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>
The reconstructed tree now produces a runnable binary with the authentic
1995 toolchain (BC4.52 / tlink32 / DPMI32):
- BTL4.CPP main TU reconstructed from the 4.11 Ghidra decomp (FUN_0040109c)
+ the 4.10 binary's own string pool + surviving RPL4TOOL.CPP house style;
probe_main.cpp scaffold retired (BTL4.NOTES.md documents every decoded call)
- L4NET.CPP staged: L4NetworkManager ctor/dtor + 10 vtable-pulled virtuals
(standalone-benign ones no-op, network ones Fail loudly) + NetNub client
globals (Net_Common_Ptr=NULL routes L4File to its plain-DOS path)
- build410.sh: libs now built in the AUTHENTIC makefile member order
(MUNGA.MAK / mungal4.mak / BT.MAK / BTL4.MAK). Order is load-bearing:
tlink emits static-init records in module pull order, and alphabetical
order booted into a null-vptr crash (IcomManager::ClassDerivations
constructing before parent NetworkClient::ClassDerivations). Also fixed
stage_link to the proven 32-bit lib set (SOSDBXC+SOSMBXC, no WATTCPLG)
- BOXTREE.HPP MemoryBlock unify, BTL4GRND notify stubs, remaining engine
backfills (audio/gauge/resource/stream TUs) that closed the deep ledger
Smoke test (DOSBox-X + 32RTM, copy of the pod BT tree, our exe swapped in):
BattleTech v4.10
BTL4Application::BTL4Application
l4net.cpp(22): L4NetworkManager -- l4net.cpp not yet reconstructed
Static init, main, -egg parse, BTL4.RES load (version 1.0.6 check passes),
ApplicationManager and the BTL4Application ctor chain all execute real
reconstructed code; boot halts at the first staged Fail() as designed.
Next brick: the real l4net.cpp body.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
The tlink32 campaign after the checkpoint: eleven engine bodies back-dated
from BT412 (rotation player team explode dropzone terrain cultural receiver
subsystm app l4gauge - the Application core included), the WinTesla-ectomy
handled by backdate.py's new unwrap rules (accessor-fn statics -> 1995 static
objects, decl rewrites, pointer->reference Derivation ctor, 2007 windowed-
gauge/console-marshal/idle-pump excisions), staged statics TUs opened for the
game classes (MECH/BTPLAYER/BTDIRECT/PROJTILE/MISSILE/BTL4MPPR .CPP + L4APP/
NETWORK engine statics).
State: every compiled symbol short of the shallow graph RESOLVED (the 52- and
17-symbol ledgers burned to zero); with 32stub.exe in place the linker reaches
full vtable closure and emits the deep ledger (~210 symbols, UNRESOLVED-
LEDGER.txt): remaining engine bodies (objstrm cstr gauge/gaugrend graphics
pixelmap palette resfile ray scnrole explosion-table), the DOS driver extern
layer (_SVGA*/_PCSerial*/_PCSPAK*/joystick/netnub/sosMIDI), the full L4App
body, and the real game-TU frontier (Mech::Make et al.). Recipe proven for
every category.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
CydandClaude Fable 5