#[cfg(test)]
mod tests;
#[derive(Clone, Copy, Debug, PartialEq, Eq)]
#[non_exhaustive]
pub struct Preregistration {
pub id: &'static str,
pub ticket: &'static str,
pub hypothesis: &'static str,
pub falsified_by: &'static str,
pub records: &'static [&'static str],
}
pub const PREREGISTERED: &[Preregistration] = &[
Preregistration {
id: "P-8",
ticket: "R-001",
hypothesis: "A weld gated on Lk u ∩ Lk v = ∅, leaving rejected pairs \
split, yields exactly 0 non-manifold edges and 0 \
non-manifold vertices on all eight fields × all extractors, \
where the unconditional weld yields N > 0.",
falsified_by: "The gated weld still producing non-manifold output — \
which would prove the surface link condition insufficient \
for index-buffer realisation, and is the more interesting \
result.",
records: &[
"non_manifold_edges_ungated",
"non_manifold_edges_gated",
"non_manifold_vertices_ungated",
"non_manifold_vertices_gated",
"rejected_merges",
"vertex_delta",
"weld_ms_ungated",
"weld_ms_gated",
],
},
Preregistration {
id: "P-9",
ticket: "R-002",
hypothesis: "For buckets of ≥3 coincident vertices, at least one \
reference field yields ≥2 distinct outputs across P seeded \
permutations of within-bucket merge order.",
falsified_by: "All P permutations byte-identical on every field — \
meaning the k-way weld is confluent and no canonical \
order is needed.",
records: &[
"distinct_outputs",
"vertex_count_spread",
"buckets_of_three_or_more",
],
},
Preregistration {
id: "P-10",
ticket: "R-003",
hypothesis: "Vertex inflation from gated-weld-plus-split is < 1%, and \
self-intersections per 1k are unchanged from the \
unconditional weld.",
falsified_by: "Inflation > 1%, meaning a real merge/split trade-off \
needing a stated policy; or self-intersections rising, \
meaning M-93's duplication artefact returns and the \
metric must be defined on welded output only.",
records: &[
"vertex_inflation_pct",
"self_intersections_per_1k_gated",
"self_intersections_per_1k_ungated",
],
},
Preregistration {
id: "P-11",
ticket: "R-004",
hypothesis: "With one canonical world_of_sample rather than an \
offset-and-add, seam cracks fall to 0 for all cell sizes — \
not only powers of two — and M-73's hairline disappears with \
no change to the transition-cell construction.",
falsified_by: "Cracks surviving canonical reconstruction, which localises \
the defect back in Transvoxel and makes it a different \
ticket.",
records: &[
"cell_size",
"lod_pair",
"crack_count",
"max_discontinuity",
"arithmetic",
],
},
Preregistration {
id: "P-12",
ticket: "R-005",
hypothesis: "The dual's superlinear cost is the four-cells-around-a-\
crossed-edge gather at stride n²: cache-miss count per \
sample rises with n for Surface Nets and stays flat for \
Marching Cubes.",
falsified_by: "Flat miss rates, pointing at branch misprediction or \
allocation instead.",
records: &[
"samples",
"extractor",
"cache_misses_per_sample",
"ns_per_sample",
],
},
Preregistration {
id: "P-13",
ticket: "R-006",
hypothesis: "M-66's non-convergent angle is bounded below by the \
dihedral angle of the feature, so it is a property of sharp \
edges rather than of resolution and is predictable from the \
field.",
falsified_by: "The angle failing to track the dihedral prediction, which \
makes it a defect with a location rather than a property.",
records: &[
"dihedral_deg",
"samples",
"measured_angle_deg",
"predicted_angle_deg",
],
},
Preregistration {
id: "P-14",
ticket: "R-003",
hypothesis: "The residual non-manifold vertices under Surface Nets and \
Dual Contouring are the one-vertex-per-cell rule meeting a \
cell that contains more than one surface component: almost \
all of them sit in cells where Manifold Dual Contouring \
emits more than one vertex, and MDC's own count is strictly \
lower on every field where either is non-zero.",
falsified_by: "A substantial share of non-manifold vertices sitting in \
cells where MDC emits exactly one vertex — which would \
mean the defect is not the one-vertex-per-cell rule and \
is somewhere else entirely.",
records: &[
"non_manifold_vertices",
"non_manifold_edges",
"multi_vertex_cells",
"nm_vertices_in_single_vertex_cells",
"worst_link_components",
],
},
Preregistration {
id: "P-15",
ticket: "R-007",
hypothesis: "More than half of the dual mesher's cycles per sample are \
spent in emit_quads, which is three unconditional O(n³) \
sweeps over the sample grid rather than work proportional \
to the surface.",
falsified_by: "emit_quads accounting for half or less, which puts the \
cost in sample or place_vertices — work Marching Cubes \
does too, at four times the IPC — and means the dual's \
IPC is lost to something other than its extra traversal.",
records: &[
"stage",
"cycles_per_sample",
"instructions_per_sample",
"ipc",
"samples",
],
},
Preregistration {
id: "P-16",
ticket: "R-008",
hypothesis: "Every vertex whose area-weighted normal is more than 90° \
from the field gradient lies on a grid edge at least one of \
whose incident cells straddles the crease — its eight \
corners do not all have the same nearer plane — so the \
phenomenon is two faces meeting inside one cell rather than \
a winding or ordering defect.",
falsified_by: "More than 5% of past-90° vertices whose incident cells \
all lie on one side of the crease, which would make it a \
defect with a location and a fix rather than a property \
of one vertex per crossed edge.",
records: &[
"dihedral_deg",
"samples",
"past90_vertices",
"past90_in_straddling_cell",
"offending_faces_per_past90_vertex",
],
},
Preregistration {
id: "P-17",
ticket: "A-025",
hypothesis: "Manifold Dual Contouring's residual non-manifold edges are \
an interior ambiguity the face decider cannot see: the \
cells sharing an offending ambiguous face report \
Interior::Joined on at least one axis sweep at a rate far \
above the same measurement over non-offending \
ambiguous-face pairs.",
falsified_by: "Offending pairs reporting Interior::Joined at about the \
same rate as the control — which would mean the residue \
is not the interior ambiguity and the one-vertex-per-cycle \
rule fails for a reason nothing in the A-002 series has \
named.",
records: &[
"samples",
"face_rule",
"offending_pairs",
"offending_with_interior_join",
"control_with_interior_join",
],
},
Preregistration {
id: "P-18",
ticket: "R-011",
hypothesis: "Every precondition a published convex decomposition method \
requires of its input mesh is already reported by \
ColliderReadiness, so a caller holding a readiness report \
has everything it needs to decide whether a mesh can be \
handed to a decomposer.",
falsified_by: "Any precondition required by a method in the audit that \
no ColliderReadiness field reports. \
Self-intersection-freedom is the standing candidate and \
this hypothesis is expected to die on it, since \
SelfIntersectionReport is a separate type the readiness \
report does not fold in — registered as a prediction \
anyway, because an expectation that is not written down \
before the count is taken is not evidence.",
records: &[
"method",
"precondition",
"required",
"readiness_field",
"covered",
],
},
Preregistration {
id: "P-19",
ticket: "S-009",
hypothesis: "The on-demand-versus-batch crossover for the generalized \
winding number is set by the batch path's one-ray-per-grid-row \
sharing, not by its point count: on a nearly-closed mesh the \
crossover query count Q* is of order N² rather than N³, \
landing within 0.5x to 4x of N² for grids from 17³ to 65³. \
The naive expectation -- that an on-demand field wins below \
N³ queries, since that is how many the batch path answers -- \
is registered here as the thing this is expected to beat.",
falsified_by: "Q* reaching a tenth of N³ or more on a nearly-closed mesh, \
which would put the cost in the per-point boundary-edge \
correction rather than in the per-row ray, and mean the \
row sharing M-299 identified is not what sets the \
crossover. Also falsified if no crossover exists at all \
above the point where batching is trivially cheaper -- a \
single query -- which would say the on-demand field has no \
regime and S-009 should be closed rather than built.",
records: &[
"samples_per_axis",
"triangles",
"boundary_edges",
"batch_total_ns",
"on_demand_ns_per_query",
"crossover_queries",
"crossover_over_n_squared",
"crossover_over_n_cubed",
],
},
Preregistration {
id: "P-20",
ticket: "R-010",
hypothesis: "Splitting a weld on a caller-supplied key moves no topology \
metric relative to the unconditional weld beyond the splits \
the key itself names: with a constant key every metric is \
identical, and with a varying key the only change is the \
vertex count rising by the number of sub-classes the key \
creates. Across all eight reference fields and every \
extractor.",
falsified_by: "Any topology metric -- non-manifold edges, non-manifold \
vertices, boundary edges -- moving where the key is \
constant, which would mean the hook itself rather than \
the key is doing something. Or, with a varying key, a \
non-manifold vertex count that rises by more than the \
split count, which would be E*4's failure reappearing: a \
partial refusal within one coincidence class leaving its \
representative a bowtie.",
records: &[
"field",
"extractor",
"key",
"vertices_after",
"splits",
"non_manifold_edges",
"non_manifold_vertices",
"boundary_edges",
],
},
Preregistration {
id: "P-21",
ticket: "R-024",
hypothesis: "A freshly extracted mesh separates exactly the sample pairs \
the field's own sign separates. For every 6-adjacent pair of \
grid samples, the mesh crosses the segment between them an \
ODD number of times when the two samples straddle the \
surface and an EVEN number when they do not -- so the \
connected components of the air sublevel set and the \
components of the same samples under mesh-cut adjacency \
agree in count and in partition. Marching Cubes achieves \
this on all eight reference fields, because its vertex is \
the root of the interpolant along the very edge being \
probed. At least one dual method does not, because it \
places its vertex by solve.",
falsified_by: "Universal agreement -- every extractor sealing every field \
at every resolution, which would be a stronger \
correctness statement than this crate currently makes and \
is worth saying so. Separately falsified, and more \
interestingly, by Marching Cubes disagreeing: that would \
put the defect in the primal path, where the crossing is \
on the interpolant by construction, and would mean the \
failure is in triangulation rather than in vertex \
placement.",
records: &[
"field",
"extractor",
"samples_per_axis",
"field_air_components",
"mesh_air_components",
"unsealed_walls",
"spurious_walls",
"mixed_regions",
],
},
Preregistration {
id: "P-22",
ticket: "T-026",
hypothesis: "Two clauses about Grosso & Zint's mean-ratio triangle \
quality, q = 4*sqrt(3)*A / sum(l_i^2). (1) \
`marching_cubes` and `marching_cubes+decider` measure the \
IDENTICAL mean ratio on every reference field, because both \
place their vertices at the root of the interpolant along a \
grid edge and a face rule changes which crossings are \
joined rather than where they are. That is the paper's own \
explanation for its MC and TMC columns agreeing to two \
decimals on all seven of its rows. (2) This crate's \
Marching Cubes lands inside 0.65 to 0.71 on a smooth \
analytic field, the band their MC occupies, whose gen2 \
figure is resolution-independent at 64, 128 and 256 cubed.",
falsified_by: "The two Marching Cubes entries differing at all, which \
would mean the face rule moves geometry and not only \
connectivity -- and would contradict the mechanism the \
paper states for its own two columns. Or a mean ratio \
outside 0.65-0.71 on a smooth analytic field, which would \
mean the metric is not implementation-independent and the \
published baseline cannot be compared against at all. The \
second is a real possibility rather than a formality: \
their MC is somebody else's code measured on somebody \
else's fields, and every cross-source comparison this \
repo has attempted so far has needed an amendment.",
records: &[
"field",
"extractor",
"samples_per_axis",
"mean_ratio",
"irregular_vertices",
"referenced_vertices",
"triangles",
],
},
Preregistration {
id: "P-23",
ticket: "R-022a",
hypothesis: "Repairing the air sublevel set's connectivity after a \
brush dig costs work proportional to the DIRTY SET and not \
to the lattice. Concretely: at a fixed brush radius, the \
number of union operations an incremental insertion-only \
update performs is constant as the lattice grows through \
33, 65 and 129 cubed, so unions divided by newly-air \
samples stays inside a narrow band and never exceeds 6 -- \
the degree of the lattice -- while a full rebuild's union \
count grows as n cubed. Digging only ever inserts, and an \
insert joins at most two trees with no replacement-edge \
search, so a union-find is the entire structure.",
falsified_by: "The incremental union count growing with n cubed at a \
fixed brush size. That is R-022's own stated falsifier \
and it would mean edit-proportional repair is \
unavailable even in the easy direction, which closes the \
whole direction rather than only this half. Separately \
falsified by unions per dirty sample exceeding 6, which \
would mean the harness is visiting something other than \
the six incident lattice edges and is measuring its own \
traversal rather than the repair.",
records: &[
"samples_per_axis",
"dirty_samples",
"incremental_unions",
"rebuild_unions",
"unions_per_dirty",
],
},
Preregistration {
id: "P-24",
ticket: "R-023",
hypothesis: "The trilinear body-saddle value F(s) is a DECISION MARGIN \
for the interior ambiguity, not merely correlated with it: \
sign(F(s)) agrees with Interior::test() on every ambiguous \
cell whose sweep has NO pole in (0, 1), and every \
disagreement between them has a pole inside the sweep. A \
pole is the term Chernyaev's test drops and is what \
Custodio's Figure 6 counterexample is built from, so that \
is where the published algorithms part company and is the \
only place H permits a difference. Thresholding |F(s)| at \
epsilon is then a one-parameter family whose epsilon = 0 \
member is the published decider exactly.",
falsified_by: "A disagreement on an ambiguous cell whose sweep has no \
pole in (0, 1). Chernyaev's quadratic is exact there, so \
a difference would mean the body-saddle value is not the \
quantity the interior test is a sign of, and the whole \
reframing collapses rather than needing a tolerance. \
Separately falsified if the two agree on every cell \
INCLUDING the poled ones, which would mean Custodio's \
correction is unreachable on this crate's fields and the \
census cannot discriminate -- a null that says the \
fixture is wrong rather than the hypothesis.",
records: &[
"field",
"samples_per_axis",
"ambiguous_cells",
"agreements",
"disagreements",
"disagreements_with_pole",
"disagreements_without_pole",
],
},
Preregistration {
id: "P-25",
ticket: "R-022b",
hypothesis: "Repairing the air sublevel set's connectivity after a \
brush FILL costs work proportional to the SHED VOLUME -- \
the air samples that leave their component -- and not to \
the surviving component, nor to the lattice. Concretely: \
at a fixed brush radius the voxels the replacement search \
visits stays flat as the lattice grows through 33, 49 and \
65 cubed, while a rebuild's visit count grows as n cubed. \
Two mechanisms, both already measured. A union-find CAN \
absorb deletion, because a parent pointer only has to \
reach the right root and a filled sample sitting mid-tree \
is never queried -- so only the shed pieces are re-rooted \
and the surviving side is never walked. And the shed \
pieces are tiny: M-320 measured the smaller side of a \
split at ONE voxel at the median and 120 at the observed \
maximum, against 227,567 air samples. The levelled HDT \
scheme is therefore unnecessary here; lockstep search \
outward from every seed, stopping when all but one \
frontier exhausts, is enough.",
falsified_by: "Visited voxels growing as n cubed at a fixed brush size, \
which would mean the search is exploring the SURVIVING \
component rather than the shed pieces -- i.e. the \
lockstep stop condition is wrong and the structure is \
walking the thing it was built to avoid walking. \
Separately and more seriously falsified by any \
disagreement between the incrementally maintained \
components and a full rebuild over the same values: \
component count, or any connected() answer. That would \
mean the structure is fast and WRONG, which is worse \
than slow and right, and it is the failure a \
measurement of cost alone cannot see.",
records: &[
"samples_per_axis",
"fills",
"dirty_samples",
"seeds",
"visited",
"splits",
"shed_components",
"vanished_components",
"rebuild_visited",
],
},
Preregistration {
id: "P-26",
ticket: "R-022b",
hypothesis: "P-25 with its MECHANISM clause replaced and its COST \
clause unchanged; see the falsification in FINDINGS as \
cross-26. Unchanged: repairing the air sublevel set after \
a brush fill costs work proportional to the SHED VOLUME, \
not to the surviving component nor to the lattice, so \
visited voxels stay flat through 33, 49 and 65 cubed at a \
fixed brush radius. Replaced: the structure is not a \
union-find but a FLAT label array -- every sample carries \
its component id directly, so re-rooting a shed piece is \
one write per member and no surviving sample can route \
through it. Flat labels fix the REPRESENTATION, not the \
SEARCH: the lockstep replacement search was always \
required and the union-find merely promised falsely that \
it could be skipped. Added: lockstep bounds work by the \
SECOND-LARGEST piece, so M-320's one-voxel median is a \
property of the edit distribution rather than of the \
structure. Bisecting a tunnel between two equal caverns \
makes both frontiers huge and visited then grows with n at \
a fixed brush size. So the prediction is stated per \
fixture: FLAT on the measured distribution, GROWING on a \
deliberate bisect.",
falsified_by: "Visited voxels growing as n cubed ON THE MEASURED \
DISTRIBUTION at a fixed brush size. Growth on the bisect \
fixture is predicted and is not falsifying; a structure \
that came out flat on BOTH would instead mean the bisect \
fixture is not adversarial and needs rebuilding, which \
is a fixture failure rather than a result. Separately \
and more seriously falsified, as in P-25, by any \
disagreement between the maintained components and a \
full rebuild over the same values -- component count, or \
any connected() answer. Fast and wrong is worse than \
slow and right.",
records: &[
"samples_per_axis",
"fixture",
"fills",
"dirty_samples",
"seeds",
"visited",
"splits",
"shed_components",
"vanished_components",
"rebuild_visited",
],
},
];
const fn str_eq(a: &str, b: &str) -> bool {
let (a, b) = (a.as_bytes(), b.as_bytes());
if a.len() != b.len() {
return false;
}
let mut i = 0;
while i < a.len() {
if a[i] != b[i] {
return false;
}
i += 1;
}
true
}
#[must_use]
pub const fn is_preregistered(id: &str) -> bool {
let mut i = 0;
while i < PREREGISTERED.len() {
if str_eq(PREREGISTERED[i].id, id) {
return true;
}
i += 1;
}
false
}
#[must_use]
pub const fn preregistration(id: &str) -> &'static Preregistration {
let mut i = 0;
while i < PREREGISTERED.len() {
if str_eq(PREREGISTERED[i].id, id) {
return &PREREGISTERED[i];
}
i += 1;
}
panic!("no such pre-registration; add it to experiment::PREREGISTERED first")
}
#[macro_export]
macro_rules! experiment {
($id:literal) => {{
const _CHECK: () = assert!(
$crate::experiment::is_preregistered($id),
"this experiment id is not pre-registered — add it to \
experiment::PREREGISTERED, in its own commit, before running \
anything"
);
$crate::experiment::preregistration($id)
}};
}