Re-measured on A's dressed yard. The bar clears at every value tested —
67% at the landed 0.12, 84% at 0.40, 85% at 0.45 — and the twisted rig
holds 4/4 at all three. storm_02 downdraftOfTotal 0.12 -> 0.45 per
decision 11. Both physics gates now close on the same storm JSON.
My "mathematically unachievable" claim was wrong, and the algebra says
exactly why: ratio = (f / (sin p + cos p·f))^2 depends on the REFERENCE
PITCH far more than on the downdraft. My synthetic reference was pitched
16.7 deg, where the bar genuinely is unreachable (asymptote 109%, needs
f=0.86). The yard is pitched 4.8 deg — house fascia 2.60 m to posts
3.95 m over ~16 m — where 0.45 gives 72% on paper and 85% measured. The
equation was right and the rig was fiction: I was measuring against a
sail the game cannot build. The integrator's "measured beats modelled"
call was correct, and C's 0.45 was right on the geometry that ships.
The assert now derives its reference from the yard's real pitch and says
so, with the pitch table in a comment, so the next person to touch this
can see in ten seconds why the number moves.
Also re-pointed §7's twisted rig off the 145 m2 quad decision 2 retired
onto a real 23 m2 one ('t1,p1,p2,p3', most twisted in the 18-45 band).
The repair leg's dodgy carabiner moves to p2: measured peaks are t1 2.43
/ p2 2.35 / p3 0.82 / p1 0.60 kN, and it had been sitting on p1 — the
lightest corner — so it rode out the storm and the leg skipped. It now
blows and one repair finishes 4/4. Removed its stale skip guard, which
still tested the old gusts.downdraft key.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The gust-only downdraft could not satisfy B's 60% no-free-lunch bar and the §7
twisted-survives gate together: the downdraft peaked at the gust peak, where
the horizontal peaked too, so a flat sail never reached 60% of a pitched one's
load without a spike so violent it also broke the twisted rig. The integrator
measured the pincer (0.58 -> 48% and still breaks twisted).
Fix: the downdraft is now a fraction of the LOCAL total wind speed, not of gust
power (weather.core verticalAt = -frac * localHoriz). It presses a flat roof
steadily across the whole storm — peak total 32.6 m/s dwarfs peak gust power
12.6 — so the ratio clears 60% at a gentle fraction, with no gust-peak spike.
It rides the local speed, so a tree's wind shadow shelters from falling air too.
speedAt() stays horizontal (a wind meter doesn't read falling air).
Field renamed downdraft -> downdraftOfTotal; the validator rejects the old name
rather than silently re-meaning it. The vertical now carries NO rng draws at
all, so the determinism guarantee (tuning can't re-time gusts) is structural,
not just separate-stream.
Measured both gates myself with B's SailRig (8-direction flat-vs-pitched sweep +
§7 legs). Target for storm_02 is 0.45: 69% of-max / 60% worst-heading on the
bar, twisted rated rig survives with ~21% margin. HELD at 0.12 this commit —
the current yard's only twisted quad ('h1,t2,p1,t1', ~190 m2) starts losing a
corner near 0.15 in the exact solver, so 0.45 would red B's §7. 0.12 ~= the old
gust-only 0.3 in peak downdraft (-4.2 vs -4.5 m/s). Bump to 0.45 is a one-number
joint step once A lands decision-2 anchors (18-45 m2 quads) and B re-points §7.
storm_03_southerly: campaign ramp between gentle and wildnight — peak gust 21
m/s, sustained 13, one moderate southerly change. Auto-swept by the suite.
Selftest 170/0/0 (all three §7 legs green). Verified live: downdraft/horizontal
ratio is exactly 0.12 in-game, rain occlusion still covers the bed.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
SPRINT2 decisions 3 and 5, plus Lane A's fog nit.
Decision 3 — gusts now descend. Cloth pressure goes with dot(wind, normal); a
flat panel's normal points at the sky, so in a perfectly horizontal wind the
dot is ~0 and "lie it flat and ignore the storm" was the cheapest winning rig.
A gust front is descending air, not just faster air. Per-gust downdraft
fraction in storm JSON (storm_02 0.3, storm_01 0.18, default 0.25, validated
0..1), each gust varying 0.6-1.4x. Peak downdraft in storm_02 is 4.4 m/s, 17%
of the horizontal. Lane B: the cloth-side assert is yours.
The vertical draws from its OWN rng stream, and there's an assert pinning
that: pulling it from the main stream would shift every subsequent (t0, pow)
and silently re-time storms Lane A has already hand-verified. Their carabiner
still blows at t=45.4 and cascades at t=56.
speedAt() stays horizontal — an anemometer doesn't read falling air, and a
wind meter that spikes because a gust is descending reads as a bug.
Decision 5 — debris.pieces frozen and documented in contracts.js as the seam
Lane B reads in sail.step(), with the sphere/SI/mutated-in-place semantics
spelled out and an assert tying the live shape to the contract table.
Fog: dispose() captured scene.fog by reference and step() mutates that object
in place, so restoring it restored nothing (Lane A caught it). Now captured by
value, and fog we created ourselves is removed rather than left behind.
Selftest 130/0/0 (was 121); Lane C 28 asserts.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
debris.js: hand-rolled kinematic tumble, drag ∝ speed² so the gust that
spikes a corner is the one that launches the neighbour's bin. Ground bounce
via world.heightAt (contracts.js documents it as ours), sphere-vs-player
knockdown reported to Lane D, sphere-vs-sail-node impulse duck-typed so it
lights up when Lane B exposes nodes and stays silent until then.
skyfx.js: instanced rain that wraps around the camera rather than respawning,
storm sky + procedural cloud dome, lightning, and synthesized WebAudio layers
(wind bed, howl, rain, gust whoosh on the telegraph, rope creak off the worst
corner, flog when one blows). It modulates Lane A's lights and hands them back
on dispose() rather than owning them.
weather_demo.html: graybox bench to drive all three before M0 — mock sail,
storm scrub, 4x, throw-a-crate.
Aligned to contracts.js now that it has landed: relative three imports (there
is no importmap), contracts' rng() instead of a local copy, and storm paths
resolved off import.meta.url — server.py serves the repo root, so an absolute
/world/... would have 404'd at integration.
storm_02: fix the southerly change. contracts.js puts north at -Z and the wind
vector blows toward (cos d, sin d), so the old swing to +2.6 blew toward due
south — a northerly wearing a southerly's name. Now slews to -1.35: a SSW
buster off the open side of the yard, into the house.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Implements the contracts.js wind surface (PLAN3D §4): sample(pos,t) and
gustTelegraph(t), plus storm defs as data.
The prototype scheduled gusts by integrating (wind.gustT += dt). We can't:
sample(pos,t) is called by sail/player/debris/rain at arbitrary t, so gusts
are precomputed into a timeline from a seeded PRNG at load and read from t.
Envelope shape is a faithful port — telegraph 1.5s / ramp 0.8s / hold 1.7s /
fade 1.0s.
Maths lives in weather.core.js with zero imports (no THREE, no DOM, no
Date.now), so the determinism rule is structural and the suite runs in node
without waiting on Lane A's M0.
storm_01_gentle peaks at 11 m/s; storm_02_wildnight sustains 20 m/s and gusts
to 32 (BOM 'destructive'), with the southerly change landing just before the
worst of it — the corners that were slack all storm are the ones that cop it.
15 asserts green: telegraph lead >=1.2s, wind continuity in time and space,
storm JSON validator (incl. 14 deliberately-broken defs it must reject),
determinism, sample-order independence, tree wind shadow.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
