One self-contained demo buffer for every feature, driven by single
keys, with per-reflow milliseconds in the header line:
-/+ width ±20 px (arrows: ±4) d animated width sweep + fps report
a cycle 4 alignments p hanging punctuation
i first-line indent (2 em) s wedge parshape (Elisp 2D path)
c C engine vs pure Elisp w follow window width (auto-mode)
The sample text bundles a verbatim-protected code block, an inline
no-break atom, and NBSP-joined figures; the engine indicator honestly
shows when a feature (indent/parshape) bypasses C. Launch:
emacs -Q -L /path/to/emacs-kp -l tests/ekp-showcase.el -f ekp-showcase
Verified interactively in GUI Emacs (justify 480→360 px, protrusion +
indent on: state and timing update live).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>