LEGIE decomp

WIP matching decomp of LEGIE 2009.

• Borland Delphi 7 (Object Pascal)
• FMOD 3.75
• GLScene 1.0.0.0714
• legie.exe is packed with UPX; unpacked binary is legie_unpacked.exe
• Data files: legie.sud / demo.sub (custom PACK format)
  • TGA, JPEG, BMP textures
  • OGG audio (music, dialogue, SFX)
  • MD2, 3DS models (use Noesis; two models exceed 2k verts)
  • _prulet.txt cutscene scripts (debugging leftover)

1. Install Borland Delphi 7
2. On first run, open the IDE empty, then File -> Open glscene/Delphi7/GLScene7.dpk, then Compile -> Install
3. Install Python 3.x, then pip install -r requirements.txt
4. Place legie.sud and fmod.dll in bin/

src              Compilable project
raw_idr          Interactive Delphi Reconstructor output
analysis         Take a guess..
tools            Python tooling
bin              "playable" game
pak_extracted    Extracted game assets (see unpack_sud.py)
glscene          GLScene 1.0.0.0714 source
fmod-3.75        FMOD 3.75 API

This project uses a matching-decomp approach: write Pascal code that compiles to identical assembly as the original binary, verified function-by-function.

Check what needs work:

python tools/progress.py # show match status for all functions
python tools/annotate_funcs.py --missing # list functions not yet in source

Start with small functions (fewer instructions = easier to match).

python tools/asm_differ.py 00561B60 # by original address
python tools/asm_differ.py --list # see all functions with addresses

Or read the IDR output directly in raw_idr/Unit1.pas -- search for the address. Each function has its full x86 assembly inside {* *} comment blocks with IDR annotations for strings, global variables, and call targets.

Edit src/UnitX.pas. Add or replace the function body. Annotate it with the original address:

procedure MyFunction; { 00561B60 }
begin
  // decompiled code here
end;

The { XXXXXXXX } comment links the function to its original for diffing.

python tools/build.py --diff MyFunction   # compile + diff in one step
python tools/build.py                     # just compile
python tools/asm_differ.py MyFunction     # just diff (no recompile)

The differ shows a side-by-side comparison with color:

• Green (OK): instruction matches
• Yellow (OPS): mnemonic matches, operands differ
• Red (DIFF): mnemonic mismatch
• Cyan (REC+): extra instruction in recompiled (often alignment padding)

Fix discrepancies shown by the differ. Common issues:

• Wrong variable types (e.g., Byte vs Integer changes register size al vs eax)
• Wrong calling convention or parameter order
• Missing var parameter (pass-by-reference vs pass-by-value)
• Compiler generating different control flow for equivalent logic
• String literals at wrong addresses (check ordering in source)

python tools/progress.py --report    # full report, saves to analysis/
python tools/build.py --diff-all     # build + show all function status

# Re-extract original assembly (after updating raw_idr files)
python tools/extract_asm.py

# Unpack game data for reference
python tools/unpack_sud.py legie.sud pak_extracted

# Check which functions lack address annotations
python tools/annotate_funcs.py

# Generate function address mapping file
python tools/annotate_funcs.py --gen-map

This project is licensed under the MIT license.