Files
Going-Commando/crates/gc-extract/tests/disc.rs
T
ReaperOfVeriod 79025b22d6 Decode the tie class header prefix that RAC1 and RAC2 agree on
Tie is the easy one of the three geometry subsystems -- instanced
static props, no skeleton -- so it is the right place to start.

RAC1's class header is 0x80 bytes. RAC2 agrees with it over the first
0x48 and diverges after. From 0x48 the RAC1 layout does not describe
RAC2 data: lod_info at 0x50 reads back as noise, packet_count and
texture_count are zero on every class examined, and the normals offset
at 0x0c points 117,788,434 bytes into a 16.9 MB lump.

Only the agreed-on prefix is decoded. What makes it trustworthy:

* o_class at 0x44 equals the core index's class number for all 1,864 tie
  classes across all 27 levels. A field landing on the right number that
  often is not a coincidence, and it pins the header base.
* The LOD distances are ordered 0 < near < mid < far for 1,784 of 1,864.
  The 80 exceptions are real, unexplained, and are reported rather than
  asserted away.

Level 0's first tie class has distances 12.0 / 25.0 / 40.0, a plausible
prop LOD band, and packet offsets 256, 20,592 and 26,048.

The rest is deliberately not guessed at. A field order that produces
plausible output and is wrong is the specific failure this project keeps
recording, three times now: the gameplay extent, the tfrag record
framing and the class tables were all "reasonable" and all wrong.
2026-10-11 02:06:39 +02:00

1287 lines
48 KiB
Rust

//! Integration tests against a real disc image.
//!
//! These are skipped unless `GC_DISC` points at a legally obtained disc, since
//! the repository must not contain game data. When it is set they check the
//! identification and unpack results against the committed hash table.
//!
//! ```sh
//! GC_DISC="path/to/disc.iso" cargo test -p gc-extract --test disc
//! ```
use std::path::{Path, PathBuf};
/// The disc under test, if the environment names one.
fn disc() -> Option<PathBuf> {
let p = std::env::var_os("GC_DISC")?;
let p = PathBuf::from(p);
p.is_file().then_some(p)
}
/// Skip a test with a clear reason rather than failing.
macro_rules! require_disc {
() => {
match disc() {
Some(p) => p,
None => {
eprintln!("skipped: set GC_DISC to a Going Commando disc image to run this");
return;
}
}
};
}
#[test]
fn identifies_the_supported_build() {
let path = require_disc!();
let info = gc_extract::identify::identify(&path).expect("disc should identify");
assert_eq!(info.serial, "SCUS_972.68");
assert_eq!(info.volume_id, "RATCHETANDCLANK2");
assert!(
info.is_target(),
"expected the supported build, got: {}",
info.verdict()
);
assert_eq!(
info.boot_elf_sha1,
gc_extract::identify::TARGET_BOOT_ELF_SHA1,
"boot ELF SHA-1 differs from the recorded retail value"
);
assert_eq!(info.boot_elf_size, 2_618_684);
// This disc is NTSC; the movement constants assume 60 Hz.
assert!(!info.is_pal(), "test disc should be NTSC");
}
#[test]
fn agrees_with_the_python_reference_identifier() {
let path = require_disc!();
let info = gc_extract::identify::identify(&path).expect("disc should identify");
// tools/identify-disc.py is the reference implementation and prints these
// two values. If they ever disagree, one of them has a bug.
// Run from the workspace root so the relative path to the tool resolves.
let root = std::path::Path::new(env!("CARGO_MANIFEST_DIR"))
.parent()
.and_then(|p| p.parent())
.expect("the crate should live two levels below the workspace root")
.to_path_buf();
let py = std::process::Command::new("python3")
.arg(root.join("tools/identify-disc.py"))
.arg(&path)
.current_dir(&root)
.output()
.expect("python3 should be available to run the reference identifier");
assert!(
py.status.success(),
"the reference identifier failed:\n{}",
String::from_utf8_lossy(&py.stderr)
);
let text = String::from_utf8_lossy(&py.stdout);
assert!(
text.contains(&format!("serial {}", info.serial)),
"serial disagrees with the reference identifier:\n{text}"
);
assert!(
text.contains(&format!("SHA-1 {}", info.boot_elf_sha1)),
"boot ELF SHA-1 disagrees with the reference identifier:\n{text}"
);
}
#[test]
fn unpacks_and_matches_the_committed_table() {
let path = require_disc!();
let table_path = Path::new(env!("CARGO_MANIFEST_DIR")).join("data/gc-files.tsv");
let table_text =
std::fs::read_to_string(&table_path).expect("the hash table should be committed");
let expected = gc_extract::verify::parse_table(&table_text);
assert!(
expected.len() > 5000,
"expected a full table, got {} rows",
expected.len()
);
// Unpack into a temporary directory so the test leaves nothing behind.
let tmp = std::env::temp_dir().join(format!("gc-unpack-{}", std::process::id()));
let _ = std::fs::remove_dir_all(&tmp);
std::fs::create_dir_all(&tmp).expect("should create a temp directory");
let files = gc_extract::unpack::unpack(&path, &tmp).expect("unpack should succeed");
// Every unpacked file must match the recorded size and hash.
let report = gc_extract::verify::verify(&tmp, &expected);
let _ = std::fs::remove_dir_all(&tmp);
assert!(
report.ok(),
"unpacked data does not match the committed table:\n{}",
report.summary()
);
assert_eq!(
files.len(),
expected.len(),
"unpack produced a different file count"
);
}
#[test]
fn every_container_parses() {
let path = require_disc!();
let iso = gc_formats::iso9660::IsoImage::open(&path).expect("ISO should open");
let containers: Vec<_> = iso
.files
.iter()
.filter(|e| e.name.starts_with("G/") && e.name.ends_with(".WAD"))
.collect();
// 92 `G/*.WAD` containers: 27 LEVEL, 27 AUDIO, 27 SCENE, 11 globals.
assert_eq!(containers.len(), 92, "expected 92 asset containers");
// MPEG1 and MPEG2 are raw video streams with no table; the other 90 must
// all parse as indexed containers.
let raw_video: Vec<&str> = containers
.iter()
.map(|c| c.name.as_str())
.filter(|n| *n == "G/MPEG1.WAD" || *n == "G/MPEG2.WAD")
.collect();
assert_eq!(
raw_video.len(),
2,
"expected MPEG1 and MPEG2 to be the raw streams"
);
// The per-level families must all be present, at 27 each.
for family in ["LEVEL", "AUDIO", "SCENE"] {
let n = containers
.iter()
.filter(|c| {
let stem = c.name.trim_start_matches("G/").trim_end_matches(".WAD");
stem.strip_prefix(family)
.map(|rest| !rest.is_empty() && rest.chars().all(|ch| ch.is_ascii_digit()))
.unwrap_or(false)
})
.count();
assert_eq!(n, 27, "expected 27 {family}<n>.WAD containers, found {n}");
}
for entry in &containers {
if raw_video.contains(&entry.name.as_str()) {
continue;
}
let data = gc_formats::iso9660::read_at(&path, entry.lba, entry.size)
.expect("read should succeed");
let kind = gc_formats::global_wad::RangeKind::for_container(&entry.name);
let container = gc_formats::global_wad::GlobalWad::parse_with(&data, kind)
.unwrap_or_else(|e| panic!("{} failed to parse: {e}", entry.name));
assert!(
!container.entries.is_empty(),
"{} parsed but had no entries",
entry.name
);
}
}
/// The level container header is the first typed structure we parse from real
/// data, and the tiling invariant is the check that holds on every level rather
/// than one hand-picked sample.
#[test]
fn level_headers_tile_their_containers() {
let path = require_disc!();
let iso = gc_formats::iso9660::IsoImage::open(&path).expect("ISO should open");
let mut checked = 0;
for entry in iso.files.iter().filter(|e| e.name.starts_with("G/LEVEL")) {
let data = gc_formats::iso9660::read_at(&path, entry.lba, 0x60).expect("read header");
let h = gc_formats::level_wad::LevelHeader::parse(&data)
.unwrap_or_else(|e| panic!("{}: {e}", entry.name));
assert_eq!(h.header_size, 0x60, "{}", entry.name);
assert_eq!(
h.runtime_sector, 0,
"{}: runtime sector field should be 0 on disc",
entry.name
);
// Every present extent must start where the previous one ended.
let extents = h.ordered_extents();
for w in extents.windows(2) {
let (pn, p) = w[0];
let (nn, n) = w[1];
assert_eq!(
p.offset + p.size,
n.offset,
"{}: gap or overlap between {} and {}",
entry.name,
pn.name(),
nn.name()
);
}
// Nothing may fall outside the container. The last extent may end one
// sector past the file end through sector rounding, hence `+ 1`.
let container_sectors = (entry.size / 2048) as i32;
for (name, r) in &extents {
assert!(
r.offset >= 0 && r.offset + r.size <= container_sectors + 1,
"{}: {} extent {:?} is outside the container ({container_sectors} sectors)",
entry.name,
name.name(),
r
);
}
checked += 1;
}
assert_eq!(checked, 27, "expected 27 level containers");
}
/// Level ids are not file order: `LEVEL21.WAD` reports 30. Anything that keys
/// off the container index would silently mislabel that planet.
#[test]
fn level_ids_are_not_container_indices() {
let path = require_disc!();
let iso = gc_formats::iso9660::IsoImage::open(&path).expect("ISO should open");
// The ISO filesystem lists names alphabetically, so LEVEL10 sorts before
// LEVEL2. Order by the numeric suffix, which is what the container names
// mean.
let mut levels: Vec<(usize, &gc_formats::iso9660::DirEntry)> = iso
.files
.iter()
.filter(|e| e.name.starts_with("G/LEVEL"))
.map(|e| {
let n: usize = e
.name
.trim_start_matches("G/LEVEL")
.trim_end_matches(".WAD")
.parse()
.expect("level container names end in a number");
(n, e)
})
.collect();
levels.sort_by_key(|(n, _)| *n);
let mut mismatches = Vec::new();
for (index, (_, entry)) in levels.iter().enumerate() {
let data = gc_formats::iso9660::read_at(&path, entry.lba, 0x60).expect("read header");
let h = gc_formats::level_wad::LevelHeader::parse(&data).expect("parse");
if h.id as usize != index {
mismatches.push(format!(
"{}: id {} but is container {index}",
entry.name, h.id
));
}
}
// Exactly one level is out of step: the gap left by a removed level.
assert_eq!(
mismatches.len(),
1,
"expected exactly one level whose id differs from its container index, got {mismatches:?}"
);
assert!(
mismatches[0].contains("LEVEL21"),
"unexpected mismatch: {mismatches:?}"
);
}
/// Sizes in the level header are sector counts. If they were byte counts, the
/// extents could not tile a container this size, so this also guards against
/// "fixing" the parser to read them as bytes.
#[test]
fn level_extent_sizes_are_sector_counts() {
let path = require_disc!();
let iso = gc_formats::iso9660::IsoImage::open(&path).expect("ISO should open");
let entry = iso.find("G/LEVEL0.WAD").expect("level 0");
let data = gc_formats::iso9660::read_at(&path, entry.lba, 0x60).expect("read header");
let h = gc_formats::level_wad::LevelHeader::parse(&data).expect("parse");
// Sound bank occupies sectors 1..735 and data 735..7219.
assert_eq!(h.sound_bank.offset, 1);
assert_eq!(h.sound_bank.size, 734);
assert_eq!(h.data.offset, 735);
// Read as bytes, 734 would be under four sectors and the tiling would break.
assert_eq!(h.sound_bank.byte_len(), 734 * 2048);
}
/// The level data extent is a container of byte ranges. Its header locates the
/// geometry index and the compressed geometry, and every range must lie inside
/// the extent on all 27 levels.
#[test]
fn level_data_extents_are_in_range() {
let path = require_disc!();
let iso = gc_formats::iso9660::IsoImage::open(&path).expect("ISO should open");
let mut checked = 0;
for entry in iso.files.iter().filter(|e| e.name.starts_with("G/LEVEL")) {
let raw =
gc_formats::iso9660::read_at(&path, entry.lba, entry.size).expect("read container");
let lh = gc_formats::level_wad::LevelHeader::parse(&raw).expect("level header");
let data = lh.data;
let Some(offset) = data.byte_offset() else {
continue;
};
let len = data.byte_len() as usize;
let extent = &raw[offset as usize..offset as usize + len];
let dh = gc_formats::level_data::LevelDataHeader::parse(extent)
.unwrap_or_else(|e| panic!("{}: data extent header: {e}", entry.name));
for (part, r) in dh.present_parts() {
assert!(
r.end() <= extent.len() as u64,
"{}: {part:?} ends at {} but the extent is {} bytes",
entry.name,
r.end(),
extent.len()
);
}
// The geometry is the big one and must be substantial.
assert!(
dh.core_data.size > 1_000_000,
"{}: core_data is only {} bytes",
entry.name,
dh.core_data.size
);
checked += 1;
}
assert_eq!(checked, 27, "expected 27 level containers");
}
/// The geometry must decompress. This is the first test that touches real level
/// content rather than headers.
#[test]
fn level_geometry_decompresses() {
let path = require_disc!();
let iso = gc_formats::iso9660::IsoImage::open(&path).expect("ISO should open");
let entry = iso.find("G/LEVEL0.WAD").expect("level 0");
let raw = gc_formats::iso9660::read_at(&path, entry.lba, entry.size).expect("read container");
let lh = gc_formats::level_wad::LevelHeader::parse(&raw).expect("level header");
let data = lh.data;
let extent = &raw[data.byte_offset().unwrap() as usize
..(data.byte_offset().unwrap() + data.byte_len()) as usize];
let dh = gc_formats::level_data::LevelDataHeader::parse(extent).expect("data header");
let core = dh
.core_data
.slice(extent, extent.len())
.expect("core_data slice");
assert!(
gc_formats::wad::is_wad(core),
"core_data should start with the WAD magic"
);
let decoded = gc_formats::wad::decompress(core).expect("core_data should decompress");
assert!(
decoded.len() > core.len(),
"decompressed geometry ({}) should exceed the compressed size ({})",
decoded.len(),
core.len()
);
}
/// The terrain itself. This is the first test to touch real level content: it
/// parses the tfrags directory and decodes vertex positions from every patch.
///
/// The gate is deliberately about *coverage*, not correctness of a sample: a
/// parser that works on one tfrag and silently returns `None` on the rest would
/// otherwise pass.
#[test]
fn tfrag_vertices_decode_for_every_level() {
require_disc!();
// Opening the image also confirms the disc is readable, not merely present.
gc_formats::iso9660::IsoImage::open(std::path::Path::new(
&std::env::var("GC_DISC").expect("GC_DISC is set by require_disc!"),
))
.expect("ISO should open");
// Where the unpacked data lives. GC_EXTRACTED overrides; otherwise the
// default location used during development.
let data = std::env::var_os("GC_EXTRACTED")
.map(PathBuf::from)
.unwrap_or_else(|| {
let home = std::env::var("HOME").unwrap_or_else(|_| ".".to_string());
PathBuf::from(home).join("Documents/gc-extracted")
});
if !data.exists() {
eprintln!(
"skipped: unpack the disc first, e.g.\
gc-extract unpack <disc.iso> ~/Documents/gc-extracted\
or point GC_EXTRACTED at an existing unpack"
);
return;
}
let mut levels = 0usize;
let mut total_verts = 0usize;
let mut total_tfrags = 0usize;
for n in 0..27 {
let dir = data.join(format!("level{n}"));
let core_path = dir.join("core_data.bin");
let index_path = dir.join("core_index.bin");
if !core_path.exists() || !index_path.exists() {
continue;
}
let core = std::fs::read(&core_path).expect("core_data");
let index = std::fs::read(&index_path).expect("core_index");
// The tfrags block starts at the core header's 0x08 field and runs to
// the next region that exists.
let region_start =
|off: usize| -> i32 { i32::from_le_bytes(index[off..off + 4].try_into().unwrap()) };
let start = region_start(0x08) as usize;
let end = [0x0c_usize, 0x10, 0x14]
.iter()
.map(|&o| region_start(o))
.filter(|&v| v > 0)
.min()
.unwrap_or(core.len() as i32) as usize;
let block = &core[start..end];
let header = gc_formats::tfrag::TfragsBlock::parse(block).expect("tfrags block header");
assert_eq!(header.table_offset, 0x40, "level{n}: table offset");
let table_offset = header.table_offset as usize;
let mut decoded = 0usize;
let mut verts = 0usize;
for i in 0..header.tfrag_count as usize {
let th = header.header(block, i).expect("tfrag header");
let data_base = table_offset.wrapping_add(th.data as usize);
if data_base >= block.len() {
continue;
}
let slice = &block[data_base..];
if let Some(p) = gc_formats::tfrag::tfrag_positions(slice, &th) {
decoded += 1;
verts += p.len();
assert_eq!(p.len(), th.vert_count as usize);
}
}
assert!(header.tfrag_count > 0, "level{n}: no tfrags");
assert_eq!(
decoded, header.tfrag_count as usize,
"level{n}: only {decoded} of {} tfrags decoded",
header.tfrag_count
);
levels += 1;
total_tfrags += header.tfrag_count as usize;
total_verts += verts;
}
assert!(levels > 0, "no unpacked levels were found");
assert!(
total_tfrags > 5000,
"expected thousands of tfrags, got {total_tfrags}"
);
assert!(
total_verts > 100_000,
"expected 100k+ vertices, got {total_verts}"
);
eprintln!("decoded {total_verts} vertices from {total_tfrags} tfrags across {levels} levels");
}
/// Terrain topology: strips and index arrays must expand to exactly the
/// triangle count each patch's header claims.
///
/// `tri_count` is stored in the patch header but is not derivable from the
/// lists directly, so reproducing it on all 18,102 patches is a strong check
/// that the strip walk, the index bank and the LOD assignment are all right.
/// Triangle indices must also stay inside the vertex-info range for the LOD.
#[test]
fn tfrag_topology_reproduces_the_header_triangle_count() {
require_disc!();
gc_formats::iso9660::IsoImage::open(std::path::Path::new(
&std::env::var("GC_DISC").expect("GC_DISC is set by require_disc!"),
))
.expect("ISO should open");
let data = std::env::var_os("GC_EXTRACTED")
.map(PathBuf::from)
.unwrap_or_else(|| {
let home = std::env::var("HOME").unwrap_or_else(|_| ".".to_string());
PathBuf::from(home).join("Documents/gc-extracted")
});
if !data.exists() {
eprintln!("skipped: unpack the disc first");
return;
}
let mut patches = 0usize;
let mut triangles = 0usize;
let mut levels = 0usize;
for n in 0..27 {
let dir = data.join(format!("level{n}"));
let core = match std::fs::read(dir.join("core_data.bin")) {
Ok(c) => c,
Err(_) => continue,
};
let index = match std::fs::read(dir.join("core_index.bin")) {
Ok(i) => i,
Err(_) => continue,
};
let region =
|off: usize| i32::from_le_bytes(index[off..off + 4].try_into().unwrap()) as usize;
let start = region(0x08);
let end = [0x0c_usize, 0x10, 0x14]
.iter()
.map(|&o| region(o))
.filter(|&v| v > 0)
.min()
.unwrap_or(core.len());
let block = &core[start..end];
let header = gc_formats::tfrag::TfragsBlock::parse(block).expect("tfrags block header");
let table = header.table_offset as usize;
for i in 0..header.tfrag_count as usize {
let th = header.header(block, i).expect("tfrag header");
let data_base = table.wrapping_add(th.data as usize);
if data_base >= block.len() {
continue;
}
let g = gc_formats::tfrag::parse_tfrag(&block[data_base..], &th)
.unwrap_or_else(|e| panic!("level{n} patch {i}: {e}"));
let tris = gc_formats::tfrag::tfrag_triangles(&g, 0)
.unwrap_or_else(|e| panic!("level{n} patch {i}: {e}"));
assert_eq!(
tris.len(),
th.tri_count as usize,
"level{n} patch {i}: {} triangles, header says {}",
tris.len(),
th.tri_count
);
let vinfo = g.lod_vinfo_count(0);
for t in &tris {
let idx = [t.a as usize, t.b as usize, t.c as usize];
assert!(
idx.iter().all(|&v| v < vinfo),
"level{n} patch {i}: triangle index outside {vinfo} vertex-info entries"
);
assert!((t.ad_gif as usize) < g.ad_gifs.len());
}
patches += 1;
triangles += tris.len();
}
levels += 1;
}
assert!(levels > 0, "no unpacked levels were found");
assert!(patches > 18_000, "expected 18k+ patches, got {patches}");
assert!(
triangles > 700_000,
"expected 700k+ triangles, got {triangles}"
);
eprintln!("reproduced {triangles} triangles across {patches} patches in {levels} levels");
}
/// Texture bindings: every ad-gif a patch uses must index an entry that
/// actually exists in the level's texture table, and the light array must be
/// one record per vertex.
///
/// The texture table is the join between tfrags and the texel data, so an
/// out-of-range index here means the level's geometry and its textures have
/// been misread independently of each other.
#[test]
fn tfrag_ad_gifs_index_the_level_texture_table() {
require_disc!();
gc_formats::iso9660::IsoImage::open(std::path::Path::new(
&std::env::var("GC_DISC").expect("GC_DISC is set by require_disc!"),
))
.expect("ISO should open");
let data = std::env::var_os("GC_EXTRACTED")
.map(PathBuf::from)
.unwrap_or_else(|| {
let home = std::env::var("HOME").unwrap_or_else(|_| ".".to_string());
PathBuf::from(home).join("Documents/gc-extracted")
});
if !data.exists() {
eprintln!("skipped: unpack the disc first");
return;
}
let mut patches = 0usize;
let mut ad_gifs = 0usize;
let mut textures_seen = 0usize;
let mut textures_total = 0usize;
let mut levels = 0usize;
for n in 0..27 {
let dir = data.join(format!("level{n}"));
let core = match std::fs::read(dir.join("core_data.bin")) {
Ok(c) => c,
Err(_) => continue,
};
let index = match std::fs::read(dir.join("core_index.bin")) {
Ok(i) => i,
Err(_) => continue,
};
let ch = gc_formats::level_core::LevelCoreHeader::parse(&index).expect("core header");
let textures = gc_formats::level_core::texture_table(&index, ch.tfrag_textures)
.expect("texture table");
assert!(!textures.is_empty(), "level{n}: no tfrag textures");
// Indices are per-level, so the pair is what identifies a texture.
let mut level_seen = std::collections::BTreeSet::new();
let region =
|off: usize| i32::from_le_bytes(index[off..off + 4].try_into().unwrap()) as usize;
let start = region(0x08);
let end = [0x0c_usize, 0x10, 0x14]
.iter()
.map(|&o| region(o))
.filter(|&v| v > 0)
.min()
.unwrap_or(core.len());
let block = &core[start..end];
let header = gc_formats::tfrag::TfragsBlock::parse(block).expect("tfrags block header");
let table = header.table_offset as usize;
for i in 0..header.tfrag_count as usize {
let th = header.header(block, i).expect("tfrag header");
let data_base = table.wrapping_add(th.data as usize);
if data_base >= block.len() {
continue;
}
let g = gc_formats::tfrag::parse_tfrag(&block[data_base..], &th)
.unwrap_or_else(|e| panic!("level{n} patch {i}: {e}"));
assert_eq!(
g.lights.len(),
th.vert_count as usize,
"level{n} patch {i}: {} light records for {} vertices",
g.lights.len(),
th.vert_count
);
assert_eq!(
g.rgba.len(),
th.rgba_size as usize * 4,
"level{n} patch {i}: rgba"
);
for a in &g.ad_gifs {
let t = a.texture_index();
assert!(
t < textures.len(),
"level{n} patch {i}: texture {} outside the {} entry table",
t,
textures.len()
);
let tex = &textures[t];
assert!(
tex.width > 0 && tex.height > 0 && tex.width <= 256 && tex.height <= 256,
"level{n} patch {i}: texture {t} is {}x{}",
tex.width,
tex.height
);
level_seen.insert(t);
ad_gifs += 1;
}
patches += 1;
}
textures_seen += level_seen.len();
textures_total += textures.len();
levels += 1;
}
assert!(levels > 0, "no unpacked levels were found");
assert!(patches > 18_000, "expected 18k+ patches, got {patches}");
// Most of each level's texture table should be referenced by some tfrag. A
// handful genuinely go unused; if that share grows, the ad-gif walk has
// started missing primitives rather than the data having spare entries.
let covered = textures_seen as f64 / textures_total as f64;
assert!(
covered > 0.85,
"only {textures_seen} of {textures_total} level textures referenced ({:.1}%)",
covered * 100.0
);
eprintln!(
"{ad_gifs} ad-gifs over {patches} patches reference {textures_seen}/{textures_total} level textures"
);
}
/// Level textures decode: every tfrag texture's base level must resolve to a
/// plausible RGBA image.
///
/// This is the join between the texture table, the texel block and GS RAM, so
/// it is where a wrong CLUT remap, a wrong alpha scale or a wrong pixel base
/// would show up. The check is deliberately about *shape*, not specific
/// colours: a decoded image is plausible when it is fully opaque, is not
/// uniformly one colour, and uses more than a handful of distinct entries.
#[test]
fn tfrag_textures_decode_to_plausible_images() {
require_disc!();
gc_formats::iso9660::IsoImage::open(std::path::Path::new(
&std::env::var("GC_DISC").expect("GC_DISC is set by require_disc!"),
))
.expect("ISO should open");
let data = std::env::var_os("GC_EXTRACTED")
.map(PathBuf::from)
.unwrap_or_else(|| {
let home = std::env::var("HOME").unwrap_or_else(|_| ".".to_string());
PathBuf::from(home).join("Documents/gc-extracted")
});
if !data.exists() {
eprintln!("skipped: unpack the disc first");
return;
}
let mut decoded = 0usize;
let mut opaque = 0usize;
let mut multi_colour = 0usize;
let mut flat = 0usize;
for n in 0..27 {
let dir = data.join(format!("level{n}"));
let core = match std::fs::read(dir.join("core_data.bin")) {
Ok(c) => c,
Err(_) => continue,
};
let index = match std::fs::read(dir.join("core_index.bin")) {
Ok(i) => i,
Err(_) => continue,
};
let gs = match std::fs::read(dir.join("gs_ram.bin")) {
Ok(g) => g,
Err(_) => {
eprintln!("level{n}: no gs_ram.bin, skipping");
continue;
}
};
let ch = gc_formats::level_core::LevelCoreHeader::parse(&index).expect("core header");
let textures_at = ch.textures_base.max(0) as usize;
let texture_block = &core[textures_at..];
let table =
gc_formats::level_core::texture_table(&index, ch.tfrag_textures).expect("table");
for (i, e) in table.iter().enumerate() {
let img = gc_formats::texture::base_image(texture_block, &gs, e)
.unwrap_or_else(|err| panic!("level{n} texture {i}: {err}"));
let t = img.decode().unwrap();
let texels = (e.width as i32) * (e.height as i32);
assert_eq!(t.rgba.len(), (texels * 4) as usize);
assert_eq!(t.width, e.width as u32);
decoded += 1;
// Count distinct colours and how many texels are fully opaque.
let mut seen = std::collections::HashSet::new();
let mut op = 0usize;
for px in t.rgba.chunks_exact(4) {
seen.insert([px[0], px[1], px[2], px[3]]);
if px[3] == 0xff {
op += 1;
}
}
if seen.len() > 8 {
multi_colour += 1;
} else {
flat += 1;
}
if op == texels as usize {
opaque += 1;
}
}
}
assert!(decoded > 1_500, "only {decoded} textures decoded");
// Level art is mostly opaque and has real detail. A flat, transparent or
// single-colour result almost always means a CLUT or offset mistake.
let opaque_pct = opaque as f64 / decoded as f64;
let detail_pct = multi_colour as f64 / decoded as f64;
assert!(
opaque_pct > 0.9,
"only {opaque:.1}% of textures are fully opaque"
);
assert!(
detail_pct > 0.9,
"only {detail_pct:.1} of textures have >8 colours"
);
eprintln!(
"{decoded} textures decoded: {:.1}% fully opaque, {:.1}% with >8 colours ({flat} flat)",
opaque_pct * 100.0,
detail_pct * 100.0
);
}
/// LOD linkage: every LOD-01 and LOD-0 vertex-info entry must resolve to a
/// first parent that exists and to positions inside the patch.
///
/// The parent-index arrays are V4_8 unpacks separated from the strips and the
/// strip indices only by their VU address, so a misclassification here is
/// silent: the arrays still parse, they just hold the wrong numbers. Resolving
/// every entry is what catches it.
#[test]
fn tfrag_lod_parents_resolve_for_every_entry() {
require_disc!();
gc_formats::iso9660::IsoImage::open(std::path::Path::new(
&std::env::var("GC_DISC").expect("GC_DISC is set by require_disc!"),
))
.expect("ISO should open");
let data = std::env::var_os("GC_EXTRACTED")
.map(PathBuf::from)
.unwrap_or_else(|| {
let home = std::env::var("HOME").unwrap_or_else(|_| ".".to_string());
PathBuf::from(home).join("Documents/gc-extracted")
});
if !data.exists() {
eprintln!("skipped: unpack the disc first");
return;
}
let mut patches = 0usize;
let mut entries = 0usize;
let mut lod01 = 0usize;
let mut lod0 = 0usize;
let mut resolved_common = 0usize;
let mut common_total = 0usize;
let mut primary_failed = 0usize;
let mut extras_unresolved = 0usize;
for n in 0..27 {
let dir = data.join(format!("level{n}"));
let core = match std::fs::read(dir.join("core_data.bin")) {
Ok(c) => c,
Err(_) => continue,
};
let index = match std::fs::read(dir.join("core_index.bin")) {
Ok(i) => i,
Err(_) => continue,
};
let region =
|off: usize| i32::from_le_bytes(index[off..off + 4].try_into().unwrap()) as usize;
let start = region(0x08);
let end = [0x0c_usize, 0x10, 0x14]
.iter()
.map(|&o| region(o))
.filter(|&v| v > 0)
.min()
.unwrap_or(core.len());
let block = &core[start..end];
let header = gc_formats::tfrag::TfragsBlock::parse(block).expect("tfrags block");
let table = header.table_offset as usize;
for i in 0..header.tfrag_count as usize {
let th = header.header(block, i).expect("tfrag header");
let data_base = table.wrapping_add(th.data as usize);
if data_base >= block.len() {
continue;
}
let g = gc_formats::tfrag::parse_tfrag(&block[data_base..], &th)
.unwrap_or_else(|e| panic!("level{n} patch {i}: {e}"));
common_total += g.vinfo_tier[0];
if n == 0 && patches < 5 {
eprintln!(
"p{i}: tier={:?} n01={} n0={} p01={}b x01={}b p0={}b x0={}b",
g.vinfo_tier,
g.vu_positions_lod_01_count,
g.vu_positions_lod_0_count,
g.parent_indices_lod01.len(),
g.unk_indices_2_lod01.len(),
g.parent_indices_lod0.len(),
g.unk_indices_2_lod0.len()
);
}
for v in 0..g.vertex_info.len() {
entries += 1;
match gc_formats::tfrag::tfrag_lod_link(&g, v) {
Some(link) => {
if v < g.vinfo_tier[0] {
resolved_common += 1;
}
// Parents must index real vertex info and real positions.
assert!(
link.parent1_vinfo < g.vertex_info.len(),
"level{n} patch {i}: entry {v} parent {} outside {} entries",
link.parent1_vinfo,
g.vertex_info.len()
);
assert!(link.own_position < g.positions.len());
assert!(link.parent1_position < g.positions.len());
assert!(link.parent2_position < g.positions.len());
// The first parent of a LOD-01 entry is always a common one.
if link.tier == gc_formats::tfrag::TfragMorphTier::Lod01 {
assert!(
link.parent1_vinfo < g.vinfo_tier[0],
"level{n} patch {i}: LOD-01 entry {v} parent {} is not a common entry",
link.parent1_vinfo
);
lod01 += 1;
} else {
lod0 += 1;
}
}
None => {
// Distinguish the two kinds of LOD entry. A *primary*
// entry has a real position and a recorded parent and
// must always resolve; an *extra* entry is a
// non-position bookkeeping record whose array address
// can collide with the strip index array.
let c = g.vinfo_tier[0];
let kind = if v < c {
None
} else if v < c + g.vinfo_tier[1] {
Some((g.vu_positions_lod_01_count, v - c, true))
} else {
Some((g.vu_positions_lod_0_count, v - c - g.vinfo_tier[1], false))
};
match kind {
None => {}
Some((prim, k, _)) if k < prim => primary_failed += 1,
Some(_) => extras_unresolved += 1,
}
}
}
}
patches += 1;
}
}
assert!(patches > 18_000, "expected 18k+ patches, got {patches}");
// A common entry never has a link: they are the full-detail positions and
// have no parent. Anything else means the tier boundaries are wrong.
assert!(
resolved_common == 0,
"{resolved_common} common entries claimed an LOD parent"
);
assert!(
lod01 > 0 && lod0 > 0,
"both LOD tiers should occur in the data"
);
assert_eq!(
primary_failed, 0,
"{primary_failed} primary LOD entries did not resolve"
);
assert_eq!(
extras_unresolved, 0,
"{extras_unresolved} extra LOD entries did not resolve"
);
// Common entries have no link; every other entry does.
assert_eq!(entries, common_total + lod01 + lod0);
eprintln!(
"{entries} vertex-info entries over {patches} patches: {common_total} common, \
{lod01} LOD-01 and {lod0} LOD-0, all resolved"
);
}
/// The level core index's class tables.
///
/// These are what put the environment on top of the terrain: tie instances,
/// moby actors and shrub foliage. They were ruled out earlier for want of an
/// entry size, which turned out to be knowable exactly.
///
/// The check is the chain: each table must end precisely where the next one
/// begins, moby (32 bytes/entry) into tie (32) into shrub (48) into the tfrag
/// texture table. That closes on all 27 levels and would not close if any
/// entry size were wrong, so it is the evidence rather than a coincidence.
#[test]
fn level_core_class_tables_tile_the_index() {
require_disc!();
gc_formats::iso9660::IsoImage::open(std::path::Path::new(
&std::env::var("GC_DISC").expect("GC_DISC is set by require_disc!"),
))
.expect("ISO should open");
let data = std::env::var_os("GC_EXTRACTED")
.map(PathBuf::from)
.unwrap_or_else(|| {
let home = std::env::var("HOME").unwrap_or_else(|_| ".".to_string());
PathBuf::from(home).join("Documents/gc-extracted")
});
if !data.exists() {
eprintln!("skipped: unpack the disc first");
return;
}
use gc_formats::level_core as lc;
let mut levels = 0usize;
let (mut moby, mut tie, mut shrub, mut textures) = (0usize, 0usize, 0usize, 0usize);
for n in 0..27 {
let dir = data.join(format!("level{n}"));
let Ok(index) = std::fs::read(dir.join("core_index.bin")) else {
continue;
};
let h = lc::LevelCoreHeader::parse(&index).expect("core header");
let end = |r: lc::ArrayRange, size: usize| r.offset as usize + r.count as usize * size;
assert_eq!(
end(h.moby_classes, lc::MOBY_CLASS_SIZE),
h.tie_classes.offset as usize,
"level{n}: moby -> tie"
);
assert_eq!(
end(h.tie_classes, lc::TIE_CLASS_SIZE),
h.shrub_classes.offset as usize,
"level{n}: tie -> shrub"
);
assert_eq!(
end(h.shrub_classes, lc::SHRUB_CLASS_SIZE),
h.tfrag_textures.offset as usize,
"level{n}: shrub -> textures"
);
// Every entry parses, and its asset offset lands inside the level.
if n == 0 {
eprintln!(
"hdr moby={:?} tie={:?} shrub={:?} tex={:?} base={}",
h.moby_classes, h.tie_classes, h.shrub_classes, h.tfrag_textures, h.textures_base
);
eprintln!("index[192..200] = {:?}", &index[192..200]);
}
let moby_v = lc::class_table(
&index,
h.moby_classes,
lc::MOBY_CLASS_SIZE,
lc::ClassEntry::parse,
)
.expect("moby classes");
let tie_v = lc::class_table(
&index,
h.tie_classes,
lc::TIE_CLASS_SIZE,
lc::ClassEntry::parse,
)
.expect("tie classes");
let shrub_v = lc::class_table(
&index,
h.shrub_classes,
lc::SHRUB_CLASS_SIZE,
lc::ShrubClassEntry::parse,
)
.expect("shrub classes");
let tex_v = lc::texture_table(&index, h.tfrag_textures).expect("tfrag textures");
assert_eq!(moby_v.len(), h.moby_classes.count as usize);
for (i, c) in moby_v.iter().chain(tie_v.iter()).enumerate() {
assert!(
c.offset_in_asset_wad >= 0,
"level{n} entry {i}: asset offset {}",
c.offset_in_asset_wad
);
}
// Billboard slots are optional: every shrub class on level 0 carries
// them all zero, so only their sign is meaningful here.
for s in &shrub_v {
assert!(s.base.offset_in_asset_wad >= 0);
assert!(
s.palette_offset >= -1 && s.texture_offset >= -1,
"level{n}: shrub billboard offsets below the -1 sentinel"
);
}
moby += moby_v.len();
tie += tie_v.len();
shrub += shrub_v.len();
textures += tex_v.len();
levels += 1;
}
assert_eq!(levels, 27, "expected all 27 levels, got {levels}");
assert!(
moby + tie + shrub > 1000,
"only {moby}+{tie}+{shrub} class entries"
);
eprintln!(
"level core index: {moby} moby, {tie} tie, {shrub} shrub classes, \
{textures} tfrag textures across {levels} levels"
);
}
/// The moby, tie and shrub class tables point into `core_data`, and they do so
/// without overlapping.
///
/// `assets_decompressed_size` is the size of `core_data` itself, so there is
/// no separate asset container: the class entries index the decompressed asset
/// lump directly. If that is right, every offset must land inside the lump, the
/// three tables must occupy disjoint spans, and each must be internally sorted
/// so the geometry is laid out in class order.
#[test]
fn class_geometry_offsets_tile_core_data_without_overlap() {
require_disc!();
gc_formats::iso9660::IsoImage::open(std::path::Path::new(
&std::env::var("GC_DISC").expect("GC_DISC is set by require_disc!"),
))
.expect("ISO should open");
let data = std::env::var_os("GC_EXTRACTED")
.map(PathBuf::from)
.unwrap_or_else(|| {
let home = std::env::var("HOME").unwrap_or_else(|_| ".".to_string());
PathBuf::from(home).join("Documents/gc-extracted")
});
if !data.exists() {
eprintln!("skipped: unpack the disc first");
return;
}
use gc_formats::level_core as lc;
let mut levels = 0usize;
for n in 0..27 {
let dir = data.join(format!("level{n}"));
let (Ok(index), Ok(core)) = (
std::fs::read(dir.join("core_index.bin")),
std::fs::read(dir.join("core_data.bin")),
) else {
continue;
};
let h = lc::LevelCoreHeader::parse(&index).expect("core header");
// The claim under test: the "asset lump" is core_data itself.
assert_eq!(
h.assets_decompressed_size as usize,
core.len(),
"level{n}: assets_decompressed_size is not core_data's length"
);
let span = |r: lc::ArrayRange, size: usize| -> Vec<usize> {
lc::class_table(&index, r, size, lc::ClassEntry::parse)
.unwrap_or_default()
.iter()
.map(|c| c.offset_in_asset_wad as usize)
.collect()
};
// Shrub entries are read as ShrubClassEntry so the offsets line up.
let shrub: Vec<usize> = lc::class_table(
&index,
h.shrub_classes,
lc::SHRUB_CLASS_SIZE,
lc::ShrubClassEntry::parse,
)
.unwrap_or_default()
.iter()
.map(|s| s.base.offset_in_asset_wad as usize)
.collect();
let moby = span(h.moby_classes, lc::MOBY_CLASS_SIZE);
let tie = span(h.tie_classes, lc::TIE_CLASS_SIZE);
// An offset of 0 marks a slot with no geometry rather than the start of
// the lump, so those are excluded from the span checks. Entries are not
// sorted by class number and the offsets are not monotonic, so nothing
// here assumes an order.
let moby_l: Vec<usize> = moby.iter().copied().filter(|&o| o != 0).collect();
let tie_l: Vec<usize> = tie.iter().copied().filter(|&o| o != 0).collect();
let shrub_l: Vec<usize> = shrub.iter().copied().filter(|&o| o != 0).collect();
for (name, v) in [("moby", &moby), ("tie", &tie), ("shrub", &shrub)] {
for &o in v {
assert!(
o < core.len(),
"level{n}: {name} offset {o} past core data ({})",
core.len()
);
}
}
// The three spans must not overlap each other.
for (an, a) in [("moby", &moby_l), ("tie", &tie_l), ("shrub", &shrub_l)] {
for (bn, b) in [("moby", &moby_l), ("tie", &tie_l), ("shrub", &shrub_l)] {
// A level may have no geometry of one kind at all.
if an >= bn || a.is_empty() || b.is_empty() {
continue;
}
let (lo, hi) = (a[0], *a.last().unwrap());
for &o in b {
assert!(
o >= hi || o < lo,
"level{n}: {an} [{lo},{hi}] overlaps {bn} at {o}"
);
}
}
}
levels += 1;
}
assert_eq!(levels, 27, "expected all 27 levels, got {levels}");
eprintln!("class geometry offsets verified inside core_data on {levels} levels");
}
/// Tie class headers, as far as RAC1 and RAC2 agree.
///
/// The check that carries the weight is `o_class`: the class's own number at
/// header offset 0x44 equals the number the core index filed it under, on every
/// class of every level. That is what makes the header base trustworthy rather
/// than merely plausible.
#[test]
fn tie_class_headers_match_their_index_entry() {
require_disc!();
gc_formats::iso9660::IsoImage::open(std::path::Path::new(
&std::env::var("GC_DISC").expect("GC_DISC is set by require_disc!"),
))
.expect("ISO should open");
let data = std::env::var_os("GC_EXTRACTED")
.map(PathBuf::from)
.unwrap_or_else(|| {
let home = std::env::var("HOME").unwrap_or_else(|_| ".".to_string());
PathBuf::from(home).join("Documents/gc-extracted")
});
if !data.exists() {
eprintln!("skipped: unpack the disc first");
return;
}
use gc_formats::level_core as lc;
use gc_formats::tie::{TieClassHeader, TIE_CLASS_HEADER_MATCHED};
let mut levels = 0usize;
let (mut classes, mut ordered, mut unordered) = (0usize, 0usize, 0usize);
for n in 0..27 {
let dir = data.join(format!("level{n}"));
let (Ok(index), Ok(core)) = (
std::fs::read(dir.join("core_index.bin")),
std::fs::read(dir.join("core_data.bin")),
) else {
continue;
};
let h = lc::LevelCoreHeader::parse(&index).expect("core header");
let entries = lc::class_table(
&index,
h.tie_classes,
lc::TIE_CLASS_SIZE,
lc::ClassEntry::parse,
)
.expect("tie classes");
for e in &entries {
let off = e.offset_in_asset_wad as usize;
if off == 0 {
continue; // slot with no geometry
}
let at = off + TIE_CLASS_HEADER_MATCHED;
assert!(at <= core.len(), "level{n}: tie class past core data");
let t = TieClassHeader::parse(&core[off..at])
.unwrap_or_else(|err| panic!("level{n}: tie class {} header: {err}", e.o_class));
assert_eq!(t.o_class, e.o_class, "level{n}: tie o_class mismatch");
assert!(
t.far_dist > 0.0,
"level{n}: tie far distance {}",
t.far_dist
);
if 0.0 < t.near_dist && t.near_dist < t.mid_dist && t.mid_dist < t.far_dist {
ordered += 1;
} else {
unordered += 1;
}
classes += 1;
}
levels += 1;
}
assert_eq!(levels, 27, "expected all 27 levels, got {levels}");
assert!(classes > 1_500, "only {classes} tie classes");
// Ordered distances are the expected shape; the exceptions are real and
// unexplained, so they are reported rather than asserted away.
assert!(
ordered * 20 >= classes * 19,
"only {ordered} of {classes} tie classes have ordered LOD distances"
);
eprintln!(
"tie: {classes} class headers, o_class matches the index on all; \\
{ordered} have ordered LOD distances, {unordered} do not"
);
}