Static external-part placement (ship::assemble_ship) is only approximate — a GN_*
frame is the mount pivot, and the real offset lives in a runtime detail rig. So
capture ground truth from Canary instead.
Finding: the guest vertex buffer holds LOCAL coords (byte-identical to the .xpr),
so capital-ship parts are placed entirely in the vertex shader. The per-part
transform is in the VS float constants — c0..c2 are the WorldViewProjection rows;
normalising each by its norm (= projection x/y/z scales, sy/sx = 16:9) yields the
rigid WorldView (rows orthonormal, det +1). Expressing every part relative to a
reference part cancels the camera: rel_p = WV_ref⁻¹·WV_p, a pure ship-space rigid
transform.
- examples/correlate_capture.rs: parse xenia_ship_capture.log, decode the ship's
parts, match by vertex count, recover each part's ship-relative placement.
- docs/re/ship-placement-runtime-capture.md: full method + the capture protocol
(Canary branch capture-ship-placement, F10 hotkey) + validated e106 result.
Validated on e106 (ADAN Destroyer, Stage_S01): all 7 drawn parts matched by
vertex count; bdy_01/bdy_02 recovered as a PORT/STARBOARD pair (X = ∓264) that
static had overlapping; engines correctly aft; extent 872×670×2181. Only brg_01
(bridge) missing — culled at that camera angle, needs a bridge-facing capture.
HANDOFF: next = re-capture bridge, bake a per-ship placement table the viewer
prefers over assemble_ship, then capture the cruiser / ACROPOLIS / TCAF ships.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Stage containers (hidden/resource3d/Stage_S*.xpr) are collections of up to
~450 enemy/prop sub-models, not single meshes. Xbg7Model::stage_models decodes
them: each resource is a [12-byte header][index buffer][vertex buffer] block
(index count = descriptor marker, vertex count = u32 32 bytes before it) whose
on-disc offset is NOT stored, so it is located by content — one O(file) pass per
stride finds vertex-buffer starts (unit NORMAL at +12 whose previous slot isn't)
and each resource is pinned to the candidate whose indices validate and produce
non-degenerate, well-connected triangles. A connectivity gate (mean triangle
edge <= 0.28x the bbox diagonal) rejects spiky mis-anchors. ~4993 sub-models
decode across the 22 stages.
The same insight fixes the weapon single-model layout: it is [12-byte header]
[index][vertex] too, not [index][12-byte gap][vertex]. Reading indices from the
block start turned the 12 header bytes into 6 junk indices (2 leading degenerate
triangles — the recurring stray-triangle artifact) and dropped the last 6 real
indices. Skipping the header leaves vertex offsets identical (coverage unchanged
at 36/166) and corrects the triangle list. Verified on wep_00/03/04.
Adds `sylpheed-cli mesh {info,render}` — a headless software rasterizer that
writes a shaded PNG (orthographic, z-buffered, two-sided), so recovered geometry
can be verified without the GUI. Stages render as a normalised thumbnail grid;
--only filters sub-models.
Tests: stage_models_{decode,sweep,quality_audit}; docs/re updated (xbg7-mesh.md
evidence log + INDEX.md).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Dynamic-RE follow-up: capture Canary's GPU vertex-fetch + draw calls and
feed the ground truth back into the static decoder.
The GPU capture confirmed the reverse-engineered layout exactly — meshes
draw as triangle LISTs (prim=4) with pos f32x3 @0, normal f16x4 @0x0C,
uv f16x2 @0x14 — and revealed the XBG7 vertex format is NOT fixed-stride:
models omit elements (stride 20 = pos+normal, no UV; 24 = pos+normal+uv).
- mesh.rs: parse the descriptor's vertex declaration ({offset, format-code,
usage} triples; 0x2A23B9=pos f32x3, 0x1A2360=normal f16x4, 0x2C235F=uv
f16x2) to drive per-model stride + element offsets, instead of assuming
stride 24. Coverage 25 -> 36 fully-validated models (e.g. the Stage_S*
props, which are pos+normal only). Same index-range + unit-normal safety
gates; complex/mismatched layouts still declined.
- Endianness note (documented): the capture's fetch endian=k8in32 describes
the GPU's guest-memory copy, NOT the .xpr file bytes — reading the file
with k8in32 breaks the normals (|n|->1.33); naive big-endian per element
is correct (the game rearranges vertex data on load).
- tests: a coverage-regression test (>=35 models) + the existing weapon /
body-declined disc tests still pass.
Confirmed against a Canary draw-log capture; see docs/re/structures/
xbg7-mesh.md (evidence log + declaration table).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Reverse-engineer the single-stream XBG7 geometry layout (clean-room: hex
inspection + geometric validation of the retail disc's
hidden/resource3d/*.xpr, no game code copied) and present models as
textured 3D meshes in the explorer.
Format (docs/re/structures/xbg7-mesh.md): XBG7 geometry resources sit
inside XPR2 containers alongside TX2D textures. For ~25 single-stream
models (weapons, simple props) the data section is a sequence of
sub-meshes, each an u16-BE triangle-list index buffer followed (after a
fixed 12-byte header) by a stride-24 vertex buffer whose declaration is
in the descriptor: POSITION f32x3 @0x00, NORMAL f16x4 @0x0C, TEXCOORD
f16x2 @0x14. Sub-mesh (vtx,idx) counts come from descriptor tuples.
The +12 vertex offset is pinned by the recovered normals being exactly
unit-length (align16 lands 4 bytes early and silently corrupts every
field). A safety gate rejects any model whose indices are out of range
or whose mean |normal| is not ~1, declining garbage (Stage_S*
placeholders, the complex multi-stream hero-ship body) rather than
mis-decoding it.
- mesh.rs: Xbg7Model::from_xpr2 -> GameMesh { positions, normals, uvs,
indices }; standalone f16->f32; unit + real-disc tests (weapon decodes
to 215v/364t with unit normals + in-range UVs; DeltaSaber body
declined).
- texture.rs: from_xpr2_index / texture_names so the viewer can pick a
model's _col albedo map.
- viewer: loose .xpr with decodable XBG7 spawns Bevy meshes (real normals,
double-sided) textured with the albedo, framed by the orbit camera; the
central egui panel goes transparent so the 3D scene shows through.
Complex multi-stream body meshes (DeltaSaber f004, other vertex layouts)
remain undecoded and are cleanly declined — next target is dynamic RE.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Resolved the "colours look odd" channel-order/sRGB question for k_8_8_8_8
(T8aD 2D UI textures) with no emulator run:
- sRGB: Canary's Vulkan host-format table maps plain k_8_8_8_8 to
R8G8B8A8_UNORM and contains no R8G8B8A8_SRGB anywhere — gamma is a
separate explicit EDRAM path. So these are raw linear bytes; apply no
sRGB/gamma decode.
- Channel order: measured 789 real disc textures — byte0 is the opaque
alpha (==0xFF-dominant) in 97% — so on-disk is ARGB. Cross-checked
against xenia-rs decode_k8888_tiled, the Canary-validated M1/M2 path,
which nets the same [A,R,G,B]->[R,G,B,A]. sylpheed-formats is correct.
Promotes the k8888 entry HYPOTHESIS -> CONFIRMED; INDEX updated. XPR2
skybox tiling + viewer display-gamma remain separate open items.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Establish docs/re/ as the spec-side of the clean-room:
- README: confidence tiers (HYPOTHESIS/PROBABLE/CONFIRMED), promotion
requires NEW independent evidence, append-only evidence logs,
demote-on-contradiction, and a clean-room firewall (describe behaviour +
cite addresses; never paste decompiled code). Documents the toolchain
(sylpheed.db + zq.py, xenia-rs probes, Wine-Canary oracle) and the
join-by-guest-PC method with the VA-equality caveat.
- Function/structure templates + a seeded INDEX (9 already-reversed formats).
- First entry: texture-color-k8888 — CONFIRMED plain k_8_8_8_8 is linear
UNORM (no sRGB), channel order still to be measured.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
