Deliberately a target rather than a description of where the library sits. Of
the scenes measured since the region block went in, only Droste Feedback at
0.324 is comfortably over; Plasma Bloom is 0.082, Voronoi Shatter and Apollonian
Gasket 0.062, Moiré Grid 0.047. Most of the library fails this, which is the
point — a bar set where the work already is measures nothing.
Third value in two days, and both previous moves were instrument corrections
rather than changes of mind: the motion block was reading zero for the entire
library, and adding the region block made the total a mean over six blocks
instead of five. Both raised every score, so 0.04 had quietly drifted down
relative to the thing it was judging. Documented as something to re-read off a
fresh gallery whenever the descriptor changes, rather than a number to carry
forward.
The marker now sits at the middle of each meter and the grades land where they
should: 0.047, 0.062 and 0.082 all red, 0.140 amber, 0.324 green.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Four stages, an identity layer, and an A/B that says the idea is right and the
reason it works is not the reason I expected.
A stage has no image of its own. It owns arrangement — a procession, a
constellation, a soloist, a swarm — and what it arranges comes from the track:
`castMain` and `castChorus` for the forms, `inkMask` and `inkValue` for the hand
they are drawn in. The identity generates a protagonist and a chorus with sides,
notches and hollows, plus an ink treatment of weight, edge, fill, outline and
posterisation. All of it travels as uniforms, so it is data rather than code and
a stage consumes it without knowing any other stage exists.
The protagonist IS the signature form rather than a second opinion about it.
They were separate draws in the first version, which let a track built on
hexagons put a round protagonist on screen — the signature said one thing and
the picture said another, and the shape trait stopped meaning anything for
stages. The cast now reads its geometry from the personality live and adds the
notches and hollows that turn a shape into a character.
Measured across seven songs, three arms, same instrument:
arm floor observed spread
stages, four of them 0.0801 0.1133 +0.0332
legacy scenes, four of them 0.0830 0.1122 +0.0292
the unrestricted generator 0.1058 0.1146 +0.0088
The prediction in EPIC-3 §7 was that sharing a cast would drop the floor
sharply. The floor did drop sharply — by a quarter — but nearly all of that came
from casting FEWER scenes per video, not from sharing content: the legacy arm,
four ordinary scenes with no cast at all, gets most of the same benefit. Stages
add about 14% on top of that.
That is worth knowing before building the other four registers. The single
largest available win was hiding in the roster size all along, and it costs one
number to take.
One result runs the wrong way and is recorded rather than explained: coupling is
+0.29 on the legacy arm and -0.18 on the stages. At twenty-one pairs neither is
distinguishable from zero, so it is a flag for a larger sample rather than a
finding.
Also fixed: a backtick inside the shader preamble's template literal, which
closed it and made every check page hang on "starting…" with no error in the
console.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Halftone Misprint is a printing fault rather than an electronic one — the image
is never damaged, only separated and reassembled out of register, and nothing
else in the library is made of dots. Droste Feedback scales the previous frame
where Time Smear translates it, so the image never clears. Analog Wow is the
continuous, wet counterpart to Scan Tear and Block Mosh: the error varies
smoothly down the frame because every line was written at a different moment.
Three things that had to be got right. The halftone ruling is a count of dots
across the frame, not a pixel pitch, or a 4K export is the same dot on a bigger
sheet. The Droste loop has to CONTRACT — expanding pushes every copy off the
edge and leaves a plume instead of a corridor. And all three expressed style
only through grain at first, which is the Side Quest 1 complaint: they now put
the track's line weight and edge softness into the dot, the ring and the band
boundary, taking the measured style response from 24/11/18 to 86/255/88.
Neither feedback scene declares a slow axis, with the numbers recorded in the
files: their own history moves the ten-second average further than any parameter
does.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Voronoi Shatter (cells with no fixed shape, re-cut on the phrase), Apollonian
Gasket (a packing built by inversion, so zooming finds more circles rather than
finer noise) and Isometric Blocks (a lit, gridded, solid surface where Floating
Geometry is bodies adrift).
Two flash failures, both the same mistake in different clothes. Apollonian's hard
depth cutoff popped a whole generation of discs in and out as the fold crossed
it — now faded rather than cut. Isometric Blocks drove block height off the low
end, so every tower in the frame grew and shrank together: 4/s. Moving the
reaction to the edges and to a hash-chosen quarter of the tops keeps the pulse
and drops the frame-wide swing.
Voronoi Shatter declares no slow axis: its re-cut puts the ten-second average
0.127 from itself between any two windows, the highest noise floor in the
library, and no parameter competes with that.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Suspension Span is two curves and a rhythm of hangers where Girder Lattice is a
texture of members. Stairwell Descent puts the vanishing point dead centre and
turns each flight, so the spiral is in the structure rather than in the motion.
Aqueduct March is masonry — the light comes through holes cut in a solid wall —
and Data Aisle is the interior, close counterpart to Neon City's exterior.
Two bugs worth naming: the arch openings compared a cell-local centre against a
global coordinate, which put every arch out in the wings and left a blank wall;
and the stairwell's depth fade was keyed on floor index, so it only darkened the
few pixels at the centre and measured as doing nothing.
Aqueduct March declares no slow axis and records the three candidates measured.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Pendulum Trace (a harmonograph over its own fading ghost), Contour Map (a survey
of a landscape with a tide in it), Shoji Grid (backlit panels that slide) and
Balance Stack (a leaning pile under a crossing sun).
Two of the four leave the slow axis undeclared and say why in the file: in a
frame this empty the camera's own drift moves the ten-second average more than
anything in the scene can, so a declaration would be a claim Phase 11 contradicts.
Phase 4's transition control changed from max(before, after) to their sum. These
scenes are calm, so casting them into the mid-shot control windows halved the
denominator while the boundary peak stayed put — 0.124 with them, 0.130 without.
For most of the window both stacks are live, four layers with accents in overlay
and screen, and a nonlinear blend of two moving stacks moves more than either
alone; "no worse than the busier half" was never a property a dissolve had. A
real pop still clears the threshold by an order of magnitude.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Turing Bloom runs activator-inhibitor in the feedback buffer, so the pattern is
formed rather than drawn — the one organic here that will not go uniform. It
declares no slow axis on purpose, and says why: its own convergence path moves
the ten-second average by 0.10, and every candidate axis measured under that.
Mycelium Web puts an organic on the ground instead of standing in front of the
camera; the colony front is legible as area, which is also what makes its axis
measurable. Scale Mosaic is a log-polar lattice with a shear, so the rows are
spirals and every scale is the track's signature form.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Rain Column, Magnet Lines and Kármán Street. The flow family was seven ways of
advecting a noise field; none of them had an upstream, an obstacle or a rule.
These do: rain falls in three parallax layers under one shear, the field lines
are exact contours of the poles' stream function so they close on themselves,
and the vortex street is shed by a body that never moves.
The slow axes took four rounds to land. A fine-grained axis — line count, drop
density — loses to the camera's own drift in the time-averaged comparison Phase
11 makes, so all three ended up on a param that moves a large low-frequency
area: streak length, pole spread, and a wake haze that dissolves the streamlines
it widens over.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Seven per family now, 42 scenes. Each one exists because of the second
line of its header comment — what makes it different from the scenes it
sits beside — since "no two scenes render the same image" is a gate with a
numeric floor:
Smoke Column (flow) a plume with a source, a body and a
dissipating head. Everything moves one way and
widens; an isotropic field has no up.
Cell Divide (organic) a partition, not objects. Every pixel belongs
to a cell, boundaries are hard, no background.
Eclipse Field (minimal) the occluder nearly fills the frame and is not
the subject — the corona around it is. The
library's one high-contrast minimal scene.
Girder Lattice (structural) the only scene whose subject is ABOVE the
camera; perspective converges downward.
Quasicrystal (geometric) five plane waves at incommensurate angles, so
the pattern has local symmetry and no tile,
no cell and no centre.
Time Smear (glitch) nothing is displaced. Each band shows the same
image at a different age — a slit-scan built
from one feedback buffer by giving each band
its own persistence.
The scaffolder produced six skeletons that passed lint and every gate
before a line of shader was written, and all six passed their per-scene
gate first time once written. That is what it was for.
Two real faults, both found by gates rather than by eye:
Cell Divide coloured each pixel by its nearest seed, and exactly on a tie
which seed is nearest comes down to the last bit of a distance. Two renders
disagreed by a whole palette step: 6/255 against a ceiling of 1, and it
also broke Phase 6's preview/export parity because that look casts it.
Blending the nearest tint with the runner-up across the membrane makes the
two answers agree in the limit — and reads better, as membranes rather than
cuts.
The lint's own "prev() with no base image" rule fired on a scene whose
comment explained why it does NOT rely on prev(). Rules that ask "does the
code do X" now run against a comment-stripped copy; the fixed-cost opt-out
still reads the original, since it is a comment.
Phase 6's parity tolerance goes from 1/255 to 2. Measured in order:
unprimed, the first pass differed on frames 0/2/3 — fixed earlier by
priming. Primed and isolated: 0/40 at delta 0, three times over. Primed,
range-warmed and run at the end of the full suite: three frames at delta 2.
The warm-up stays because it is correct, but the residue is GPU load, not
logic, and it is the same 1-2/255 Phases 5 and 7 already account for. A
real divergence scores in the tens.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Watching several finished tracks side by side turned up the problem neither
Phase 8 (too few cuts) nor Phase 9 (no through-line) addressed: the same
scene cast in two different videos looked like the same footage twice.
Section bias is nearly identical between two tracks' drops, so both sampled
their parameters around the same centre, and the library's own averageness
did the rest.
Three answers, none of them a new scene:
Temperament — a per-track hand on every parameter dial: intensity, pace,
detail, and an extremity that decides how far toward the ends of a range
the track is willing to sample. Bias comes from the section and is shared
between tracks; temperament comes from the track and is not.
Overlays — sometimes a second full scene composited over the shot, from a
different family, in a blend that preserves what is underneath and never
above 0.6 opacity. Not always: a stack that always doubled up would read
as permanently cluttered rather than as occasionally layered.
A wider palette — hue now derives from SPECTRAL TILT, the log ratio of
treble to body. The centroid is a number most masters sit in the middle
of, and the plain body/(body+treble) fraction is worse: low frequencies
carry most of the energy in all music, so it read 0.98-1.00 for
everything and four different battery tracks came out within 0.02 of
each other. The ratio is multiplicative, so its logarithm is what
spreads — the same four measure -9.3, -5.0, -4.1, -3.8. Also both ways
round the wheel (violet, magenta and pink were unreachable by
construction), four new schemes, and seeded chroma profile and lightness
curve. Closest battery pair went from 0.005 to 0.113.
Twelve scenes take the library to 36, six per family: Aurora Veil, Vortex
Drift, Tide Rings, Ink Bleed, Dust Chamber, Salt Flat, Cargo Belt, Gate
Corridor, Circuit Bloom, Truchet Fold, Signal Decay, Storm Rift. Weighted
toward the 'space' and 'shape' traits, which were thinnest and so the
signatures most likely to run a track out of cast — the Phase 9 casting
rule means the pool a track draws from is smaller than the library.
Also fixes a real one in shots.js: heavy LRU weighting was not enough to
make a section reach its whole roster, and a five-shot section still came
out 0,2,0,2,0 about a fifth of the time. An unseen companion now wins
outright; which one is still free, so only the coverage is guaranteed.
Block Mosh declared the camera trait, assigned sigCamera(p) to a p it then
never read, and passed the lint's evidence grep. The Phase 9 render gate
measured its response to the camera at exactly zero.
--- tooling ---
Adding a scene was mostly boilerplate and round-trips, which is expensive
in both senses. The irreducible cost is the shader body; everything around
it is now mechanical:
npm run new:scene -- "Name" --family=... --traits=...
writes the module, registers it, and leaves a skeleton that already passes
every gate, with name-derived constants so two skeletons are not twins.
The lint grew the rules that previously needed a GPU to catch: the dead
camera above, prev() with no base image, and large loops with no early
break (with a `// lint: fixed-cost` opt-out for a genuinely fixed-cost
sampling loop). checks.html?scene=Name runs the per-scene acceptance
battery for one scene — ten lines and a verdict instead of rendering the
whole library to find out whether one shader is alive. The same procedure
is a repo skill under .claude/skills/build-visualizer/.
--- checks changed, with the measurements ---
P5 determinism compared two WebGL CONTEXTS, which is not what it is for.
Measured: one context is bit-exact over 40 frames with feedback at 0.6;
two contexts disagree by up to 2/255 whether feedback is on or off. It now
asserts generation is byte-identical (hard) and rendering within 2/255,
since feedback compounds single-level variance.
P10's cross-track comparison measures distance RELATIVE to how much image
there is. Most scenes are mostly dark, so two genuinely different renders
— 25 bars against 53 — scored under 0.02 absolute purely because the black
background agrees with itself.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Three new scene shaders to widen the library, now that the main families are
settled. Each is a shader plus a params block, registered in the single
source of truth (scenes/registry.js), so casting, UI, arc and checks pick
them up automatically.
- Block Mosh (glitch): a datamosh. Blocks pull the feedback buffer along
per-block strokes on a bar-quantized grid so the corruption steps like an
edit rather than crawling, and spills on onsets. Fills the most iconic
gap in the glitch family.
- Neon City (structural): a receding skyline with instanced lit windows,
distinct from the rolling ridgelines and the road grid it sits alongside.
- Flora (organic): an abstract plant of swaying stalks, teardrop petals and
a bloom corona, all stamped in the track's signature shape.
Also adds HOWTO-visualizers.md, a quick reference for building the next one.
Ten new scenes, with 'minimal' first: the family was empty, so intros and
breakdowns fell through to flow/organic and every track opened at full
density. Quiet sections now land on a restful family 48/48 times across 24
seeds, 28 of them minimal.
New: Horizon Lines, Spectrum Sculpture, Slow Orb (minimal); Curl Flow
(flow); Plasma Bloom, Metaballs (organic); Kaleido Tunnel, Moiré Grid
(geometric); Ridge Terrain (structural); Scan Tear (glitch).
Four real bugs, three of which the existing gates could not have caught:
1. SHADER PROGRAMS LINK ASYNCHRONOUSLY. three.js uses
KHR_parallel_shader_compile, so draws against an unlinked program render
wrong. The heaviest scene had its first TEN frames differ from every
later render of the same frames. Preview hides this entirely; export
renders each frame once, so those frames would ship broken. Added
Engine.prime() — WebGLRenderer.compile() plus a discarded warm frame —
and the exporter now primes before encoding. Rendering a throwaway frame
and reading it back is NOT sufficient; measured, it left 3-5 frames wrong.
2. Moiré Grid declared a param on u_width, which the shader contract already
uses for stereo width. GLSL redefinition, and the only symptom was a
black frame. Lint now rejects any param uniform colliding with the
contract.
3. Spectrum Sculpture strobed at 4 flashes/s. Two causes: rotation measured
in turns meant bar-crossing frequency was bars x rate (82 bars put a
slow-looking 0.12 turns/s at 10 Hz), and hard band-tier boundaries made
every bar switch band simultaneously. Rotation is now in segment units so
the rate IS the crossing frequency, bands interpolate, and the range is
capped where the flash meter measures zero.
4. Particle Field was being chosen as a primary background despite being
mostly empty by design. Scenes now declare role: 'accent'; those are
never primary and are judged on variance rather than luminance.
Three checks were themselves wrong and were rebuilt: mean-distance metrics
unfairly fail sparse scenes for being tasteful rather than static, so
"animates" and "no duplicates" now use max channel delta.
PLAN.md §1 gains two refinements: programs must be primed before the first
frame, and even same-machine the heaviest shaders vary by one LSB under
differing GPU load — so the per-scene criterion is max delta <= 1 rather
than an identical hash. A real bug scores in the tens there.
Full suite 67/67 across all seven phases. Worst 4K frame 3.8ms,
worst flash rate 0/s, worst determinism delta 1/255. Adds README.md.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Multi-layer stacks with blend modes, feedback, post chain, and a 3D
particle layer proving the compositor is genuinely hybrid. Looks now
generate accent layers from a different family, composited additively at
low opacity, weighted by section energy so intros stay sparse.
Adds flash-rate safety (engine/flash.js), which was not in the original
plan and should have been. This generates beat-reactive video for
publication, and rapid light-dark cycling is the photosensitive-epilepsy
trigger; WCAG 2.3.1 caps it at three flashes per second. Classic Wave
measured 7-8/s at every output resolution from 96x54 to 1920x1080, so it
was a real hazard rather than a sampling artefact.
Root cause was general, not one bad shader: `u_time * u_speed` where speed
is reactively modulated. Phase is elapsed*rate, so changing the rate at
time T jumps phase by T*delta — sixty seconds in, a 0.05 wobble throws the
phase three whole units between consecutive frames, and it worsens as the
track runs. Fixed by introducing rate params:
- schema flag `rate: true` documents and marks them
- Layer.resolveParams skips reactivity on them
- ArcDriver skips drift on them
- validateModule rejects a reactive entry on one
- lint-scenes greps shaders for `u_time * u_X` and fails if X is unmarked,
so no future scene can reintroduce it
Every rate param across the six scenes is now marked. Two checks were
needed to find this: a per-look flash check, and a per-SCENE sweep at
aggressive params, since the look generator only samples part of the space
and a scene can hide an unsafe region for a long time.
Gate 10/10. Worst flash rate now 1/s. Feedback stable over 10,000 frames
(luminance 0.17-0.59, no saturation or decay). 0.17ms/frame at 1280x720.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
All five party-stage shaders now ported. Each declares its params
declaratively; uniform binding, UI controls, seeded sampling and arc
automation all derive from that one block, so a new scene costs a shader
and a schema and nothing else.
Port changes: LED-grid masks stripped, hardcoded colours replaced with
palette lookups, magic numbers lifted into params. Psychedelic Drift's
internal 15-second scene timer removed — keeping the visuals moving is the
arc driver's job, and it knows where the song's real transitions are.
ParamPanel generates controls from the schema alone and knows about no
specific scene; a hand-written control would be a bug.
Gate 8/8: schemas valid, uniforms accounted for in both directions, all
scenes compile and render, 128 range-sweep frames with no black, blown or
flat results, every param exposed in the UI, edits clamped, presets
round-trip and survive schema drift.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Engine core: Timeline (fixed dt, audio-mastered in realtime), seeded Rng,
Renderer, Layer/ShaderLayer/SceneLayer, Compositor with blend modes,
feedback and post chain.
Shader scenes are compiled against a fixed uniform contract and define only
`vec4 scene(vec2 uv, vec2 p)`, so adding a scene costs a shader plus a
params block. Deep Nebula ported from party-stage as the first one.
Gate passes, 7/7 in checks.html:
- 300 frames rendered twice are bit-identical
- a fresh Engine reproduces the same frames
- simulated dropped frames change nothing (proves dt is fixed)
- seek matches sequential playback
- 320x180 vs 1280x720 agree within 0.010 (limit 0.06)
- seeded rng reproducible, forked streams independent
- compositor reset clears feedback history
Static gates: no wall-clock or unseeded randomness in deterministic
directories; scene schemas and shader sources agree in both directions.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
