Racing the Beam : the Atari Video Computer System - Index of

why the cursor matches the walls and why its color changes from screen
to screen.
To create the “light” that emanates from the player, Adventure uses a
widened square sprite that is orange. The player is centered inside this
“box,” and both are moved together. The same TIA register that controls
playfi eld refl ection or mirroring can also be set to draw the playfi eld
either underneath the sprite (the default setting) or on top of it (as in
Combat’s plane variants). In the catacombs, the playfi eld is set to draw
on top of the sprite, making the area around the player cursor appear to
glow with light. The effect is sophisticated, but it is implemented in a
straightforward way. The circle of light is just another carried object, no
different from a sword or a key. A similar implementation of partial darkness—although
one that is more advanced—can be seen in Atari’s 1982
VCS game Haunted House.
Some video games implement the fog of war as a way to hide knowledge
that the player can discover. In Civilization, once a player has
explored a part of the world’s terrain, that square always remains visible,
as if the society had entered it into an almanac. Other games implement
the fog of war as transitory knowledge. In Warcraft, a player must have
units in a region to be able to see its immediate surroundings. Both of
these methods have their origins in Adventure’s implementation of the
fog of war.
The Easter Egg
An Easter egg is a message, trick, or unusual behavior hidden inside a
computer program by its creator. Easter eggs can be traced back at least
to the early 1970s, when the TOPS-10 operating system on the PDP-10
was programmed to respond to the command “make love” with “not
war?” 12 More recent Easter eggs are much more sophisticated. One recent
version of Microsoft Excel contains a hidden fl ight simulator game, as does
Google Earth.
Adventure contained the fi rst Easter egg known to appear in any video
game. The hidden message itself is reasonably simple. Warren Robinett
signed his game “Created by Warren Robinett” using letters running vertically
down the center of the screen (see fi gure 3.4). Accessing the Easter
egg is less simple. To fi nd it, the player must cross a sealed wall in the
black castle using the bridge and then pick up a single black “dot” (actually
a sprite graphic), which must be brought to another wall in the yellow
castle. The dot grants the avatar entry into the secret room.
3 Adventure [59]