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The Original Shareware 1.1
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The Original Shareware (WeMake CDs)(Volume 1.1)(CDs, Inc)(1993).iso
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bwvid14.zip
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BWVID.DOC
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1986-06-01
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BWVID - Version 1.3, (C) Copyright 1985 by Scott W. Killen
All Rights Reserved
What BWVID is:
--------------
BWVID is an acronym for "Black and White Video". It is used
exclusively to correct problems surrounding the use of Black and White
monitors with the CGA (Color Graphics Adapter) card. These problems
may be characterized by "fuzzy" or unreadable screen displays. So, if
you have a color graphics board in you system, and you also have a
black and white monitor, then you need this program, otherwise you
don't.
To Install BWVID
----------------
After the DOS prompt, simply key in
DOS Prompt> BWVID
Once installed, Screen Cleaning may be invoked by pressing Alt-PrtSc
keys simultaneously. Pressing them a second time will terminate Screen
Cleaning. BWVID will beep the speaker twice when Screen Cleaning
begins and once when it ends.
How BWVID works:
----------------
BWVID uses two different methods to correct fuzzy displays. The first
is called "Filtering" and the second is "Screen Cleaning". Once BWVID
is invoked, filtering is always present. Screen Cleaning may be turned
on or off at the users option.
Filtering
BWVID interposes itself between the program that you are running and
the IBM BIOS programs to modify display requests for color. In effect,
each time a request is made for a particular color to be displayed on
screen, BWVID steps in and changes the request to White before
continuing.
The rule that BWVID follows to make this change is stated as:
IF foreground and background are the same THEN
IF they are black or white THEN leave them alone
ELSE they are another color so force to white
ELSE
IF foreground is black OR background is white THEN force "Reverse Video"
ELSE force "Normal Video"
Normal video is defined as White characters on Black background
Reverse video is defined as Black characters on White background
This technique will remove the fuzziness associated with most
applications programs that may be run. Once installed, the program
sits passively in the background and filters all color requests and
changes them as necessary, you do nothing else.
Screen Cleaning
There are a class of programs for which Filtering will not work, for
the simple reason that these programs do not use the IBM BIOS routines.
Instead, they write directly to video themselves. BWVID filtering
never gets a chance! In general, they do this to gain speed.
BWVID provides Screen Cleaning to remedy this additional situation. Of
course, the price to pay for this remedy is the very speed that the
program was trying to achieve. But, when faced with being not able to
use the program because the screen is unreadable, a slight decrease in
its speed doesn't seem so unattractive.
Speed is important though, and that's why BWVID provides the user with
the option of turning Screen Cleaning on or off at will.
In essence, Screen Cleaning proceeds along after the delinquent
application program and cleans up its mess. It does so by examining
each element displayed on the screen and correcting it as necessary.
To begin Screen Cleaning, you need only press the Alt-PrtSc keys
simultaneously. BWVID will announce that it has begun Screen Cleaning
with two short beeps of the speaker. Screen Cleaning may be turned off
by again pressing the Alt-PrtSc keys. BWVID will announce that Screen
Cleaning is no longer being performed with one short beep of the
speaker.
SCDEMO.COM is included to demonstrate Screen Cleaning. You need only
install BWVID, then type SCDEMO and follow directions to see how Screen
Cleaning works.
What BWVID can't remedy
-----------------------
Screen Cleaning always works. It will always create a screen that can
be read and understood. But some problems exist if Screen Cleaning is
requested while in a GRAPHICS mode. This especially affects
graphically oriented games.
This happens because some programs (especially games) expect the
display to be exactly the way they left it when they next try to write
to it.
Because Screen Cleaning modifies the display without telling the
application, strange things can happen. As objects move, ghosts of
those objects can be left behind. If this happens, there is no reason
to panic, as only the screen is wrong. No data has been lost. To
remedy, you simply turn off Screen Cleaning and restart the
application. For this application, Screen Cleaning is not suitable.
Is it useful?
-------------
If you find this program to be useful, you may express your
appreciation by sending $15.00 to:
Scott W. Killen
P.O. Box 27012
Austin Texas 78755
If you have special needs or problems with this program I will be happy
to discuss them. I can be reached at the above address, at CompuServe
ID 76703,734, or by telephone at 1-512-836-1942.
If you contribute, you will receive, by return mail, instructions on
how to disable the monetary request each time the program is installed.