ekp-protrusion enables microtype-style character protrusion at the
right edge: a line ending in fullwidth punctuation (。、」…) hangs
the whitespace half of the glyph past the flush edge — visually
identical to CLREQ line-end punctuation compression — and latin
periods/commas/quotes and soft hyphens protrude by their configured
ratios (ekp-protrusion-ratios).
Mechanics: per-box tail protrusion, folded through trailing space
boxes into a per-gap array; each DP candidate widens its effective
target (lw = width + release), mirrored exactly in the renderer's
per-line effective width and in the C-result reconstruction, so DP,
rendering and both engines stay coherent. Left-edge protrusion is
documented as out of scope (Emacs cannot render before the line
origin). ekp-region reserves the protrusion width in auto layouts
(ekp-region-protrusion-reserve).
Off by default; all-zero arrays make it a no-op on the shared path.
C module 1.4: break-with-arrays 12→14 args (tail-protrudes array,
hyphen-protrude scalar), batch vectors 14 elements.
Tests: 59 ERT green (deterministic hang check, flush-when-off,
protrusion C parity); fuzz 300/300.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
- text property ekp-no-break turns any span into a rigid typesetting
atom: no line break inside, no hyphenation, literal spacing (space
runs inside the span become preserved space boxes instead of
stretchable glue) — inline code, product names, numbers with units
- character-driven joins: NBSP, NARROW NBSP, FIGURE SPACE keep their
neighbors together (they are boxes whose adjacent gaps are
unbreakable and glue-free — the character supplies its spacing);
WORD JOINER / ZWNBSP attach invisibly like combining marks
- new commands: ekp-no-break-region / ekp-allow-break-region
- overlong atoms fall back to single emergency lines (atomic-run
handling from the break-permission layer); zero C changes needed
Tests: 52 ERT green incl. atomicity across widths, hyphenation
suppression, NBSP/WJ adjacency sweeps; fuzz 300/300 with C parity.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
The renderer (shared by both engines) is now lossless: synthesized
glue carries the original text it replaced (ekp-glue), soft line
breaks carry the whitespace swallowed around the break
(ekp-soft-break), break hyphens are marked (ekp-soft-hyphen), and
paragraph-edge whitespace survives as zero-display ekp-hidden text.
Orphaned ekp--combine-glues-and-boxes / ekp--interleave removed.
New ekp-region.el:
- ekp-justify-region / ekp-unjustify-region: in-place justification
with exact structural restore (character- and property-exact),
robust to edits made while justified
- ekp-auto-justify-mode: keeps the buffer justified at the window
width; debounced re-flow on window resize, incremental
per-paragraph re-justification after edits (served by the
paragraph cache)
- fix found in live GUI testing: buffer-local members of
window-size-change-functions receive the WINDOW as argument and
may run with an unrelated buffer current; the handler now resolves
window and buffer explicitly (regression test included)
Tests: 47 ERT (36 core + 11 region) passing; 300-case fuzz 0
failures (C/elisp parity unchanged); byte-compile clean with
error-on-warn. Verified interactively in GUI Emacs: justified at
1403px maximized, auto-reflowed to 614px on frame resize.
docs: interactive-use section in readme.md / readme_zh.md
ci: byte-compile list includes ekp-region.el
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>