include "print.m";
print := load Print Print->PATH;

Print: module
{
	PATH: con "/dis/lib/print/print.dis";
	CONFIG_PATH: con "/lib/print/";

	init: fn(): int;
	set_printfd: fn(fd: ref Sys->FD);
	print_image: fn(p: ref Printer, display: ref Draw->Display, im: ref Draw->Image, pcwidth: int): int;
	print_textfd: fn(p: ref Printer, fd: ref Sys->FD, ps: real, pr: int, wrap: int): int;
	get_defprinter: fn(): ref Printer;
	set_defprinter: fn(p: ref Printer);
	get_size: fn(p: ref Printer): (int, real, real);	# dpi, xinches, yinches
	get_printers: fn(): list of ref Printer;
	get_papers: fn(): list of ref Paper;
	save_settings: fn(): int;

# Printer types

Ptype: adt {
	name: string;
	modes: list of ref Pmode;
	driver: string;
	hpmapfile: string;
};

# Paper sizes

Paper: adt {
	name: string;
	hpcode: string;
	width_inches: real;
	height_inches: real;
};



# Print modes

Pmode: adt {
	name: string;
	desc: string;
	resx: int;
	resy: int;
	blackdepth: int;
	coldepth: int;
	blackresmult: int;
};

# Print options

Popt: adt {
	name: string;
	mode: ref Pmode;
	paper: ref Paper;
	orientation: int;
	duplex: int;
};

# Printer instance

PORTRAIT: con 0;
LANDSCAPE: con 1;

DUPLEX_OFF: con 0;
DUPLEX_LONG: con 1;
DUPLEX_SHORT: con 2;

Printer: adt {
	name: string;
	ptype: ref Ptype;
	device: string;
	popt: ref Popt;
	pdriver: Pdriver;
};

};


Pdriver: module
{
	PATHPREFIX: con "/dis/lib/print/";
	DATAPREFIX: con "/lib/print/";

	init: fn(debug: int);
	sendimage: fn(p: ref Print->Printer, tfd: ref Sys->FD, display: ref Draw->Display, im: ref Draw->Image, width: int, lmargin: int): int;
	sendtextfd: fn(p: ref Print->Printer, pfd, tfd: ref Sys->FD, ps: real, pr: int, wrap: int): int;
	printable_pixels: fn(p: ref Print->Printer): (int, int);

};

The Print module

init()

Init must be called once to initialise the internal state of Print.

set_printfd(fd)

set_printfd provides a file descriptor to be used for output. By default, output is sent to the file or device specified in the Printer adt.

print_image(p,display,im,pcwidth)

print_image prints a page containing a single image. The image is centred horizontally, and is scaled up to fill the percentage of the available width specified by pcwidth.

print_textfd(p,fd,ps,pr,wrap)

print_textfd prints one or more pages of text on printer p from the file open for reading on fd. The point size is controlled by p. If the printer does not support the specified point size an alternative size will be used. A point size of 0.0 can be used to select the printer's default size (usually 12 point). If pr is non-zero, a proportionally-spaced font will be used (if available). If wrap is non-zero, lines will be wrapped if they overflow the page width (if this feature is supported by the printer).

get_defprinter()

get_defprinter returns the default printer (in /lib/print/defprinter).

set_defprinter(p)

set_defprinter sets the default printer (in /lib/print/defprinter).

get_size(p)

get_size returns the resolution in dots per inch and the total number of pixels available for printing in the x and y direction. Before calling this function the orientation should be set if required.

get_printers()

get_printers returns a list of all available printers (in /lib/print/printer.cfg).

get_papers()

get_papers returns a list of all available paper sizes (in /lib/print/paper.cfg).

Data Structures

Ptype

- specifies a Printer Type, with fields:

name:

Name used to refer to this printer type

desc

Description

modes

List of supported print modes

driver:

The .dis file specification of the printer driver

hpmapfile:

For HP printers, the name of the color map file

Paper

- specifies the dimensions of a type of paper

name:

Name used to refer to this paper size

hpcode:

For HP printers, PCL code used for this paper size

width_inches:

Width of paper in inches

height_inches:

Height of paper in inches

Pmode

- specifies a print mode

name:

Name used to refer to this print mode

desc:

Description

resx:

X resolution in dots per inch

resx:

Y resolution in dots per inch

blackdepth:

Depth of black component in bytes

coldepth:

Depth of color components in bytes

blackresmult:

Resolution multiplier of black component (1 means same as base x resolution)

Popt

- specifies a set of Print Options

name:

Name of a Printer to which these print options apply

mode:

The name of a print mode

paper:

The name of a paper size

orientation:

Paper orientation - either PORTRAIT or LANDSCAPE

duplex (NB DUPLEX IS NOT CURRENTLY SUPPORTED):

Duplex setting - DUPLEX_OFF or DUPLEX_SHORT or DUPLEX_LONG

Printer

- specifies a printer instance

name:

Name used to refer to this printer

ptype:

The printer type

device:

The name of the file to be used for output (eg /dev/lpt1data)

popt:

The print options

driver:

The printer driver module handle

Configuration Files

There are configuration files to initialize the Printer Types, Print Modes, Paper Sizes Printers and Print Modes. They all have a similar format, with fields corresponding to the relevant adt. Here is an extract from the paper.cfg file:

A4=
	hpcode=26
	width_inches=8.3
	height_inches=11.7
A5=
	hpcode=25
	width_inches=4.15
	height_inches=5.85

Aliases can also be defined, such as

myA4=A4

The final configuration file, defprinter, just contains the name of the default printer.

/lib/print/*.map

HP color maps.

/lib/print/ptype.cfg

Print Type configuration file.

/lib/print/pmode.cfg

Print Mode configuration file.

/lib/print/paper.cfg

Paper Size configuration file.

/lib/print/printer.cfg

Printer Instance configuration file.

/lib/print/popts.cfg

Print options configuration file.

/lib/print/defprinter

Holds the name of the default printer. Not needed if there is only one printer available.

/appl/lib/print/print.b

Implementation of the Print module.

/appl/lib/print/*_driver.b

Printer-specific driver modules

/appl/lib/print/scaler.b

Scaler module