arcattackandClaude Opus 4.8
7b7d465e5e
Clean, self-contained extraction of the BattleTech-specific work from the
reverse-engineering workspace -- engine + game + content + build, with nothing
from Red Planet or the raw archive dumps. Builds green (Win32) and runs the
single-player drive->animate->target->fire->damage->destroy loop out of the box.
Layout:
engine/ MUNGA + MUNGA_L4 shared 2007 engine, carrying our BT render/loader
work (bgfload/L4D3D/L4VIDEO: BSL bit-slice decode, LOD/ground/shadow
models) + image codec; the minimal rp/ headers the audio HAL needs
game/ reconstructed BT logic + surviving-original BT source + fwd shims
+ WinMain launcher
content/ full runtime tree (BTL4.RES, VIDEO/, GAUGE/, AUDIO/, eggs, BTDPL.INI)
docs/ format specs + reconstruction ledgers
reference/ raw Ghidra pseudocode (recon source-of-truth) + decomp exporter
tools/ MP console emulator + map/resource scanners
One top-level CMake builds munga_engine lib + bt410_l4 game lib + btl4.exe.
All paths relativized (186 fwd shims + ~437 CMake abs paths -> repo-relative);
DXSDK is the one external, overridable via -DDXSDK. Verified: builds to a
byte-identical 2.27MB exe and runs combat (TARGET DESTROYED, 0 crashes) against
the bundled content.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
107 lines
5.2 KiB
Markdown
107 lines
5.2 KiB
Markdown
# BattleTech 4.11 (bt411)
|
||
|
||
A standalone Windows port of **Virtual World Entertainment's arcade *BattleTech*** (Tesla
|
||
platform, release 4.10, ~1995–96), reconstructed on the shared **RP411 Windows engine**. The
|
||
game boots, renders, and runs a single-player **drive → animate → target → fire → damage →
|
||
destroy** loop across all 8 maps, with two-instance multiplayer entity replication working.
|
||
|
||
This repo is a clean, self-contained extraction of the BattleTech-specific work from the larger
|
||
reverse-engineering workspace — engine + game + content + build, with nothing from Red Planet or
|
||
the raw archive dumps. It builds and runs out of the box.
|
||
|
||
> **License:** the game content (`content/`) and the original binary are proprietary to Virtual
|
||
> World / the pod owner. This repository is **private**; do not redistribute.
|
||
|
||
---
|
||
|
||
## Layout
|
||
|
||
```
|
||
CMakeLists.txt one build: munga_engine lib + bt410_l4 game lib + btl4.exe
|
||
engine/
|
||
MUNGA/ shared 2007 sim/render engine (149 .cpp + headers)
|
||
MUNGA_L4/ Win32/D3D9 HAL + renderer + asset loaders (43 .cpp), incl.
|
||
our BT work: bgfload / L4D3D / L4VIDEO + the image codec
|
||
shim/ minimal ATL shim (USES_CONVERSION/W2A)
|
||
lib/ OpenAL32 / libsndfile import libs + runtime DLLs
|
||
game/
|
||
reconstructed/ the reconstructed BT game logic (mech, subsystems, HUD, app)
|
||
original/BT,BT_L4 surviving original BT source + all BT headers
|
||
fwd/ header shims forwarding <NAME.hpp> -> the engine's NAME.h
|
||
btl4main.cpp WinMain launcher / entry point
|
||
content/ runtime data: BTL4.RES, VIDEO/, GAUGE/, AUDIO/, *.EGG, BTDPL.INI
|
||
docs/ format specs (BGF, assets) + reconstruction ledgers
|
||
reference/
|
||
decomp/ raw Ghidra pseudocode — source-of-truth for ongoing recon
|
||
ghidra_scripts/ the headless decomp exporter
|
||
tools/ btconsole.py (MP console emulator), map/resource scanners
|
||
run/ run.cmd helper
|
||
CLAUDE.md full project context / progressive knowledge base
|
||
```
|
||
|
||
## Prerequisites
|
||
|
||
- **Visual Studio 2019 BuildTools** (MSVC v142, x86). The Community install on the original dev
|
||
box was broken, hence the explicit BuildTools instance in the configure line below; adjust to
|
||
your install.
|
||
- **CMake ≥ 3.20**.
|
||
- **Legacy DirectX SDK (June 2010)** — the engine uses `d3dx9`/`dinput`/`dxerr`, removed from the
|
||
modern Windows SDK. Default path `C:/Program Files (x86)/Microsoft DirectX SDK (June 2010)`;
|
||
override with `-DDXSDK=<path>`. (The installer may throw a harmless **S1023** error — dismiss it;
|
||
the SDK headers/libs install before the failing redist step.)
|
||
|
||
OpenAL/libsndfile import libs + DLLs are vendored under `engine/lib/`; the DLLs are copied next to
|
||
the exe automatically at build time.
|
||
|
||
## Build (32-bit / Win32)
|
||
|
||
```
|
||
cmake -S . -B build -G "Visual Studio 16 2019" -A Win32 ^
|
||
-DCMAKE_GENERATOR_INSTANCE="C:/Program Files (x86)/Microsoft Visual Studio/2019/BuildTools"
|
||
cmake --build build --config Debug
|
||
```
|
||
|
||
Must be **Win32** — the DirectX SDK link libs are `Lib/x86`. The link uses `/FORCE`: the 1995
|
||
headers define free functions/globals without `inline`/`extern`, so identical symbols appear in
|
||
many translation units (~124 `LNK2005`); `/FORCE:MULTIPLE` keeps the first. `UNRESOLVED` tolerates
|
||
a dead offline-tool factory in `mech3.cpp` that is never called at runtime. (Cleanup task: move
|
||
those definitions to single TUs + neutralize the dead factory, then drop `/FORCE`.)
|
||
|
||
## Run
|
||
|
||
```
|
||
run\run.cmd REM boots DEV.EGG (grass / day)
|
||
run\run.cmd DBASE.EGG REM any egg in content/
|
||
```
|
||
|
||
The working directory **must** be `content/` (the engine resolves `BTL4.RES`, `VIDEO\`,
|
||
`BTDPL.INI`, and eggs relative to cwd); `run.cmd` handles that. Maps available in `BTL4.RES`:
|
||
`cavern grass rav polar3 polar4 arena1 arena2 dbase` — switch via a copied egg's `map=` field.
|
||
|
||
### Useful env-var flags (default OFF unless noted)
|
||
|
||
The authentic stack (gait, collision, real controls) is **default-on**; set `=0` to fall back.
|
||
Debug/harness flags: `BT_FORCE_THROTTLE=1` (auto-walk), `BT_SPAWN_ENEMY=1` (spawn a target dummy),
|
||
`BT_FORCE_FIRE=1` (auto-fire), `BT_HEAPCHECK=1` (whole-heap validation — slow), `BT_BSL=0` (legacy
|
||
texture decode), `BT_LOG=<file>`. Interactive: **WASD** drive, **Space/Ctrl** fire, **X** all-stop.
|
||
See `CLAUDE.md` for the complete list and the reconstruction history.
|
||
|
||
## Multiplayer (two instances, one box)
|
||
|
||
```
|
||
instance A: btl4.exe -egg MP.EGG -net 1501 (BT_LOG=mp_a.log)
|
||
instance B: btl4.exe -net 1601 (BT_LOG=mp_b.log)
|
||
console: python tools/btconsole.py MP.EGG 127.0.0.1:1501 127.0.0.1:1601
|
||
```
|
||
|
||
`-net <port>` enables networked mode; the console emulator delivers the mission egg and the launch
|
||
command. Entity + movement replication works; cross-pod combat is in progress.
|
||
|
||
## Status & continuing the work
|
||
|
||
The engine, renderer, audio, HAL, build, locomotion, collision, damage, and render fidelity are
|
||
done; per-subsystem reconstruction (gyro integrator, projectile/missile weapons) and MP combat are
|
||
the active fronts. `docs/` holds the format specs and reconstruction ledgers; `reference/decomp/`
|
||
holds the raw pseudocode that every reconstruction is verified against. `CLAUDE.md` is the durable,
|
||
progressive project context — read it first.
|