by J. Michael Ambrosio
To many people, "cool" and "text-mode" are two words that do not belong in the same sentence. After all, text mode was the standard in the Dark Old Days of DOS. Wasn't the whole idea behind GUIs (such as Windows and the Macintosh) to finally rid the computing world of text mode forever? Why celebrate something that is long dead, was never cool to begin with, and that most people hated anyway?
The fact is, text-mode has gotten a bad rap, mostly due to early operating systems like DOS
and UNIX that presented users with a mysterious, dark, nasty-looking command prompt:
The Great and Terrible
DOS Prompt
To this day, the DOS prompt is capable of instilling a unique sense of dread in uninitiated
Mac and Windows users. But it didn't have to be this way. Text mode was in fact capable of a
wide range of graphical effects, as the games in this collection amply demonstrate.
Text-mode games are cool because they managed to take dark, nasty, terrible text-mode and
turn it into something fun, colorful, and playful. These pages are a record of the challenges
programmers had to overcome to make that happen.
I realize that many people whose first exposure to computers was Windows or a Mac have never
even seen text mode. Therefore, I want to begin by explaining what text mode is.
The best way to do that is to compare it to graphic mode, the display standard for most
operating systems in use today.
LET'S BEGIN BY EXPLAINING what graphic mode is. If you are
using Windows, a Macintosh, an iMac, or even WebTV, you are in graphic mode right now. In graphic
mode, every tiny point (pixel) on the computer screen can be individually painted by the programmer. See the
little box underneath this paragraph? Can you see the teeny-tiny black dot at the center? Look
closely:
Did you see it? That was one pixel. Just how many of these are on your computer screen? Well, a typical screen resolution these days is 800 by 600 pixels{1}. At that resolution, there would be 480,000 pixels per screen.
Another aspect of graphic mode is that each and every
pixel can be painted a different color. Take a look at the rectangle below. There are six colored
pixels inside it, from left to right: red, orange, yellow, green, blue and violet. Can you see them?
When you consider that there are tens of thousands of pixels in graphic mode, each of which can be set to hundreds of different colors, you can begin to understand the kind of power and flexibility that programmers have when displaying images on your screen. This is one of the primary reasons why so many programs use graphic mode today (also known as GUI, for Graphical User Interface). GUIs allow developers to represent system commands using pictures (icons) that anyone can understand.
But this is not the whole story. You see, pervasive
use of graphic mode is a relatively new phenomenon in the world of computing. It was first
introduced by the Apple MacIntosh in the mid eighties{2},
and has only been widely in use on PCs since
the release of Windows 3.1 in 1991. Before that, text mode was king.AS ITS NAME IMPLIES, text mode can only display text—that is,
any symbol that can be produced by pressing a key on the keyboard (plus a few extras that we'll
get to in a moment). Text mode cannot be used to paint a picture, draw a pie chart,
or display a scanned photograph.
To put it in technical terms, all the available pixels are divided up into
an 80 x 25 grid{3}
of characters. A character is defined as one of the 255 symbols in the
IBM extended ASCII{4} character set:
As you can see, there is not much to choose from: upper-and- lower case letters, numbers, foreign letters, symbols for line and box drawing, and miscellanous symbols for things like mathematical equations and foreign currency.{5}
So you can see already that text mode is very restrictive, from a visual design standpoint,
compared to graphic mode. First, you are limited to drawing with just 2000 characters, rather than 480,000
pixels. Second, you cannot just design your own characters; rather, you must choose from one of
the 255 symbols provided in the ASCII character set.AS IF THIS WEREN'T LIMITING ENOUGH, there is also the matter of which colors you have to
choose from. In stark contrast to graphic mode, where developers have
a minimum palette of 216 colors{6},
text mode provides only these 16 colors{7} to work with:
Of course, that only adds up to 16 if you consider white, black, and gray to be colors
(and I suspect most people don't—would you be happy with a "color" printer that could only
print grayscales?). Geek Notes
Are you beginning to see why a well-designed, visually appealing text-mode game is such an
achievement? As I look over the games in the collection, I am amazed at how each one manages to
stake out its own unique look and feel, despite the enormous restrictions imposed by the use of
text mode.
Now it's time to take a tour of our collection.
As you look at, read about, and
(hopefully) download and play the games, think about the combination of technical skill and
artistry that went into them. I consider these games to be works of
ASCII art, and I'm proud to have them
on display in our virtual gallery at TextModeGames.com.
1) Some other common screen resolutions are 640 by 480 (standard VGA),
1024 by 768, and 1280 by 1024. If you are using Windows 95/98, you can find out what your screen
resolution is. Click the Start button, then select Settings/Control Panel from the menus.
Double-click the Display icon in Control Panel. Now, click on the Settings tab in the upper
right corner. Your screen resolution is displayed under "Desktop area". You can also find out
how many colors your display supports by looking at "Color palette".
2) Actually, GUI was first developed at Xerox PARC (Palo Alto Research Center) during
the 1970s. Apple took the idea from Xerox (during an infamous visit by Apple co-founder Steve Jobs),
and became the first company to successfully market it as a consumer product.
3) In addition to the standard grid of 80 x 25 characters, text-mode also supports
40 x 25 (used by Insanity), and 80 x 50 (used by
Islands of Danger in VGA mode). That is why the individual
characters appear larger and smaller, respectively, in those two games compared to the average.
4) ASCII stands for American Standard Code for Information Interchange. The acronym
ASCII (pronounced ask'-ee) is virtually synonymous with text-mode, and text-mode games are
commonly referred to as ASCII games. However, I have refrained from calling them ASCII games,
because there is a Japanese software company named ASCII, and I didn't want to cause any confusion.
5) ASCII purists would want you to know that only characters 32 to 126 (! to ~ on the chart)
are standard ASCII drawing characters. The others are part of the IBM extended character set
and are only available on DOS computers. However, since all of the games in this collection
are written for DOS, we will consider the IBM extensions standard for our purposes.
6) The earliest graphic adapter (CGA) had even fewer colors than text mode—only four, to be exact.
CGA was quickly supplanted by EGA (16 colors), and then VGA (256 colors). Most graphic adapters
sold today support millions of colors, but 256-color VGA is still considered the baseline.
So why the number 216? Because the Netscape browser-safe palette has only 216 colors;
the other 40 are reserved for use by the browser.
7) The color names are defined in the standard C header "conio.h".
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Copyright 2002, 1999 J. Michael Ambrosio
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