HUD ironing (task #38): authentic Lock producer + simple-X mode

- LOCK rules transcribed from the exported HudSimulation
  (part_013.c:5619-5634): lock requires a target AND your own HUD host
  zone damage < 0.75 (_DAT_004b7ec4 -- a shot-up targeting computer
  drops lock) AND the targeted zone damage < 1.0 (_DAT_004b7ec8;
  whole-mech target checks zone 0 -- a wreck's dead zone can't
  re-lock). Box and ring are now separate signals like the binary:
  gBTHudLockState 1 = target held (hotbox draws), 2 = LOCKED (+ the
  spinning ring).
- SIMPLE-X mode: the ctor's [0x99] minimal-reticle list transcribed
  (@4689-4705: green +-0.02..0.08 cross on the aim translate); Draw
  switches master <-> simple X on the PrimaryHudOn element bit (0x20),
  completing the recovered Execute's state-list logic.
- Canopy diagnosis sharpened (open-questions): blx_cop is the torso
  segment's inside-skeleton mesh enclosing the eye; the black box =
  the skeleton render branch missing its texture + PUNCH cutout (the
  canopy windows are punch texels). A rendering-branch task; stays
  hidden by default.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

context/gauges-hud.md

@@ -113,8 +113,15 @@ and every instrument is now live [T2]:**
   (the weapon-GROUP bits Front/Rear/Left/Right). **Range plays NO part** — Execute never reads
   the stored TargetWithinRange slots.
 - **Lock ring** = subB9 (ring+cross) at frame centre, **SPINNING 4°/frame** while the Lock attr
-  (0xA) is up (port: while a target is locked); the binary also hangs the PNAMEx.bgf player-name
-  mesh on the 3D marker here (3D chain still deferred).
+  (0xA) is up. The Lock PRODUCER is the authentic HudSimulation rule (part_013.c:5619-5634 [T1],
+  wired task #38): lock requires a target AND your own HUD's host zone damage < **0.75** (a
+  shot-up targeting computer loses lock) AND the targeted zone's damage < **1.0** (whole-mech
+  target checks zone 0 — so a wreck's dead zone can't re-lock). The hotbox stays visible without
+  lock (box = HotBoxVector, ring = Lock — separate signals). The binary also hangs the PNAMEx.bgf
+  player-name mesh on the 3D marker here (3D chain still deferred).
+- **Simple-X mode** (PrimaryHudOn off, mask 0x20): the minimal reticle — a small green cross
+  (±0.02..0.08 arms) riding the aim translate (ctor @4689-4705 [T1]) — swapped for the full HUD
+  by Draw's state switch.
 - **Target HOTBOX** (attr 0xB HotBoxVector) = a rectangle hugging the projected extents — x±4
   around the hotbox point, +1/−11.5 vertical (K=2.8145 baked projection; the port uses the live
   per-axis projection) — switching to the left/right edge ARROW past ±1.6 or behind.

context/open-questions.md

@@ -60,16 +60,18 @@ authentic path scoped.
   by the mouse — wire the real channel when pod hardware lands; (c) pre-burial, the pick still
   tests the sinking wreck's collision box at its parked position (pre-existing wreck-targeting
   behavior).
-- **Cockpit HUD leftovers (tasks #35-#37 residue, 2026-07-08)** — the reticle + 7 weapon pips +
+- **Cockpit HUD leftovers (tasks #35-#38 residue, 2026-07-08)** — the reticle + 7 weapon pips +
   ALL the instrument dynamics are LIVE (the Execute @004cdcf0 gap was RECOVERED via capstone
-  disasm, task #37 — see [[gauges-hud]] for the full instrument map). Remaining: (a) the
-  **blx_cop canopy shell** renders BLACK (untextured/unlit in our inside view) so it's hidden by a
-  name filter — `BT_INSIDE_COCKPIT=1` shows it; the authentic look needs its material/lighting
-  path; (b) the **3D marker chain** ([0x31c]/[0x320] dpl objects + the PNAME1-8.bgf player-name
-  meshes the Execute hangs over the locked target); (c) the "simple X" list [0x264]
-  (PrimaryHudOn off — the minimal reticle mode) is built empty in the port; (d) the HUD Lock
-  attr's (0xA) own HudSimulation producer (port analog: locked == designated) and the compass
-  rotation SIGN are [T3].
+  disasm, task #37; the authentic Lock producer + the simple-X mode landed in #38 — see
+  [[gauges-hud]] for the full instrument map). Remaining: (a) the **blx_cop canopy shell**: it is
+  the torso segment's SkeletonType_A mesh and fully encloses the eye; it renders as a black box
+  because the skeleton-branch render path isn't giving it its texture + the PUNCH cutout (the
+  canopy WINDOWS are punch texels — with punch live the black pane texels become holes and the
+  world shows through the frame). Fix lives in the [[rendering]] skeleton/punch branch, not the
+  HUD; hidden by name filter until then (`BT_INSIDE_COCKPIT=1` shows it). (b) the **3D marker
+  chain** ([0x31c]/[0x320] dpl objects + the PNAME1-8.bgf player-name meshes over the locked
+  target — matters for MP). (c) the compass rotation SIGN is derived-not-verified [T3] (turn
+  left → the stem should swing right; flip the sin sign in Draw if footage disagrees).
 - **StatusMessagePool (NULL stub, btstubs.cpp:62)** — the per-player status-message queue.
   BTPlayer+0x1dc is never populated → MessageBoard is empty (authentic for bring-up). What
   resolves it: wire the pool + decode `AddStatusMessage @0042e580` + the `Player__StatusMessage`