TurboPDF — TurboPrint-compatible PDF printer driver for MorphOS/AmigaOS

TurboPrint driver (TurboPDF.tpd) that intercepts PRD_DUMPRPORT / PRD_TPEXTDUMPRPORT I/O requests and outputs a PDF to stdout using libHaru (hpdf.library on MorphOS).

Any Amiga application can select it in the printer preferences and capture stdout to obtain the generated PDF.

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Files

File	Description
tpd.c	PrinterSegment driver — pure C, no assembly
turboprint.h	TurboPrint pixel format constants + TPExtIODRP struct
Makefile	Build system for ppc-morphos-gcc
external/libharu	libHaru git submodule, built statically into the driver

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How it works

The driver is a PrinterSegment — a LoadSeg'd code module loaded by printer.device. It is not an Exec device; it has no romtag, no RTF_AUTOINIT, and no OpenLibrary/CloseLibrary reference.

The first bytes of the loaded module are a struct PrinterSegment containing a PrinterExtendedData (PED) which exposes entry points:

Init, Expunge, Open, Close, DoSpecial, Render

Three data paths:

Text path (text mode → ped_ConvFunc) printer.device delivers printable characters to the driver's ped_ConvFunc (requires driver version ≥ 34). Lines accumulate and are emitted as PDF pages via libHaru. Page geometry is taken from the driver's copy of the user's Preferences (pd_Preferences): the selected paper size (US Letter, A4/A5/A3..A0, Legal, tractor feed) maps to PDF page dimensions in points, the left/right margins (in characters × pitch) define the printable area, and the spacing selection sets the line pitch (6 or 8 lines/inch). Unknown sizes fall back to US Letter. \n/\r start a new line, tab expansion is to 8-column stops, and \014 (formfeed) ejects a page. ANSI SGR sequences are recognized through the Commands table entries that contain \377, which route to DoSpecial in its text form: aSGR0 resets, aSGR1/aSGR22 toggle bold, aSGR3/aSGR23 toggle italic, aSGR4/aSGR24 toggle underline (per-character styles). Colored runs arrive through the 8-bit CSI form (see below): 30-37 / 40-47 and 90-97 / 100-107 select the ANSI foreground/background palette, 38;5;n / 48;5;n select an xterm-256 colour, and 38;2;r;g;b / 48;2;r;g;b set 24-bit RGB; 39/49 restore the default. Colors are shared with the styles: runs split on every attribute, a coloured background is painted as a filled rectangle behind the run, and underlined runs are stroked in the current foreground color. The base-14 Helvetica family is used: Helvetica, Helvetica-Bold, Helvetica-Oblique, Helvetica-BoldOblique; underlined runs get a stroked rule. The point size follows the selected pitch — PICA 10pt, ELITE 8.5pt, FINE 7pt — override the default with -DTP_FONTSIZE=<pt> in the build. Characters ≥ 0x80 are mapped through the driver's 8-bit character table (ped_8BitChars, one set): C1 controls 0x80..0x9F become spaces and the Latin-1 range 0xA0..0xFF keeps its glyph, so accented text prints correctly.

Hyperlinks — text URLs become clickable PDF links:

• Auto-detection: http://, https://, ftp:// and www. tokens in the printed text get a URI link annotation matching the rendered glyphs (trailing sentence punctuation trimmed).

• OSC 8 (terminal hyperlinks): an explicit link is opened and closed in the character stream with ESC ] 8 ; <id> ; <uri> BEL (or ESC ] 8 ; ; <uri> ESC \ ) and closed with an empty URI. The region gets a URI link annotation with the given URI. An open link also survives a formfeed so multi-line hyperlinks keep working. ESC] is not a standard printer escape, so printer.device passes the sequence through unmodified for the driver's ped_ConvFunc to consume (it never appears on the printed page).

• 8-bit ECMA-48 forms are recognised as well: CSI 0x9B and OSC 0x9D, terminated by ST 0x9C (BEL for OSC). ped_ConvFunc parses 0x9B <params> m with the same SGR mapping as the table commands (0,1,3,4,22,23,24 -> aSGR0..aSGR24) plus the full color subset above, and routes 0x9D through the same OSC-8 parser as the 7-bit ESC] form. Both 8-bit controls are dropped before they can reach the text.

  Alignment is set with the ECMA-48 justification sequence ESC [ <ps> SP F (0x9B <ps> 0x20 F in 8-bit form). It applies to the whole line that follows: 6 flushes left (default), 7 centres, 8 flushes right, 2 justifies (word fill, distributing the leftover space across the gaps between words), and 1 ends justification and returns to flush left. A line wider than the printable area stays flush left. Alignment interacts with styles, colors and both link schemes (rects shift with the line).

  PDF passthrough (aESTEND / extended command) — arbitrary PDF operators can be embedded verbatim in the output. Send the extended-command escape ESC [ <n> " x (aEXTEND, ANSI command 75) followed by <n> bytes of raw PDF content; the driver writes them straight into a dedicated page's content stream. <n> bytes are consumed, then text mode resumes (the count makes the block self-terminating). Consecutive extended commands keep appending to the same page, so each chunk must be balanced (BT/ET or q/Q, etc.). This mirrors the standard "extended commands" feature of the Amiga PostScript driver. Requires the bundled libharu extension HPDF_Page_AppendRaw (present in the static build; the weak reference degrades to a no-op against the system hpdf.library).

TurboPrint path (PRD_TPEXTDUMPRPORT → DoSpecial) The driver reads the raster bitmap passed in the TPExtIODRP request and embeds it as a raw RGB image via HPDF_LoadRawImageFromMem.

Standard path (PRD_DUMPRPORT → Render) The driver converts the RastPort bitmap to RGB24, accumulates it across bands and embeds each band as a raw RGB image via libHaru.

Output PDF is written to stdout (via dos.library Output()/Write()) when the printer is closed. The caller captures stdout to obtain the generated PDF.

Supported driver entry points

Entry	Description
Init	Save PrinterData pointer; reset PDF + text state
Open	Create new HPDF document
Close	Flush final text page + PDF to stdout; free HPDF document
Expunge	Emergency cleanup if Close wasn't called
ConvFunc	Text-mode: accumulate characters and emit PDF text pages
DoSpecial	\377 text-command form: toggle bold/italic/underline styles. IORP form: handle PRD_TPEXTDUMPRPORT (TurboPrint bitmap data). Dispatch is by first word ≤ aRAW (text) vs. a pointer (IORP)
Render	Handle PRD_DUMPRPORT (standard RastPort raster data)

Struct packing The PrinterSegment and PrinterExtendedData structs are defined locally with __attribute__((packed)) to match the exact m68k byte layout expected by printer.device, regardless of PPC (MorphOS) alignment rules. The TPExtIODRP struct is also packed.

Build

make            # release build → build-release/TurboPDF.tpd
                #   libHaru built statically from the bundled submodule
make static=0   # dynamic build — link against the system hpdf.library
make debug=1    # debug build   → build-debug/TurboPDF.tpd
make check      # clean-builds static + dynamic, verifies output
                #   make check CHECK_MODES=static   (build one mode only)
make clean

(requires ppc-morphos-gcc. The static build pulls libHaru from the external/libharu submodule, so no system hpdf.library is needed there; the dynamic build requires the MorphOS SDK with hpdf.library. All image and PDF output goes through libHaru — no jpeg/jfif dependency.)

Pull submodule before building:

git submodule update --init

Status Untested on real MorphOS hardware. May need adjustments for hpdf.library API compatibility, linker script conventions, and bitmap conversion in the Render path.

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References

TurboPrint

• TurboPrint SDK (tp_devel.lha, 9k): https://www.irseesoft.de/tp_what.htm
• Canonical turboprint.h (AROS-vpdf): https://github.com/wattoc/AROS-vpdf/blob/master/turboprint.h
• VPDF TurboPrint printer path (poppler_printer.cpp): https://github.com/wattoc/AROS-vpdf/blob/master/poppler/poppler_printer.cpp
• TurboPrint on Wikipedia: https://en.wikipedia.org/wiki/TurboPrint

libHaru

• Homepage / source: https://github.com/libharu/libharu
• API reference: https://libharu.sourceforge.net/api.html

Amiga/MorphOS printing

• Amiga Printer Device docs (RKRM): https://wiki.amigaos.net/wiki/Printer_Device
• MorphOS Printing overview (PDF): https://www.morphos-storage.net/?id=1588365
• MorphOS Library — Printing: https://library.morph.zone/Printing
• RKRM_Devs source archive (Aminet): http://aminet.net/package/dev/src/RKRM_Devs_prgs

PrinterSegment docs

• https://wiki.amigaos.net/wiki/Printer_Device#Creating_a_Printer_Driver

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TODO

• Test on real MorphOS hardware.
• Implement planar → RGB conversion in Render() for classic Amiga bitmaps.
• Investigate per-PrinterData state for concurrent printer instances.
• Top/bottom page margins: Preferences exposes no vertical-margin field (top-of-form is fixed by the device), so a constant margin is used.
• pf_PrintColor is not consulted — the color class is PPCF_COLOR and SGR colors are always honoured.