October, 1986                                                    AMIGAZINE!


                          MacPaint Viewer Program
                               MacView V1.01
                           by Scott P. Evernden
                          =======================

MacView allows you to view a standard MacPaint picture file on your Amiga.
You can look at the image in either of Amiga's low resolution (320 x 200
pixels) or high resolution (640 x 400 pixels) modes.  Because the Macintosh
utilizes square pixels, only these 2 view modes are supported, since they
result in the squarest pixels available on the Amiga.  You can switch modes
while the program is running.

MacPaint images measure 576 x 720 pixels, so it is clearly not possible to
look at the entire MacPainting at once.  For this reason, MacView provides
1 (in hi-res) or 2 (in lo-res) thumbing bars to allow you to pan around in
the larger MacPaint image.

This program uses a fixed color palette of black on white to replicate the
appearance of the Mac screen.  Sorry, I provided no way to change this.

In addition, MacView provides you with the ability to "snapshot" your
current screen into an IFF paint file.  IFF paint files are used by
DeluxePaint, Aegis Images, and Graphicraft, and should be compatible with
other and future Amiga paint programs.  Once you have produced the IFF
file(s), you can leave MacView, start up your favorite paint program, and
load the image.  At this point, you will have available the full range of
your paint program's capabilities to alter the picture.  Nothing could be
simpler!  The editors of AMIGAZINE! have provided you with a dummy icon
which you can copy, and rename to match the name of your new hi-res IFF
picture.  This will let you view your new IFF version right away if the
program SeeAll is in the root directory of the same disk.  EmptyIFF is a
dummy icon with no file associated with it.

Using MacView
=============
MacView can be run from either the Workbench or CLI.  From Workbench, simply
open the MacView icon, and you will see an empty painting.  You will need
to use the PROJECT menu to indicate a file to be opened for viewing.
Alternatively, from the workbench, you can open any of the MacPaint image
files, and MacView will run displaying that file's contents.  Use the latter
method here.

From CLI, simply incant "MacView filename" to get a hi-res screen of the Mac 
painting.  The filename is optional.  Also, from CLI, MacView will accept a
number of "switches" to control its default operation.  These can be listed
by typing "MacView ?" for the switch list.  Current switches support:
starting up in low vs. hi res (-l or -h; hi-res (-h) is by default);
control of whether MacView outputs compressed vs non-compressed IFF files
(-c or -n; compress (-c) is the default).

You can load new Mac files using the PROJECT menu; you also use this menu to
output the IFF files to be subsequently loaded into your Amiga paint program.

The VIEW MODES menu allows you to alternate between low and high resolution
on-the-fly.

General Notes
=============
This is an early version of this program.  I welcome (nay, encourage)
comments and criticisms in order to improve it in any way.  Most of my
testing has occurred under CLI, so please let me know if you experience any
anomolies.

I had little to go on in trying to figure out if a MacPaint file really came
from MacPaint.  I still do not know the format of the header except there
appear to be two different formats.  One (older?) format has a 512 byte
header starting with a long 2; another format holds a 640 byte header, and
contains the characters "PNTGMPNT" starting at the 65'th byte.  If neither of
these criteria is met, MacView will indicate that the file doesn't look like
a MacPaint file.  Both header formats also appear to contain the fill
patterns, which this program makes no use of.  If you know more, please let
me know.  This program should correctly operate on MacPaint files which have
NOT been chopped due to XMODEM funnies, so start downloading by modem or
transferring by null-modem at your convenience.  Digital Creations, an Amiga
developer in Sacramento, California, can supply you with Mac to Amiga
software and/or a null-modem cable.  You can call them at (916) 344-4825 and
ask them about Digital Link.  Check with your Amiga dealer first to see if
they have something comparable in stock.  Otherwise, a good terminal program
will handle the job.

When producing files for import into Aegis Images, you will need to name the
IFF files with a ".pic" suffix (like "fish.pic"), since Images will only
list and read paintings with this extension.  Also, Images DOES NOT accept
hi-res IFF at this time, so don't bother trying.  If you use Graphicraft,
then you will need to run MacView from CLI, and use the -n switch, since
Graphicraft doesn't understand compressed IFF files.  Graphicraft, like
Images, also can't handle hi-res pictures.

The MacView Program may be freely distributed and given away to anyone who
can make use of it.


All correspondence, suggestions, and donations can be directed to:

   Scott P. Evernden
   9 Courtland St.
   Holliston, MA 01746