CydandClaude Fable 5
7c3d089d9c
Operator report: "artifacts bleeding over from the radar display into the
MFDs, I have noticed this in the BT411 builds as well, but does not happen
in the original."
MECHANISM (proven from the archive source, not inferred):
The ten cockpit heads are not ten framebuffers -- L4GAUGE.CFG gives each
port a BIT MASK into ONE 16-bit buffer. The colour head is six bits
(sec, 0x003F); the MFDs are bits 8-15 of the same words. A colour-head
defect can therefore only ever surface as MFD garbage, which is exactly
the reported shape.
The two translation-table builders in L4VB16.CPP are asymmetric:
BuildSecondaryTranslation (:5419) writes ONLY the active-bit
combinations -- 1<<numberOfBits entries, so 64 of int
translationTable[256] for this port. Entries 64..255 are never
written.
BuildAuxiliaryTranslation (:5443) nests IncrementInactive inside
IncrementActive and so fills all 256 -- which is why the mono MFD
ports are safe by construction and must NOT be touched.
DrawPixelMap8 (:2708) indexes that table with an 8-BIT source pixel, and
DrawPoint ORs the result in UNMASKED. An out-of-range index therefore
ORs whatever the heap left at translationTable[n] straight into other
ports' planes. The colour head's own art carries out-of-range
sentinels: AVACRIT.PCC is 94% <= 63 with 6% at exactly 231, BTSEC1.PCX
99.8% <= 63 with 0.2% at 254. Transparent draws skip them; OPAQUE draws
put every one through the table.
That it depends on heap CONTENTS rather than drawing logic explains both
the intermittency and why BT411 shows it too: both reconstructions
inherit the same latent read from the archive.
THE CHANGE, via the sanctioned source410-shadows-CODE seam (CODE/ is
untouched): a verbatim copy of CODE/RP/MUNGA_L4/L4GREND.CPP with one
difference -- port construction builds a BTL4GraphicsPort, whose ctor
zeroes translationTable[1<<numberOfBits .. 255] for SECONDARY ports only.
The guard (bit_mask & 0xFF) != 0 is literally the test
BuildSecondaryTranslation itself asserts on. numberOfBits is a popcount
set in the base ctor, so the subclass body sees 6 and the later
SetSecondaryPalette -> BuildSecondaryTranslation refills 0..63 over the
top without disturbing the zeroed tail.
WHAT IS AND IS NOT PROVEN -- the honest scoreboard:
PROVEN non-regressive. Gauge A/B, three boots: unfixed x2 and fixed x1
score identically on every head (Mfd1 132/0, Mfd2 37/7, Mfd3 23/0,
Eng1/2/3 and Comm exact), against a ~6px across-boot noise floor
established by re-booting the same binary.
NOT PROVEN to cure the symptom. The A/B rig captures the boot/attract
cockpit, where the MFD heads already show ZERO extra pixels -- there is
no bleed there to remove. The operator's report is in-mission with the
radar live. This is a hardening change against a real uninitialised
read that matches the symptom exactly; the cure needs a mission-state
capture to confirm.
METHOD NOTE: the first "fixed" capture appeared to regress the MFDs by
~2700px and nearly got the change reverted. It was a bad grab caught
mid-draw -- rebuild-and-rerun matched the unfixed numbers exactly. The
two-agreeing-runs rule earned its keep; a single run would have thrown
away a correct change. Worth noting the noise floor that mattered was
ACROSS boots, not the within-boot floor measured first.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
source410 — literal reconstruction of the missing BT 4.10 game source
Everything in this directory is RECONSTRUCTED, not recovered. The authentic surviving
source lives in CODE/ and is never mixed with this tree. The goal here is an
archival-grade recreation of the d:\tesla_bt\ translation units that exist only inside
BTL4OPT.EXE (the shipped 4.10 binary), written in the 1995 VWE house style against the
1995 MUNGA/MUNGA_L4 engine headers that DID survive.
Ground rules
- Never copy a reconstructed file into
CODE/— the assembled buildable tree (originals + reconstructions) is produced by a script into a build directory, so provenance stays unambiguous file-by-file. - Every
.CPPhere has a.NOTES.mdsidecar carrying the evidence: the binary address map, decomp references, which sibling sources supplied each idiom, and every judgment call with its tier ([T1] decomp-proven … [T4] style guess). The.CPPitself stays clean 1995 style — no modern annotations inside. - Assert line numbers are constraints. The binary's
Fail()sites record the original file+line (BTL4APP.CPP:400etc.); reconstructed files are shaped so those calls land on their recorded lines. A file that can't meet its line constraints yet says so in the sidecar. - Layout mirrors the original tree:
BT/(bt.lib, 36 TUs) andBT_L4/(btl4.lib, 13 TUs + BTL4.CPP), matching the survivingBT.MAK/BTL4.MAK.
What drives the work
- The per-TU manifest:
C:\VWE\BT411\reference\BT410_SOURCE_MANIFEST.md(tooltools/manifest410.py; method logphases/phase-03-bt410-source-manifest.md). - The decomp:
C:\VWE\BT411\reference\decomp\all\part_*.c(+section_dump.txtstrings). - The port's semantic reconstructions:
C:\VWE\BT411\game\reconstructed\(WinTesla-hosted; each literal file here re-hosts one back onto the 1995 engine APIs). - Style/idiom exemplars: surviving
CODE/BT/*.CPP,CODE/RP/RP_L4/*.CPP,CODE/RP/MUNGA*/**(the 1995 engine source itself).
Status (2026-07-19)
Compile verification is LIVE: ./compile410.sh --sweep (BC4.52 + the authentic OPT.MAK
flags; the period compiler is the reviewer). backdate.py mechanizes WinTesla→1995 header
back-dating (donors: C:\VWE\BT412\engine\MUNGA\*.h).
| item | state |
|---|---|
| THE WHOLE TREE COMPILES (2026-07-19) | ✅ 11/11: all 10 surviving originals + the BTL4APP.CPP pilot build clean under BC4.52 + authentic OPT flags (./compile410.sh --sweep) |
| BT/BTCNSL.HPP + BT/BTSCNRL.HPP | ✅ reconstructed — console wire IDs recovered from the binary (Killed=9, Damaged=10, ScoreUpdate=13, DeathWithoutHonor=15 [T1]; TeamScore=12 [T4 GUESS — verify]); see BTCNSL.NOTES.md |
| BT_L4/BTL4APP.CPP (pilot reconstruction) | ✅ compiles (18.5KB obj); 12/12 functions, Fail() at recorded line 400 |
| Staged header family (13: mech/mechsub/heat/powersub/mechweap/emitter/mechmppr/btplayer/projtile/missile + btl4mppr/btl4vid) | ✅ [T3] interface-proven by every surviving consumer; layouts parked in reserved[] blocks — see STAGED-HEADERS.NOTES.md + MECH-LAYOUT.md |
| MUNGA backfills (VDATA, ROTATION, VECTOR2D, AUDREND, APP, LAMP, GAUGREND, GAUGE) | ✅ compile-proven (BACKFILLS.NOTES.md) |
Next work package — the mech-family, REVISED (round-3 finding, 2026-07-19): the plan to "reconstruct mech.hpp first" was the wrong order. A full read of the port's mech.hpp shows it is a hybrid (1995 skeleton + Recon proxies + port-only members + relocated fields), and substantial regions of the binary's 0x854-byte Mech object remain UNMAPPED — the port declares "the remaining members up to sizeof==0x854" in its mech2-4 slices. A literal MECH.HPP that precedes those TU reconstructions would be fiction. Corrected order:
- MECH.HPP is the CAPSTONE, grown incrementally with each mech-family TU
reconstruction (mech.cpp → mech2-4 → subsystem TUs), starting as an interface +
known-ordered members with explicit
reserved[]filler for unmapped regions (sidecar-tracked), tightened as each TU pins its slice. - The dependent headers (
mechsub,mechmppr,btl4mppr,emitter+mechweap,btplayer,projtile,missile) ship WITH their TUs against the staged MECH.HPP. - The blocked originals (BTTOOL, GAUSS, PPC, BTREG) and the BTL4APP pilot compile green as those land — BTREG last (it includes the whole game-header world). Offset oracles for every stage: BT411 CLASSMAP.md, decomp-reference.md §3, and the port headers' static_assert-locked members.
Toolchain — IN HAND (2026-07-19)
Borland C++ 4.52, archived at ../../BORLAND/BC45/, chosen by byte-match: the fleet's own
CODE/RP/CW32.LIB is identical to 4.52's (and not 4.5's). BCC32/TLINK32/TLIB/MAKE run natively
on Win11. The shipped BTL4OPT.EXE recipe is CODE/BT/OPT.MAK (plain bcc32,
-DLBE4;DEBUG_LEVEL=0;DEBUG_STREAM=cout, -5 -a4 -ff -k- -V -Jg -x- -RT- + the full -O set,
PCH btopt.csm; link -Tpe -ax with c0x32.obj + dpmi32.lib + cw32.lib = Borland PowerPack
DPMI32, not Phar Lap TNT). Compile verification of reconstructed TUs is therefore possible
file-by-file; the current blocker for full closure is the 1995 engine header gap (vdata.hpp
first — only the drifted WinTesla VDATA.h survives, in BT412/engine). Include order for
builds: CODE/BT/* over CODE/RP/*, -DNO_PRECOMPILED_HEADERS until the mech-family headers
are reconstructed. Remaining gap: TASM32 (JOYSTICK.ASM only).
Link campaign (build410, 2026-07-19)
source410/build410.sh assembles BTL4OPT.EXE: merged-engine mass compile (152/152 green
— the ENTIRE surviving engine compiles), BT TUs (11/11), tlib libs (munga 1.25MB / mungal4
with the prebuilt-1995 objs / bt / btl4), then the authentic tlink32 link rooted by a probe
main (build scaffold). First true link run: 52 unresolved externals
(UNRESOLVED-LEDGER.txt) = the measured remaining gap. Kill-lists: l4gauge.cpp back-date
(14 widget statics), the missing-engine-body back-date wave (~24: rotation, player, team,
l4app, explode, dropzone, terrain, cultural, subsystm-statics, netclient...), the prebuilt
RANDOM.obj fold, and the staged game-TU statics blocks (MECH.CPP et al. — each TU file opens
with its binary-evidenced Derivation/SharedData statics and grows into the full body).
Link-lib arbitration: SOS = SOSDBXC+SOSMBXC (the 32-bit Borland-flat variants; SOSMW*=16-bit),
WATTCP excluded (it belongs to the 16-bit NetNub TSR — the game talks to it via shared
memory), filestrm = the RP-era pair (BT-tree pair is post-4.10 drift; override layer).