re: ui — the RATC bundle header is the screen's element declaration table

u32 count at 0x14, then fixed 60-byte entries of [name | 4 flag words | pivotX |
pivotY | 0]. The table lists both .t32 sprites and .rat records, so it is the
screen's element list.

Verified: for all 7 .t32 entries in the tutorial pause bundle the declared pivot
is exactly half the decoded texture's dimensions, 7/7 with no mismatch. That also
settles what the pair at 0x50/0x54 of a .rat record is — a .rat simply opens with
one of these declarations.

The language split is visible inside one bundle: the English build's .t32
declarations carry correct English pivots while its .rat declarations carry
Japanese-derived ones, so the sprite table is regenerated per language and the
layout layer is inherited from the Japanese master.

Adds tools/re-capture/ratc_decls.py (parse the table, check pivots against the
decoded textures).

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

docs/re/structures/ui-rat-layout.md

@@ -19,13 +19,33 @@ The UI is **one pak per screen** — `GP_TITLE`, `GP_PAUSE_MENU`, `GP_READY_ROOM
 `GP_HANGAR_ARSENAL`.
 
 Inside a screen pak, each top-level [RATC](../INDEX.md) bundle is **one (context × language)
-build of that screen**, and its children come in pairs:
+build of that screen**. Its own header is the screen's **element declaration table**, and
+the elements themselves follow as children:
 
 | child | what it is |
 |---|---|
 | `<name>.t32` | the sprite ([T8aD](texture-color-k8888.md)) |
 | `<name>.rat` | that sprite's **layout record** (this document) |
-| `<screen>loop1.rat` | a screen-level record (larger; not yet decoded) |
+| `<screen>loop1.rat` | a looping sprite animation (see below) |
+
+### The bundle header — element declaration table
+
+```
+0x14  u32   entry count
+0x20  entry[count], 60 bytes each:
+        +0   char[28]  element name, NUL-padded ("pgp_ttrl_eff10.t32", "pgp_ttrl_btn10.rat")
+        +28  u32 ×4    flags (0xffffffff / 0xffffffff / 0 / 0xffffffff on every entry seen)
+        +48  u32       pivot X
+        +52  u32       pivot Y
+        +56  u32       0
+```
+
+The table lists **both** sprites and `.rat` records — it is the screen's element list.
+`pgp_ttrl` declares 11: six `eff*`, `msg`, and four `.rat`s (`title`, `btn10..12`).
+
+✅ **Verified:** for all 7 `.t32` entries the declared pivot is *exactly* half the decoded
+texture's dimensions — `eff10` 408×120 → 204,60; `eff21` 428×360 → 214,180; `msg` 381×38 →
+190,19; and so on, 7/7 with no mismatch (`tools/re-capture/ratc_decls.py`).
 
 `GP_PAUSE_MENU.pak`'s six bundles are `{in-mission, tutorial} × {English, Japanese}`, with
 the two in-mission builds each present twice at identical size. The purpose of that
@@ -88,6 +108,11 @@ authored once and only the `.t32` sprites are swapped, which has two consequence
 - The baked pivot belongs to *whichever build the record was authored from*, not to the
   sprite actually shipped beside it. That is why `pgpbtn01`'s pivot (113 → a 226 px wide
   texture) matches neither the English sprite (207) nor the Japanese one (148).
+- The split is visible inside a single bundle: in the **English** tutorial build, every
+  `.t32` declaration carries the correct English pivot (7/7), while the `.rat` declarations
+  carry Japanese-derived ones (`btn10` → 43,21 = 86/2, the *Japanese* sprite). So the
+  `.t32` table is regenerated per language and the `.rat` layer is inherited from the
+  Japanese master.
 - **Do not infer anything about a language from a texture size** — see the traps below.
 
 ## Evidence

tools/re-capture/ratc_decls.py

@@ -0,0 +1,41 @@
+#!/usr/bin/env python3
+"""Parse a RATC bundle's header SPRITE DECLARATION TABLE: u32 count at 0x14, then
+fixed 60-byte entries of [name, NUL-padded | 4 u32 flags | pivotX | pivotY | 0].
+Check each pivot against half the decoded texture's real dimensions."""
+import struct, sys, glob, re, os
+
+def decls(d):
+    n = struct.unpack_from(">I", d, 0x14)[0]
+    out = []
+    for i in range(n):
+        o = 0x20 + i * 60
+        if o + 60 > len(d): break
+        name = d[o:o+28].split(b"\0")[0].decode("ascii", "replace")
+        px, py = struct.unpack_from(">II", d, o + 48)
+        out.append((name, px, py))
+    return n, out
+
+def texmap(prefix):
+    t = {}
+    for f in glob.glob(f"pause-tex/{prefix}_*.png"):
+        m = re.match(rf".*/{prefix}_(.+)\.t32_(\d+)x(\d+)\.png", f)
+        if m: t[m.group(1) + ".t32"] = (int(m.group(2)), int(m.group(3)))
+    return t
+
+for path, prefix in [(sys.argv[1], sys.argv[2])]:
+    d = open(path, "rb").read()
+    n, ds = decls(d)
+    tm = texmap(prefix)
+    print(f"{os.path.basename(path)}: count={n}, parsed={len(ds)}")
+    ok = bad = miss = 0
+    for name, px, py in ds:
+        if name in tm:
+            w, h = tm[name]
+            hit = (px == w // 2 and py == h // 2)
+            ok, bad = ok + hit, bad + (not hit)
+            flag = "OK " if hit else "MISMATCH"
+            print(f"  {flag} {name:28s} tex {w:4d}x{h:<4d} half {w//2:4d},{h//2:<4d} decl {px:4d},{py:<4d}")
+        else:
+            miss += 1
+            print(f"  ?   {name:28s} (no decoded texture) decl {px:4d},{py:<4d}")
+    print(f"  => pivot == half(texture): {ok} ok, {bad} mismatch, {miss} unchecked")