Atari Mega Archive 1/Atari Mega Archive - Volume 1.iso/ste/scrth.zoo/scrlthun.doc

Text File | 1993-05-23 | 8KB | 149 lines

                    S C R O L L I N G   T H U N D E R
                         Text File Viewer  v1.0
                            by Ken Newman

                             DEMO VERSION


Scrolling Thunder is a viewer or browser for text files (actually, any kind
of file) with a difference. It exclusively uses hardware smooth scrolling,
available only on STe/MegaSTe/TT/Falcon, to produce the smoothest, fastest
display of text you've ever seen. It scrolls forward or backward at variable
speed, and is almost entirely mouse-controlled. It is completely free of
the restrictions that annoy me about virtually all other text viewers. There
is NO limit on line length (and I mean no limit - you can give it a binary
file if you want), no fixed tab size, or fixed end-of-line character
requirements. It can load fonts and search for strings, is compact and
unbelievably fast. The user interface was the primary design consideration -
it's effortless and requires very little to control it. It uses the entire
screen and displays full-sized characters, which makes text much more
readable (and faster to draw) than vdi text in a window. After seeing smooth
flowing text for a while, everything else looks jerky! It's amazing how bad
the desktop Show function looks for example after using Scrolling Thunder.
The effect is not unlike the scrolling credits at the end of a movie.

There are two versions of Scrolling Thunder, colour and mono, that together
will work on all current machines and monitors *that have hardware smooth
scrolling* - TT/Falcon will have to use ST medium or high resolutions. The
program does NOT work on regular ST/STfm/MegaST systems. Scrolling Thunder
is shareware; I spent a lot of time writing and testing it and I think my
time is worth something. So although I'd rather that I didn't have to do it
this way, the programs as distributed are demo versions, which are almost
fully functional, but have some disabled features. To get the full
unrestricted versions, you will have to send me a miniscule payment, and
I will send back a disk. More details at the end of this file.


Features
========

To use the demo version, pick either the colour or mono one, and run it
from the desktop (it can also be used from a command-line shell such as
Gulam). You get a file selector, pick a text file. Don't move the mouse
very far, it makes the text flow up or down! The vertical movement of the
mouse controls whether the text scrolls forward, backward, or stays still.
The further up or down you move the mouse, the faster the text moves.
Neat, huh?

The program understands just a few keys and both mouse buttons are used
for major actions. Click and release the right mouse button - a dialog
pops up with all the options in the program. The box at the top holds the
file name and the percentage of the file that has been drawn into memory
so far. The line terminator section lets you pick either CR+LF/LF or CR.
The former (the default) works for ST, IBM, and Unix format text files,
the latter works for Mac format files. (Too bad these all had to be
different formats!) The tab size lets you type in any tab width (units are
characters). The screen buffers section lets you control the amount of
memory the program uses - CAUTION, this program can use a LOT of memory
if you set this too high. More on the use of this number later.

There is a button for loading a new font - Scrolling Thunder understands
only Degas Elite format fonts, not GDOS fonts, which are much too slow
to draw anyway. The demo version comes with two colour and two mono Degas
fonts - if you register I'll include several more of each type. Actually,
you can load colour fonts in mono and vice versa - but they usually don't
look very good that way. There is a button for saving a config file, which
contains all the settings from the option dialog except the line terminators.
However, this button is disabled in the demo version. Normally, this lets
you set how the program works when it starts up, saving you from setting
it manually every time.

There are three ways of leaving the options dialog - Exit, Cancel, and Ok.
Exit just quits the program. Cancel closes the dialog and does nothing.
Ok causes all of your changes to take effect, and resets the file position
to the beginning of the file.

Click and release the left mouse button - if you started Scrolling Thunder
from the desktop, you get a file selector from which you can choose another
file to look at. The Cancel button in the file selector will also exit
the program. If you started the program from a command-line shell, you
do not get a file selector, instead it automatically switches to the next
file you gave on the command line (if any). With desktops that properly
change the working directory to the one containing the program, you can
use Install Application or equivalent. Note this works properly only on
very recent TOS ROMs - like 2.06 or 3.06 (not 1.6). The drag and drop
feature of some desktops should work also (not tested).

Now the keys - the Alternate key restarts you back at the beginning of the
current file. The Left Shift key brings up the Search String dialog, which
lets you type in a string to search for. If you type something, and pick Ok,
that string is searched for *always starting at the beginning of the file*,
and without regard for case (i.e. case insensitive). From then on, the mouse
buttons control the search. The left mouse button finds the next occurrence
of the same string, and the right mouse button quits the search and leaves
you where you are in the file. When the string is found in the file, the
line with the match is shown at the top of the screen. However the search
ends, either by you quitting or the string not being found, the bell sounds,
and normal scrolling resumes. You cannot scroll while searching. Sometimes
when searching you will notice a screen of text appearing briefly that
doesn't contain your string on the top line - the busy bee cursor appears
however to indicate this is a temporary screen, this is done because of the
algorithm used to draw text and is normal.


Memory usage
============

The screen buffers section in the option dialog lets you choose how much
memory the program will use. Note the number is in *screens*, so if you
set this too high, you can end up using a LOT of memory. There is also
a bit of overhead used on top of this amount, so if you don't have much
memory in your computer (512K or 1M) keep this number down. Why is it
adjustable? The bigger it is, the more text can be drawn into memory and
scrolled without redrawing text, which is very fast but produces a small
delay. A large number will keep even big files completely rendered into
memory, and will let you scroll over it with zero delays. The smaller the
screen buffers number is, the less memory will be used, but the program
will pause very slightly to redraw text at certain intervals. So it's a
tradeoff, whichever seems better to you, I didn't pick one extreme or
the other. If you pick a number too big for your machine, you will get
an error message - pick a smaller size. On a 4M machine, you can go all
the way to 99 screens, but this is a bit silly, as this is several meg
of RAM!


Registering
===========

The demo versions have the Save Config button disabled and in addition
will only display the first 5K or so of text from any file. This lets you
get a feel for the program but gives some incentive to send in your
payment and get the full version. The price is CDN$15, or US$12, which
to me seems pretty reasonable. The full version includes several more
Degas fonts as well. Once I figure out how the Compuserve shareware
registration feature works, you will be able to register that way too. 8^}

Payment can be sent to me at

            Ken Newman
            425 Mill Rd.,
            Unit 13,
            Etobicoke, Ont.,
            Canada
            M9C 1Z2


I can be reached on Compuserve as 72437,1275 or on Usenet as [e-mail].