Cream of the Crop 3/Cream of the Crop 3.iso/utility/picbot20.zip/PICBOOT.MAN

Text File | 1994-03-29 | 19KB | 501 lines

   This file describes PicBoot, version 2.0, a program to show an IFF
ILBM or GIF picture during boot.

Introduction
************

   Have you removed all output in your 2.0+ startup, and only see a
black screen during boot? Wouldn't it be nice to have a picture
instead? A picture that disappeared when the Workbench screen opened?

   If so, PicBoot is certainly a program for you. What it will do is
to read any IFF file containing an ILBM picture - or a GIF file - and
show that picture. As soon as the Workbench screen appears (or you press
any mouse-button), the picture will go away.

   Features:

   *  Fast picture unpacking, using highly optimized assembler. The
     entire picture is read into memory and then unpacked. This applies
     both to the IFF and the GIF unpacker.

   *  Optional auto-detaching; the picture is loaded as fast as
     possible, with minimal memory fragmentation.

   *  Random select among any number of pictures.

   *  Force a certain display mode for a picture, even if saved with
     another (can be selected on a picture by picture basis, if you are
     using a LIST file (see LIST).

   *  Optional screen centering (horisontally).

System requirements
*******************

   Apart from OS 2.04+, PicBoot doesn't require any special
libraries. The only non-ROM library required is iffparse.library
(which normally resides in Libs:).

Legal information
*****************

   This program is freeware. You may copy and use this program freely,
as long as the following conditions are met:

   *  All files are copied in an unmodified state. If additional
     information is needed, place it in a separate file. Preferably
     redistribute in the original archive form (*.Lha).

   *  The copying is done on a non-commercial and non-profit basis
     only. A copy fee to cover media costs, postage etc. may be
     charged. This fee may not exceed the fee to obtain an AmigaLibDisk
     from Fred Fish.

   *  The copier/spreader is not claiming the Copyright ⌐ of this
     program.

   Any exceptions from these restrictions requires written permission
from the author, Magnus Holmgren.

Disclaimer
==========

   Magnus Holmgren neither assume nor accept any responsibility for the
use or misuse of these programs. He also will not be held liable for
damages or any compensation due to loss of profit or any other damages
arising out of the use, or inability to use these programs.

   Magnus Holmgren will not be liable for any damage arising from the
failure of these programs to perform as described, or any destruction
of other programs or data residing on a system attempting to run the
programs. While he know of no damaging errors, the user of these
programs uses it at his or her own risk.

Usage
*****

   To activate PicBoot, add a line to your S:Startup-Sequence,
looking something like this:

     PicBoot Pics:Hi-res/Calvin01.Pic DETACH

Or, if you have a list of files in "Work:Text/PicList":

     PicBoot Work:Text/PicList LIST DETACH

   This line should be located near the beginning in the
S:Startup-Sequence (no point in placing it near the LoadWB
command, is it? :), but keep it after SetPatch. PicBoot will only
output any text if it fails, so don't re-direct its output. Note however
that if you place PicBoot before any additional monitors are
installed, you'll be stuck with the default.monitor for showing your
picture.  The DEFAULT switch may be of help here.

   Make sure no program makes any output in the CLI window, since then
the Workbench screen will open with a boring CLI-window instead...

   Options:

FILES
=====

   This is the only required argument. Here you specify the name of the
picture you want to view. You may enter several files here, in which
case PicBoot will select one of them randomly, and show that one. It
may also be the name of an ASCII file containing a filename list if you
specified the LIST option (see LIST).

       Note: The random-number generator used is quite simple, and is
based on the current system time. I don't know if it is a "good" random
generator.  It seems to be enough random for me at least.. :) If you
have an algorithm you think is better, don't be afraid to send it to
me. It should be fairly small.. :)

MODEID
======

   Short form: M

   NOTE: This argument is mainly for the more "advanced" user.

   This argument should be a decimal number specifying which
displaymode to use.  It basically replaces the so called CAMG hunk in
an ILBM file.  Thus, you must select mode with care, or else the
picture will look like trash (nothing more serious can happen. I hope!
:). When showing GIF files, it will override the internal "best mode"
routines (which aren't good at all. But I haven't bothered to add code
to make them better.. :).

   To make it easier for you to find out which display mode id to use,
there is a small program called GetModeID included, which uses the
ReqTools or Asl screenmode requester. Simply select the display
mode you want. See GetModeID.

   The mode id will be passed through the same validity checking as a
normal so called CAMG chunk, so PicBoot should handle bad values
properly (although I haven't tested this much.. :).

LIST
====

   Short form: L

   If this switch is specified, PicBoot will interpret the files in
the FILES argument as names of files containing a list of pictures (or
rather, argument lines). PicBoot will then randomly select one of the
lines in the selected file, and process it almost like a normal
argument line. The only difference is that you can't use the DETACH
argument. This argument may not be specified in a listfile (no point in
doing it anyway).

   The filelist file is an ASCII (text) file with a simple layout. On
the first line you specify the number of argument lines in the file.
This is usually <number of lines in file>-2 (one line is occupied by
the count, and the other is the last linefeed). The rest of the file is
simply the argument lines to choose from.

     4
     Work:Pics/Comics/Calvin01.Pic CENTER ON
     Work:Pics/Comics/Calvin02.Pic MODEID 137220
     Work:Pics/Comics/Calvin03.Gif
     Work:Text/MoreCalvins.txt LIST CENTER ON

   The first file will be centered (regardless of what the command line
said).

   The second file have a display mode id added to it. This particular
id tells PicBoot to use the PAL monitor, with a low-res interlace HAM
screen. If no id is specified, PicBoot will use the MODEID specified
in any previous "listfile line", the CLI-arguments, or the contents of
the CAMG chunk/"best mode" (in that order).

   The last example line is another list file, which PicBoot will
load and process. Centering will be on as default for all files in this
list.

   Note that any arguments specified from the CLI, or in any previous
listfile, will be taken as the new default value. In the listfile you
may alter this default. This does not include the LIST argument
(ofcourse). It is always turned off before parsing a line.

       Warning: Since you may enter a new listfile within a listfile,
you can be caught in an endless loop, constantly changing (maybe to the
same) listfile. No checking for this is done. Also, since there is no
CLI-window around, you have no chance to send PicBoot any CTRL-c, if
PicBoot should happen to listen to this. You have been warned! :)

       Note: A line in a listfile may not be more than 510 chars, or
it will be truncated when read. This shouldn't cause any problems I
think..

DETACH
======

   Short form: D

   If this switch is specified, PicBoot will detach from its calling
CLI when the picture is fully loaded and displayed. If you specify this
option, you shouldn't "Run" PicBoot. This option will reduce memory
fragmentation, and will ensure that the picture gets loaded quickly.
However, the implementation maybe isn't the most "system-friendly" one
(but there aren't that many alternatives), hence the switch. I don't
think there will be any problems, but one can never know... :)

CENTER
======

   Short form: C

   Possible arguments: YES, ON, NO, OFF. Default is NO.

   If this switch is on (argument is YES or ON), PicBoot will center
the picture. This centering should work fine for most screen modes, but
one can never now.. :) If a screen promotor is active, then
PicBoot can get it wrong (when the screen is opened in another
mode than PicBoot had asked for).

DEFAULT
=======

   Short form: DEF

   Possible arguments: YES, ON, NO, OFF. Default is NO.

   If this switch is on (argument is YES or ON), PicBoot will force
the picture to use the default.monitor, regardless of what was actually
stored in the picture (in the CAMG chunk). This is needed since very
early in the startup, default.monitor is the only monitor available
(e.g.  multiscan.monitor is normally not available). In the future, I
might add more types of "forcing" (e.g. force a picture to PAL, NTSC or
whatever that might be useful).

   This switch also acts on the MODEID parameter, if specified.

AUTOSCROLL
==========

   Short form: AS

   Possible arguments: YES, ON, NO, OFF. Default is NO.

   If this switch is on (argument is YES or ON), the OS 2.0+
autoscrolling of screens will be enabled.

       Note: During boot, this switch may make the actual display a
bit smaller than normally possible. There is nothing I can do about
that... :) You can, however, by ensuring that ENV: is properly set up
before PicBoot is started. Or you could try the VIDEOOVERSCAN switch
(see VIDEOOVERSCAN).

VIDEOOVERSCAN
=============

   Short form: VO

   Possible arguments: YES, ON, NO, OFF. Default is NO.

   If this switch is on (argument is YES or ON), the visible size of
the opened screen will be as large as the system can handle. Forces
AUTOSCROLL to YES.

Known problems
**************

   I do not know of any real bugs in PicBoot. However, certain parts
of the program may still contain bugs. E.g.,  pictures that have a mask
bitplane (mskHasMask) are supported, but since I only have one
(compressed) picture that have a mask, there might be a bug in that
code (can't test it properly).  Please report any problems!

   Currently there is no support for SHAM, PCHG and similar "special"
pictures. I'm not sure if this could be implemented in a "clean" way
(that would work on future systems etc). These pictures aren't that
common, and I have an Amiga with AA-graphics, so... :) Color cycling is
currently ignored (I have no need for it).

   Interlaced GIF pictures aren't supported, since I don't have any such
picture. Besides, the decompression of such pictures would be slower
anyway.

       PicBoot doesn't remap GIF files in any way. Even if you have
ECS, GIF files can still be useful. This is because a GIF file can have
from 2 to 256 colors (inclusive). Thus, if you have a program that can
save a 32-color picture as a 32-color GIF file, there will be no
problem to view it with PicBoot.

   The "best mode" routine used in the GIF reader isn't good at all
(this includes the ROM function in OS 3.0+! :).

   Pictures with more than 8 bitplanes are currently not supported by
PicBoot.

   The centering for (some?) Super72 screens doesn't work. I suspect
this is an OS-bug (I know that PicBoot calculates a reasonable
offset, which Intuition seems to ignore).

GetModeID
*********

       GetModeID is a simle program that shows a Asl or
ReqTools screenmode requester, whichever is available. The program
will then print out the decimal identifier for the selected screenmode,
suitable for use together with the MODEID parameter. This program can
only be used from a Shell. Example usage:

       PicBoot Island.Gif `GetModeID`

   This will first show a screenmode requester (if you have one, that
is), and then show the GIF-picture in the selected screenmode.

UnpackILBM
**********

       UnpackILBM is another simple program (at least in theory...
:). It will take any IFF ILBM picture and unpack the so called BODY
chunk in it (this is the actual image data). This means that e.g.
PicBoot will be able to display that image a little faster, at
least if loading them from some fast media. Or, if you use
PPShow/ShowIFF, you could repack the picture with
PowerPacker/Xpk, to maximize the compression (as the
compression used in IFF ILBM isn't a very efficient one. But on the
other hand, it is rather fast). But then PicBoot won't be able to
load them.. :) Example usage:

       UnpackILBM Island.Pic Island.Pic.NoComp
       UnpackILBM Island.Pic

   The first example till unpack the picture to a new one, while the
other will - via a temprary file - overwrite the original picture with
the uncompressed version.

   I wrote this program since someone (I've forgot who) wanted it... :)

       Note: I haven't tested this program that much. I've
converted a few pictures, so it seems to work fine (at least when there
aren't any errors), but one can never now.. Please report any problems!

       Note: This program doesn't strip any information. All chunks
will remain. The picture data is only decompressed.

Author contact
**************

       PicBoot was written in 100% assembler by Magnus Holmgren. If
you have any comments etc, feel free to send me a note. You can reach
me via internet on this address:

     [e-mail]

   Fido-net messages should go to "Magnus Holmgren",
2:204/[e-mail].  Snail mail should reach me if you write the
following address on the envelope:

     Magnus Holmgren
     RydsvΣgen 254  A:14
     S-582 51  Link÷ping
     SWEDEN

Version history
***************

Version 1.00
============

   Release date: 08 Feb 93

   *  Initial release.

Version 1.01
============

   Release date: 14 Feb 93

   *  PicBoot would sometimes read past the end of the picture-list
     file, although the file was correct. Also, the last picture would
     never be showed.  Fixed (thanks to Daniel Joseph Oak for
     reporting).

   *  Did some tweeking, to make the program smaller. The total gain
     was eaten up by improved error messages though. PicBoot will now
     more accurately report why the display didn't open.

   *  Added support for masked ILBMs, since I discovered that I had
     such a picture anyway. :) Since I only have one picture, its hard
     to tell if it really works, but it seems to be ok at least.

   *  The autoscrolling of the screen didn't work. Fixed (so now you
     can view pictures larger than the screen, by moving the invisible
     mouse-pointer).

   *  Added the CENTER switch.

Version 1.02
============

   Release date: 21 Feb 93

   *  Added the DEFAULT switch. As Bradley Yen pointed out for me,
     there is (normally) only one monitor available early in the
     startup, and that is default.monitor (and what default.monitor is
     can vary. It can e.g. be PAL or NTSC). This switch will make the
     picture use the default.monitor, regardless what it was saved in.

   *  Autoscrolling of screen disabled again, since this would make some
     overscanned pictures clipped, even if this wasn't needed.

   *  A bug in the init code fixed.

Version 1.03
============

     Release date: 15 Oct 93

   *  If an error occured, any black "cover screen" (BLACK option)
     wasn't closed.  Fixed.

   *  "Ported" to Macro68. At the same time, the code was cleaned up a
     little. All this saved more than 100 bytes from the program. Most
     of it eaten up by the improvements though.. :)

   *  Added the MODEID parameter. rtGetModeID is included to make the
     use of this parameter easier.

   *  Docs rewritten using Texinfo.

   *  Pictures with mskHasMask were reported to have an "error in
     compressed BODY chunk", due to a bug. Sorry, but I don't have many
     pictures to test this code with.. :)

   *  AUTOSCROLL switch added, so that you can scroll around in large
     pictures.  Mostly useful when PicBoot is used from the Shell.
     During boot, this can cause the picture to be clipped when it
     isn't necessary.

   *  PicBoot will now move the screen to the back before closing it
     (this makes the closing faster). Not needed during boot, but... :)

   *  List files much improved! Each line will be parsed almost like
     the normal arguments. Old files should work fine, as long as no
     filename contains spaces, in which case those lines need to be
     quoted.

   *  Altered command line syntax slightly. Needed because of the new
     listfile format. Tech note: I'm using a poorly documented feature
     of AmigaDOS: The /T specifier. If the argument following the
     keyword is YES or ON, the switch is turned on, if it is OFF or NO,
     the switch is off. Any other arguments causes an error. Testing
     revealed the true nature of this specifier... :)

   *  Removed the "You need OS 2.04+" error message. An (Exec) Alert
     will be shown instead.

   *  PicBoot will now random-select among the FILES arguments, even
     if the LIST argument have been used (previously, only the first
     file was used).

   *  VIDEOOVERSCAN switch added. Makes the visible area as large as
     the system can handle. Requested by Stefan Boberg.

   *  Screen centering improved. Should work fine with any screen mode
     now (but if you promote the screen, PicBoot will probably get it
     wrong. Unless the promotor also "promotes" QueryOverscan() :).

Version 2.0
===========

   Release date: 29 Mar 94

   *  BLACK argument removed. Not needed any more, since PicBoot now
     will first allocate the needed memory, decode the picture into
     this memory, and then open the screen. This makes the screen
     opening/closing a little faster too (practically instaneous on my
     A4000/040).

   *  Pictures (or rather, brushes) that were less than 16 pixels wide
     wouldn't decompress properly... :)

   *  Added support for the CMAPOK flag in the BitMapHeader.bmh_Flags
     (previously called bmh_Pad) field (if this flag is set it
     indicates that the color map contains 8 bits/color rather than 4
     bits/color).

   *  Major code cleanup. Made the program somewhat larger, but... :)

   *  GIF support added. Should be a little faster than PPShow.. :)

   *  The MODEID argument wasn't properly "passed on" to any following
     listfile(s).

   *  Rewrote rtGetModeID into GetModeID, that first checks for
     Asl, and then tries with ReqTools before giving up. This new
     version is in C, compiled with DICE, without any startup code, and
     is fully residentable. :)

   *  Included UnpackILBM, that takes any IFF ILBM file (with a BODY
     chunk, i.e. a normal picture) and writes it with an uncompressed
     BODY instead. Written upon user request..