Rings that zoom apart, as a flag, so either answer to row 130 is one line at
the call site. DEFAULT IS 'fit' — this changes nothing today.
'fit' keeps every pin at least minSep apart at the chart's own scale and reports
what will not fit. That is the right behaviour for a PRINTED sheet, where there
is no zoom and a dot a reader cannot resolve is a dot that is not there.
'fill-all' places all of them. Separation is in map units, so it grows with zoom:
measured on the shipped table, the worst ring is ring 1 (1,190 groups in the
smallest circle) separating to 8px on screen at z=4.45, and ring 8 (1,932) at
z=3.50. The GROUP label tier already starts at 5.2, so every pin is clickable
before the names appear. At the start zoom the band reads as a dense arc of
colour rather than countable dots, which is the intended appearance — and the
reason a caller in this mode must caption the true total rather than a count
that changes with zoom.
The row count had to follow the POPULATION here, not the pin size. Keeping the
'fit' row count would have packed 1,932 pins into the two rows a band allows at
full size, and they would have sat almost on top of each other along the arc —
the single-line defect again, one level down. Ring 8 uses 14 rows in fill-all
against 2 in fit.
Real table: fit places 1,851 of 7,296, fill-all places 7,296 of 7,296, both with
zero pins outside their band. Six new assertions, and the row-growth arm is
poison-tested: making fill-all reuse the fit row count fails it at "2 rows vs 2".
Found by running the SHIPPED table through the layout instead of the uniform
sample the module was built against. The real near-neighbours data is heavily
skewed — ring 8 carries 1,932 groups, ring 5 carries 100 — and against it
bandFill placed 962 of 7,296. It dropped 87% of the map, and every drop was
faithfully reported, which is exactly why no assertion caught it: all 16 asked
"is the overflow reported?" and none asked "is the CAPACITY right?".
The capacity model counted one circle of pins at the band's innermost radius. A
band has depth, so it holds several concentric rows, each with its own
circumference. Counting them is a ~2x correction at ringGap 24 and more at
larger gaps; on the real table it takes placement from 962 to 1,851 on the gate's
geometry and every under-full ring now places everything it is given.
Placement had to follow: a hashed radius with one angular step was fine while a
ring held a dozen pins and wrong once it held hundreds, because two pins could
take nearly the same angle at nearly the same radius while the capacity sum
insisted there was room. Pins are now dealt round-robin into rows, each row
evenly spaced across the usable arc, staggered a quarter slot so adjacent rows
do not line up radially and read as spokes.
Two bugs found on the way, both by the gate failing honestly:
- the stagger first added half a step to every odd row, which pushed that row's
last pin past the end of the arc and into the label's keep-out — 7 overlapping.
Staggering WITHIN the slot keeps every pin inside its own slot.
- the shrink arm tested at 200 groups, which only crowded a ring while capacity
was undercounted. It now tests at 2,000, the honest pressure for a 7,296-row
table, and still reaches the pin floor and reports.
The new capacity arm asserts a RATIO against the single-row count, not a magic
number: its first version hardcoded ">400" from the component's ringGap of 22
while the gate builds radii at 24 — the code was right and my threshold was
guessed. Poison-tested: forcing rows back to 1 gives 1.05x and fails both arms.
layoutCenteredSet gives every group on ring N the same radius, so a crowded ring
draws as one line of dots on a circle. The target needs each ring to be
a BAND, groups spread evenly through it, never overlapping each other or the
ring's label.
library/components/charts/ringBands.js is that geometry, with no Vue, no engine
and no DOM, so the Wall poster can consume the same module rather than growing a
second copy of it. bandFill() places; curvedRingLabels() returns each label's arc
AND the keep-out that bandFill refuses to place inside — computed from one source
so "pins never overlap the labels" is true by construction rather than usually.
Determinism is a requirement, not a nicety: every position is a pure function of
the item's own id, so two printings of one packet compare sheet to sheet and a
dot that moves means the DATA moved. There is deliberately no seed. Input order
does not affect any position either, so a caller that filters or re-sorts does
not reshuffle the chart.
An over-full ring SHRINKS its pins to a floor before anything is dropped — a
visible pin beats an unplaced one — and only then reports the remainder with the
ring and the counts.
check:ring-bands, 16 assertions, every arm with a negative control. One arm is
there because this gate passed the bug it now catches: uncapped, a long label on
ring 1 wanted 96% of that small circle, so capacity was zero and all twelve
groups on the innermost ring were reported unplaced while every arm stayed green
— "reported, not silently dropped" is not the same promise as "the ring draws".
Labels now truncate at a share of their own circumference and report how many
characters fit. Poison-tested: restoring the old share reproduces "empty rings: 1".
