Entry 11

Models: the MOD format, all 6286 parsed, drawn in the viewer

2026-10-145mformatrenderdecomp

Filescrates/rugrats-data/src/model.rscrates/rugrats-render/src/models.rscrates/rugrats-viewer/src/main.rs

A database's models are its MOD file: 0xc0de0001, a count, a table of offsets (the high 11 bits of each are the model's own index), and models with a 32-byte header pointing at vertices (8 bytes: s16 x, y, z, w), a colour palette, and face sections. The face sections are the GPU's own primitive codes, which the hand-written model renderer (0x80010000) switches on: F3, F4, G3, G4 records are 12 bytes (a flags word, four vertex indices, then an RGB and the code for flat faces or four palette indices for gouraud), FT3, FT4, GT3, GT4 are 24 (the same, then u0 v0 CLUT, u1 v1 page, u2 v2 u3 v3).

Getting there took three passes of a Python sweep over all 31 MOD files. Textured records at 16 bytes derailed at the first FT3; at 24 for triangles and 28 for quads, 816 of 6286 models still failed, on FT4; the fourth texel pair shares the last word with the third, so every textured kind is 24 and all 6286 parse to their last byte. every_model_parses holds the Rust reader to that.

rugrats-viewer DB --models lays a database's models out in rows. DB22's are the cast in pieces (hands, shirts, legs, Grandpa's head and glasses) and the house's furniture, coloured and textured: character textures come from CHARACTR.RAW, which main loads to VRAM (576, 256), 384 x 256, beside the database's own A.RAW. The format page is docs/formats/mod.md.