Four more Tailwind classes, all four verified against draw.io's own source in
public/drawio rather than against a prose reference — which is how three earlier
exclusions turned out to be wrong:
rounded-* mxShape.js:1172-1189 — absoluteArcSize=1 switches arcSize to
absolute pixels and halves it, so the same class is the same
corner on every box. Previously excluded as 'percentage only'
shadow-sm..xl mxShape.js:505-535 — getShadowStyle reads five independent
params, not one flag, so Tailwind's offset+blur rungs map one
to one. Previously excluded as 'six sizes collapse to one'
line-through mxConstants.js:2054 FONT_STRIKETHROUGH: 8, read at both
mxText.js:723 and :1040. The bitmask has four bits, not three
border-none the only one of the four that adds something previously
inexpressible: a fill with no outline
Also fixes an edge style growing 76 characters per re-layout, without bound. The
router recomputes ports on every pass, and appending them to a style recovered
from the canvas — which already carried the previous pass's eight port keys —
grew the string forever. draw.io resolves duplicates last-wins so the arrow
always looked right; a byte-identity check is what caught it.
Two traps found while wiring the readback, both the same shape: a value the
THEME emits being recorded as one the model asked for. strokeColor=none from a
filled or ghost role, and rounded=0 from the fallback style. Either one would
outlive a set_role, since that clears style but keeps text.
Deliberately not included, with reasons in tw.ts: per-side borders and per-corner
radius (both would take the shape slot, and what a node IS matters more than
which of its edges show), per-side padding (draw.io's keys pad the label, not the
room left for children), text-shadow (a bare flag with no offset or blur),
opacity (Tailwind's is any integer, not a scale), tracking/uppercase/leading
(absent from draw.io — zero grep hits, not merely coarse).
615 tests, 90 new. Browser-verified: four shadow rungs visibly differ, radius is
real pixels, terminator + rounded-lg becomes a small-cornered rounded rect while
an untouched terminator stays a stadium.
The layout vocabulary's biggest gap, after D2/TALA's 'containers are
first-class at every layout stage': hierarchical zones and arrow-ordered
graphs could not mix. draw_graph did whole-page flowcharts, containers did
nesting, and 'an architecture zone whose contents follow the data flow' was
inexpressible.
add_graph is a macro operation: nodes+edges go through the existing layered
pass (graph.ts — cycle breaking, longest-path layering, barycentre crossing
reduction) which emits ordinary container/box/link operations, and the
resulting block participates in the outer flexbox like any node. dir col/row
transposes the flow. No new layout code — the coordinate work was always
generic; what was missing was the entry point below page level.
Synthetic layer ids are namespaced by the graph's own id (g1__layer0), fixing
the collision that previously made a second graph per page impossible.
graph.ts gains parent/prefix/rootId options; draw_graph keeps its behaviour
as the page-level case of the same code path.
4 new tests: embedding in a flexbox column, two graphs per page, dir
transposition, unknown-endpoint errors. 565 unit tests green, 8 engine e2e
green. Acceptance: three-zone architecture diagram (person/cloud zone,
arrow-ordered pipeline zone with decision branches and a bold arrow,
cylinder/queue storage zone, cross-zone links) verified in the real editor.
