geo_push.hpp and replay.hpp cited memllib @ 0a541cc. upstream/main pins
e291192, where the same code had been deliberately redesigned — and because
InterfaceRL was not in the tree (fixed one commit ago), we carried the
superseded version for months. Three changes, all upstream's:
kGeometricPushScale 0.5 -> 1.0 (InterfaceRL.hpp:409)
kNegLRBase 0.5 -> 1.5 (InterfaceRL.hpp:410)
/(1+len) taper deleted (InterfaceRL.tpp:724)
Upstream's own comment on the taper: "a 'no' should clearly move the mapping
away even from a sound already far from the liked region (the taper used to
kill exactly that case)". The direction is already a unit vector, so the
taper only ever shrank the push for exactly the sounds a user is most likely
to be rejecting.
Cold start is folded into the same path. Upstream's useRandom is
`!havePositives || len <= 1e-4`: with nothing liked yet there is no centroid
to push away from, so every dim goes in a random direction. Ours instead
kept the older 0a541cc fallback — train AWAY from the heard action at a
NEGATIVE lr — which was inert whenever the heard action equalled the net's
own output, i.e. in the common case. One path now, and a "no" moves the
mapping before any likes exist (ml_bench E1: 0 -> 2.3e-3). The
GeometricColdStart action is still reported so callers keep their "like a
few sounds first" prompt; only the training changed.
Measured (ml_bench, one dislike at a point):
A4 0.0157 -> 0.0533 at-point displacement (3.4x), so end to end across
this and the RMSProp fix: 5.3e-5 -> 5.3e-2, ~1000x. The gap to the
legacy Diffuse design closes from ~4100x to ~4.2x.
D1 effective_lr 4.7e-4 -> 1.5e-3; 10 presses now reach 0.34, 100 reach
the full intended push.
A5 compounding 0.87 -> 0.96 (a second press at the same spot is no
longer noticeably weaker than the first).
A7 damage_ratio essentially unchanged (0.87-1.57) — the collateral
damage to protected positives scales with the push and is NOT
addressed here; it is the negative-feedback design question.
NOT adopted, deliberately: upstream's per-tick batch retraining over all
live negatives, and its fixed kDislikeLifetimeMs=2500 in place of our
proportional decay. Both need something the core does not have — a per-tick
call site and a millisecond clock inside nisps/ml — so they change
FeedbackControllerCore's interface rather than its constants. Recorded in
ALIGNMENT's deferred-debt entry alongside the existing one-press-one-step
divergence, and filed as its own task.
test_mlp_geo_dislike.cpp: the taper test now pins its ABSENCE (equal
displacement near and far), the cold-start test pins movement where it used
to pin inertness, and a new test covers the random-direction branch.
ALIGNMENT defect 6b resolved. Gates: build-cpp-tests 139 tests / ctest 4/4,
parity-check PASS (WASM rebuilt), lint-cpp clean, firmware slpworkshop
SUCCESS.
Phase 1 group 2 (L27, L26, L28, S21, L13, ST6, S20).
- L27: fixed_buffer.hpp + its test + the CMake entry — no consumers.
- L26: dislike_multiplier_ and its doubling/halving bookkeeping — upstream
InterfaceRL residue that drove nothing. The audit pointed at the wrong test
file for the surviving reference; the actual assert was in
test_mlp_geo_dislike.cpp:211, removed here.
- L28: added copy_weights_to(std::span<float>) to FixedStorage and
DynamicStorage and switched feedback.hpp's take_snapshot/push_undo/nudge to
it. Drops the permanent whole-net flat_ scratch buffer from FixedStorage and
the per-gesture double copy. Behaviour-identical: same source values, same
write order, same RNG draw order in nudge().
- S21 + L13: deleted NISPS_AUDIO_MEM / NISPS_APP_SRAM / NISPS_AUDIO_FUNC —
zero use sites outside perf.hpp and comments — and rewrote midi_io.hpp's one
misshapen NISPS_AUDIO_FUNC use as a plain `inline void`. perf.hpp now
documents only the inlining/hotness macros that actually exist, and
audio_driver.hpp no longer claims an SRAM discipline the code never had.
- ST6: feedback.hpp's header now describes the four current modes and the
Geometric default, dropping the retracted "geometric push NOT ported" claim.
S20 — OPERATOR DECISION (§7.1): the four legacy feedback behaviours
(RandomiseOutputs, RandomiseMlp, AvoidStyle::Diffuse, the RandomiseMlp branch of
on_drag) are KEPT, not deleted. They are wanted as building blocks for
experimenting with how different instruments feel under different behaviours.
Each is now marked at its definition as deliberately-retained research reserve
so future audits stop flagging it as dead code.
L25 (the 16 KB firmware loss-history buffer) is NOT done here — see the phase
report; it turned out to be coupled into the shared mlp.hpp, and its fate
belongs with the browser telemetry build (§7.3 / plan §6.5e).
Gates: run-all-tests.sh ALL GREEN.
Operator-approved ABI change (P2 stop-point). The WASM MLP is now
MLPCore<DynamicStorage>:
- nisps_ml_create(input, output, hidden[3], n, seed) honours its args;
non-positive/null fall back to the historical 32→[10,14,18]→126, so
every pre-P2 caller (manifold, worker, parity harness) stays
bit-identical. Invalid/oversized dims (>4096) → null.
- NEW nisps_ml_reshape(ml, in, out, hidden, n, spread): fresh net at the
new dims, warm-started via nisps/ml/warm_start.hpp (overlapping region
copied; rest keeps spread init); feedback controller re-created (state
resets — reset-on-reshape modal is the front-end contract). Failure
leaves the old net untouched.
- nisps_ml_describe(ml, out): takes the handle; null reports defaults.
- FeedbackController got the same storage split: algorithms in
FeedbackControllerCore<FbStorage>; FixedFeedbackStorage keeps firmware/
tests source-identical via the old alias; DynamicFeedbackStorage (one
arena) sizes to the runtime net. Firmware .text unchanged (122692).
- MLHandle: per-instance scratch vectors; dropped the dead 2MB
batch_out_scratch.
- TS: types.ts decls (+_nisps_ml_reshape), wasm-iml re-describes the
created instance, worker carries a shape-contract note for P2.3.
Verified: ctest 4/4 incl. new warm-start grow/shrink test; reshape ABI
smoke (dims honoured, overlap survives, invalid rejected, outputs
bounded); parity PASS unchanged (2.4e-7); lint clean; manifold 9 unit +
20 e2e green; firmware .text 122692 (+0.30% vs pre-P2 baseline).
Add a "grab → move → drop" gesture that moves an existing positive
example's output to a new input position, preserving the output. This is
the new core's home for upstream InterfaceRL's drag-store/reposition-commit,
distinct from Explore→Place (which places newly-auditioned scratchpad sounds).
- nisps/ml/feedback.hpp: begin_reposition()/commit_reposition()/repositioning().
Reuses the Placing state (static_output holds the carried vector) but a
reposition_ flag makes commit AND the mode-switch teardown SKIP the weight
restore — the real net is never set aside here, so restoring snapshot_ would
clobber the live trained net. Guards cancel_place + abort_explore_place.
- firmware glue: state-gate Toggle B. Exploring → reroll/nudge (unchanged);
Idle → MomB1 grab, MomB2 drop (commit + add_example + train). The 4D variant
has no joystick button, so the gesture lives on the momentary toggle. Also
fix a stale top-of-file control-map comment that contradicted the bindings.
- tests: 4 reposition cases (hold without snapshot; commit stores carried
output with no restore; mode-switch aborts without clobber; begin-only-Idle).
- MAP.md: document the full ExploreAndPlace lifecycle + reposition wiring.
Audio-hold (carrying the sound audibly during the move) remains the existing
unwired static_output() TODO and affects Explore→Place identically.
Firmware compile unverified (no arduino-cli); host tests + lint pass.
