markdown-to-pdf · MD-to-PDF Booklet

Turn a Markdown file into a print-ready booklet PDF — multiple small pages imposed on A4 sheets, with cut lines and page numbers, ready to print, cut, and slot into a notebook.

Built for printing devotionals/notes as small booklet pages, but works for any Markdown. Fully self-contained: no browser, no network, no system fonts required — rendering is done in-process and three fonts are bundled.

A Java 21 + JavaFX application. The pipeline is pure JVM:

Stage	Library
Markdown → HTML	flexmark-java
HTML + CSS → A6 PDF	openhtmltopdf
N-up imposition (cut lines, page numbers)	Apache PDFBox
UI	JavaFX

The original Python/PyMuPDF implementation is kept for reference under legacy/ (run python legacy/md2a6_app.py).

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What it produces

Pages are rendered at A6 size, then imposed on A4. Because A6, A5, and A4 all share the same √2 aspect ratio, each layout fits with at most a 90° turn and no distortion:

Pages/sheet	Result	Layout	Notes
4	four A6 pages	2×2	the default
2	two A5 pages	1×2, turned 90°	cut across the middle, rotate each half
1	one A4 page	1×1	full sheet

Every layout includes:

• 12 mm left margin for hole-punching / perforation
• 1 mm safety inset from the sheet edge (printer unprintable border)
• inner cut lines only (no wasteful outer border)
• page numbers bottom-right (they rotate with the page in 2-up mode)
• justified text, bold headings, full Romanian diacritics (ș ț ă î â, „ " quotes)

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Requirements

• JDK 21 (e.g. Temurin 21). Provides java and jpackage.
• Maven — none needed globally; the project ships the Maven Wrapper (./mvnw), which provisions the pinned Maven version automatically.

The output filename's title is taken from the first line of the Markdown file (leading # stripped).

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Build a portable app (no Java install needed by end users)

./mvnw -Pdist package

This produces a self-contained app-image under target/dist/MD-to-PDF Booklet/ — a portable folder bundling a trimmed Java runtime + JavaFX + the fonts (~80 MB, no separate Java install required). Copy it anywhere and run MD-to-PDF Booklet.exe.

The app-image is per-OS — build it on each platform you want to ship.

Use it

1. Source file — choose your .md
2. Typeface — pick one of three
3. Layout — 4, 2, or 1 per sheet (the live preview shows the imposition)
4. Save as — defaults to <title> - A6 <N>up.pdf next to the input
5. Generate

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Run / develop from source

./mvnw package                      # builds the runnable fat jar
java -jar "target/app/md2pdf.jar"   # GUI
java -jar "target/app/md2pdf.jar" sample.md   # CLI

target/app/md2pdf.jar is a shaded jar with everything (incl. JavaFX) bundled, launched through a non-Application Launcher class so JavaFX starts cleanly from the classpath.

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CLI

Passing arguments runs the program in command-line mode; with no arguments it opens the GUI.

md2pdf.jar <file.md> [font-key] [out.pdf] [per-sheet:1|2|4]

Argument	Required	Default
file.md	yes	—
font-key	no	EB Garamond (classic serif)
out.pdf	no	<md-title> - A6 <N>up.pdf next to the input
per-sheet	no	4

Font keys (quote them — they contain spaces):

• EB Garamond (classic serif)
• Lora (modern serif)
• Source Sans (clean sans)

Examples

# defaults: EB Garamond, 4-up, auto-named output
java -jar "target/app/md2pdf.jar" notes.md

# Lora, two A5 pages per sheet, explicit output
java -jar "target/app/md2pdf.jar" notes.md "Lora (modern serif)" booklet.pdf 2

# the packaged app works the same in CLI mode
"target/dist/MD-to-PDF Booklet/MD-to-PDF Booklet.exe" notes.md "Source Sans (clean sans)" out.pdf 1

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Adding more fonts

1. Drop static Name-Regular.ttf and Name-Bold.ttf into src/main/resources/fonts/.
2. Add one line to the FONTS map in src/main/java/com/steadfastknight/md2pdf/FontRegistry.java:

   FONTS.put("My Font (label)", new Font("Name-Regular.ttf", "Name-Bold.ttf", 7.8));

   The size is the body point size (headings scale from it). Tune per font.

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Layout / tuning reference

Constants live in src/main/java/com/steadfastknight/md2pdf/Layout.java (and font sizes in FontRegistry.java):

Constant	Meaning	Default
A6_W, A6_H	rendered page size	105 × 148.5 mm
ML, MT, MR, MB	page margins (left wide for hole-punch)	12/10/5.5/10 mm
EDGE	safety inset from A4 sheet edge	1 mm
GUTTER	gap between cells	0 mm
LAYOUTS	pages-per-sheet → (cols, rows, rotation)	1/2/4
Font.size	per-font body point size	7.5–8.4 pt

The page CSS (justification, heading scale, A6 @page box) is built in Css.java.

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Fonts & licensing

Bundled fonts are under the SIL Open Font License (free to use and redistribute):

• EB Garamond — Georg Duffner, Octavio Pardo
• Lora — Cyreal
• Source Sans 3 — Adobe

All cover the Romanian Latin Extended characters (ș ț ă î â, „ " quotes).