Transcript 42x60 Horizontal Poster

Investigation into Computer AI, and the Math Behind It.
Joseph Pegues, Advisor: Dr. Christopher Elmer
Shepherd University
http://webpages.shepherd.edu/jpegue01/
Introduction
The purpose behind the project was to examine
computer artificial intelligence and to show that
artificial intelligence could be applied to many
different projects. To do all this, a copy of Quake
2, and a computer AI bot, 3zb2, were acquired.
A bot is a multiplayer opponent who is computer
controlled, but designed to act like a human
opponent.
The hope was that by examining 3zb2 and altering
its code to produce bots with variations, that it
would show that computer AI can perform a
number of different tasks even in a limited
environment. This would imply that by removing
the limiting environment the only limitation of AI
would be the imaginations and coding skills of the
AI creator.
3ZB2
3zb2 was originally created by Ponpoko (internet
name), and was acquired from his website
http://ponpoko.tri6.net/3zb2/. The bot has not had
any development for several years, but was strong
enough to allow for modifications that wouldn't
result in crashes over small changes in the code.
Programming wise the bot has no planning in its
thinking patterns. Instead the bot is reliant on
information that it knows to decide what course of
action is best at the moment. This information is
gathered in two ways. The first is visually by
recognizing what is in front of it. The second is by
recorded route information that is stored in a file
outside of the bot code.
While this type of bot is relatively simple in terms
of computer AI used in video games today, this AI
excels in the simplistic environment of Quake 2. It
is capable of near perfect shooting, always knows
where items are on a map that it has routes for, and
always chooses the best option in a given scenario.
Packrat
The concept of Packrat was a bot that would
horde items before attempting to attack anyone.
Before attempting to enter a combat state the bot
goes through a list of items. If it has enough then
it is allowed to go into that combat state and
ceases item searching.
tem = Fdi_SHELLS;//FindItem("Shells");
if (item)
{
index = ITEM_INDEX(item);
if (ent->client->pers.inventory[index] >= ent->client>pers.max_shells-85)
{
item = Fdi_CELLS;//FindItem("Cells");
if (item)
{
index = ITEM_INDEX(item);
if (ent->client->pers.inventory[index] >= ent->client>pers.max_cells-150)
{
Teleport /
Backwards
Telebort and Backwards are two bots born from
opposite logic patterns. When taking into account
things like shooting and moving to objects, the bot
makes calculations based off its movement speed.
For teleport this speed has been multiplied by 10,
and for backwards negative one.
Interestingly, Teleport exhibits an almost chaotic
behavior because it can never get to where it wants
to be properly. This chaotic behavior seems to
stabilize as more bots are added to the game.
Guardbot is a bot with a job to do. It is given a
specific item in the game to hunt out, and once it is
found the bot stays within short distance of it. It's
objective is to prevent anyone from getting the
item.
if(foundRocket != 1) Bot_SearchItems(ent);
if(zc->second_target != NULL )
{
if((zc->second_target->s.origin[2] - ent->s.origin[2]) > 32
&& !ent->waterlevel)
{
RL = zc->second_target->moveinfo.start_origin[2]-ent>s.origin[2];
if(foundRocket==1&&(RL <= lh || RL >= hh)
{
VectorAdd(zc->second_target->moveinfo.start_origin,ent>s.origin,temppos);
}
Conclusion
Santabot
Santabot is a bot that was designed as a
noncombatant. Commands dealing with firing at
opponents have been removed and replaced with
drop item commands. Thereby giving other
combatants items that the bot is holding onto.
Guardbot
EnemiesAbound
/GhostsAbound
EnemiesAbound and GhostsAbound are also
created from opposite logic patterns.
EnemiesAbound believes itself to be constantly
confronted by enemies and so is constantly ready to
attack an opponent. GhostsAbound is a bot that
never believes itself to confronted by an enemy so
never fires its weapon.
Interestingly, EnemiesAbound is slightly smarter
than 3zb2, and at times, even acts more like a
human opponent as opposed to a computer
controlled bot.
In this project several different logic patterns for
the bots were created. Even in the limited
environment of Quake 2 it is possible to create
AIs that do more than simply shoot at an
opponent. However the bots we're not only
limited by the environment in this project, they
were also limited by 3zb2. With more time and a
better understanding of how Quake 2 works, it
would be possible to create even more bots,
possibly even some with the ability to plan.
Bibliography
1.Quake 2 was developed by id Software and
the game box artwork belongs to them.
www.idsoftware.com
2.3zb2 was created and owned by Ponoko. It
and the code behind it are owned by him.
http://ponpoko.tri6.net/3zb2/
3.This poster template was created by
MegaPrint, and downloaded from:
http://www.postersession.com/templates.php