feedback1 WD: form changes survive the client's catch-up frames, hidden tab and pre-entry buffer

Every setForm fx now carries 'form' (shared/protocol.js fxForm). The runner keeps
these fx in catch-up frames (keepsState), holds the state-bearing events of the
battle on screen while the tab is hidden and delivers them with the first frame
back (re-entering from the field meta past HELD_MAX); screens/game.js buffers
them before a field is entered. A husk beaten while its stand-up clip plays dies
on the husk's clip. 幽灵 form cited from PRTS; 特战术师 flyer question recorded.

public/js/battle/runner.js

@@ -13,6 +13,11 @@
 //     and b.result (compactResult) at the end; applies b.pool (LocalBossPool.sync) and b.end (forceEnd / takeover),
 //   * keeps an authoritative battle running while the tab is hidden (a 250 ms interval pump; browsers throttle it to
 //     ~1 Hz, the bounded fast-forward absorbs that); the server deadline + takeover cover anything worse.
+// A frame that fast-forwards (catch-up) passes on only the state-bearing events (keepsState: spawns, deaths, deploys,
+// statuses, skills, leaks and the fx that change an enemy's model form — shared/protocol.js fxForm); while the tab is
+// hidden the battle on screen keeps the same events (≤ HELD_MAX, else the view re-enters from the field meta) and the
+// first frame back delivers them, so the view still knows every unit and every enemy's current form (player report #5
+// after 0.1.0: a 转译基底·α that changed form during a stall or in a background tab died in its first-form model).
 // Display replicas (a teammate's field after the own battle, 联防 observers, the partner of a boss pair) run the same
 // spec fast-forwarded to the server's clock (`elapsed`) and never report.
 // A b.result lost with the socket (the request failed DISCONNECTED / OFFLINE, or timed out twice) is kept and sent
@@ -53,7 +58,7 @@
 
 import { net as appNet } from '../net.js';
 import { store as appStore } from '../store.js';
-import { unitStatsEntry } from '../../../shared/protocol.js';
+import { unitStatsEntry, fxForm } from '../../../shared/protocol.js';
 
 const TICK = 1 / 30;
 /** Fast-forward budget per frame (ticks) when far behind. */
@@ -62,6 +67,13 @@ export const CATCHUP_TICKS = 240;
 const PREPARE_SLICE = 600;
 const MAX_ENTRIES = 4;
 const STATE_EV = new Set(['spawn', 'die', 'deploy', 'status', 'skill', 'leak']);
+/**
+ * The b.ev tuples a catch-up frame or the hidden-tab backlog keeps: the state-bearing kinds, and every fx that sets an
+ * enemy's model form (shared/protocol.js fxForm — dropped, the view kept the old model: player report #5 after 0.1.0).
+ */
+export const keepsState = (x) => Array.isArray(x) && (STATE_EV.has(x[0]) || fxForm(x) !== undefined);
+/** Hidden-tab backlog cap (tuples) of the battle on screen; beyond it the view re-enters from the field meta. */
+export const HELD_MAX = 3000;
 /** Data files the simulation reads (DataSource + content/support gameData()). */
 export const SIM_DATA_FILES = Object.freeze(['chess', 'enemies', 'tokens', 'stages', 'waves', 'bonds', 'items', 'garrisons', 'bands', 'effects']);
 
@@ -304,16 +316,33 @@ export function createBattleRunner(deps) {
   }
 
   function emitFrame(e, catchingUp) {
+    // the hidden-tab backlog overflowed: the view starts again from the field meta (UnitInfo carries every unit's form)
+    if (e.stale) { show(e); return; }
     let ev = [];
     try { ev = e.battle.drainEvents() || []; } catch { ev = []; }
     const gt = Number(e.battle.time) || 0;
-    if (ev.length) {
-      const list = catchingUp ? ev.filter((x) => Array.isArray(x) && STATE_EV.has(x[0])) : ev;
+    const held = e.held;
+    if (held.length) e.held = [];
+    if (ev.length || held.length) {
+      const list = held.concat(catchingUp ? ev.filter(keepsState) : ev);
       if (list.length) emit('ev', { t: 'b.ev', fieldId: e.fieldId, gt, ev: list });
     }
     try { emit('snap', frameOf(e)); } catch (err) { console.warn('[runner] snapshot failed', err); }
   }
 
+  /**
+   * Events of a step that is not rendered (hidden tab): the battle on screen keeps its state-bearing ones for the next
+   * rendered frame (keepsState, ≤ HELD_MAX — beyond that it is re-entered from the field meta); any other battle starts
+   * from its field meta when shown (show()), so its events go.
+   */
+  function hold(e) {
+    let ev = [];
+    try { ev = e.battle.drainEvents() || []; } catch { ev = []; }
+    if (e !== cur || e.stale) return;
+    for (const x of ev) if (keepsState(x)) e.held.push(x);
+    if (e.held.length > HELD_MAX) { e.held = []; e.stale = true; }
+  }
+
   function progress(e, force = false) {
     if (!e.authoritative || e.resultSent || !net) return;
     const t = now();
@@ -420,7 +449,7 @@ export function createBattleRunner(deps) {
     const dt = stepEntry(e, n);
     if (dt > stats.maxFrameMs) stats.maxFrameMs = dt;
     if (render) emitFrame(e, catchingUp);
-    else { try { e.battle.drainEvents(); } catch { /* ignore */ } }
+    else hold(e);
     noteLeaks(e);
     progress(e);
     if (e.battle.finished) finished(e);
@@ -456,6 +485,8 @@ export function createBattleRunner(deps) {
   /** Put an entry on screen: field meta into the store (the game screen enters it), then its current frame. */
   function show(e) {
     cur = e;
+    e.held = [];
+    e.stale = false;
     let meta = null;
     try { meta = e.battle.fieldMeta(); } catch { meta = { units: [] }; }
     const field = {
@@ -538,6 +569,9 @@ export function createBattleRunner(deps) {
       leaks: 0, leakMark: '', left: null,
       // live bond layers grown in this battle { [playerId]: { [bondId]: n } } and their total gain (noteLayers)
       live: null, layerSum: 0,
+      // state-bearing events of the steps run while the tab was hidden (hold(); delivered by the next rendered frame),
+      // and whether that backlog overflowed (the next frame re-enters the view from the field meta)
+      held: [], stale: false,
     };
     if (lastPool && battle.sharedBoss && typeof battle.sharedBoss.sync === 'function') {
       battle.sharedBoss.sync(lastPool.hp, lastPool.acked ? lastPool.acked[e.fieldId] : undefined);

public/js/render/app.js

@@ -21,8 +21,10 @@
 //                                               operators on the field under a redeploy ring and `elem` draws the
 //                                               element gauges (user playtest #4 items 8 / 9, render/units.js); a
 //                                               'die' with reason FORCED_EXIT (an operator entering 联防 knocked out,
-//                                               user playtest #5 item 2) goes straight to the held pose, no burst
-//   view.setLocalFeed({ on, speed })            frames come from the local sim every frame (client-side combat):
+//                                               user playtest #5 item 2) goes straight to the held pose, no burst; an
+//                                               fx with a `form` (shared/protocol.js fxForm) switches the enemy's
+//                                               model to that clip set (render/units.js FORMS)
+//   view.setLocalFeed({ on, speed })          frames come from the local sim every frame (client-side combat):
 //                                               ~2-frame buffer at the battle's game speed
 //   view.highlightTiles(tiles, style)           [[r,c]] | [{row,col}]; style 'legal'|'illegal'|'range'|'rangeStand'|
 //                                               'hover'|'target'|{color,fill,line,group}; highlightTiles(null) clears all
@@ -89,6 +91,7 @@
 // `data` is the client data store (public/js/data.js: lookup(file, id)) or plain { chess, tokens, items, enemies } maps.
 
 import { GEO, ANIM, UF } from '../../../shared/constants.js';
+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';
@@ -1430,24 +1433,25 @@ export async function createFieldView(host, options = {}) {
         break;
       }
       case 'status': { const v = views.get(e[1]); if (v) v.onStatus?.(e[2], !!e[3]); break; }
-      case 'fx':
+      case 'fx': {
         if (e[4] && typeof e[4] === 'object' && e[4].consumed && e[4].id != null) {
           consumedIds.add(e[4].id);
           if (consumedIds.size > 200) consumedIds.delete(consumedIds.values().next().value);
         }
-        // an enemy's mode change (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 — user report after 0.1.0): a 'phase' kind, or the `form` any other fx carries,
-        // switches the view's clip set (UnitView.setForm, a kind without a clip set of that skeleton changes nothing);
-        // the info keeps it for a view built later
-        const ex4 = e[4] && typeof e[4] === 'object' && e[4].id != null ? e[4] : null;
-        const form = !ex4 ? undefined : e[1] === 'phase' ? ex4.kind : 'form' in ex4 ? ex4.form : undefined;
+        // 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
+        // nothing); the info keeps it for a view built later. The client runner never drops these fx (catch-up frames,
+        // hidden-tab backlog), nor does the game screen's pre-entry buffer.
+        const form = fxForm(e);
         if (form !== undefined) {
-          const inf = infos.get(ex4.id);
-          if (inf && (typeof form !== 'string' || FORMS[inf.spine || inf.defId]?.[form])) inf.form = typeof form === 'string' ? form : null;
-          views.get(ex4.id)?.setForm?.(form, ex4);
+          const inf = infos.get(e[4].id);
+          if (inf && (form === null || FORMS[inf.spine || inf.defId]?.[form])) inf.form = form;
+          views.get(e[4].id)?.setForm?.(form, e[4]);
         }
         fx.simFx(e[1], Number(e[2]), Number(e[3]), e[4]);
         break;
+      }
       case 'layer': {
         const bondId = e[2], n = Number(e[3]) || 0;
         if (!(n > 0) || typeof bondId !== 'string') break;

public/js/render/units.js

@@ -109,7 +109,8 @@ export const EL_BAR = Object.freeze({ icon: 0.15, min: 8, max: 15, enemy: 0.8, g
  * - 转译基底·α (user report after 0.1.0, #5): its 2 s change clip A_Die_B / _C / _D, then 寻仇者 B_*, 幽灵 C_* (no attack
  *   clip: it never attacks) or 特战术师 D_* — its manifest roles are the original form's A_Idle / A_Move;
  * - 深池逐火战士 / 精锐战士 / 护卫 (#8): knocked out → 'Die' (the 1 s 重生), the 余烬 on Idle_2 / Move_2 and its death on
- *   Die_2; standing up again → 'Revive', then the warrior's manifest clips;
+ *   Die_2 (also while 'Revive' plays: the ember can still be beaten); standing up again → 'Revive', then the warrior's
+ *   manifest clips;
  * - 假想敌：再生: knocked out → A_Die, the 傀儡 on B_Idle / B_Move / B_Die; back → B_Revive, then the A_* manifest clips;
  *   (both: the stand-up clip (`end`) is timed from the 'ember' fx's `dur` to end as the husk stands up — the 'revive'
  *   fx then only lands in the manifest clips);
@@ -393,11 +394,11 @@ export class UnitView {
   }
 
   /**
-   * The unit changed mode (sim fx 'phase' { id, kind } or another fx's `form`; `fx` = that fx's extra): the mode's clip
+   * The unit changed mode (the `form` of a sim fx — shared/protocol.js fxForm; `fx` = that fx's extra): the mode's clip
    * set (FORMS) after its change clip, and its closing clip (`end`, landing in the `next` form's clips) timed to end
-   * `fx.dur` game s later; null goes back
-   * to the manifest clips; a kind this skeleton has no clip set for (an arts barrier, a broken charge …) changes
-   * nothing. Kept for a model built later.
+   * `fx.dur` game s later — the unit is still in this mode while it plays (an ember can be beaten in its last second),
+   * so this mode's death clip stays until the next mode's fx; null goes back to the manifest clips; a kind this skeleton
+   * has no clip set for (an arts barrier, a broken charge …) changes nothing. Kept for a model built later.
    */
   setForm(kind, fx = null) {
     const k = typeof kind === 'string' ? kind : null;
@@ -409,7 +410,8 @@ export class UnitView {
     const f = this._formSpec();
     if (!this.actor) return;
     const dur = fx && Number(fx.dur);
-    const next = f && f.next ? FORMS[this.info.spine || this.info.defId]?.[f.next]?.roles || null : null;
+    let next = f && f.next ? FORMS[this.info.spine || this.info.defId]?.[f.next]?.roles || null : null;
+    if (next && typeof f.roles.die === 'string') next = { ...next, die: f.roles.die };
     if (f) this.actor.setForm(f.roles, f.change || null, f.end && dur > 0 ? { clip: f.end, in: dur, roles: next } : null);
     else if (had) this.actor.setForm(null);
   }

public/js/screens/game.js

@@ -58,6 +58,7 @@
 
 import { useCallback, useEffect, useMemo, useRef, useState } from '../../vendor/hooks.module.js';
 import { PHASE, GEO } from '../../../shared/constants.js';
+import { fxForm } from '../../../shared/protocol.js';
 import { html, Spinner, PhaseBanner, Icon, Button, MicroLabel, confirmDialog, useTicker } from '../ui/components.js';
 import { useGameData, GIcon } from '../ui/gameComponents.js';
 import { useFieldView } from '../ui/fieldHost.js';
@@ -109,6 +110,9 @@ const SEL_RANGE = Object.freeze({ group: 'selRange', color: 0xff9c33, fill: 0.3,
 /** The tile an armed merge-completing card's elite will take (its own group; gold like the promotion cue, render/fx.js). */
 const MERGE_HL = Object.freeze({ group: 'mergeTile', color: 0xffd45a, fill: 0.34, line: 1 });
 const STATE_EV = new Set(['spawn', 'die', 'deploy', 'status', 'skill']);
+/** Event tuples replayed when a field is entered late: the state-bearing kinds and the fx that change an enemy's model
+ *  form (shared/protocol.js fxForm — the field meta's UnitInfo `form` predates them). */
+const keepEarly = (e) => Array.isArray(e) && (STATE_EV.has(e[0]) || fxForm(e) !== undefined);
 
 /** Router for the in-match screens. */
 export function GameScreen() {
@@ -446,7 +450,7 @@ function MatchScreen() {
         if (typeof msg.fieldId !== 'string') return;
         const buf = evBufRef.current.get(msg.fieldId) || [];
         // only state-bearing tuples are replayed later (see the enter effect)
-        for (const e of msg.ev) if (Array.isArray(e) && STATE_EV.has(e[0])) buf.push(e);
+        for (const e of msg.ev) if (keepEarly(e)) buf.push(e);
         if (buf.length > 1500) buf.splice(0, buf.length - 1500);
         evBufRef.current.set(msg.fieldId, buf);
         if (evBufRef.current.size > 8) evBufRef.current.delete(evBufRef.current.keys().next().value);