Port steps 0-1: scaffold, the oracle, and the pure bottom
Scaffolds frontend/ (shadow-cljs, reagent 1.2.0, re-frame 1.4.3) and ports
everything below the data model, with the JS kept as a numeric oracle.
domain/landmarks index tables, verbatim
domain/ring subsample, offset, simplicity
domain/geom similarity fit, procrustes, moving average
domain/raster indexed scanline fill, stencil, disc, rect
domain/palette the ramp, and the no-sampled-RGB rule
58 tests, 166 assertions. Parity with js/ on the identical 72-frame synthetic
track: fit-similarity, procrustes-mean, fit-residual, moving-average,
smooth-transforms, offset-ring and subsample-slots to 1e-9; the raster
pixel-for-pixel over the whole buffer.
Three deviations from the JS, each for a reason:
- synth.cljs jitters from a SEEDED generator, not Math.random. Parity is only
checkable if both sides can be handed the same track, and a failing assertion
has to be reproducible. `:rand-fn` takes the generator over, so oracle.mjs
stubs js/Math.random and js/ itself stays untouched.
- raster/->rgba replaces toImageData. ImageData is a DOM type and domain/ may
not touch the DOM; returning plain bytes also lets the
no-intermediate-colours assertion run in node. ui/canvas wraps it later.
- offset-ring lives in domain/ring, not domain/geom, per architecture.md: it is
an operation on an ordered traversal, not on a transform.
Step 1's "done" also names the swapped-iris vote, but pairIrises is in
pipeline.js and belongs to step 7. The precondition is asserted instead --
`:swap-iris` really does move both blocks -- so the vote will have a track that
disagrees with it when it arrives.
One finding, recorded in full in the test that measures it: smooth-transforms
buys nothing on the synthetic track. Against jitter-free ground truth, radius 1
helps by 17% on one noise realisation and hurts by 0.5% on another, so its
benefit is within noise; from radius 2 up the cost is unambiguous, and by radius
5 the filter is below the true motion's own high-frequency energy, i.e.
smoothing away performance. The test pins the shape of the knob rather than a
preferred value. This may say more about the synth's jitter being unrealistically
small (+/-0.001 normalised) than about the knob; step 6 settles it on real
footage.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-27 14:43:34 -04:00
# frontend
The ClojureScript half. See `docs/port-plan.md` for what is being built and in
what order; this file is only how to run it.
## Once
```sh
mise install # from the REPO ROOT: java 21+, node 20, clojure, python
cd frontend & & npm install
```
`java` must be 21+. On an older JDK shadow-cljs fails with "CompilerOptions has
been compiled by a more recent version of the Java Runtime", which reads like a
shadow-cljs bug and is not one. `mise install` is what prevents it.
## The tests
```sh
2026-09-27 19:01:39 -04:00
cd frontend & & mise exec -- npm test
Port steps 0-1: scaffold, the oracle, and the pure bottom
Scaffolds frontend/ (shadow-cljs, reagent 1.2.0, re-frame 1.4.3) and ports
everything below the data model, with the JS kept as a numeric oracle.
domain/landmarks index tables, verbatim
domain/ring subsample, offset, simplicity
domain/geom similarity fit, procrustes, moving average
domain/raster indexed scanline fill, stencil, disc, rect
domain/palette the ramp, and the no-sampled-RGB rule
58 tests, 166 assertions. Parity with js/ on the identical 72-frame synthetic
track: fit-similarity, procrustes-mean, fit-residual, moving-average,
smooth-transforms, offset-ring and subsample-slots to 1e-9; the raster
pixel-for-pixel over the whole buffer.
Three deviations from the JS, each for a reason:
- synth.cljs jitters from a SEEDED generator, not Math.random. Parity is only
checkable if both sides can be handed the same track, and a failing assertion
has to be reproducible. `:rand-fn` takes the generator over, so oracle.mjs
stubs js/Math.random and js/ itself stays untouched.
- raster/->rgba replaces toImageData. ImageData is a DOM type and domain/ may
not touch the DOM; returning plain bytes also lets the
no-intermediate-colours assertion run in node. ui/canvas wraps it later.
- offset-ring lives in domain/ring, not domain/geom, per architecture.md: it is
an operation on an ordered traversal, not on a transform.
Step 1's "done" also names the swapped-iris vote, but pairIrises is in
pipeline.js and belongs to step 7. The precondition is asserted instead --
`:swap-iris` really does move both blocks -- so the vote will have a track that
disagrees with it when it arrives.
One finding, recorded in full in the test that measures it: smooth-transforms
buys nothing on the synthetic track. Against jitter-free ground truth, radius 1
helps by 17% on one noise realisation and hurts by 0.5% on another, so its
benefit is within noise; from radius 2 up the cost is unambiguous, and by radius
5 the filter is below the true motion's own high-frequency energy, i.e.
smoothing away performance. The test pins the shape of the knob rather than a
preferred value. This may say more about the synth's jitter being unrealistically
small (+/-0.001 normalised) than about the knob; step 6 settles it on real
footage.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-27 14:43:34 -04:00
```
2026-09-27 19:01:39 -04:00
Two things: compile the `:test` build, run it under node.
Port steps 0-1: scaffold, the oracle, and the pure bottom
Scaffolds frontend/ (shadow-cljs, reagent 1.2.0, re-frame 1.4.3) and ports
everything below the data model, with the JS kept as a numeric oracle.
domain/landmarks index tables, verbatim
domain/ring subsample, offset, simplicity
domain/geom similarity fit, procrustes, moving average
domain/raster indexed scanline fill, stencil, disc, rect
domain/palette the ramp, and the no-sampled-RGB rule
58 tests, 166 assertions. Parity with js/ on the identical 72-frame synthetic
track: fit-similarity, procrustes-mean, fit-residual, moving-average,
smooth-transforms, offset-ring and subsample-slots to 1e-9; the raster
pixel-for-pixel over the whole buffer.
Three deviations from the JS, each for a reason:
- synth.cljs jitters from a SEEDED generator, not Math.random. Parity is only
checkable if both sides can be handed the same track, and a failing assertion
has to be reproducible. `:rand-fn` takes the generator over, so oracle.mjs
stubs js/Math.random and js/ itself stays untouched.
- raster/->rgba replaces toImageData. ImageData is a DOM type and domain/ may
not touch the DOM; returning plain bytes also lets the
no-intermediate-colours assertion run in node. ui/canvas wraps it later.
- offset-ring lives in domain/ring, not domain/geom, per architecture.md: it is
an operation on an ordered traversal, not on a transform.
Step 1's "done" also names the swapped-iris vote, but pairIrises is in
pipeline.js and belongs to step 7. The precondition is asserted instead --
`:swap-iris` really does move both blocks -- so the vote will have a track that
disagrees with it when it arrives.
One finding, recorded in full in the test that measures it: smooth-transforms
buys nothing on the synthetic track. Against jitter-free ground truth, radius 1
helps by 17% on one noise realisation and hurts by 0.5% on another, so its
benefit is within noise; from radius 2 up the cost is unambiguous, and by radius
5 the filter is below the true motion's own high-frequency energy, i.e.
smoothing away performance. The test pins the shape of the knob rather than a
preferred value. This may say more about the synth's jitter being unrealistically
small (+/-0.001 normalised) than about the knob; step 6 settles it on real
footage.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-27 14:43:34 -04:00
```
shadow-cljs compile test
node out/node-tests.js
```
2026-09-27 19:01:39 -04:00
Run them separately if a compile error is in the way.
Port steps 0-1: scaffold, the oracle, and the pure bottom
Scaffolds frontend/ (shadow-cljs, reagent 1.2.0, re-frame 1.4.3) and ports
everything below the data model, with the JS kept as a numeric oracle.
domain/landmarks index tables, verbatim
domain/ring subsample, offset, simplicity
domain/geom similarity fit, procrustes, moving average
domain/raster indexed scanline fill, stencil, disc, rect
domain/palette the ramp, and the no-sampled-RGB rule
58 tests, 166 assertions. Parity with js/ on the identical 72-frame synthetic
track: fit-similarity, procrustes-mean, fit-residual, moving-average,
smooth-transforms, offset-ring and subsample-slots to 1e-9; the raster
pixel-for-pixel over the whole buffer.
Three deviations from the JS, each for a reason:
- synth.cljs jitters from a SEEDED generator, not Math.random. Parity is only
checkable if both sides can be handed the same track, and a failing assertion
has to be reproducible. `:rand-fn` takes the generator over, so oracle.mjs
stubs js/Math.random and js/ itself stays untouched.
- raster/->rgba replaces toImageData. ImageData is a DOM type and domain/ may
not touch the DOM; returning plain bytes also lets the
no-intermediate-colours assertion run in node. ui/canvas wraps it later.
- offset-ring lives in domain/ring, not domain/geom, per architecture.md: it is
an operation on an ordered traversal, not on a transform.
Step 1's "done" also names the swapped-iris vote, but pairIrises is in
pipeline.js and belongs to step 7. The precondition is asserted instead --
`:swap-iris` really does move both blocks -- so the vote will have a track that
disagrees with it when it arrives.
One finding, recorded in full in the test that measures it: smooth-transforms
buys nothing on the synthetic track. Against jitter-free ground truth, radius 1
helps by 17% on one noise realisation and hurts by 0.5% on another, so its
benefit is within noise; from radius 2 up the cost is unambiguous, and by radius
5 the filter is below the true motion's own high-frequency energy, i.e.
smoothing away performance. The test pins the shape of the knob rather than a
preferred value. This may say more about the synth's jitter being unrealistically
small (+/-0.001 normalised) than about the knob; step 6 settles it on real
footage.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-27 14:43:34 -04:00
2026-09-27 19:01:39 -04:00
**Run them through `mise` **, or make sure `mise` 's node is first on PATH. `java`
must be 21+ and node 20.19+. On an nvm node 20.11 shadowing the pinned one,
things fail in ways that read like the code being broken and are not.
### And the browser one
Step 5's done-criterion is a PICTURE, and no assertion in `cljs.test` can check
one: a take that resolves to the right numbers and draws nothing would pass every
test in `arthur.flow.freeze-test` . A blank canvas under a perfectly correct
transport is the bug class unit tests miss, and it has happened here once.
So there is a second suite that drives a real Chrome over CDP. It needs the dev
server up:
```sh
cd frontend & & mise exec -- npx shadow-cljs watch app # in one shell
cd frontend & & mise exec -- npm run browser # in another
```
No dependencies. Playwright is not installed and CDP needs none —
`node --experimental-websocket` has a global `WebSocket` and
`--headless=new --remote-debugging-port=N` is the whole of the other side. It
reads the canvas's own pixels rather than a screenshot, because the CSS scales
the stage up by 2 and a screenshot is four pixels per raster pixel; it writes
PNGs into `test/browser/out/` anyway, so "it drew something" can be checked by
eye as well as by count.
Port steps 2-3: the data model and the player
Steps 2 and 3 land together because the model revisions in the middle changed
code from both, and splitting them now would invent intermediate states that
never built.
domain/channel value-at across framed/keyed/dense, plus a cursor
domain/node decomposed transform, composition order, time maps
domain/scene topological order, z paths, eval-frame and resolver
clock audio-clocked frame derivation, outside app-db
db/events/subs re-frame arrives; the playhead is document state
ui/player the rAF loop; reads, blits, dispatches (almost) nothing
ui/shell transport
133 tests, 1158 assertions. The scene plays at 30fps against audio, scrubs, and
runs at 1/4x through 4x; verified by driving a real browser over CDP rather than
by assertion.
Two evaluators, on purpose. `eval-frame` is the specification -- allocating,
order-free, obviously correct. `resolver` is what playback uses: cached topo
order and z paths, a cursor per channel, a preallocated point buffer per node.
Both run the same walk, parameterised only by how a channel is read and where
points are written, because two independent implementations of frame evaluation
would drift and the drift would read as a rendering bug rather than as two
functions disagreeing. scene-test asserts they agree frame for frame in forward,
backward and random order.
Deviations and decisions, each with a reason:
- raster/fill-poly! is now a thin wrapper over fill-poly-buf!, which takes a flat
preallocated buffer. ONE scanline fill serves the analysis stages, which speak
{:x :y}, and frame evaluation, which hands over a buffer it owns. The parity
suite still passes pixel-for-pixel, which is what makes the rewrite safe.
- The state mask carries ABSENCE ONLY. An earlier draft gave it a hidden bit too,
per architecture.md's "hidden flag + palette index", and that bit was a dense
[:vis] wearing a different hat -- two mechanisms for one question, which is how
a part ends up hidden by one and shown by the other.
- The palette is a parameter of evaluation, not a global. A node names a TONE;
which ramp that tone is read in belongs to the timeline it sits in.
- :over layers and a symbol :rate THROW rather than being ignored. Neither is
built and nothing can produce one, so this can only fire on data that has run
ahead of the code. A silently dropped override is a hand correction the user
made once, watched fail, and has no reason to trust again.
Three findings the model produced rather than received:
- Presence propagates asymmetrically. An absent transform drops the subtree; an
absent [:geom :pts] drops only that node, because an absent mouth outline has
nothing to draw but the head it hangs off has not moved. That asymmetry is the
reason presence is tracked per channel and not per node.
- Z paths need lexicographic compare, not `compare`, which orders vectors by
count first -- so a cel three levels under "a1" would jump in front of a bare
"a2" and the layer order would mostly work.
- A node stencilled by something that drew nothing is dropped, not drawn
unclipped: an iris floating over the cheek is worse than a missing iris.
docs/ revised alongside, and those revisions are the load-bearing part:
- A scene, a timeline and a symbol are one type. The doc had two structures with
the same fields and never said so. Two axes of nesting are now separated --
parent/child within a timeline is flat with parent pointers, instance nesting
is by reference -- which is why "nestable" and "flat" only sounded
contradictory.
- Palettes are named, live on the project, and are ENABLED on a timeline as a
channel. Absent inherits; present travels with the timeline, so a symbol
authored against :night stays night wherever it is placed. The output index
space is the concatenation of the named ramps, which keeps one buffer and one
flat table and incidentally stops two nodes in different palettes colliding on
a stencil.
- Stabilisation is a channel, not a mode: {s, theta, tx, ty} IS [:xform :*], so
the normalise on/off/per-plate toggle is which of the three channel shapes the
:head node carries. Always measure and always store factored -- smoothing and
velocity-minimum key selection both need the split to exist in storage.
- There is no camera node and none is needed. Placement is a node transform, the
stage clips what hangs off it, and project dimensions are independent of the
footage. `makeXform` is therefore not to be ported: it bakes a cropping
decision into every stored vertex.
- Export is removed. The .take writer was for an Animator Pro render script; the
target is encoding video in the browser, and step 9 now says not to port the
old one.
demo/swarm is 120 shapes on six orbits, entirely dense blocks behind store
handles -- the shape freeze produces at step 5, and the first thing to exercise
that path under load. It plays at 30fps, and bench-test keeps a deliberately
loose floor under it because a performance regression here does not announce
itself: the picture stays correct and merely arrives late.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PDfHGdV39zu6rvgbBTfDaT
2026-09-27 17:28:05 -04:00
Port steps 0-1: scaffold, the oracle, and the pure bottom
Scaffolds frontend/ (shadow-cljs, reagent 1.2.0, re-frame 1.4.3) and ports
everything below the data model, with the JS kept as a numeric oracle.
domain/landmarks index tables, verbatim
domain/ring subsample, offset, simplicity
domain/geom similarity fit, procrustes, moving average
domain/raster indexed scanline fill, stencil, disc, rect
domain/palette the ramp, and the no-sampled-RGB rule
58 tests, 166 assertions. Parity with js/ on the identical 72-frame synthetic
track: fit-similarity, procrustes-mean, fit-residual, moving-average,
smooth-transforms, offset-ring and subsample-slots to 1e-9; the raster
pixel-for-pixel over the whole buffer.
Three deviations from the JS, each for a reason:
- synth.cljs jitters from a SEEDED generator, not Math.random. Parity is only
checkable if both sides can be handed the same track, and a failing assertion
has to be reproducible. `:rand-fn` takes the generator over, so oracle.mjs
stubs js/Math.random and js/ itself stays untouched.
- raster/->rgba replaces toImageData. ImageData is a DOM type and domain/ may
not touch the DOM; returning plain bytes also lets the
no-intermediate-colours assertion run in node. ui/canvas wraps it later.
- offset-ring lives in domain/ring, not domain/geom, per architecture.md: it is
an operation on an ordered traversal, not on a transform.
Step 1's "done" also names the swapped-iris vote, but pairIrises is in
pipeline.js and belongs to step 7. The precondition is asserted instead --
`:swap-iris` really does move both blocks -- so the vote will have a track that
disagrees with it when it arrives.
One finding, recorded in full in the test that measures it: smooth-transforms
buys nothing on the synthetic track. Against jitter-free ground truth, radius 1
helps by 17% on one noise realisation and hurts by 0.5% on another, so its
benefit is within noise; from radius 2 up the cost is unambiguous, and by radius
5 the filter is below the true motion's own high-frequency energy, i.e.
smoothing away performance. The test pins the shape of the knob rather than a
preferred value. This may say more about the synth's jitter being unrealistically
small (+/-0.001 normalised) than about the knob; step 6 settles it on real
footage.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-27 14:43:34 -04:00
## The app
```sh
2026-09-27 19:01:39 -04:00
cd frontend & & mise exec -- npx shadow-cljs watch app
Port steps 0-1: scaffold, the oracle, and the pure bottom
Scaffolds frontend/ (shadow-cljs, reagent 1.2.0, re-frame 1.4.3) and ports
everything below the data model, with the JS kept as a numeric oracle.
domain/landmarks index tables, verbatim
domain/ring subsample, offset, simplicity
domain/geom similarity fit, procrustes, moving average
domain/raster indexed scanline fill, stencil, disc, rect
domain/palette the ramp, and the no-sampled-RGB rule
58 tests, 166 assertions. Parity with js/ on the identical 72-frame synthetic
track: fit-similarity, procrustes-mean, fit-residual, moving-average,
smooth-transforms, offset-ring and subsample-slots to 1e-9; the raster
pixel-for-pixel over the whole buffer.
Three deviations from the JS, each for a reason:
- synth.cljs jitters from a SEEDED generator, not Math.random. Parity is only
checkable if both sides can be handed the same track, and a failing assertion
has to be reproducible. `:rand-fn` takes the generator over, so oracle.mjs
stubs js/Math.random and js/ itself stays untouched.
- raster/->rgba replaces toImageData. ImageData is a DOM type and domain/ may
not touch the DOM; returning plain bytes also lets the
no-intermediate-colours assertion run in node. ui/canvas wraps it later.
- offset-ring lives in domain/ring, not domain/geom, per architecture.md: it is
an operation on an ordered traversal, not on a transform.
Step 1's "done" also names the swapped-iris vote, but pairIrises is in
pipeline.js and belongs to step 7. The precondition is asserted instead --
`:swap-iris` really does move both blocks -- so the vote will have a track that
disagrees with it when it arrives.
One finding, recorded in full in the test that measures it: smooth-transforms
buys nothing on the synthetic track. Against jitter-free ground truth, radius 1
helps by 17% on one noise realisation and hurts by 0.5% on another, so its
benefit is within noise; from radius 2 up the cost is unambiguous, and by radius
5 the filter is below the true motion's own high-frequency energy, i.e.
smoothing away performance. The test pins the shape of the knob rather than a
preferred value. This may say more about the synth's jitter being unrealistically
small (+/-0.001 normalised) than about the knob; step 6 settles it on real
footage.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-27 14:43:34 -04:00
```
Then open ** < http: // localhost:8778 / index . html > ** — with the `/index.html` , not
bare `/` . This shadow-cljs does no directory-index resolution, so `/` is a 404
whatever the roots are.
2026-09-27 19:01:39 -04:00
Four clips, on buttons in the transport:
| | |
| --- | --- |
| `take` | the synthetic take, head **as filmed** . Step 5's deliverable: a moving mouth, frozen into dense channels, with no video file anywhere. |
| `locked` | the same freeze, head **locked** . The same blocks — `:head` 's channels are written as framed identity instead of as a dense track, and nothing in tier 2 differs. |
| `demo` | the hand-written scene from step 2. Not a face: the smallest scene that exercises every mechanism the model claims to have, so that each one is visible when it breaks. |
| `swarm` | a hundred and twenty dense nodes. Not useful; it is the load test. |
Port steps 2-3: the data model and the player
Steps 2 and 3 land together because the model revisions in the middle changed
code from both, and splitting them now would invent intermediate states that
never built.
domain/channel value-at across framed/keyed/dense, plus a cursor
domain/node decomposed transform, composition order, time maps
domain/scene topological order, z paths, eval-frame and resolver
clock audio-clocked frame derivation, outside app-db
db/events/subs re-frame arrives; the playhead is document state
ui/player the rAF loop; reads, blits, dispatches (almost) nothing
ui/shell transport
133 tests, 1158 assertions. The scene plays at 30fps against audio, scrubs, and
runs at 1/4x through 4x; verified by driving a real browser over CDP rather than
by assertion.
Two evaluators, on purpose. `eval-frame` is the specification -- allocating,
order-free, obviously correct. `resolver` is what playback uses: cached topo
order and z paths, a cursor per channel, a preallocated point buffer per node.
Both run the same walk, parameterised only by how a channel is read and where
points are written, because two independent implementations of frame evaluation
would drift and the drift would read as a rendering bug rather than as two
functions disagreeing. scene-test asserts they agree frame for frame in forward,
backward and random order.
Deviations and decisions, each with a reason:
- raster/fill-poly! is now a thin wrapper over fill-poly-buf!, which takes a flat
preallocated buffer. ONE scanline fill serves the analysis stages, which speak
{:x :y}, and frame evaluation, which hands over a buffer it owns. The parity
suite still passes pixel-for-pixel, which is what makes the rewrite safe.
- The state mask carries ABSENCE ONLY. An earlier draft gave it a hidden bit too,
per architecture.md's "hidden flag + palette index", and that bit was a dense
[:vis] wearing a different hat -- two mechanisms for one question, which is how
a part ends up hidden by one and shown by the other.
- The palette is a parameter of evaluation, not a global. A node names a TONE;
which ramp that tone is read in belongs to the timeline it sits in.
- :over layers and a symbol :rate THROW rather than being ignored. Neither is
built and nothing can produce one, so this can only fire on data that has run
ahead of the code. A silently dropped override is a hand correction the user
made once, watched fail, and has no reason to trust again.
Three findings the model produced rather than received:
- Presence propagates asymmetrically. An absent transform drops the subtree; an
absent [:geom :pts] drops only that node, because an absent mouth outline has
nothing to draw but the head it hangs off has not moved. That asymmetry is the
reason presence is tracked per channel and not per node.
- Z paths need lexicographic compare, not `compare`, which orders vectors by
count first -- so a cel three levels under "a1" would jump in front of a bare
"a2" and the layer order would mostly work.
- A node stencilled by something that drew nothing is dropped, not drawn
unclipped: an iris floating over the cheek is worse than a missing iris.
docs/ revised alongside, and those revisions are the load-bearing part:
- A scene, a timeline and a symbol are one type. The doc had two structures with
the same fields and never said so. Two axes of nesting are now separated --
parent/child within a timeline is flat with parent pointers, instance nesting
is by reference -- which is why "nestable" and "flat" only sounded
contradictory.
- Palettes are named, live on the project, and are ENABLED on a timeline as a
channel. Absent inherits; present travels with the timeline, so a symbol
authored against :night stays night wherever it is placed. The output index
space is the concatenation of the named ramps, which keeps one buffer and one
flat table and incidentally stops two nodes in different palettes colliding on
a stencil.
- Stabilisation is a channel, not a mode: {s, theta, tx, ty} IS [:xform :*], so
the normalise on/off/per-plate toggle is which of the three channel shapes the
:head node carries. Always measure and always store factored -- smoothing and
velocity-minimum key selection both need the split to exist in storage.
- There is no camera node and none is needed. Placement is a node transform, the
stage clips what hangs off it, and project dimensions are independent of the
footage. `makeXform` is therefore not to be ported: it bakes a cropping
decision into every stored vertex.
- Export is removed. The .take writer was for an Animator Pro render script; the
target is encoding video in the browser, and step 9 now says not to port the
old one.
demo/swarm is 120 shapes on six orbits, entirely dense blocks behind store
handles -- the shape freeze produces at step 5, and the first thing to exercise
that path under load. It plays at 30fps, and bench-test keeps a deliberately
loose floor under it because a performance regression here does not announce
itself: the picture stays correct and merely arrives late.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PDfHGdV39zu6rvgbBTfDaT
2026-09-27 17:28:05 -04:00
2026-09-27 19:01:39 -04:00
`take` and `locked` are the pair worth looking at together, because switching
between them is the whole of what "stabilisation is a channel, not a mode" means.
The demo scene itself is `src/arthur/demo/scene.edn` ; the take is built in
`src/arthur/demo/take.cljs` , which is also the only place the seven stages are
composed in order.
Port steps 0-1: scaffold, the oracle, and the pure bottom
Scaffolds frontend/ (shadow-cljs, reagent 1.2.0, re-frame 1.4.3) and ports
everything below the data model, with the JS kept as a numeric oracle.
domain/landmarks index tables, verbatim
domain/ring subsample, offset, simplicity
domain/geom similarity fit, procrustes, moving average
domain/raster indexed scanline fill, stencil, disc, rect
domain/palette the ramp, and the no-sampled-RGB rule
58 tests, 166 assertions. Parity with js/ on the identical 72-frame synthetic
track: fit-similarity, procrustes-mean, fit-residual, moving-average,
smooth-transforms, offset-ring and subsample-slots to 1e-9; the raster
pixel-for-pixel over the whole buffer.
Three deviations from the JS, each for a reason:
- synth.cljs jitters from a SEEDED generator, not Math.random. Parity is only
checkable if both sides can be handed the same track, and a failing assertion
has to be reproducible. `:rand-fn` takes the generator over, so oracle.mjs
stubs js/Math.random and js/ itself stays untouched.
- raster/->rgba replaces toImageData. ImageData is a DOM type and domain/ may
not touch the DOM; returning plain bytes also lets the
no-intermediate-colours assertion run in node. ui/canvas wraps it later.
- offset-ring lives in domain/ring, not domain/geom, per architecture.md: it is
an operation on an ordered traversal, not on a transform.
Step 1's "done" also names the swapped-iris vote, but pairIrises is in
pipeline.js and belongs to step 7. The precondition is asserted instead --
`:swap-iris` really does move both blocks -- so the vote will have a track that
disagrees with it when it arrives.
One finding, recorded in full in the test that measures it: smooth-transforms
buys nothing on the synthetic track. Against jitter-free ground truth, radius 1
helps by 17% on one noise realisation and hurts by 0.5% on another, so its
benefit is within noise; from radius 2 up the cost is unambiguous, and by radius
5 the filter is below the true motion's own high-frequency energy, i.e.
smoothing away performance. The test pins the shape of the knob rather than a
preferred value. This may say more about the synth's jitter being unrealistically
small (+/-0.001 normalised) than about the knob; step 6 settles it on real
footage.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-27 14:43:34 -04:00
Port 8778 is deliberately not 8777. `python3 serve.py` from the repo root still
2026-09-27 19:01:39 -04:00
runs the old JS tool on 8777, and the two are meant to run side by side.
Port steps 0-1: scaffold, the oracle, and the pure bottom
Scaffolds frontend/ (shadow-cljs, reagent 1.2.0, re-frame 1.4.3) and ports
everything below the data model, with the JS kept as a numeric oracle.
domain/landmarks index tables, verbatim
domain/ring subsample, offset, simplicity
domain/geom similarity fit, procrustes, moving average
domain/raster indexed scanline fill, stencil, disc, rect
domain/palette the ramp, and the no-sampled-RGB rule
58 tests, 166 assertions. Parity with js/ on the identical 72-frame synthetic
track: fit-similarity, procrustes-mean, fit-residual, moving-average,
smooth-transforms, offset-ring and subsample-slots to 1e-9; the raster
pixel-for-pixel over the whole buffer.
Three deviations from the JS, each for a reason:
- synth.cljs jitters from a SEEDED generator, not Math.random. Parity is only
checkable if both sides can be handed the same track, and a failing assertion
has to be reproducible. `:rand-fn` takes the generator over, so oracle.mjs
stubs js/Math.random and js/ itself stays untouched.
- raster/->rgba replaces toImageData. ImageData is a DOM type and domain/ may
not touch the DOM; returning plain bytes also lets the
no-intermediate-colours assertion run in node. ui/canvas wraps it later.
- offset-ring lives in domain/ring, not domain/geom, per architecture.md: it is
an operation on an ordered traversal, not on a transform.
Step 1's "done" also names the swapped-iris vote, but pairIrises is in
pipeline.js and belongs to step 7. The precondition is asserted instead --
`:swap-iris` really does move both blocks -- so the vote will have a track that
disagrees with it when it arrives.
One finding, recorded in full in the test that measures it: smooth-transforms
buys nothing on the synthetic track. Against jitter-free ground truth, radius 1
helps by 17% on one noise realisation and hurts by 0.5% on another, so its
benefit is within noise; from radius 2 up the cost is unambiguous, and by radius
5 the filter is below the true motion's own high-frequency energy, i.e.
smoothing away performance. The test pins the shape of the knob rather than a
preferred value. This may say more about the synth's jitter being unrealistically
small (+/-0.001 normalised) than about the knob; step 6 settles it on real
footage.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-27 14:43:34 -04:00
From step 9 Django serves the page and `:dev-http` goes away.
2026-09-27 19:01:39 -04:00
## The oracle, which is finished
Port step 4: measure the anchor and the mouth, condition on its own
`stabilize` is three things wearing one name, and it is now three functions in two
stages: `flow/measure/anchor` fits the rigid transform, `flow/condition` smooths
its parameters, `flow/measure/mouth` measures the lip rings through the result.
Parity is on the COMPOSITION and not on the pieces -- a split that agreed
function by function and not end to end would be a split rather than a port.
The oracle now drives `stabilize` at three configurations and the port agrees to
1e-9 on ref, rigid, transforms, outer, inner and aperture, plus `smoothContours`
at three radii. Two of the three configurations are at aspect 0.5625, a 1080x1920
phone clip, because at aspect 1 `pick` is the identity: a port that dropped the
anisotropy correction outright would pass every other assertion in the suite.
148 tests, up from 134.
Three decisions worth the reading time.
`makeXform` is not ported, and its absence takes the face oval with it. It
centres on the oval's bounding box and zooms until the face is 80% of the raster
height, so every vertex it touched carried a cropping decision made once, at
analysis time, from one frame's landmarks. Geometry belongs in the node's own
local space with the framing as a transform on a node, so this is a deletion. The
oval's only other consumer was the placeholder plate outline, which is painting.
The residual is taken against the RAW fit, and the prototype took it against the
smoothed one. That is the only deliberate numeric divergence here, and parity is
kept by asserting `anchor/residuals` on exactly what the prototype handed it. The
number's job is to say whether a section is stabilisable at all; folding the
smoothing error into it makes a slider look like a property of the footage, and
docs/architecture.md lists the residual under stage 3, which requires it to be
knob-free. `condition/anchor` therefore replaces `:transforms` and leaves
`:residual` alone.
The stage order is not the strict chain the table in docs/architecture.md looks
like, and that document now says so. The fit is knob-free, conditioning smooths
it, and the rings are measured *through* the conditioned transform -- so
`anchor avg` does re-run the ring mapping, which is a few hundred frames of twenty
points. The guarantee was only ever about the part that reads a source pixel, and
that part never sees a transform.
Two things fall out and are asserted rather than assumed. Smoothing and
subsampling commute, because both are per-slot, which is what lets `vertices`
stay a stage-5 knob downstream of a stage-4 one -- and it is also why the port can
smooth the full twenty slots where the prototype smooths eight and still match.
And `condition/contours` is `geom/moving-average` per vertex per axis rather than
its own clamped window, so "radius 2" cannot come to mean two different things at
the two knobs.
One dead end recorded so nobody walks it twice: the synth's head is perfectly
rigid -- its jitter is a whole-head translation, which a similarity absorbs
exactly -- so every frame's rigid configuration is congruent with frame zero's and
the Procrustes mean IS frame zero to 1e-15, jitter or none. "The reference is the
mean and not frame zero" cannot be asserted on this track and is asserted in
geom-test, where the two can differ.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-27 18:00:11 -04:00
2026-09-27 19:01:39 -04:00
`js/` was the numeric oracle through step 4: `test/parity/` ran both
implementations on the same synthetic track and diffed `fit-similarity` ,
`procrustes-mean` , the raster and `stabilize` to 1e-9.
Port steps 0-1: scaffold, the oracle, and the pure bottom
Scaffolds frontend/ (shadow-cljs, reagent 1.2.0, re-frame 1.4.3) and ports
everything below the data model, with the JS kept as a numeric oracle.
domain/landmarks index tables, verbatim
domain/ring subsample, offset, simplicity
domain/geom similarity fit, procrustes, moving average
domain/raster indexed scanline fill, stencil, disc, rect
domain/palette the ramp, and the no-sampled-RGB rule
58 tests, 166 assertions. Parity with js/ on the identical 72-frame synthetic
track: fit-similarity, procrustes-mean, fit-residual, moving-average,
smooth-transforms, offset-ring and subsample-slots to 1e-9; the raster
pixel-for-pixel over the whole buffer.
Three deviations from the JS, each for a reason:
- synth.cljs jitters from a SEEDED generator, not Math.random. Parity is only
checkable if both sides can be handed the same track, and a failing assertion
has to be reproducible. `:rand-fn` takes the generator over, so oracle.mjs
stubs js/Math.random and js/ itself stays untouched.
- raster/->rgba replaces toImageData. ImageData is a DOM type and domain/ may
not touch the DOM; returning plain bytes also lets the
no-intermediate-colours assertion run in node. ui/canvas wraps it later.
- offset-ring lives in domain/ring, not domain/geom, per architecture.md: it is
an operation on an ordered traversal, not on a transform.
Step 1's "done" also names the swapped-iris vote, but pairIrises is in
pipeline.js and belongs to step 7. The precondition is asserted instead --
`:swap-iris` really does move both blocks -- so the vote will have a track that
disagrees with it when it arrives.
One finding, recorded in full in the test that measures it: smooth-transforms
buys nothing on the synthetic track. Against jitter-free ground truth, radius 1
helps by 17% on one noise realisation and hurts by 0.5% on another, so its
benefit is within noise; from radius 2 up the cost is unambiguous, and by radius
5 the filter is below the true motion's own high-frequency energy, i.e.
smoothing away performance. The test pins the shape of the knob rather than a
preferred value. This may say more about the synth's jitter being unrealistically
small (+/-0.001 normalised) than about the knob; step 6 settles it on real
footage.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-27 14:43:34 -04:00
2026-09-27 19:01:39 -04:00
**It was deleted at step 5, on purpose.** Parity proves the port is FAITHFUL, not
that the answer is RIGHT. The JS is a prototype and several of its conclusions
contradict each other; a parity test pins behaviour while code moves, and keeping
it afterwards would bake the prototype's mistakes into the rewrite and make them
permanent. `docs/port-plan.md` says to delete it in one commit once the CLJS
player renders the synthetic take, and that is what happened.
Port steps 0-1: scaffold, the oracle, and the pure bottom
Scaffolds frontend/ (shadow-cljs, reagent 1.2.0, re-frame 1.4.3) and ports
everything below the data model, with the JS kept as a numeric oracle.
domain/landmarks index tables, verbatim
domain/ring subsample, offset, simplicity
domain/geom similarity fit, procrustes, moving average
domain/raster indexed scanline fill, stencil, disc, rect
domain/palette the ramp, and the no-sampled-RGB rule
58 tests, 166 assertions. Parity with js/ on the identical 72-frame synthetic
track: fit-similarity, procrustes-mean, fit-residual, moving-average,
smooth-transforms, offset-ring and subsample-slots to 1e-9; the raster
pixel-for-pixel over the whole buffer.
Three deviations from the JS, each for a reason:
- synth.cljs jitters from a SEEDED generator, not Math.random. Parity is only
checkable if both sides can be handed the same track, and a failing assertion
has to be reproducible. `:rand-fn` takes the generator over, so oracle.mjs
stubs js/Math.random and js/ itself stays untouched.
- raster/->rgba replaces toImageData. ImageData is a DOM type and domain/ may
not touch the DOM; returning plain bytes also lets the
no-intermediate-colours assertion run in node. ui/canvas wraps it later.
- offset-ring lives in domain/ring, not domain/geom, per architecture.md: it is
an operation on an ordered traversal, not on a transform.
Step 1's "done" also names the swapped-iris vote, but pairIrises is in
pipeline.js and belongs to step 7. The precondition is asserted instead --
`:swap-iris` really does move both blocks -- so the vote will have a track that
disagrees with it when it arrives.
One finding, recorded in full in the test that measures it: smooth-transforms
buys nothing on the synthetic track. Against jitter-free ground truth, radius 1
helps by 17% on one noise realisation and hurts by 0.5% on another, so its
benefit is within noise; from radius 2 up the cost is unambiguous, and by radius
5 the filter is below the true motion's own high-frequency energy, i.e.
smoothing away performance. The test pins the shape of the knob rather than a
preferred value. This may say more about the synth's jitter being unrealistically
small (+/-0.001 normalised) than about the knob; step 6 settles it on real
footage.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-27 14:43:34 -04:00
2026-09-27 19:01:39 -04:00
`js/` itself stays. It is not an oracle any more, it is the SOURCE for steps 6
and 7 — the MediaPipe setup, the eye and brow signals, the interior extraction —
and its comments encode bugs that actually happened.
Port steps 0-1: scaffold, the oracle, and the pure bottom
Scaffolds frontend/ (shadow-cljs, reagent 1.2.0, re-frame 1.4.3) and ports
everything below the data model, with the JS kept as a numeric oracle.
domain/landmarks index tables, verbatim
domain/ring subsample, offset, simplicity
domain/geom similarity fit, procrustes, moving average
domain/raster indexed scanline fill, stencil, disc, rect
domain/palette the ramp, and the no-sampled-RGB rule
58 tests, 166 assertions. Parity with js/ on the identical 72-frame synthetic
track: fit-similarity, procrustes-mean, fit-residual, moving-average,
smooth-transforms, offset-ring and subsample-slots to 1e-9; the raster
pixel-for-pixel over the whole buffer.
Three deviations from the JS, each for a reason:
- synth.cljs jitters from a SEEDED generator, not Math.random. Parity is only
checkable if both sides can be handed the same track, and a failing assertion
has to be reproducible. `:rand-fn` takes the generator over, so oracle.mjs
stubs js/Math.random and js/ itself stays untouched.
- raster/->rgba replaces toImageData. ImageData is a DOM type and domain/ may
not touch the DOM; returning plain bytes also lets the
no-intermediate-colours assertion run in node. ui/canvas wraps it later.
- offset-ring lives in domain/ring, not domain/geom, per architecture.md: it is
an operation on an ordered traversal, not on a transform.
Step 1's "done" also names the swapped-iris vote, but pairIrises is in
pipeline.js and belongs to step 7. The precondition is asserted instead --
`:swap-iris` really does move both blocks -- so the vote will have a track that
disagrees with it when it arrives.
One finding, recorded in full in the test that measures it: smooth-transforms
buys nothing on the synthetic track. Against jitter-free ground truth, radius 1
helps by 17% on one noise realisation and hurts by 0.5% on another, so its
benefit is within noise; from radius 2 up the cost is unambiguous, and by radius
5 the filter is below the true motion's own high-frequency energy, i.e.
smoothing away performance. The test pins the shape of the knob rather than a
preferred value. This may say more about the synth's jitter being unrealistically
small (+/-0.001 normalised) than about the knob; step 6 settles it on real
footage.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-27 14:43:34 -04:00
## Layout
```
Port steps 2-3: the data model and the player
Steps 2 and 3 land together because the model revisions in the middle changed
code from both, and splitting them now would invent intermediate states that
never built.
domain/channel value-at across framed/keyed/dense, plus a cursor
domain/node decomposed transform, composition order, time maps
domain/scene topological order, z paths, eval-frame and resolver
clock audio-clocked frame derivation, outside app-db
db/events/subs re-frame arrives; the playhead is document state
ui/player the rAF loop; reads, blits, dispatches (almost) nothing
ui/shell transport
133 tests, 1158 assertions. The scene plays at 30fps against audio, scrubs, and
runs at 1/4x through 4x; verified by driving a real browser over CDP rather than
by assertion.
Two evaluators, on purpose. `eval-frame` is the specification -- allocating,
order-free, obviously correct. `resolver` is what playback uses: cached topo
order and z paths, a cursor per channel, a preallocated point buffer per node.
Both run the same walk, parameterised only by how a channel is read and where
points are written, because two independent implementations of frame evaluation
would drift and the drift would read as a rendering bug rather than as two
functions disagreeing. scene-test asserts they agree frame for frame in forward,
backward and random order.
Deviations and decisions, each with a reason:
- raster/fill-poly! is now a thin wrapper over fill-poly-buf!, which takes a flat
preallocated buffer. ONE scanline fill serves the analysis stages, which speak
{:x :y}, and frame evaluation, which hands over a buffer it owns. The parity
suite still passes pixel-for-pixel, which is what makes the rewrite safe.
- The state mask carries ABSENCE ONLY. An earlier draft gave it a hidden bit too,
per architecture.md's "hidden flag + palette index", and that bit was a dense
[:vis] wearing a different hat -- two mechanisms for one question, which is how
a part ends up hidden by one and shown by the other.
- The palette is a parameter of evaluation, not a global. A node names a TONE;
which ramp that tone is read in belongs to the timeline it sits in.
- :over layers and a symbol :rate THROW rather than being ignored. Neither is
built and nothing can produce one, so this can only fire on data that has run
ahead of the code. A silently dropped override is a hand correction the user
made once, watched fail, and has no reason to trust again.
Three findings the model produced rather than received:
- Presence propagates asymmetrically. An absent transform drops the subtree; an
absent [:geom :pts] drops only that node, because an absent mouth outline has
nothing to draw but the head it hangs off has not moved. That asymmetry is the
reason presence is tracked per channel and not per node.
- Z paths need lexicographic compare, not `compare`, which orders vectors by
count first -- so a cel three levels under "a1" would jump in front of a bare
"a2" and the layer order would mostly work.
- A node stencilled by something that drew nothing is dropped, not drawn
unclipped: an iris floating over the cheek is worse than a missing iris.
docs/ revised alongside, and those revisions are the load-bearing part:
- A scene, a timeline and a symbol are one type. The doc had two structures with
the same fields and never said so. Two axes of nesting are now separated --
parent/child within a timeline is flat with parent pointers, instance nesting
is by reference -- which is why "nestable" and "flat" only sounded
contradictory.
- Palettes are named, live on the project, and are ENABLED on a timeline as a
channel. Absent inherits; present travels with the timeline, so a symbol
authored against :night stays night wherever it is placed. The output index
space is the concatenation of the named ramps, which keeps one buffer and one
flat table and incidentally stops two nodes in different palettes colliding on
a stencil.
- Stabilisation is a channel, not a mode: {s, theta, tx, ty} IS [:xform :*], so
the normalise on/off/per-plate toggle is which of the three channel shapes the
:head node carries. Always measure and always store factored -- smoothing and
velocity-minimum key selection both need the split to exist in storage.
- There is no camera node and none is needed. Placement is a node transform, the
stage clips what hangs off it, and project dimensions are independent of the
footage. `makeXform` is therefore not to be ported: it bakes a cropping
decision into every stored vertex.
- Export is removed. The .take writer was for an Animator Pro render script; the
target is encoding video in the browser, and step 9 now says not to port the
old one.
demo/swarm is 120 shapes on six orbits, entirely dense blocks behind store
handles -- the shape freeze produces at step 5, and the first thing to exercise
that path under load. It plays at 30fps, and bench-test keeps a deliberately
loose floor under it because a performance regression here does not announce
itself: the picture stays correct and merely arrives late.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PDfHGdV39zu6rvgbBTfDaT
2026-09-27 17:28:05 -04:00
src/arthur/domain/ pure. No re-frame, no DOM, no flow/.
Port step 4: measure the anchor and the mouth, condition on its own
`stabilize` is three things wearing one name, and it is now three functions in two
stages: `flow/measure/anchor` fits the rigid transform, `flow/condition` smooths
its parameters, `flow/measure/mouth` measures the lip rings through the result.
Parity is on the COMPOSITION and not on the pieces -- a split that agreed
function by function and not end to end would be a split rather than a port.
The oracle now drives `stabilize` at three configurations and the port agrees to
1e-9 on ref, rigid, transforms, outer, inner and aperture, plus `smoothContours`
at three radii. Two of the three configurations are at aspect 0.5625, a 1080x1920
phone clip, because at aspect 1 `pick` is the identity: a port that dropped the
anisotropy correction outright would pass every other assertion in the suite.
148 tests, up from 134.
Three decisions worth the reading time.
`makeXform` is not ported, and its absence takes the face oval with it. It
centres on the oval's bounding box and zooms until the face is 80% of the raster
height, so every vertex it touched carried a cropping decision made once, at
analysis time, from one frame's landmarks. Geometry belongs in the node's own
local space with the framing as a transform on a node, so this is a deletion. The
oval's only other consumer was the placeholder plate outline, which is painting.
The residual is taken against the RAW fit, and the prototype took it against the
smoothed one. That is the only deliberate numeric divergence here, and parity is
kept by asserting `anchor/residuals` on exactly what the prototype handed it. The
number's job is to say whether a section is stabilisable at all; folding the
smoothing error into it makes a slider look like a property of the footage, and
docs/architecture.md lists the residual under stage 3, which requires it to be
knob-free. `condition/anchor` therefore replaces `:transforms` and leaves
`:residual` alone.
The stage order is not the strict chain the table in docs/architecture.md looks
like, and that document now says so. The fit is knob-free, conditioning smooths
it, and the rings are measured *through* the conditioned transform -- so
`anchor avg` does re-run the ring mapping, which is a few hundred frames of twenty
points. The guarantee was only ever about the part that reads a source pixel, and
that part never sees a transform.
Two things fall out and are asserted rather than assumed. Smoothing and
subsampling commute, because both are per-slot, which is what lets `vertices`
stay a stage-5 knob downstream of a stage-4 one -- and it is also why the port can
smooth the full twenty slots where the prototype smooths eight and still match.
And `condition/contours` is `geom/moving-average` per vertex per axis rather than
its own clamped window, so "radius 2" cannot come to mean two different things at
the two knobs.
One dead end recorded so nobody walks it twice: the synth's head is perfectly
rigid -- its jitter is a whole-head translation, which a similarity absorbs
exactly -- so every frame's rigid configuration is congruent with frame zero's and
the Procrustes mean IS frame zero to 1e-15, jitter or none. "The reference is the
mean and not frame zero" cannot be asserted on this track and is asserted in
geom-test, where the two can differ.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-27 18:00:11 -04:00
src/arthur/flow/ the stages. `(f params inputs) -> output` , no state.
2026-09-27 19:01:39 -04:00
src/arthur/synth.cljs the synthetic track. In src/ because the take PLAYS it —
it stands in for flow/detect, and a tool that needs a
video file before it shows you anything is one you
cannot debug.
Port steps 2-3: the data model and the player
Steps 2 and 3 land together because the model revisions in the middle changed
code from both, and splitting them now would invent intermediate states that
never built.
domain/channel value-at across framed/keyed/dense, plus a cursor
domain/node decomposed transform, composition order, time maps
domain/scene topological order, z paths, eval-frame and resolver
clock audio-clocked frame derivation, outside app-db
db/events/subs re-frame arrives; the playhead is document state
ui/player the rAF loop; reads, blits, dispatches (almost) nothing
ui/shell transport
133 tests, 1158 assertions. The scene plays at 30fps against audio, scrubs, and
runs at 1/4x through 4x; verified by driving a real browser over CDP rather than
by assertion.
Two evaluators, on purpose. `eval-frame` is the specification -- allocating,
order-free, obviously correct. `resolver` is what playback uses: cached topo
order and z paths, a cursor per channel, a preallocated point buffer per node.
Both run the same walk, parameterised only by how a channel is read and where
points are written, because two independent implementations of frame evaluation
would drift and the drift would read as a rendering bug rather than as two
functions disagreeing. scene-test asserts they agree frame for frame in forward,
backward and random order.
Deviations and decisions, each with a reason:
- raster/fill-poly! is now a thin wrapper over fill-poly-buf!, which takes a flat
preallocated buffer. ONE scanline fill serves the analysis stages, which speak
{:x :y}, and frame evaluation, which hands over a buffer it owns. The parity
suite still passes pixel-for-pixel, which is what makes the rewrite safe.
- The state mask carries ABSENCE ONLY. An earlier draft gave it a hidden bit too,
per architecture.md's "hidden flag + palette index", and that bit was a dense
[:vis] wearing a different hat -- two mechanisms for one question, which is how
a part ends up hidden by one and shown by the other.
- The palette is a parameter of evaluation, not a global. A node names a TONE;
which ramp that tone is read in belongs to the timeline it sits in.
- :over layers and a symbol :rate THROW rather than being ignored. Neither is
built and nothing can produce one, so this can only fire on data that has run
ahead of the code. A silently dropped override is a hand correction the user
made once, watched fail, and has no reason to trust again.
Three findings the model produced rather than received:
- Presence propagates asymmetrically. An absent transform drops the subtree; an
absent [:geom :pts] drops only that node, because an absent mouth outline has
nothing to draw but the head it hangs off has not moved. That asymmetry is the
reason presence is tracked per channel and not per node.
- Z paths need lexicographic compare, not `compare`, which orders vectors by
count first -- so a cel three levels under "a1" would jump in front of a bare
"a2" and the layer order would mostly work.
- A node stencilled by something that drew nothing is dropped, not drawn
unclipped: an iris floating over the cheek is worse than a missing iris.
docs/ revised alongside, and those revisions are the load-bearing part:
- A scene, a timeline and a symbol are one type. The doc had two structures with
the same fields and never said so. Two axes of nesting are now separated --
parent/child within a timeline is flat with parent pointers, instance nesting
is by reference -- which is why "nestable" and "flat" only sounded
contradictory.
- Palettes are named, live on the project, and are ENABLED on a timeline as a
channel. Absent inherits; present travels with the timeline, so a symbol
authored against :night stays night wherever it is placed. The output index
space is the concatenation of the named ramps, which keeps one buffer and one
flat table and incidentally stops two nodes in different palettes colliding on
a stencil.
- Stabilisation is a channel, not a mode: {s, theta, tx, ty} IS [:xform :*], so
the normalise on/off/per-plate toggle is which of the three channel shapes the
:head node carries. Always measure and always store factored -- smoothing and
velocity-minimum key selection both need the split to exist in storage.
- There is no camera node and none is needed. Placement is a node transform, the
stage clips what hangs off it, and project dimensions are independent of the
footage. `makeXform` is therefore not to be ported: it bakes a cropping
decision into every stored vertex.
- Export is removed. The .take writer was for an Animator Pro render script; the
target is encoding video in the browser, and step 9 now says not to port the
old one.
demo/swarm is 120 shapes on six orbits, entirely dense blocks behind store
handles -- the shape freeze produces at step 5, and the first thing to exercise
that path under load. It plays at 30fps, and bench-test keeps a deliberately
loose floor under it because a performance regression here does not announce
itself: the picture stays correct and merely arrives late.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PDfHGdV39zu6rvgbBTfDaT
2026-09-27 17:28:05 -04:00
src/arthur/demo.cljs the hand-written scene, read from demo/scene.edn
2026-09-27 19:01:39 -04:00
src/arthur/demo/take.cljs the seven stages composed in order, and the only place
they are
Port steps 2-3: the data model and the player
Steps 2 and 3 land together because the model revisions in the middle changed
code from both, and splitting them now would invent intermediate states that
never built.
domain/channel value-at across framed/keyed/dense, plus a cursor
domain/node decomposed transform, composition order, time maps
domain/scene topological order, z paths, eval-frame and resolver
clock audio-clocked frame derivation, outside app-db
db/events/subs re-frame arrives; the playhead is document state
ui/player the rAF loop; reads, blits, dispatches (almost) nothing
ui/shell transport
133 tests, 1158 assertions. The scene plays at 30fps against audio, scrubs, and
runs at 1/4x through 4x; verified by driving a real browser over CDP rather than
by assertion.
Two evaluators, on purpose. `eval-frame` is the specification -- allocating,
order-free, obviously correct. `resolver` is what playback uses: cached topo
order and z paths, a cursor per channel, a preallocated point buffer per node.
Both run the same walk, parameterised only by how a channel is read and where
points are written, because two independent implementations of frame evaluation
would drift and the drift would read as a rendering bug rather than as two
functions disagreeing. scene-test asserts they agree frame for frame in forward,
backward and random order.
Deviations and decisions, each with a reason:
- raster/fill-poly! is now a thin wrapper over fill-poly-buf!, which takes a flat
preallocated buffer. ONE scanline fill serves the analysis stages, which speak
{:x :y}, and frame evaluation, which hands over a buffer it owns. The parity
suite still passes pixel-for-pixel, which is what makes the rewrite safe.
- The state mask carries ABSENCE ONLY. An earlier draft gave it a hidden bit too,
per architecture.md's "hidden flag + palette index", and that bit was a dense
[:vis] wearing a different hat -- two mechanisms for one question, which is how
a part ends up hidden by one and shown by the other.
- The palette is a parameter of evaluation, not a global. A node names a TONE;
which ramp that tone is read in belongs to the timeline it sits in.
- :over layers and a symbol :rate THROW rather than being ignored. Neither is
built and nothing can produce one, so this can only fire on data that has run
ahead of the code. A silently dropped override is a hand correction the user
made once, watched fail, and has no reason to trust again.
Three findings the model produced rather than received:
- Presence propagates asymmetrically. An absent transform drops the subtree; an
absent [:geom :pts] drops only that node, because an absent mouth outline has
nothing to draw but the head it hangs off has not moved. That asymmetry is the
reason presence is tracked per channel and not per node.
- Z paths need lexicographic compare, not `compare`, which orders vectors by
count first -- so a cel three levels under "a1" would jump in front of a bare
"a2" and the layer order would mostly work.
- A node stencilled by something that drew nothing is dropped, not drawn
unclipped: an iris floating over the cheek is worse than a missing iris.
docs/ revised alongside, and those revisions are the load-bearing part:
- A scene, a timeline and a symbol are one type. The doc had two structures with
the same fields and never said so. Two axes of nesting are now separated --
parent/child within a timeline is flat with parent pointers, instance nesting
is by reference -- which is why "nestable" and "flat" only sounded
contradictory.
- Palettes are named, live on the project, and are ENABLED on a timeline as a
channel. Absent inherits; present travels with the timeline, so a symbol
authored against :night stays night wherever it is placed. The output index
space is the concatenation of the named ramps, which keeps one buffer and one
flat table and incidentally stops two nodes in different palettes colliding on
a stencil.
- Stabilisation is a channel, not a mode: {s, theta, tx, ty} IS [:xform :*], so
the normalise on/off/per-plate toggle is which of the three channel shapes the
:head node carries. Always measure and always store factored -- smoothing and
velocity-minimum key selection both need the split to exist in storage.
- There is no camera node and none is needed. Placement is a node transform, the
stage clips what hangs off it, and project dimensions are independent of the
footage. `makeXform` is therefore not to be ported: it bakes a cropping
decision into every stored vertex.
- Export is removed. The .take writer was for an Animator Pro render script; the
target is encoding video in the browser, and step 9 now says not to port the
old one.
demo/swarm is 120 shapes on six orbits, entirely dense blocks behind store
handles -- the shape freeze produces at step 5, and the first thing to exercise
that path under load. It plays at 30fps, and bench-test keeps a deliberately
loose floor under it because a performance regression here does not announce
itself: the picture stays correct and merely arrives late.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PDfHGdV39zu6rvgbBTfDaT
2026-09-27 17:28:05 -04:00
src/arthur/ui/canvas.cljs the one imperative sink — the only DOM canvas call
2026-09-27 19:01:39 -04:00
test/browser/ drives a real Chrome over CDP. Not run by `npm test` .
Port steps 0-1: scaffold, the oracle, and the pure bottom
Scaffolds frontend/ (shadow-cljs, reagent 1.2.0, re-frame 1.4.3) and ports
everything below the data model, with the JS kept as a numeric oracle.
domain/landmarks index tables, verbatim
domain/ring subsample, offset, simplicity
domain/geom similarity fit, procrustes, moving average
domain/raster indexed scanline fill, stencil, disc, rect
domain/palette the ramp, and the no-sampled-RGB rule
58 tests, 166 assertions. Parity with js/ on the identical 72-frame synthetic
track: fit-similarity, procrustes-mean, fit-residual, moving-average,
smooth-transforms, offset-ring and subsample-slots to 1e-9; the raster
pixel-for-pixel over the whole buffer.
Three deviations from the JS, each for a reason:
- synth.cljs jitters from a SEEDED generator, not Math.random. Parity is only
checkable if both sides can be handed the same track, and a failing assertion
has to be reproducible. `:rand-fn` takes the generator over, so oracle.mjs
stubs js/Math.random and js/ itself stays untouched.
- raster/->rgba replaces toImageData. ImageData is a DOM type and domain/ may
not touch the DOM; returning plain bytes also lets the
no-intermediate-colours assertion run in node. ui/canvas wraps it later.
- offset-ring lives in domain/ring, not domain/geom, per architecture.md: it is
an operation on an ordered traversal, not on a transform.
Step 1's "done" also names the swapped-iris vote, but pairIrises is in
pipeline.js and belongs to step 7. The precondition is asserted instead --
`:swap-iris` really does move both blocks -- so the vote will have a track that
disagrees with it when it arrives.
One finding, recorded in full in the test that measures it: smooth-transforms
buys nothing on the synthetic track. Against jitter-free ground truth, radius 1
helps by 17% on one noise realisation and hurts by 0.5% on another, so its
benefit is within noise; from radius 2 up the cost is unambiguous, and by radius
5 the filter is below the true motion's own high-frequency energy, i.e.
smoothing away performance. The test pins the shape of the knob rather than a
preferred value. This may say more about the synth's jitter being unrealistically
small (+/-0.001 normalised) than about the knob; step 6 settles it on real
footage.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-27 14:43:34 -04:00
public/index.html dev host page. Django replaces it at step 9.
```
Port steps 2-3: the data model and the player
Steps 2 and 3 land together because the model revisions in the middle changed
code from both, and splitting them now would invent intermediate states that
never built.
domain/channel value-at across framed/keyed/dense, plus a cursor
domain/node decomposed transform, composition order, time maps
domain/scene topological order, z paths, eval-frame and resolver
clock audio-clocked frame derivation, outside app-db
db/events/subs re-frame arrives; the playhead is document state
ui/player the rAF loop; reads, blits, dispatches (almost) nothing
ui/shell transport
133 tests, 1158 assertions. The scene plays at 30fps against audio, scrubs, and
runs at 1/4x through 4x; verified by driving a real browser over CDP rather than
by assertion.
Two evaluators, on purpose. `eval-frame` is the specification -- allocating,
order-free, obviously correct. `resolver` is what playback uses: cached topo
order and z paths, a cursor per channel, a preallocated point buffer per node.
Both run the same walk, parameterised only by how a channel is read and where
points are written, because two independent implementations of frame evaluation
would drift and the drift would read as a rendering bug rather than as two
functions disagreeing. scene-test asserts they agree frame for frame in forward,
backward and random order.
Deviations and decisions, each with a reason:
- raster/fill-poly! is now a thin wrapper over fill-poly-buf!, which takes a flat
preallocated buffer. ONE scanline fill serves the analysis stages, which speak
{:x :y}, and frame evaluation, which hands over a buffer it owns. The parity
suite still passes pixel-for-pixel, which is what makes the rewrite safe.
- The state mask carries ABSENCE ONLY. An earlier draft gave it a hidden bit too,
per architecture.md's "hidden flag + palette index", and that bit was a dense
[:vis] wearing a different hat -- two mechanisms for one question, which is how
a part ends up hidden by one and shown by the other.
- The palette is a parameter of evaluation, not a global. A node names a TONE;
which ramp that tone is read in belongs to the timeline it sits in.
- :over layers and a symbol :rate THROW rather than being ignored. Neither is
built and nothing can produce one, so this can only fire on data that has run
ahead of the code. A silently dropped override is a hand correction the user
made once, watched fail, and has no reason to trust again.
Three findings the model produced rather than received:
- Presence propagates asymmetrically. An absent transform drops the subtree; an
absent [:geom :pts] drops only that node, because an absent mouth outline has
nothing to draw but the head it hangs off has not moved. That asymmetry is the
reason presence is tracked per channel and not per node.
- Z paths need lexicographic compare, not `compare`, which orders vectors by
count first -- so a cel three levels under "a1" would jump in front of a bare
"a2" and the layer order would mostly work.
- A node stencilled by something that drew nothing is dropped, not drawn
unclipped: an iris floating over the cheek is worse than a missing iris.
docs/ revised alongside, and those revisions are the load-bearing part:
- A scene, a timeline and a symbol are one type. The doc had two structures with
the same fields and never said so. Two axes of nesting are now separated --
parent/child within a timeline is flat with parent pointers, instance nesting
is by reference -- which is why "nestable" and "flat" only sounded
contradictory.
- Palettes are named, live on the project, and are ENABLED on a timeline as a
channel. Absent inherits; present travels with the timeline, so a symbol
authored against :night stays night wherever it is placed. The output index
space is the concatenation of the named ramps, which keeps one buffer and one
flat table and incidentally stops two nodes in different palettes colliding on
a stencil.
- Stabilisation is a channel, not a mode: {s, theta, tx, ty} IS [:xform :*], so
the normalise on/off/per-plate toggle is which of the three channel shapes the
:head node carries. Always measure and always store factored -- smoothing and
velocity-minimum key selection both need the split to exist in storage.
- There is no camera node and none is needed. Placement is a node transform, the
stage clips what hangs off it, and project dimensions are independent of the
footage. `makeXform` is therefore not to be ported: it bakes a cropping
decision into every stored vertex.
- Export is removed. The .take writer was for an Animator Pro render script; the
target is encoding video in the browser, and step 9 now says not to port the
old one.
demo/swarm is 120 shapes on six orbits, entirely dense blocks behind store
handles -- the shape freeze produces at step 5, and the first thing to exercise
that path under load. It plays at 30fps, and bench-test keeps a deliberately
loose floor under it because a performance regression here does not announce
itself: the picture stays correct and merely arrives late.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PDfHGdV39zu6rvgbBTfDaT
2026-09-27 17:28:05 -04:00
## Two evaluators, on purpose
`domain/scene` has both `eval-frame` and `resolver` , and they are not
alternatives:
- **`(eval-frame scene f store)` ** is the specification. Allocating, order-free,
obviously correct. Tests and one-off renders use it.
- **`(resolver scene store)` -> `(fn [f] ops)` ** is what playback uses. It caches
the topological order and the z paths, holds a cursor per channel and reuses
one point buffer per node, so a frame allocates the op maps and nothing else.
Both run the same walk, parameterised by how a channel is read and where its
points are written — two independent implementations of frame evaluation would
drift, and the drift would look like a rendering bug rather than like two
functions disagreeing. What differs between them is exactly the part that can be
wrong, and `scene-test` asserts they agree frame for frame in forward, backward
and random order.
Because the resolver reuses its buffers, **ops must be rasterised before the
next frame is asked for.** That is the contract the rAF loop wants anyway: it
reads, blits, and dispatches nothing.
