Belgian Amiga Club - ADF Collection/BS1 part 34.zip/BS1 part 34/Mac-2-dos v1.1b.adf/Mac Utilities/Giffer/Giffer.doc

Text File | 1989-10-02 | 16KB | 363 lines

Giffer 1.06

Steve Blackstock
40 Bartlett Ave
Lexington, MA 02173

Giffer version 1.06  (July, 1989)

Giffer? is an image display program for the Macintosh II.  Giffer is
Copyright 1988, 89 Stephen Blackstock, and I reserve all rights to its
distribution and sale.

Giffer is Beerware?.  If you like it and use it, please send me a case of
beer (or $20  so I can buy one).  If you do send me something, I'll make
you a registered user of Giffer, and that will entitle you to receive
news about Giffer updates.  I plan to work on Giffer a lot more, so this
update news might be beneficial if you like the program.

Giffer 1.06 is not a significant change from Giffer 1.0 (released
November, 1987).  It is mainly a bug-fix release.  Since the release of
System 6.0.2 (and even before that), I have gotten many complaints of
Giffer's crankiness and tendency to bomb, especially under MultiFinder.
I have tried to correct some of the problems in version 1.0 in this
release.  Differences from 1.0 include much better MultiFinder
compatibility, better memory management, more readable PICT files, and
32-bit Quickdraw capability.  This is by no means the overhaul I have
been working on for the program.  Work on a more powerful Giffer has been
seriously delayed by my need to make a living.  I still hope to get a
major upgrade out, although it could be in an altogether different
program.

Version 1.06 is compatible with 32-Bit Quickdraw and MultiFinder.  It
fixes several memory-related bugs, the "discolored desktop" problem, and
the "no invisible resize box" bug.

What the heck is Giffer?

As I said before, Giffer is an image display program.  It works only on
the Macintosh II.  It works best with 256 colors, but will work with any
number below that, and should work with more than that, although I
haven't tested it with more than 256 colors.  It is a memory-intensive
program, so it's nice to have as much memory as you can get to run it.
However, it will run with the standard 1 Meg.

I wrote Giffer as a utility to display images stored in GIF, or Graphics
Interchange Format.  GIF is a graphics compression and storage standard
developed and Copyrighted by CompuServ Information Service and H&R Block
Company.  It is useful for storing color images of arbitrary size in a
form that in completely computer-independent and with a compression
scheme that allows file sizes to be just fractions of image sizes.  GIF
files can be created and viewed on any computer for which there is a
program written to do it.  Currently, the Macintosh II is about the best
personal computer for displaying color graphics, so it is an excellent
machine on which to view GIF images.

In addition to GIF files, Giffer can display and encode PICT files (the
kind MacDraw can produce), PICT resources with ID=0 (the kind you can use
for a Startup Screen on the Mac II),  and QDV files.  QDV format is a
simple color image storage format I developed which does not use
compression.  You normally won't ever need to use it.  (If you do, I'll
be glad to give you the information you need to use it.  You just need to
contact me.)  Giffer can also READ, but not WRITE, ThunderScan SCAN image
files.

Here's a brief summary of the different types:

- GIF

Graphics Interchange Format, an image compression and encoding standard
developed by CompuServe Information Service.



- ThunderScan Scan Image

Scan Image files are produced by ThunderScan digitization hardware and
software.  They hold 32 gray levels of information per pixel.
ThunderScan is produced and trademarked by ThunderWare, Inc.



- QDV

These files are used mainly by myself and a few others who wish to
display very simply-encoded color images.  The format will not be of
interest to most users of Giffer.  However, anyone interested in QDV
format may obtain the necessary information by contacting me.



- picture resource ID=0

Files which have a resource of type PICT with ID=0 are displayable with
Giffer.  A Macintosh II StartupScreen document is such a file.  Giffer
will handle files generated by GrayView, another image-display program,
written by David Fry, because these files use this format.



- PICT (data fork)

The standard way to save most graphics objects in files on the Macintosh
is by using a PICT data file.  This is the type file you can generate
with most drawing and painting programs available for the Macintosh.  It
is also readable by these programs.  Giffer can also save in this format
so that  images can be viewed and even manipulated with other software.


How can I get GIF images?

There are currently (7/89) over 5000 GIF files in the data libraries in
the Pictures Support Forum (GO GALLERY) on CompuServe.  This forum is
where GIF started and is developing.  If you download files from this
area, make sure that you don't strip any characters (such as non-printing
characters) from the files!  Many communications programs for the
Macintosh will believe that GIF files are TEXT files, since they are not
encoded in the standard MacBinary format, because they are not
Macintosh-specific files.  If your communications software strips
non-printing characters from these files, what you will end up with is
something you can't use at all.  This can be a waste of time and money,
so it's worth being careful about.  Some GIF files may also be available
on other on-line services or from public domain libraries in computer
user groups.  However, CompuServe is certainly the first place to look.



What do I do once I have images to look at?

Run Giffer!  Under the file menu, choose the correct Open command (Open
GIF file... for GIF files), choose the correct file, and you're on your
way!  If you don't see your file come up in the dialog box after you give
the Open command, try holding down the option key while you choose Open
from the menu.  This should display all the files on the disk, not just
the kinds that Giffer expects to find for that particular Open command.

If you open a GIF file, Giffer will read the file off disk and then put
up a little dialog box showing you the progress of the decompression.  As
soon as decompression is complete, a window will pop up, and your image
will be displayed.  For other types of images, the image will just be
displayed without any decompression progress indicator.



What else can I do with Giffer?

First, let me explain a little bit about how Giffer thinks and acts.

Every image that you view with Giffer will be two places: on the screen
in the window you're looking at, and in memory.  The image on the screen
is called the "windowed" image, and the one in memory is called the
"memorized" image.  They can be different!  When you first put up an
image on the screen, the memorized image will be the same as the windowed
image.  The windowed image can actually be larger than the screen, so you
might not actually see all of the windowed image.  You can do some
manipulating of the  windowed image: You can move it around, stretch it
in both directions, and shift scan lines in it.  However, what you do to
the windowed image has no effect on the memorized one.

Here's a brief summary of menu commands:

File Menu:

(Open commands)  use these to open the type of file you want.  If you
hold down the option key while selecting the menu, all files will appear
in the subsequent dialog box.

Klose  Use this command to close the frontmost window.  You can always do
this with the close box of the window, so this command is redundant.
But, it is useful in the few cases when you've pushed the front window's
title bar under the menu bar and, therefore, can't get at the close box.

Get Info Use this command to get some information about the memorized
image, like its dimensions and which colors it uses.

(Save commands)  Use these commands to save the memorized image to disk
in a specified format.  You will be saving the MEMORIZED image, not the
windowed image.  If you save as a GIF file, you will be presented a
dialog box showing you the progress of GIF compression.  You might need
to be patient here.  Compression can take a while, and sometimes does.

Remember that saving saves the memorized image.  If you try to save when
the memorized image and the windowed image are different, Giffer will let
you know and give you a chance to do something about it.



Edit Menu:

Copy  Use this command to copy the entire frontmost image to the
Clipboard.  You can then paste into a new Giffer window or even into
another application.

Paste  Use this command to paste the contents of the Clipboard into a new
window.  In this way, you might copy an image from another program and
paste it into Giffer in order to make a GIF document out of it.

Giffer does not now, but soon should, support cutting and pasting of
parts of windows.



TouchUp Menu:

Zoom...  Use this command to change the size of the windowed image.  The
windowed image can be as large as 16384 x 16384 (pixels).  You can
specify either an exact width and height, or you can choose to quarter,
half, double, or quadruple the image size.  For some shortcuts, you can
use the keyboard:

F1 (extended keyboard)..........Quarter

F2 or Command-[left arrow]....Half

F3 or Command-[right arrow]..Double

F4...................................Quadruple

[home] or Spacebar...............Revert



Revert means revert to the size of the memorized image.

Be aware that zooming takes the MEMORIZED image and plops it into a
window of the size you suggest.  The windowed image is lost unless you
explicitly memorize it.

Shift Scan line...  Use this command if you want to move a horizontal row
of pixels to the right or left.  This feature is useful especially with
ThunderScanned images, because, they often have a few scan lines which
are slightly out of alignment.

Once you select this command, the cursor will dissappear and you will see
a highlighted horizontal line that moves up and down with your mouse.
Position it on the line you wish to shift, and then click.  You can now
use the arrow keys to move the line left or right, and click again when
you're done.  Be sure to memorize the image afterwards if you want to
save the change.

Use Default Palette  This command will force the frontmost window to be
redrawn with the Apple's "default" color palette.  This will usually
cause the image to look worse.  However, it is useful for creating
startup screens, because the StartupScreen mechanism will pay attention
only to the default colors.  It will not attempt to display an image in
the colors best suited to it.  Be aware that forcing a default palette
affects both the windowed and memorized images, and the action is
therefore irreversible.



ImageStorage Menu:

Memorize Image:  Use this command to copy the windowed image to the
memorized image.  If the windowed image extends off the screen, the new
memorized image will also.  You won't lose parts of the image you can't
see by using this command.



Effects Menu:

Window Closing Preferences  You can use this command to tell Giffer
whether or not to make a big deal out of closing a window.  Play around
with the options to decide what you like best.  Your selections will be
remembered the next time you run the program.

Miniaturize or Bring Back  Sometimes, especially if you have a lot of
memory and are able to open many files at once, your desktop will get so
cluttered with pictures that it's hard to find the window you're
interested in.  The miniaturization feature will help in these instances.
 Choosing the Miniaturize command will shrink the frontmost window and
send it off in an out of the way corner.  You can bring it back by
choosing Bring Back or by clicking on it's Zoom box.



Other things...

Window Sizing:  There is an invisible size box in the lower right corner
of each window.  You can click in it and drag to resize the window just
as you're used to with other Mac applications.  I chose to make the box
invisible so it wouldn't interfere with the picture.  But it's there.
However, if the bottom right corner of the window is not on the screen,
you won't be able to grasp it, of course.  In that case, you'll have to
use the Zoom command to size the window.

Extended Window Dragging:  If you hold down the option key and click on a
picture (except in the invisible size box region) the cursor will change
to an "extended dragger" cursor.  It will allow you to drag the window
without grasping the title bar.  This is sometimes necessary when the
window extends off the screen and you want to view the bottom of it.  If
you drag the title bar of the window, you'll be limited by the menu bar
in moving the window.  With the extended dragger, you can push most of
the window up under the menu bar, so you can see it's bottom.  Use this
feature with caution!  Pushing the title bar of a window out of your
visible area will make it so you can't see its close box or the
highlighting of the title bar that tells you it's the active window.







Can I distribute Giffer and GIF files in general?

You should feel free to distribute Giffer as much as you'd like.  I want
everyone who wants or needs it to be able to have it.  But please try to
distribute this documentation along with it.  And remember, Giffer is
Beerware.

Distribution of GIF files is a stickier issue.  GIF is a copyrighted
standard, and CompuServe reserves rights to it.  But, you should feel
free to distribute any images which you created and to which you can
claim authorship, even if you used Giffer to make GIF files out of them.
You should be careful about distributing GIF files that you obtain from
other sources.  Most of the files you download from CompuServe, for
instance, bear the statement: "GIF file for personal use only.
Distribution prohibited except under CIS guidelines."  This doesn't mean
that you can't redistribute these files at all;  it just means that you
need CompuServe's permission to do it.  They probably would love for the
files to be given to non-profit groups, but they probably would not like
you to be selling them.



What are Giffer and GIF good for?

Many people will use Giffer purely for its entertainment value.  It
offers its users a chance to see images that were created outside the
Macintosh world, and, with the right images, it can show off the display
capabilities of the Macintosh II in all it's glory.

However, Giffer, and GIF, can be used for things far beyond just
entertainment.  GIF's ability to store color images in highly compressed
format that is completely computer-independent is very powerful.  It will
allow people who work with graphics on different computers to be able to
port their graphics between those computers, and that ability is
certainly nothing to sneeze at!





Epilogue:

I am committed to doing further work on Giffer and fixing bugs that now
exist in the program.  Someday, Giffer will be a much more powerful
program. I will listen to anything you have to say to me regarding bugs,
suggestions for improvements or new ideas for implementation with
interested ears.  Please don't hesitate to drop me a line and tell me
your comlaints and wishes.

I should thank my beta-testers for helping me to debug Giffer and for
giving me some ideas.  They are, in no prticular order, David MacMakin,
Fred Fish, Price Collins, Bill Volk, Jay Weiss, and Keith Sproul.  Also,
thanks to Kevin Mitchell for some great icons and Karen Brothers for some
great moral support.  Finally, thanks to Alan, Sarah, Richard, and the
cats for putting up with my late-night hacking.