           Galaxian for the TI-86   -   Programmed by Patrick Davidson

                   Version 3.0 (Released September 8, 2000)

----- TABLE OF CONTENTS -----------------------------------------------------

      I. INTRODUCTION                                    17
     II. CLEGAL STUFF                                    42
    III. OPERATING THE GAME                              63
     IV. THE STORY OF GALAXIAN                           81
      V. ENEMY TYPES                                    141
     VI. SCORING                                        206
    VII. CONTACTING THE PROGRAMMER                      219
   VIII. VERSION HISTORY                                231
     IX. THE FUTURE OF GALAXIAN                         337

----- I. INTRODUCTION -------------------------------------------------------

    Galaxian is a small shoot-em-up game for the TI-86 calculator.  In order
to completely take advantage of the calculator's capabilities, it is written
in Z80 assembly language.

    Since Galaxian is an assembly program, it is stored in the calculator as
an executable file rather than text.  Because of this, you cannot easily type
in the program.  You must send it to the calculator to load it.  If you have
a graph-link to connect the calculator to your computer, you can load it by
sending the executable file "GALAXIAN.86P" to your calculator.  If you cannot
connect your calculator to your computer, you must send it to your
calculator from another calculator that already has it.

    Once the program has been copied to your calculator, you can run it by
entering the command "Asm(galaxian" on the home screen.  You can also run it
from a "shell" program if you want to.

    If you want more calculator-related information (such as help on sending
files, buildin a graph-link, or program) or other calculator programs, I
recommend visiting the following web sites.

    http://www.ticalc.org/       ticalc.org
    http://www.calc.org/         Dimension-TI

----- II. LEGAL STUFF -------------------------------------------------------

Since you did not pay me anything for the right to use this software, there
is no warranty of any kind.  This software has been tested, and at the time
of release the author was not aware of any serious problems with it.
However, there is still a possibility of unforeseen problems.  If you do
encounter any problems with this program, please inform me as soon as
possible (of course, I cannot guarantee that I will fix such problems).

This software is in the public domain, which means that it is not copyrighted
at all.  Thus you may use, copy, or modify it any way you want.

However, I would appreciate if you at least do the following if you are
making a modified version:

 - Don't restrict distribution of it
 - Supply source code
 - Give me a reasonable amount of credit
 - Make your version also public domain, or copyrighted under a license that
   still allows users to distibute modified versions freely 

----- III. CONTROLS ---------------------------------------------------------

               TITLE SCREEN CONTROLS

ENTER          Start the game!
F1             Read instructions
EXIT / CLEAR   Leave this wonderful program

               IN-GAME CONTROLS

Arrow keys     Move your ship 
F1             Shoot your main cannon
F2             Shoot lasers (laser energy level appears in upper left corner)
CLEAR          End the current game
EXIT           Exit Galaxian
MORE           Save the game and exit
ENTER or 2ND   Pause the game

----- IV. THE STORY OF GALAXIAN ---------------------------------------------

    An alien civilization knows as the Galaxians developed on the planet
Galaxia, which is approximately 80 light-years away from Earth.  Many years
ago (around 800 C.E. by Earth's calendar), there was great unrest on
Galaxia.  Many citizens of Galaxia were strongly displeased with their
government, inevitably leading to violent rebellion.  Due to its massive
strength, the Galaxian government managed to subdue most of its opponents.

    However, one particulary extreme group of rebels managed to elude the
government forces.  They called themselves the Rutmi-Gani-Salver, which
roughly translates to "The People's Voice Party."  They believed that the
government had to be taken down by whatever means were necessary.  After
several years of bombings and assassinations which accomplished little,
they decided to unleash biological weapons against the capital city of
Galaxia.

    The deadly germs spread far more than they expected, killing more than
95% of the Galaxians within two weeks.  Since there were no resources to
treat the widespread disease, there was no hope for survival.  A few
Galaxians managed to escape by leaving the planet in spacecraft bound for
distant planets.  Since Galaxian technology at that time was not advanced
enough for long-range space travel, most of the craft did not make it.
However, a few of them did.

    The first Galaxian scout ship reached Earth's solar system and entered
orbit around our sun in 1975 C.E.  They managed to learn a great deal
about the inhabitants of Earth from its radio and television broadcasts.
Within 20 years, they had deciphered several Earth languages.

    The first team of Galaxians landed on Earth on February 20, 1998 C.E.,
in the southeastern part of the nation then known as the United States.
Since they wore detailed costumes to make them look exactly like humans
and could speak English, the nativese of Earth couldn't tell any difference
between them and true humans.

    Over the next few years, they gradually gained increasing influence on
Earth.  By the year 2003 C.E., they had established de facto control over
all major countries on Earth.  In 2005 C.E., they united all nations of
Earth under one government which was secretly controlled by the Galaxians.

    Shortly thereafter, several Galaxian ships carrying tens of thousands
of refugees approached the Earth.  Exactly as they had planned, Earth was
under complete control by the time they had arrived.  They now were ready
to land on Earth and enslave its population.

    But it would not be that easy.  Several group formed on Earth to oppose
them.  The majority of Earth people were completely fooled by the Galaxian-
controlled pupper government, and they fought to destroy virtually all of
the resistance.  Most of those who realized what was going on had no power
to do anything to about it.

    You are now the only surviving resistance fighter on Earth.  The year
is now 2008 C.E., and alien invasion is imminent.  You are in control of a
highly advanced prototype spacecraft, armed with sophisticated weapons and
an experimental auto-regeneration system.  You are the only hope to defend
the Earth from alien conquest.  Succeed, and you will guarantee the freedom
of the people of Earth for years to come.  Fail, and you will have turned
over the Earth to alien invasion.  The whole planet is counting on you!

----- V. ENEMY TYPES --------------------------------------------------------

#....#     These drones are probably the first enemies you will encounter 
#....#  in your quest.  Such enemies are not very dangerous since they can
######  only drop conventional bombs and are easily destroyed.  You should
######  be aware that these drones (as well as more advanced ones) may 
.####.  swoop down in attempts ram your ship.  They will occassionally
..##..  accompany fleets of more advanced craft.


#....#     This type of drone is slightly more dangerous than the first.
##..##  Their armament is just as limited as the previous drones, but they
######  possess energy shielding which allows them to withstand substantial
#....#  firepower without being destroyed.
#....#
.#..#.
..##..

#....#     This type of drone uses similar technology to the previous one.
######  The only difference is a new type of engine which generates the same
#....#  amount of power in less space.  Since the craft is smaller and
.#..#.  lighter, less energy needs to be used for propulsion and thus more
..##..  can be used for the energy shields.

#.....#     These are the most advanced drones you will encounter in
##...##  Galaxian.  Due to more advanced shielding, it will often take four
#.#.#.#  shots from your cannon to destroy them.  They are, however, still
#..#..#  completely vulnerable to lasers.
#.....#

##...##     This is a somewhat strange enemy.  The cross ships were meant
###.###  as trainers for beginning pilots.  However, they do carry live
.#####.  bombs on training missions, so they may sometimes be sent to 
..###..  attack you when you approach them.  Since the pilots of these craft
.#####.  are not very experienced, they will fly eratically and sometimes
###.###  the pilots will be frightened and leave the battle.  In order to
##...##  protect the pilots from themselves, they are well armored.

.#####.     These craft are light fighters.  They are manufactured and
#######  piloted by humans, primarily former telephone compnay employees,
##...##  who went to work for the Galaxian military after their former jobs 
##...##  were declared illegal by the Anti-Communications Act of 2006.
##...##  They have rotating cannons which fire directly towars your ship,
#######  and have advanced energy shielding.  They are among the more
.#####.  dangerous enemies you will encounter.

#..............#     These two types of heavy fighters are   ################
##............##  very similar in capabilities.  They are    ###..........###
#.############.#  armed with two cannons which makes them    ###..........###
#......##......#  farily dangerous.  They also carry a lot   ###..........###
#......##......#  of armor.  They also possess optical       ###..........###
.#.....##.....#.  deflectors which make them completely      ####........####
..#....##....#..  invulnerable to lasers.  Fortunately,      ###.#......#.###
...##########...  you will only meet a few of them.          .#...######...#.

   The most dangerous enemy in Galaxian is the ATTACK CRUISER.  These are the
ships which carry the alien invaders down to the Earth's surface.  Because of
this, they are heavily armed and heavily armored.  They typically possess
four cannons, are capable of absorbing more than 90 cannon shots, and are
completely invulnerable to lasers.  In addition to this, these ships are
also capable of manufacturing and deploying drones during combat.  Because
the ATTACK CRUISERS are the backbone of the Galaxian invasion, the Galaxians
will be much more willing to reach a peaceful settlement after you have
destroyed a couple of these.

----- VI. SCORING -----------------------------------------------------------

                                        Each    Total

Hitting a normal enemy                    10     9920
Hitting a boss                            25     5900
Destruction of normal enemy              100    33200
Entering a level                         200     4000
Destruction of boss                     1000     6000
Victory bonus                           5000     5000

Best possible score                             64020

----- VII. CONTACTING THE PROGRAMMER ----------------------------------------

E-Mail:        pad@calc.org
               pad@ocf.berkeley.edu
               luezma@netscape.net
               ariwsi@rocketmail.com

WWW:           http://pad.calc.org/
               http://www.ocf.berkeley.edu/~pad/
               http://www.calweb.com/~kwdavids/patrick/
               http://surf.to/eeulplek/

----- VIII. VERSION HISTORY -------------------------------------------------

 0.1   05-Oct-97  3069 bytes  First functional version

 0.2   06-Oct-97  2848 bytes  Fixed enemy positioning bug
                              You get higher scores
                              Fixed contrast restore bug
                              Optimized enemy code to save 109 bytes

 0.3   06-Oct-97  3068 bytes  Subtracts points when you die
                              Bosses partially implemented

 1.0   07-Oct-97  3556 bytes  Bosses now work
                              Takes away points when enemies swoop
                              Added three new levels

 1.1   08-Oct-97  3699 bytes  Added three new levels
                              Added a new enemy type
                              Optimized collision detection
                              Fixed enemy swooping

 1.2   09-Oct-97  3688 bytes  Fixed enemy swooping (really this time)
                              Optimized enemy code
                              Fixed level error

 1.4   31-Oct-97  3684 bytes  Optimized sprite routine
                              Fixed collisions between you & enemies

 1.5   10-Nov-97  3778 bytes  Laser beam added
                              Fixed contrast bug
                              Save game no longer saves unneeded data
                              Scores slightly higher
                            
 1.6   11-Nov-97  3782 bytes  Small laser beam bug fixed

 1.7   14-Nov-97  3769 bytes  Fixed title screen
                              Optimized level code
                              Optimized enemy code

 2.0a  22-Nov-97  3820 bytes  Fixed save game
                              2nd is now also a pause key
                              Can adjust contrast while paused
                              Built-in highscores a little higher
                              Optimized main loop
                              Made second set of enemies smaller
                              Changed title screen

 2.0b  16-Dec-97  4072 bytes  Bosses now shoot sideways
                              Added two hard "-----" levels
                              Cleaned up collision detection
                              Miscellaneous optimizations

 2.0e  17-Dec-97  4140 bytes  Added three new levels
                              Allowed multiple enemy types on a level
                              Fixed laser bug
                              Miscellaneous optimizations
       
 2.0   18-Dec-97  4079 bytes  Optimized a lot                            
                              Fixed scoring bugs

 2.01  18-Dec-97  4084 bytes  Fixed bug which caused you not to come
                              back after being killed once

 2.02   5-Mar-98  4083 bytes  Fixed the infamous laser bug
                              Enemy code (slightly) optimized

 3.0a  16-Feb-98  4163 bytes  Level system redone
                              Added "cheat key"
                              Scoring redone

 3.0b  17-Feb-98  4151 bytes  Enemy code optimized
                              Enemy images corrected

 3.0c  20-Feb-98  4340 bytes  Cross enemies only appear temporarily
                              Final superboss added
                              Changed score subtract system

 3.0d  23-Feb-98  4346 bytes  Now get 5 lives & 5 lasers
                              Level loading code more robust
                              Fixed levels 14 & 16
                              Removed an unneeded string
                              Fixed score calculation bug

 3.0e  27-Feb-98  4341 bytes  Re-arranged some code
                              Enemy swoop now subtracts point at bottom
                              Final enemy now must be hit 40 times

 3.0f   3-Mar-98  4488 bytes  Added levels 17 and 18
                              "Operator" enemies added
                              Super-bosses now spit out enemies
                              Changed final boss graphics
                              Fixed enemy deployment
                              Fixed laser beam (yes, at last!)

 3.0h   4-Mar-98  4471 bytes  Adjusted enemy deployment positioning
                              Optimized regular enemy code
                              Fixed enemy entry code
                              Inserted two more "operator" levels
                              Scoring changed
                              Now have 9 lives & 9 lasers

 3.0   14-Mar-98  4468 bytes  Only 1/2 of Cross enemies now run away
                              Something else that I don't even remember what

 3.0    8-Sep-00  4535 bytes  Ported to TI-86

----- IX. THE FUTURE OF GALAXIAN --------------------------------------------

There will probably be no more versions of this game, other than to fix any
bugs that might be found in this game.  I don't really want to make any
changes to it, since (except for making this straightforward conversion to
the TI-86) it has not been changed at all for more than 2 years and has
worked fine all that time.

However, I do plan to make several new games for the TI-86, as well as TI-82
and TI-85 calculators.  One of the new games, a TI-85/86 version of Phoenix,
is already available right now in an early version and should be rapidly
developed in the next month or so.  This game is quite similar to Galaxian,
but is much more advanced, and also much larger.  In addition to Phoenix, I
am considering at least three other games for these calculators, as well as
several new projects for TI-89, TI-92, and TI-92+ calculators.
