README for xsoldier
$Id: README,v 1.9 2011/08/09 08:12:25 oohara Exp $

* what is xsoldier
xsoldier is a shoot 'em up game with the "not shooting" bonus.  It is
2D (that is, hardware acceleration is not necessary if you have a "not bad"
CPU) game for one player using the X Window System or the Simple DirectMedia
Layer (SDL) library.

So, why yet another shoot 'em up?  Because xsoldier has a unique feature
--- the "not shooting" bonus.  You can get a pretty good score by not
pressing the shoot button.  This is an answer to my motto for a shoot 'em up,
that is, "why a shoot button?".  After all, if the game is a simple
kill-everything and shooting is always a good thing, why do I have to
press a shoot button (or worse, hit the shoot button again and again)?
You can play xsoldier as a simple kill-everything (and it is the best way
to survive), but if you care your score, you need to kill all enemies
with a minimum number of bullets.

* how to install xsoldier
See the file INSTALL for information about how to install xsoldier.
In short, install libc, libX11 and libXpm, then type
1) ./configure
2) make
3) make install
If you use SDL instead of X, install libSDL and libSDL_image instead of
libX11 and libXpm, then use the --with-sdl option of ./configure .

* overview of the game
In xsoldier, you move a space ship and shoot enemies (they usually appear
from the upper side of the window, but some appear from the _lower_ side).
If you kill the boss enemy which appears at the end of each stage, or if
you can survive till the boss enemy gets bored with you and escapes, you
can go to the next stage.

xsoldier has 8 stages.  You need to clear each stage 3 times to clear the
entire game (24 stages total).  A set of the 8 stages is called a "loop".
If you cleared the first loop (that is, the first 8 stages), the second
loop will begin after the ending (a staff scroll), with more difficulty
(enemies shoot more, enemy shots move faster and so on).  Similarly,
the third loop will begin after the second loop (and the second ending).
The third loop is very dangerous because enemies will _always_ leave a shot
when they die.

* command line options

** (-d | -display) NAME
Specify the (X window) display on which you want to play the game.

** (-w | -wait) NUMBER
Set the speed of the game.  A higher number means the game runs slower.
NUMBER must be a positive integer.  If you use this option and if NUMBER
is greater than the default (use -h to see it), the ranking mode is
turned off.

** (-c | -cmap)
This option has no effect (only for backward compatibility).

** (-s | -score)
Show the top 10 soldiers, that is, the high score list.

** (-h | -help)
Show a short help text and exit.

** -maxlevel
Force max level enemy attack, making your life really harder.

** -nopausemessage
Don't show "Press [p] to resume game." message when the game is paused.
This is useful for capturing a screen snapshot.


If you compiled xsoldier with debugging features, the follwing options
are also available.  They disable the ranking mode.

** -stage L-S
Start the game with the stage S of the loop L.  S must be a positive
integer between 1 and 8, and L must be a positive integer between
1 and 3.

** -stage S
Start the game with the stage S.  S must be a positive integer between
1 and 8,

** -loop L
Start the game with the loop L.  L must be a positive integer between
1 and 3.

** -ship N
Start the game with N ships.  N must be a integer between 0 and 99.

** -maxpower
Make sure that you always have a maximum power weapon.

* key control
cursor keys        move
left shift         shoot (auto-repeat)
a                  speed up
s                  speed down
p                  pause/resume
q                  quit the game
space              start the game (in the title/ending)

You can use a joystick too if xsoldier is compiled with joystick support
(see INSTALL).  Note that joystick support is no longer maintained.
Probably it won't work on a system other than Linux.

If you compiled xsoldier with debug features, some keys are also available
for cheating:
w                  change weapon
c                  clear enemy shots

* power-up items
Some enemies sometimes leave a power-up item when they die (others never do).
There are 2 kinds of items.  The one which says "Pow" makes your shots more
powerful.  The other one (which changes its appearance periodically) changes
your weapon and makes your shots a bit more powerful.

There are 3 kinds of weapons you can use --- blue, yellow and gray.
The blue shot is fast, damages fairly well and you can shoot it
backward if you correct enough power-up items.  The yellow shot shoots
many, many bullets, so you don't need to aim very carefully.  However,
each bullet deals only a little damage.  The gray shot is slow and
you can shoot it only forward, but it damages very well (even boss enemies
will die in a few seconds).

If you already have enough power-up items and gets another one, it will
give you bonus points.  If you die, you may lose some of power-up items.

* "not shooting" bonus
You get a bonus automatically as long as you don't press the shoot key
(to be precise, if it is at least 5 frames after you released the shoot key).
This bonus is called "not shooting" bonus.  The more enemy there are in
the window, the more points you get.  Enemy shots, power-up items and
explosions also count as enemies for the "not shooting" bonus.

* shoot down bonus
When you clear a stage by destroying the boss enemy, you get a bonus
according to the percentage of enemies you destroyed in this stage.
95% destroy bonus is 1/2 of 100% destroy bonus, 90% destroy bonus is
1/3 of of 100% destroy bonus and so on.  The shoot down bonus is larger
in later stages.

* game tips
Your ship is smaller than it looks.  In other words, your ship will not be
destroyed even if enemy shots touch it a bit.

The yellow shot is the best way to survive.  Keep pressing the shoot key
unless you are an expert.  Problems are that your score will be poor and
that the yellow shot is not good at killing the boss enemies.

Play with the boss enemies for a while to get the "not shooting" bonus.
stage   estimated bonus    difficulty
  1       small              easy
  2       small              very easy (loop 1), hard (loop 2 or later)
  3       small              hard
  4       medium             normal (loop 1 or 2), hard (loop 3)
  5       very big           easy (loop 1), normal (loop 2 or later)
  6       big                hard
  7       small              hard
  8       very big           very hard
Make sure that you destroy the boss enemies before they escape.  Don't
miss the shoot down bonus.

* feedback
Send comments or bug reports to Oohara Yuuma <oohara@libra.interq.or.jp>.
Also check the xsoldier webpage:
http://www.interq.or.jp/libra/oohara/xsoldier/index.html

* license
See the file LICENSE for information about the license.  In short,
the license is GPL version 2 or later.

* history
The original author of xsoldier was Yuusuke HASHIMOTO <hachi@pm.highway.ne.jp>.
He maintained xsoldier until version 0.96.  It was a simple but decent
shoot 'em up.  The original xsoldier webpage was
http://www.surfline.ne.jp/hachi/xsoldier.html .

Oohara Yuuma <oohara@libra.interq.or.jp> took over the development of
xsoldier and added the "not shooting" bonus.  The game bacame easy if
you are interested in just surviving.