js/render/app.js      |  6 +--
 public/js/render/units.js    | 33 +++++++++---
 test/render/unitview.test.js | 99 ++++++++++++++++++++++++------------
 3 files changed, 94 insertions(+), 44 deletions(-)

diff --git a/public/js/render/app.js b/public/js/render/app.js
index 3370685b..b552e6ea 100644
--- a/public/js/render/app.js
+++ b/public/js/render/app.js
@@ -117,7 +117,7 @@ import { fxForm } from '../../../shared/protocol.js';
 import { Camera, presetCamera, lerpCamera, easeInOutCubic, pickTile, normRect } from './projection.js';
 import { SnapshotBuffer, frameTime } from './interp.js';
 import { TileField } from './tiles.js';
-import { UnitView, ItemView, DeviceView, FORMS } from './units.js';
+import { UnitView, ItemView, DeviceView, FORMS, syncView } from './units.js';
 import { FxSystem, ensureDamageFonts } from './fx.js';
 import { createDragController, pieceTile } from './drag.js';
 import { backdropTextures, shadowTexture, refreshTierChips, silhouetteTexture } from './textures.js';
@@ -1500,9 +1500,7 @@ export async function createFieldView(host, options = {}) {
       if (!v) v = battleView(id) || createUnknown(id, s);
       if (!v) continue;
       if (!v._seen) { v._seen = true; v.fadeIn = 0; }
-      if (v.alive || v.info?.kind === 'device') v.sync(s, renderT);
-      else if (v.dying > 0) { v.x = s.x; v.y = s.y; }
-      else if (s.anim !== ANIM.DIE && s.hp > 0) { v.revive?.(); v.sync(s, renderT); }
+      syncView(v, s, renderT);
     }
     // knocked-out operators waiting to redeploy (b.snap `down`, user playtest #4 item 9): their view stays on the
     // field knocked down under a redeploy ring (UnitView.setDown) — made on the spot for one already down when this
diff --git a/public/js/render/units.js b/public/js/render/units.js
index 206c8278..b4866d17 100644
--- a/public/js/render/units.js
+++ b/public/js/render/units.js
@@ -110,6 +110,16 @@ export function dieClipDur(entry) {
   const d = Object.hasOwn(durs, name) ? Number(durs[name]) : NaN;
   return Number.isFinite(d) && d > 0 ? d : 0;
 }
+/**
+ * render/app.js syncBattle's step for one view and its interpolated sample `s` at render time `t`: a living view (or a
+ * device) takes the whole sample; a dying one only the position — its DIE window in the snapshots; one shown alive
+ * again (redeployed without an event) stands up first.
+ */
+export function syncView(v, s, t) {
+  if (v.alive || v.info?.kind === 'device') v.sync(s, t);
+  else if (v.dying > 0) { if (typeof v.followSample === 'function') v.followSample(s, t); else { v.x = s.x; v.y = s.y; } }
+  else if (s.anim !== ANIM.DIE && s.hp > 0) { v.revive?.(); v.sync(s, t); }
+}
 /** World step (x = col, y = row) of a direction. */
 export const DIR_STEP = Object.freeze({ UP: [0, 1], RIGHT: [1, 0], DOWN: [0, -1], LEFT: [-1, 0] });
 const nowMs = () => (globalThis.performance ? globalThis.performance.now() : Date.now());
@@ -763,11 +773,7 @@ export class UnitView {
     // the element gauge shown (b.snap `elem`): element, fill 0..1, cooldown end (game s) and length
     this.el = typeof s.el === 'string' ? s.el : null;
     this.elFill = this.el ? s.elFill || 0 : 0; this.elUntil = this.el ? s.elUntil || 0 : 0; this.elDur = this.el ? s.elDur || 0 : 0;
-    // a push / pull slide owns the drawn position (slideTo): the sample only anchors where it eases to, from the
-    // snapshot that carries the destination on (`at`) — before that the sample is still sliding or snapping there
-    const sl = this.slide;
-    if (!sl) { this.x = s.x; this.y = s.y; }
-    else if (!(t < sl.at)) { sl.lx = s.x; sl.ly = s.y; sl.live = true; }
+    this.followSample(s, t);
     this.flying = !!(s.flags & UF.FLYING) || this.info.motion === 'FLY';
     // enemies keep to the road plane: ground enemies only ever walk low tiles (a rounding step onto a block edge must not
     // pop them up), and a flyer hovers FLY_HOVER above the road whatever tile it crosses — the official lift is one
@@ -797,6 +803,18 @@ export class UnitView {
 
   setWorld(x, y, z = 0) { this.x = x; this.y = y; this.z = z; }
 
+  /**
+   * The sampled position: the view's — unless a push / pull slide owns it (slideTo), which only anchors where it eases
+   * to on it, from the snapshot that carries the destination on (`at`; before that the sample is still sliding or
+   * snapping there). sync() starts with it; a dying view gets nothing else (syncView: the DIE window of the snapshots),
+   * so a unit killed on the step of its push still lands where the sim put the body (Grok's review of fb7-render).
+   */
+  followSample(s, t) {
+    const sl = this.slide;
+    if (!sl) { this.x = s.x; this.y = s.y; }
+    else if (!(t < sl.at)) { sl.lx = s.x; sl.ly = s.y; sl.live = true; }
+  }
+
   /**
    * Slide to a displacement's destination (推拉, the `displace` fx at (x, y)) instead of appearing there (DISPLACE_SLIDE).
    * `at` (game s): the time of the snapshot that carries the destination — render/app.js starts the slide as soon as the
@@ -1051,8 +1069,9 @@ export class UnitView {
       if (this.down) this.slide = null;   // a knocked-down view lies on its tile (setDown)
       else if (!sl.live) {
         this.x = sl.sx; this.y = sl.sy;
-        // never shown (the unit left the snapshots, a stalled stream): the snapshot takes the view back
-        if ((sl.wait += dt) > 0.5) this.slide = null;
+        // the destination's snapshot never shown (the unit left the snapshots, a stalled stream): it slides to the
+        // destination the fx named
+        if ((sl.wait += dt) > 0.5) sl.live = true;
       } else {
         if (!sl.run) { sl.run = true; sl.ox = sl.sx - sl.lx; sl.oy = sl.sy - sl.ly; }
         const step = Math.min(dt, 0.1);                // a hidden tab's catch-up frame must not overshoot
diff --git a/test/render/unitview.test.js b/test/render/unitview.test.js
index 1e033118..851dc19f 100644
--- a/test/render/unitview.test.js
+++ b/test/render/unitview.test.js
@@ -595,49 +595,59 @@ describe('a push / pull slide (推拉: the official impulse under friction)', ()
     assert.ok(Math.abs(v.x - landed) < 0.05, `landed on the walking enemy (${landed.toFixed(3)} → ${v.x.toFixed(3)})`);
   });
 
-  test('a slide that is never shown (the unit left the snapshots) hands the view back', async () => {
+  test('a slide whose destination snapshot never shows (the unit left the snapshots) goes to the fx\'s destination', async () => {
     const v = await view(13);
     v.slideTo(7.7, 12, { at: 3 });
-    for (let i = 0; i < 40; i++) v.update(1 / 60, cam(), 0);
+    for (let i = 0; i < 24; i++) v.update(1 / 60, cam(), 0);
+    assert.equal(v.x, 5, 'held while the snapshot may still come');
+    for (let i = 0; i < 30; i++) v.update(1 / 60, cam(), 0);
     assert.equal(v.slide, null);
+    assert.equal(v.x, 7.7, 'then slid to where the push put it');
     v.sync({ x: 6.1, y: 12, hp: 100, maxHp: 100, sp: 0, spMax: 0, flags: 0, anim: 1 }, 3.4);
-    assert.equal(v.x, 6.1);
+    assert.equal(v.x, 6.1, 'snapshots drive it again');
   });
 });
 
-// the app.js frame order (render/app.js: processEvents takes the events ≤ renderT, then syncBattle's look-ahead starts a
-// slide for a `displace` fx still queued up to the next snapshot, then sample → sync, then update) run over a real
-// battle: a pushed enemy is drawn sliding, not snapped
+// the app.js frame order (render/app.js: processEvents takes the events ≤ renderT — a 'die' kills the view —, then
+// syncBattle's look-ahead starts a slide for a `displace` fx still queued up to the next snapshot, then each sampled unit
+// goes through syncView — a dying view takes only the position —, then update) run over a real battle: a pushed enemy is
+// drawn sliding, not snapped, and one killed by the push lies where the sim put it
 describe('a push through SnapshotBuffer and UnitView in the app.js frame order (PR #380)', () => {
-  async function pushed({ kill = false } = {}) {
+  /**
+   * A real battle: an enemy (`kind` 'route': on its route; 'summon': spawned mid-battle; 'flyer': a flying one) pushed
+   * 1.7 tiles at 3 s, killed `killDelay` ticks later when `kill`. Returns the drawn x of every frame from renderT 2.8 to
+   * 4.6, the sim's position right after the push and where the body lies (the sim's position at the kill).
+   */
+  async function pushed({ kill = false, killDelay = 0, kind = 'route' } = {}) {
     const { makeBattle, enemyRec } = await import('../helpers/battleHarness.js');
     const { SnapshotBuffer } = await import('../../public/js/render/interp.js');
     const { snapFrame } = await import('../../server/match/fields.js');
-    const h = makeBattle({ defs: { enemies: { enemy_walker: enemyRec({ key: 'enemy_walker', hp: 1e6, speed: 0.8 }) } },
-      enemies: [{ key: 'enemy_walker', time: 0, route: 0 }], content: 'none', autoFinish: false, timeLimit: 60 });
+    const { syncView } = await import('../../public/js/render/units.js');
+    const rec = enemyRec({ key: 'enemy_walker', hp: 1e6, speed: 0.8, ...(kind === 'flyer' ? { motion: 'FLY' } : {}) });
+    const h = makeBattle({ defs: { enemies: { enemy_walker: rec } }, enemies: kind === 'summon' ? [] : [{ key: 'enemy_walker', time: 0, route: 0 }],
+      content: 'none', autoFinish: false, timeLimit: 60 });
     const frames = [];
-    let e = null, info = null, moved = 0, dest = null;
-    for (let i = 0; i < 30 * 6; i++) {
-      h.step();
+    let e = null, info = null, moved = 0, dest = null, since = -1, body = null;
+    for (let i = 0; i < 30 * 7; i++) {
+      h.b.step();   // the battle's own step: h.step() would drain the events into h.events
+      if (kind === 'summon' && !e && h.b.time >= 1) e = h.b.spawnEnemy('enemy_walker', { pos: [10, 8] });   // (h.spawn drains too)
       e = e || h.enemy('enemy_walker');
-      if (!moved && h.b.time >= 3) {
-        moved = h.b.displace(e, { x: 1, y: 0 }, 1.7);
-        dest = e.x;
-        if (kill) h.b.kill(e, null);
-      }
+      if (!moved && e && h.b.time >= 3) { moved = h.b.displace(e, { x: 1, y: 0 }, 1.7); dest = e.x; since = 0; }
+      else if (since >= 0) since++;
+      if (kill && since === killDelay) { h.b.kill(e, null); body = e.x; }
       if (i % 3 === 2) {
         const ev = h.b.drainEvents();
-        info = info || ev.find((x) => x[0] === 'spawn')?.[1];
+        info = info || ev.find((x) => x[0] === 'spawn' && e && x[1].id === e.id)?.[1];
         const s = h.b.snapshot();
         frames.push({ at: s.t / 2, snap: snapFrame('f', s), ev, gt: s.t });
       }
     }
     assert.ok(moved > 1, `the sim pushed it ${moved} tiles`);
-    const ctx = fakeViewCtx(fake.P, { cam });
-    const v = new UnitView(ctx, { ...info, id: e.id }, {});
+    assert.equal(e.alive, !kill);
+    const v = new UnitView(fakeViewCtx(fake.P, { cam }), info, {});
     const buf = new SnapshotBuffer(), sample = new Map(), xs = [];
     const start = (ev, at) => { if (ev[0] === 'fx' && ev[1] === 'displace' && ev[4]?.id === e.id) v.slideTo(Number(ev[2]), Number(ev[3]), at == null ? {} : { at }); };
-    for (let f = 0, fi = 0; f < 60 * 3; f++) {
+    for (let f = 0, fi = 0; f < 60 * 4; f++) {
       const now = f / 60;
       for (; fi < frames.length && frames[fi].at <= now; fi++) { buf.push(frames[fi].snap, frames[fi].at); buf.pushEvents(frames[fi].ev, frames[fi].at, frames[fi].gt); }
       const renderT = buf.update(now);
@@ -646,28 +656,51 @@ describe('a push through SnapshotBuffer and UnitView in the app.js frame order (
       const at = buf.nextSnapT(renderT);
       if (at > renderT) buf.forEachUpcoming(renderT, at, (ev) => start(ev, at));
       buf.sample(renderT, sample);
-      if (sample.get(e.id)) v.sync(sample.get(e.id), renderT);
+      if (sample.get(e.id)) syncView(v, sample.get(e.id), renderT);
       v.update(1 / 60, cam(), now);
-      if (renderT > 2.8 && renderT < 3.8) xs.push(v.x);
+      if (renderT > 2.8 && renderT < 4.6) xs.push(v.x);
     }
-    return { xs, dest };
+    return { xs, dest, body };
   }
+  /** The largest frame-to-frame step, the frames moving, the slide's first frame and any step back after it. */
+  const steps = (xs) => {
+    let big = 0, moving = 0, back = false;
+    const from = xs.findIndex((x, i) => i > 0 && x > xs[i - 1] + 0.01);   // the slide's first frame (it walked left before)
+    for (let i = 1; i < xs.length; i++) {
+      const d = xs[i] - xs[i - 1];
+      big = Math.max(big, Math.abs(d)); if (Math.abs(d) > 0.02) moving++;
+      if (from > 0 && i > from && d < -1e-9) back = true;
+    }
+    return { big, moving, from, back };
+  };
 
   test('a 1.7-tile push is drawn over a dozen frames, every frame a step under 0.35 tiles', async () => {
     const { xs } = await pushed();
-    let big = 0, moving = 0;
-    for (let i = 1; i < xs.length; i++) { const d = Math.abs(xs[i] - xs[i - 1]); big = Math.max(big, d); if (d > 0.02) moving++; }
+    const { big, moving } = steps(xs);
     assert.ok(moving >= 8, `${moving} frames show it moving (the bare interpolator: 3)`);
     assert.ok(big < 0.35, `largest step ${big.toFixed(3)} tiles (the bare interpolator: 0.58)`);
   });
 
-  test('killed right after the push, the body slides on to where the sim left it and stays there', async () => {
-    const { xs, dest } = await pushed({ kill: true });
-    assert.ok(Math.abs(xs[xs.length - 1] - dest) < 0.011, `${xs[xs.length - 1]} vs ${dest}`);
-    const from = xs.findIndex((x, i) => i > 0 && x > xs[i - 1] + 0.01);   // the slide's first frame (it walked left before)
-    assert.ok(from > 0);
-    for (let i = from; i < xs.length; i++) assert.ok(xs[i] >= xs[i - 1] - 1e-9, `never back towards where it stood (frame ${i})`);
-  });
+  // a unit killed on the very step of its push: its 'die' comes due with the displace fx, so its view is dying before the
+  // slide can anchor — and syncBattle gives a dying view only its position (syncView). The slide used to stay on hold,
+  // be dropped after 0.5 s, past the 0.8 s DIE window, and leave the body on its pre-push tile (Grok's review of fb7-render)
+  for (const [name, o] of [
+    ['killed on the step of the push', { kind: 'route', killDelay: 0 }],
+    ['a summoned enemy killed on the step of the push', { kind: 'summon', killDelay: 0 }],
+    ['a flyer killed on the step of the push', { kind: 'flyer', killDelay: 0 }],
+    ['killed 6 ticks after the push', { kind: 'route', killDelay: 6 }],
+  ]) {
+    test(`${name}: the body slides on to where the sim put it and stays there, no frame stepping 0.35 tiles`, async () => {
+      const { xs, dest, body } = await pushed({ kill: true, ...o });
+      const { big, moving, from, back } = steps(xs);
+      if (!o.killDelay) assert.equal(body, dest, 'killed where the push put it');
+      assert.ok(Math.abs(xs[xs.length - 1] - body) < 0.011, `lies at ${xs[xs.length - 1].toFixed(3)}, the sim's body at ${body.toFixed(3)}`);
+      assert.ok(from > 0 && moving >= 8, `${moving} frames show it sliding`);
+      assert.ok(big < 0.35, `largest step ${big.toFixed(3)} tiles`);
+      // (killed later, it walked back down its route a little first: the body eases onto that)
+      if (!o.killDelay) assert.ok(!back, 'never back towards where it stood');
+    });
+  }
 });
 
 // PR #380, death: a flyer holds its lift through the Die clip (the official client drops its fly offset in