Scene-prefixed asset bundles Confirmed

At a glance

Where

The PROT entries every CDNAME scene block seats: [.MAP][.PCH trigger sidecar][prescript][asset bundle] for towns; battle stages as bare-TMD streams; BGM as VAB streams

Magic

None shared - each shape is told apart by the content at +4 (Legaia TMD 0x80000002, VABp, a descriptor count, a u16 record count)

Parser

legaia_asset::{scene_tmd_stream, scene_vab_stream, scene_v12_table, scene_asset_table, scene_event_scripts}; categorize runs the detectors in order

Confidence

Confirmed - each walker is read off its retail consumer; corpus tiling asserted by disc-gated tests

Used by

Asset loader, Battle scene, Field scene viewer

scene_tmd_stream - bare-TMD prefix

The battle-stage layout: a 3D mesh up front, textures behind it. TMD is the PlayStation's model format (Legaia's own variant, see tmd); TIM is its texture format. The battle loader's custom walker reads it - not the standard streaming dispatcher, even though the chunk-header packing is identical.

An entry holds exactly one stream: the walker returns past the terminator and its single caller (battle init) calls it once. The type-0x01 meaning differs from the standard dispatcher, where 0x01 is a TIM list - the crash trap in the lede. The engine's field loader uses battle_tim_chunks to skip these battle-only TIMs; the row-479 NPC palettes are not field-resident, matching retail.

The leading TMD is a half shell, drawn twice

Rendered raw, one of these meshes looks like half a bowl - sky dome, mountain ring and far ground cut along a plane through the origin. That is what the entry authors: battle init registers the TMD once but links two background actors to it, the second under a per-stage transform that closes the circle. Object 0 is the shell; object 1 never draws. In all 182 entries the open side is -X (129), -Z (49) or +X (4) - never +Z, where the party sits. Placement lives in legaia_asset::battle_backdrop (battle); scene_tmd_stream::shell_shape returns the object-0 box plus its open side.

use legaia_asset::scene_tmd_stream;
if let Some(s) = scene_tmd_stream::detect(&buf) {
    let tmd = legaia_tmd::parse(&buf[s.tmd_range()])?;  // bare TMD, no wrapper
    for chunk in &s.tail_chunks { /* (type, size, payload) */ }
}
for c in scene_tmd_stream::battle_tim_chunks(&buf) {
    // c.payload_offset = inner PSX TIM magic offset; c.source is Tail for every retail entry
}

scene_vab_stream - VAB-prefix

Same outer wrapper, but the leading chunk is a Sony VAB (a sound bank: instrument programs plus sample data) and the tail chunks are standard DATA_FIELD chunks - usually the SEQ that plays on the bank. The single largest VAB carrier on the disc, about 17% of all entries.

Carriers: 119 of the 123 entries in the CDNAME vab_01 cluster, 53 in sound_data2, 19 in music_01, 14 across monster_data / battle_data, plus scattered hits. Read with scene_vab_stream::detect then legaia_vab::parse_header(buf, s.vab_range().start).

scene_v12_table - the .PCH walk-on trigger sidecar

When you step onto a doorway tile, something has to know that tile is special. This one-sector entry is that table: a four-kind sub-table directory whose only populated kind holds the scene's walk-on trigger records. One per scene, 97 on the disc; full field semantics on scene-v12-table.

The three tied words (N = 4 * param + 22) make the detector exact: 97 hits, zero false positives. The scene's real field-VM scripts are not here - they live in the scene MAN (script VM).

scene_asset_table - the town / dungeon bundle

The bundle the field loader reads when entering a scene: a count-prefixed descriptor table, then one LZS-compressed payload per descriptor (LZS is Legaia's compression, see lzs).

Slot i is the i-th descriptor; there is no separate indirection table. The runtime walker reads count, then dispatches each payload by type_size >> 24 (chain pinned under asset loader). The seven canonical kinds: TimList (textures), Tmd (meshes), Man (the scene's map data - encounter tables, actor placements, field scripts), Mes (dialog), Move (animation programs), Anm, Vdf.

The mesh pool is the descriptor walk

The Tmd descriptor is an asset::pack of every static mesh in the scene (town01: 121 meshes). The runtime mesh pool gains one slot per pack member, in pack order, after the five resident party / save-point meshes - Rim Elm is 5 + 114 = 119 slots. Placement of those meshes comes from the field map object table (field locomotion). A byte sweep for TMD magic is not a substitute: a scene block's bytes carry meshes the walk never registers. Parser scene_asset_table::mesh_pool.

scene_scripted_asset_table - a shape retail does not have

A composite pairing a prescript at offset 0 with a 7-asset table at the next sector boundary. It matches no retail entry: the real layout seats the prescript and the bundle as separate entries. The detector stays, pinned at zero matches by extract/tests/validation_suite.rs, so a reader regression fails a test instead of resurrecting the phantom.

tmd_size_prefix - truncated TMD-prefix

Sister of scene_tmd_stream for the truncated case: same header, but the claimed total size is larger than the on-disc payload. All object pointers fall inside the claimed size, so the file is a genuine prefix of a larger resource, not a broken header. 34 entries, all 12 KB (6 sectors), 2 or 4 objects each.

Confidence: the shape is Confirmed, the consumer Unknown - the loader probably allocates total_size and either zero-fills the tail or streams the rest from another entry.

scene_event_scripts - the prescript

The entry a scene block seats between its .PCH sidecar and its bundle: a [u16 count][u16 offsets[count]] table whose records stage the scene's ambient props - a swaying sign, a spinning windmill - for the move VM. 101 entries, 100 of them at slot 2 of a CDNAME block.

These records are not field-VM bytecode, however natural that looks. They are the per-scene sibling of the per-summon stagers (legaia_asset::summon_overlay): same record format, same consumer. Record 0 on towns is the scene's master ambient stager - a fixed 768-byte run of 8-byte spawn rows. The scene's field-VM scripts live in the MAN.

The runtime chain: a MAN script installs a record by id through the stager installer, which reads base + 2 + id*2 from the bundle relocated to RAM; the part-stager attaches it to an actor; the move VM runs record + 4 each frame. Walking every scene MAN for the install op shows this is the bundle's only consumer: partition-1 effect actors install record 0 on entry, partition-2 cutscene timelines install per-shot ids.

How we know

Dumps: ghidra/scripts/funcs/<addr>.txt. Source of record: docs/formats/scene-bundles.md.

See also