GNU Ghostscript 2.6.1 Amiga port
================================
This port requires:
- An Amiga equipped with an '020 CPU and an '881 FPU or any successor
CPU/FPU model and Kickstart 2.04 or higher.
- Approx. 4.7 MBytes of hard disk space available.
- A minimum of 1 MByte of chip memory, depending on what you will want to
do with the interpreter. Printer output requires at least 2 MBytes of
contiguous memory (any memory, not necessarily chip memory).
- ixemul.library and a bunch of Postscript/Ghostscript fonts.
New Amiga features in this release
----------------------------------
The v2.6.0 port used to implement only monochrome drivers, the v2.6.1 port
supports colour output on most devices, exceptions where noted. You don't
need a special brand of graphics hardware expansion, colour output will
work on any Amiga model, provided there is enough memory available. All
devices capable of doing colour output will reduce the number of colours to
be displayed if in dire need of memory. As for the display oriented devices
this will go mostly unnoticed as the Ghostscript halftoning algorithms will
compensate for any colour reductions. However, printer output quality is
very likely to suffer from colour reduction. So, watch out!
As the display oriented devices start up in colour output mode, black &
white rendering may be slightly slowed. The printer device is configured
according to the Preferences settings; `Black & white' will result in
monochrome output, `Grayscale 1' and `Grayscale 2' will also produce
monochrome output but will internally use a true colour representation of
the page, so does `Color'. Please note that `true colour' refers to the
Amiga 12 bit colour model, at this time of writing 24 bit colour printing
is not yet implemented.
The default output device (a super-bitmap window to opened on the
default public screen, such as Workbench) will take advantage of the
Kickstart 3.0 pen sharing feature if enough colours (eight or more)
available.
The v2.6.0 port used to rely on printer drivers to initialize their maximum
page size information upon startup. Several users reported problems with
certain drivers which would make this information available only after
having been asked to do so. The v2.6.1 port now follows the programmers'
guidelines how to determine the maximum page size closely. The driver may
still complain if configured for `Grayscale 1', `Grayscale 2' or `Color'
output and there is not enough memory available for the page to be
displayed.
Installation
------------
Enter the command line interpreter, Create a directory on your hard disk
drive, label it "ghostscript". Let's assume that the fully qualified name
of this directory will be "Work:ghostscript". Enter this directory and
unpack the archives "gs-2.6.1-amiga.lha" and "gs-2.6.1-fonts.lha". This
will create the directory "Fonts" which holds all Ghostscript fonts, the
directory "doc" which contains the Ghostscript documentation files, the
directory "examples" which is to hold some Postscript example files and the
directory "libs" which contains `ixemul.library'. Now edit your
`S:User-Startup' file, adding the following lines:
Assign ghostscript: "Work:ghostscript"
Path ghostscript: add
Assign Libs: ghostscript:libs add
Save the file back to disk and reboot your machine.
Running the interpreter
-----------------------
Enter the command line interpreter, type "gs" and press return. The
interpreter will be loaded and will try to initialize itself. If
successfully initialized, a window should have been opened on the Workbench
screen. The Shell window now should display the following text:
Initializing... done.
Ghostscript 2.6.1 (5/28/93)
Copyright (C) 1990-1993 Aladdin Enterprises, Menlo Park, CA.
All rights reserved.
Ghostscript comes with NO WARRANTY: see the file COPYING for details.
GS>
At the command prompt, enter "(ghostscript:examples/golfer.ps) run" and
press return. Click on the `Zoom' button in the top right corner of the
window to bring it to full screen size, move the scrollers and watch what
will happen. When rendering is finished, the Shell window will display the
following text:
>>showpage, press <return> to continue<<
Press return to erase the contents of the window and to continue. The
interpreter will be in interactive mode again, enter "quit" and press
return to end this session.
For more information refer to the documentation in the "ghostscript:doc"
drawer.
How to print a document
-----------------------
As the corresponding Ghostscript device will always keep the entire page in
memory the printer need not be capable of strip-printing. The bad news is
that the entire page will consume *a lot* of memory. This Amiga port will
keep the page in any public memory area, so it will not necessarily eat up
precious chip memory. This should make it possible to print pages on Amigas
with only 1 MByte of chip memory or less, provided enough fast memory is
available.
Enter the command line interpreter, type "gs -sDEVICE=amiga_printer" and
press return. This will invoke the Ghostscript interpreter with the
"amiga_printer" device driver selected as the startup device. When the
command prompt appears, enter "(ghostscript:examples/butterfly.ps) run" and
press return. The rendered image will be sent to the printer. When printing
is finished, press return and enter "quit" to end this session.
Note: unless you want Ghostscript to prompt you to press return after each
page is printed and ejected you should include "-dNOPAUSE" on the command
line.
Available device drivers
------------------------
This port implements the following seven device drivers:
amiga
(This is the default output device)
Rendering takes place in a super-bitmap window to be opened on the
Workbench screen. This window contains scroller handles to move
around in the bitmap. Usually, the bitmap will be four times as large
as the screen the window opens upon.
amiga_low
Renders into a low-resolution custom screen.
amiga_high
Renders into a high-resolution custom screen.
amiga_super
Renders into a super-high-resolution custom screen.
amiga_a2024¹
Renders into an A2024 resolution custom screen.
amiga_printer
Outputs pages on the currently configured preferences printer.
Respects density and resolution settings. Requires a lot of memory to
run.
amiga_ilbm¹
Will prompt for a file name to save the current page contents to. The
page will be saved as a standard IFF-ILBM picture, including DPI
information, suitable for postprocessing using standard image
processing and editing software.
¹) Monochrome output only
Properties
----------
With Ghostscript 2.6.1 one can specify several driver specific options on
the command line. As for the Amiga drivers, they support the following
properties:
- PageWidth and PageHeight
The dimensions of the page to render into. The physical page size
Ghostscript will use for rendering is limited by these dimensions. On
startup The Amiga drivers will default to a page size roughly equivalent
to A4 unless different dimensions are specified. The size definitions may
include measuring units (e.g. "-sPageWidth=21cm"), the following units
are supported: pt (points, the default if no unit is given), pc (picas),
in (inches), cm (centimeters), mm (millimeters), dd (didot points), cc
(ciceros).
- OutputFile
The amiga_ilbm device pays attention to this property, which it will use
to construct the output file names for pages to be saved with. Thus,
`-sOutputFile="ram:page"' yields the files "ram:page0001.ilbm",
"ram:page0002.ilbm", etc.
Not all devices will pay attention to DPI page resolutions.
Installing fonts
----------------
The Ghostscript distribution includes a number of public-domain or
otherwise freely distributable fonts. However, these are mostly of poor
quality. In order to install a new font or to replace a font with a
different one, the following steps are required:
1. The font must be converted to Ghostscript format. For font files in
BDF-format (such as the fonts included in the X-Windows distribution)
this requires processing with the "bdftops" script file (syntax is
"bdftops <Source file> <Destination file>"). Fonts in standard ASCII text
format (".PFA" format) or packed binary file format (".PFB" format), such
as most Adobe-Type-1 hinted outline fonts to be purchased from various
vendors, need not be converted as this is the native format Ghostscript
expects.
2. Copy the resulting output file to the "ghostscript:fonts" drawer, choose
a suitable name (see the file "ghostscript:fontmap" for more
information).
3. Edit the file "ghostscript:fontmap" to include the font which will make
it visible to the interpreter. Read this file carefully as it gives basic
hints how to name a font file and how to edit the corresponding font
entry.
The Workbench window
--------------------
The default output device (the Workbench window) can be controlled both by
mouse and by keyboard:
Cursor keys will move the currently visible area of the page, holding
down a Shift or Control key will increase the size of the scrolling
steps.
Control+C and Escape will send the interpreter a signal to terminate
processing, so does clicking the window close button.
By default the page size will always be four times as large as the
currently visible portion of the Workbench screen, see the section entitled
"Page sizes and resolutions" for more information.
Troubleshooting
---------------
This interpreter implementation requires a lot of chip memory to run. In
order to assure that enough memory will be available, close any Workbench
drawers or Shell windows which are not necessarily require to run the
interpreter.
Most Postscript documents use hard-coded document page sizes, i.e. the
output page size will not be scaled to fit the currently set output page
size. In these cases you may want to make use of the Postscript "scale"
operator. Say, you wish to preview the file "butterfly.ps" in just half its
size. Enter "0.5 dup scale" and press return, now enter "(butterfly.ps)
run" and press return; et voilà: the butterfly will be rendered just half
as large as usual.
Some documents, such as "porsche.ps", contain no "showpage" command to
finish the batch job. In this case, type "showpage" and press return or
enter "erasepage" and press return to clear the page.
About the Amiga port
--------------------
This port is based on Ghostscript 2.6.1. It was implemented using GCC
2.3.3, so you will have to refer to the file "COPYING" for copying and
licensing information.
This Amiga port was created by:
Olaf `Olsen' Barthel
Brabeckstrasse 35
D-30559 Hannover
Federal Republic of Germany
eMail: olsen@sourcery.han.de
o.barthel@a-link-h.comlink.de
The source code is included in the "amiga-src" drawer.
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