Three problems from the first cut (user report 2026-09-13), all rooted
and fixed:
1. Boundaries reshaping on zoom — an inward offset normal. In y-down
screen coordinates, monotone chain yields clockwise-on-screen hulls,
whose OUTWARD normal is (dy, -dx); the code used (-dy, dx), so the
14px padding pulled every hull vertex 14-20px INWARD. Zoomed in this
mostly passed; zoomed out, once a cluster projected smaller than ~2x
the pad, vertices crossed the centroid and the polygon self-
intersected — spiky garbage re-forming every frame. Geometry moved to
components/cluster-geometry.ts (exported, unit-tested) with the
corrected normal; tests pin the direction (offset moves every vertex
AWAY from the centroid; stays sane when the hull is smaller than the
pad; hull orientation asserted clockwise-on-screen).
2. GPU ~100% + audible coil whine on any interaction — the hull redraw
was hooked to sigma's afterRender, which fires for EVERY render
including ~a dozen hover-animation frames per hover, and each redraw
rasterized ~32 fills through ctx.filter blur(12px), a GPU-heavy
full-canvas filter. Now: redraws happen ONLY on camera updates and
resizes (hover leaves the hull canvas untouched — verified live),
and the blur is replaced with layered low-alpha fills (soft edge at
a fraction of the cost, no canvas filter at all).
3. Cluster labels cluttering the view — a persisted 'Cluster labels'
checkbox in the rendering settings (hulls stay, text toggles).
377/377 tests, typecheck, lint, build green. Live-verified: hover does
not repaint hulls, zoom does; far zoom-out yields 3 contiguous tinted
regions (no fragmentation); toggle clears/returns labels and persists.
Core-survival labelings (vision section 1, DECIDED 2026-09-13):
ClusterLabeling records in a new append-only ledger
(data/graph/cluster-labels.jsonl), immutable, id = clu_ + sha256 of the
sorted core so re-naming races and re-runs dedupe at the store seam.
matchClusterLabelings (core/clusters.ts, pure): a community keeps a
record's label while at least half its core survives in it; both sides
single-successor (a split keeps one name; greedy by overlap, ties to
the newer record).
The namer (src/agent/subagents/cluster-namer.ts): ONE singular cheap LLM
call (new 'labeler' role, glm-flash/low) names every new/changed
community at once, given member names + statements (capped at 12
members per cluster). refreshClusterLabels runs POST-EXTRACTION
(user-decided) from both front doors, fire-and-forget — naming failure
never fails the run; refreshes serialize behind a chain so parallel
imports never mint duplicate labels. import-notes.ts awaits
clusterNamingSettled before exit.
Payload: GraphSnapshot.clusters (>= MIN_CLUSTER_SIZE 3) joins detection
with labelings at read time — claimed clusters carry the record's label
and id; unlabeled ones carry a member-hash id and null label. Detection
is deterministic so no memo in v1 (ms at current scale; revisit at
vault scale).
Tests (372/372): matcher half-rule/split/merge/greedy/tie cases; naming
end-to-end through importNotes (one call, one record, claim on
re-refresh), naming failure non-fatal; snapshot derivation with
labeling join; 11 test pipelines now pin an explicit labeler seam.
detectCommunities(nodes, edges) in src/core/clusters.ts (new dep
graphology-communities-louvain): Louvain modularity over the undirected,
unweighted follows+supports structure (user-decided 2026-09-13). The
random-walk traversal runs on an inlined seeded mulberry32 so the same
graph always yields the same partition; community indices are still
unstable across edits, which is exactly why labelings (phase B) key to
sorted MEMBER SETS. follows+supports between the same pair collapse to
one edge; self-loops and dangling edges are skipped defensively; no
min-size filter here (the >=3 render threshold is a presentation rule).
Tests: two-cliques-plus-bridge split, determinism, singleton/empty
graphs, pair collapse, defensive skips, member sorting. 363/363.
Real-data smoke over the current notes graph: 338 nodes / 211 edges ->
138 communities, modularity 0.95, and the big ones are exactly the
learn-session topics (databases, differential forms, sales, servers,
vim, copulas...). 32 communities clear the >=3 render threshold.
amosblomqvist