Stage modules (REL and PRS)

The data of a stage lives in a REL module (stgNND.rel for stages, boss_*D.rel for bosses) and, for Chao World, a PRS-wrapped REL (ChaoStg*.prs). A module is both the stage’s code and its data: it holds the stage’s landtables, its object list, and the names of the texture archives and light files it uses. Observed

Counts here are from a recorded census of the USA disc GSNE8P; they cannot be re-checked now. Observed

Loading a module

SA Tools’ game configuration lists each module’s file, its load address (key, for example C900000) and the offsets of its items (landtables, object list). Sourced · SA Tools A module is loaded as: decompress with PRS where the file is flagged, then with SaCompGC (the GameCube REL compression), then relocate with the REL fixups (SplitTools’ DecompressREL and FixRELPointers). Sourced · SA Tools After loading, pointers are absolute, and a file offset is pointer − key. Observed

PRS is a byte-oriented LZ77 compression used by the SEGA Ninja games on stage modules and on the GVM texture archives (.prs). Sourced · SA Tools

Census of the disc

Of the 79 stage data files with landtables (story stages, 2P stages, bosses and Chao World), all load: they hold 101 landtables and 27,919 COL entries, with 10,006 distinct attaches, and building them gave 0 errors. Observed

• 17,597 visible COL entries use Ginja (GameCube) models, and 1,482 visible entries use Chunk models (the landtables with format=SA2). Observed
• 8,816 invisible COL entries use Basic (collision) models, plus 24 that use Ginja models. Observed

The model formats and the COL structure are on Landtables and models. The stage ids are stg plus two digits (stg13 is City Escape), the data file name adds D; a stage may have more than one landtable, named by suffix (_uv, _poison, _light, _ani, _tani, _x). Observed

Strings of a module

A module carries its texture-archive names as strings (for example landtx03 and landtx03_suimen in stg03’s REL) and its light and fog file names (stg13_light.bin, stg13_fog.bin, stg24_fogA.bin in stg24D.rel), including some that are not on the disc (stg13_fog.bin). Observed How the game binds them is on Textures and Light and fog. The module also contains path records for the stage’s routes (Object placement). Observed

How does the game’s own loader walk a module?

Everything above follows SA Tools’ loader; the game’s code that binds a module’s data was not read.