A defect in the Phase 1 extractor, found by reading the data extent's contents:
level extents are declared in sector counts, the generic G/ pair table uses byte
counts, and level containers were being routed through the generic path. So
LEVEL0.WAD's data extent -- 6,484 sectors -- was taken as 6,484 bytes. Every
test still passed, because a truncated file is still a file.
The extent's own header gave it away: it declares an uncompressed total of
13,277,920 bytes, and 13,277,920 / 6,484 is 2047.7. A ratio landing on 2048 is
a unit error, not a compression ratio. Across 27 levels this had been discarding
roughly 300 MB of level content.
Level containers now go through the typed LevelHeader instead. Level 0 yields:
data.bin 13,279,232 the data extent
core_data.wad 9,738,678 the geometry, compressed
core_data.bin 16,969,296 the geometry, decompressed
core_index.bin 31,600 the geometry directory
gameplay.bin 659,456
sound_bank.bin 1,503,232
core_data is a WAD LZ77 stream -- the format already implemented for the game --
and it decompresses cleanly. The first real level content this project has
recovered.
New: LevelDataHeader parses the data extent's own header, a table of byte ranges
naming the level overlay executable, the geometry directory, the GS RAM image,
the HUD banks and the geometry. Note this is a third meaning for a "size" field
on the same disc, after sector counts in the level header and byte counts in the
generic table; all three are documented together in level-data.md so the next
parser does not rediscover this the hard way.
The geometry directory's offsets were checked against the geometry rather than
taken on trust: all twelve land inside the 16.9 MB of decompressed core_data,
which is what confirms the header is being read correctly. The class tables
themselves do not yet decode under the documented layout, and that is recorded
as open work in plan/level-assets.md rather than papered over.
75 unit tests, 9 integration tests against the real disc. Hash table regenerated
at 5,159 files and 5,671,915,799 bytes -- hashes only, no content. Extraction
now writes to ~/Documents/gc-extracted rather than /tmp, which is 16 GB and did
not have room for a 5.3 GB output.
