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Liquid War(6)			 Games Manual			 Liquid	War(6)

NAME
       liquidwar - a unique multiplayer	wargame

SYNOPSIS
       liquidwar [-vh]

DESCRIPTION
       Liquid  War is a	multiplayer wargame. Its rules are very	simple but yet
       original.

OPTIONS
       -v Displays the version number.

       -h Displays copyright and various information.

       ...
	  There	are many other command lines options, which are	described fur-
	  ther in this document.

WARNING
       As Liquid War is	a cross-platform program (it also runs on DOS and Win-
       dows), I	could reasonably not provide groff UNIX-style documentation to
       Windows	user.  Therefore,  Liquid  War's documentation is available in
       many formats, including HTML, PostScript	and PDF.
       I believe these formats are easier to read  than	 this  man  page.   So
       check  out the /usr/share/doc/liquidwar or /usr/local/share/doc/liquid-
       war directories,	for this is where HTML and other  documentation	 files
       should be. Otherwise, if	you are	a die-hard man page user, you may con-
       tinue with this document	8-)

Rules
   The Liquid War concept
       Liquid War is a wargame.	But it is different from common	wargames.

       When playing Liquid War,	one has	to eat one's opponent.	There  can  be
       from  2	to 6 players. There are	no weapons, the	only thing you have to
       do is to	move a cursor in a 2-D battlefield. This cursor	is followed by
       your  army, which is composed by	a great	many little fighters. Fighters
       are represented by small	colored	squares. All the fighters who have the
       same  color  belong  to	the same team. One very	often controls several
       thousands fighters at the same time. And	when fighters  from  different
       teams meet, they	eat each other,	it is as simple	as that.

   How do teams	react?
       Teams  are composed of little fighters. These fighters all act indepen-
       dently, so it can happen	that one single	fighters does  something  dif-
       ferent from what	all the	other do.

       The main	goal of	these fighters is to reach the cursor you control. And
       to do that, they	are in a way quite clever, for they choose the	short-
       est  way	 to  reach  it.	 Check	it  if	you want, but it is true, they
       *really*	choose *the* shortest way to reach the	cursor.	 That  is  the
       whole point with	Liquid War.

       But  these  fighters are	not perfect, so	when they choose this shortest
       way, they do as if they were alone on the battlefield.  That's  to  say
       that if there is	a fighter blocking their way, they won't have the idea
       to choose another way, which is free from fighters but would have  been
       longer otherwise. So fighters can be blocked.

   Who eats whom?
       When  two  fighters from	different team meet each other,	they first try
       to avoid	fighting, and they dodge. But if there is no way for  them  to
       move,  they  get	angry and attack the guy which is blocking them. Some-
       times, they attack each other and both loose health. But	it can	happen
       that  a	fighter	 is  attacked  by  another  one,  which	is himself not
       attacked	at all.

       Here is an example of this behaviour: A blue fighter and	a red  fighter
       both want to move to their right, for that would	be the shortest	way to
       reach their cursor if there was nobody on the battlefield. But they are
       blocked	by other fighters. If, for instance, the red fighter is	on the
       right and the blue fighter on the left, it is  the  red	fighter	 which
       will be eaten.

       When a fighter is attacked, he first looses health, that	is to say that
       he gets darker. When his	health reaches 0, his  color  changes  and  he
       becomes	a  member of the team by which he has been attacked. Therefore
       the number of fighters on the battlefield always	remains	the same.

       When fighters of	a same team get	stuck together and block  each	other,
       then they regenerate, that is to	say that they get brighter.

       However,	I think	the best way for you to	understand the way it works is
       to try the game...

   Basic strategy
       When I play Liquid War, I always	try to surround	my opponents,  and  it
       usually works.

       By  the	way, the computer has no strategy at all, he is	a poor player,
       and if you get beaten by	him, it	means you have to improve  yourself  a
       lot!

       But  still,  the	 computer  doesn't  do	one thing which	I've seen many
       beginners doing:	he never keeps his cursor motionless right in the mid-
       dle of his own fighters,	for this is the	best way to loose.

   More	strategy
       Here are	some more tips,	kindly submitted by Jan	Samohyl.

       *  Try  to cut your opponent off	walls and surround him completely with
	  your troops; when trying to penetrate	his forces  inside  a  tunnel,
	  keep	your  troops at	the wall (and force them ocassionaly to	attack
	  off the wall). I think this is a biggest weakness  of	 the  computer
	  AI, that it doesn't know this.

       *  When	luring your troops to outflank an enemy, always	move your cur-
	  sor through the enemy, not the other way around.

       *  To penetrate very narrow tunnels, stand back for  a  while  and  let
	  some	enemy  troops come from	the tunnel to you. Then	surround them,
	  destroy, repeat.

       *  I have observed that with more than 2	players	(6), the  game	diffi-
	  culty	 depends on the	map in the following way: If the playing field
	  is completely	empty, without any holes (topologically	equivalent  to
	  full	circle),  the  game  is	 the  easiest, because you can just go
	  through the middle to	outflank your opponent.	If there is  a	single
	  large	 obstacle  (ie.	 playfield is topologically equivalent to ring
	  (the area between two	nested circles)), the game is the most	diffi-
	  cult,	 because  you have to choose one direction for the attack, and
	  cannot simply	defend the other direction. For	other maps,  it	 seems
	  to  really  depend  on  their	similarity to one of these two extreme
	  situations (and army size, of	course,	because	it changes  the	 rela-
	  tive	size  of obstacles). Also, if you would	later add another cur-
	  sor, this property would probably disappear (maybe then  games  with
	  n+1 obstacles	would be the hardest ones with n cursors).

       *  If  you  want	a particularly challenging computer game (at least for
	  some maps), use several players, max out attack,  min	 out  defense,
	  max out base health (opposite	would be harder, but game then changes
	  to the large cloud of	black troops, so you don't see	anything)  and
	  give winner an advantage.

   The winner is...
       The  clever guy who has got the greatest	number of fighters in his team
       at the end of the game. Or the  one  who	 exterminates  all  the	 other
       teams!

Authors
   Thom-Thom
       Liquid War rules	have been invented by Thomas Colcombet.

       He  was	trying	to  find algorithms to find the	shortest path from one
       point to	another, and found the Liquid War algorithm. Then it  came  to
       his mind	that a game could be build upon	this algorithm,	and Liquid War
       was born. He programmed the first two versions of Liquid	War using Bor-
       land  Pascal  for DOS, and gave me some information about the algorithm
       so that I could re-program it.

   U-Foot
       I'm the guy who	programmed  the	 latest	 versions  of  Liquid  War.  I
       enhanced	the algorithms,	and did	quite a	bunch of work to have the game
       playable	by (almost) anyone, that's to say create a correct GUI.

       If you want to join me, here's all the information you'll ever need:

       Christian Mauduit

       E-mail: ufoot@ufoot.org
       Web site: http://www.ufoot.org

       GnuPG public key: FD409E94 - http://www.ufoot.org/gnupg.pub
       GnuPG fingerprint: 4762 1EBA 5FA3 E62F 299C  B0BB DE3F 2BCD FD40	9E94

       Snail mail: 32 rue Jean Moulin  95100 Argenteuil	 FRANCE

   Other contributors
       As Liquid War is	now free software, protected by	 the  GPL,  anyone  is
       allowed to view,	edit, modify, re-compile the source code, and distrib-
       ute it, as long as Liquid War is	still distributed under	the GPL.

       Here's a	list of	the contributors:

       *  Alstar: drew a map, which is now included in the main	distribution.

       *  Peter	Wang: ported Liquid War	to GNU/Linux.

       *  Cort Danger Stratton : helped	me setting up network support.

       *  Tim Chadburn : wrote midi files for the game.	His  contribution  has
	  been	truely appreciated since it's rather hard to find GNU GPL com-
	  pliant artwork. He also wrote	documentation  and  helped  with  midi
	  support in general.

       *  Jan Gretschuskin : contributed 11 maps, and made the German transla-
	  tion.	So if you run Liquid War with German menus, you	know  who  you
	  have	 to   thank   ->   Jan!	 8-)  Also  do	not  forget  to	 visit
	  http://www.game-factor.de

       *  Mouse	: contributed a	map.

       *  Rene Stach : drew 3 maps.

       *  Roderick Schertler : implemented HTTP	1.1 support.

       *  Ryan D. Brown	: ported Liquid	War to Mac OS X.

       *  Eduard Bloch : maintained the	Debian package,	and helped with	German
	  support.

       *  Michael Terry	: provided a .desktop file for better integration with
	  Gnome, KDE and other UNIX desktop environments.

       *  Kasper Hviid : contributed many maps,	with their own	textures,  and
	  made	 the   Danish  translation.  Great  work,  also	 available  on
	  http://levels.2v1.cz/index.html

       *  David	Redick : wrote an external random map generator, available  on
	  http://xdavidx.sqrville.org/lwmapgen/index.html

       *  Alexandre Pineau : maintains the Debian package.

       *  Michael Wagner : translated the web site in German.

       *  Peter	Williams : fixed the "too many opened socket" server bug.

       *  Jan Samohyl :	submitted strategy tips.

       *  Gavin	: wrote	the Liquid War fanfic.

       *  Dave Vasilevsky : fixed the Mac OS X port.

       *  2 of omega : contributed a map.

       *  666-REFIZUL-666 : created many maps (distributed separately).

       *  Thomas Klausner : fixed Makefile for FreeBSD

       *  Joan Dolc : helped with Mac OS/X port

       Many  other people helped me by submitting bug reports and patches, and
       I want to thank them for	their precious help. Thanks to all the	Debian
       people too, who nicely maintain the Liquid War .deb package.

Mailing	lists
   liquidwar-user
       Description

       This  list  is  for  general discussions	about Liquid War. Here you can
       make suggestions, submit	bug  reports,  ask  for	 help,	find  players,
       etc...  Basically,  any	question  or remark which concerns the game is
       welcomed	on this	list.

       Practical informations

       You can't send messages to the list without subscribing.	The only  rea-
       son  for	 this  is  that	 it's  one of the only way to block spam effi-
       ciently.	I first	thought	it could be OK to allow	anyone	to  post,  but
       liquidwar-user  seems  to have be harvested by robots, so now I need to
       restrict	posters. However, I insist on the fact that  anyone  can  sub-
       scribe,	and  the  subscription to the list is not moderated. So	if you
       are a human being and not a stupid spam robot, you're  welcome  on  the
       list 8-)

       Here's a	list of	usefull	URLs:

       *  To   (un)subscribe:  http://mail.nongnu.org/mailman/listinfo/liquid-
	  war-user

       *  To   consult	 archives:    http://mail.nongnu.org/pipermail/liquid-
	  war-user/

       *  To post on the list: liquidwar-user@nongnu.org

   Chat	and IRC
       Web-based chat-box

       I  have	have  set  up  a  web-based chat-box which is accessible here:
       http://www.ufoot.org/liquidwar/v5/metaserver.php3

       It's not	as good	as a good old IRC channel but not  everybody  can  use
       IRC (because of firewalls and the likes), and I like the	idea that peo-
       ple can chat and	have the list of available servers in one  single  web
       page.

       IRC channels

       I  personnally  spend some time on irc.freenode.net so you might	use it
       to find other players - though I'm not really an	IRC  addict...	...not
       yet at least!

       Here are	the channels I recommend:

       *  #liquidwar  :	Liquid War dedicated channel, to find players and chat
	  while	playing.

       *  #netgame_players : general channel for  players  who	want  to  play
	  Internet  games  - Free Software and/or Open Source games of course,
	  we're	on freenode.net	8-)

Fanfic
   What's this?
       Quoting Gavin: "I wrote a liquid	war fanfic some	time ago [...] I wrote
       it  after  a  friend  claimed  that  there wasn't any liquid war	fanfic
       because it wasn't possible."

       So here it is, a	Liquid War  fanfic,  enjoy!  (and  special  thanks  to
       Gavin)

   The Battle of Emberlificoted
       ...

       The  General presided over his massing army in his seat,	or rather hov-
       ering ring, of power. It	dipped slightly	as he flew low over his	troops
       marching	 through  the viscous marsh-like terrain. They were like chil-
       dren: obedient, loyal, and they ate a lot.

       Glancing	at the status panel mounted in front of	him he	grimaced;  the
       other  five  armies:  Yellow, Green, Orange, Turquoise, and, of course,
       Red, were also readying armies of a similar size	to his own. His	violet
       clones would have to fight hard and eat well to win this	day.

       Today  would  not be a battle of	luck, the General mused, it would be a
       battle of tactics, of alliances,	and of betrayal. Every clone was iden-
       tical  -	 that  was  the	 general  idea behind clones - and the terrain
       seemed strangely	symmetrical; it	would not give advantage to any	of the
       six  armies  amassed today. Glancing at the hologram of the battlefield
       projected in front of him the General noted that	he would have to  move
       quickly,	 Orange	 and  Yellow were too close for	comfort, though	fortu-
       nately Baron Red's army of eponymous coloured clones was	the furthest.

       General Violet's	fingertips were	sweaty even before  they  touched  the
       four  main  control  keys  in front of him. They	were labeled 'W', 'A',
       'D', and, of course, the	full retreat button - very useful for mislead-
       ing  foes  and  ambushing  them	as  they  pursued - 'S'. The keys were
       arrange in a roughly equilateral	triangular pattern; with  'S'  forming
       the  base and being adjacent to both 'A'	and 'D', 'W' formed the	tip of
       the triangle.

       A long breath left his parched lips as at last he made his move.

       ...

       "Dammit!" he screamed moments later. He had  misjudged  Captain	Yellow
       and  Commander  Orange;	he had expected	one at least to	attack immedi-
       ately, one he could have	handled. They were working together -  foiling
       his attempt to shoot between them to near the center of the battlefield
       to gain a better	vantage	point. Yellow had shot down towards him,  cut-
       ting off	his advance, and now Orange had	sealed his escape route. "It's
       not over	yet" muttered the General. He opened a voice channel with Com-
       mander Orange:

       "Very clever. Flawed, but still clever."

       "Flawed?" came the reply.

       "Yes flawed, when the good Captain is finished devouring	my army	who do
       you think he will turn to next?",  bluffed  the	General	 -  his	 hands
       worked quickly as he manoeuvred his hovering control ring, all that his
       troops ever saw of him, carefully towards the weakest  section  of  his
       attackers.  If  he  could just break out	a few units he could soon turn
       the tide	against	both Yellow and	Orange.

       "We have	an alliance..."	Orange's voice was unsure now.

       Time for	some sarcasm to	through	her even more off balance, thought the
       General,

       "I  gathered", he spoke softly, slowly, and with	too much meaning. Then
       closing the channel he turned his attention back	to his escape.

       ...

       "Yes!" wooped the ecstatic figure of the	General. Fifty or  so  of  his
       troops  had  broken free	undetected and were even now working their way
       cautiously towards the camps of the Yellow army,	only the  front	 lines
       were  still actively fighting; this opening gambit of Yellow and	Orange
       had turned into a stale siege and Yellow's army had pitched tent.

       General Violet steered his hovering guidance ring to the	center of  the
       Yellow camp. His	troops struck, both those who had got behind the lines
       and those who were still	besieged. Yellow reacted too slowly  and  sud-
       denly found that	her army, was shrinking	back from the onslaught. There
       was nowhere to run to, and bye now her only ally	- Commander  Orange  -
       had abandoned her to her	fate; he was too busy engaging Sir. Turquoise,
       who had managed to escape from the slaughter that the Baron had	caused
       to  the Turquoise ranks and was even now	valiantly attacking the	flanks
       of the Orange troops.

       A glance	at the status panel showed that	Yellow's life force was	fading
       quickly:	8%, 3%,	1%, Gone.

       The  General  smiled,  he always	enjoyed	getting	the first kill,	and by
       now his armies life force had grown and his clones had replicated. With
       his,  now,  formidable  fighting	force it was no	problem	to engulf both
       Sir. Turquoise and Commander Orange's brawling  armies  and  annihilate
       them. Once again	his army grew in size and power. Now if	only the Baron
       didn't notice that..., thought the General.

       ...

       "Too late!" yelped the General, now thrown into panic, as  he  saw  the
       approaching  Baron.  His	army had also grown in size and	power -	having
       fatally injured the Turquoise army within the opening  moments  of  the
       battle,	and  having  finally managed to	catch the elusive fleeing form
       of, or what remained of,	Emperor	Green.

       Gripping	the controls harder the	 General  thought  quickly,  his  army
       doesn't	so  completely outnumber me that this is already over, however
       unless I	can cause him to make a	mistake	that allows  me	 to  take  the
       upper hand then I will inevitably lose. Maybe I can...

       This  thought  was  terminated  and  replaced by	another	as the Baron's
       angry red troops	broke through the undergrowth that had	covered	 their
       movements  and started to surround the General's	army. The thought that
       now throbbed through the	panic-stricken mind of General Violet was sim-
       ply 'Run!'.

       Even as he signaled the retreat and made	for what seemed	to be the only
       possible	means of escape	the Baron's blood red control ring appeared at
       the  opening. The General knew it was over, even	before the host	of red
       beings appeared at the opening.

       There was no escape. His	life force was almost depleted and he was sur-
       rounded.	Then it	was that the Baron decided to communicate:

       "Too bad. It was	a good game"

       The  General  blinked, gaped, and was generally gobsmacked. Just	before
       his life	force completely failed	and  his  own  weary  eyes  closed  in
       defeat he snarled,

       "What!? This is not a game!" were the General's dying words.

Menus and hot keys
   Introduction
       This  section  describes	 how the GUI works. Since programming advanced
       GUIs with Allegro is not	so easy	- standard  C  programming  definitely
       lacks flexibility -, and	also since it's	somewhat hard for me to	figure
       out what	is user-friendly and what's not, Liquid	War's  menus  are  not
       always  self-explanatory.  I'll	just  try and do something better next
       time!

   Menus
       Map menu

       The map menu allows you to choose the map you are going to play	on.  A
       map is defined by 3 things:

       *  A  frame. The	frame can be chosen with the slider which is below the
	  preview. The frames are automatically	sorted by alphabetical order.

       *  A texture for	walls.

       *  A texture for	the zone where fighters	are allowed to move.

       In the middle of	the screen, there is a preview of the level.  In  this
       menu, the values	of the parameters can be independently changed by:

       *  Moving a slider.

       *  Clicking on a	"+" or a "-" button.

       *  Typing a number.

       On  each	 side of the preview, sliders allow you	to choose the two tex-
       tures. There is also a preview of  each	texture.  Below	 this  preview
       there  are  128 little buttons which allow you to choose	single colored
       textures.

       The name	of the map and its resolution are displayed in the lower  part
       of the screen.

       You'll notice that on some maps the texture selection zones simply dis-
       appear. This is because these maps are associated with  a  texture,  so
       choosing	a different texture is often not recommended for it won't look
       as nice as with the right one. If you still want	to override  this  be-
       haviour	you  can  click	 on the	"on/off" button	just right to the "Use
       default texture"	label. This is a toggle	button which will allow	you to
       use  your  own  textures	even on	maps that normally come	with their own
       skin.

       You'll also notice that a "Random map" button is	available. This	button
       generates  a  new  random  map  using  an external program, "lwmapgen",
       developped  by	David	Redick,	  available   on   http://www.cs.clem-
       son.edu/~dredick/lwmapgen/

       This program supports many command line options,	and if you want	a very
       precise control on the generated	maps, you'll  need  to	run  it	 sepa-
       rately. Looking at LW's log file	you should be able to see the commands
       LW issues when calling this program, this can give you ideas on how  to
       launch  it  manually.  Alternatively  using  the	 "--help"  option (for
       instance	"liquidwar-mapgen --help" under	UNIX) should describe  how  to
       use it.

       Teams menu

       This menu allows	you to choose the teams	which are going	to play. There
       are 6 square zones in this menu.	Each of	them is	associated to a	team.

       Each team can be	either:

       *  Disabled ("Off")

       *  Controlled by	a player ("Human")

       *  Controlled by	the computer ("Cpu")

       The computer plays poorly, so remember that Liquid War is  basically  a
       multiplayer  game,  and	that the cpu control is	dedicated to beginners
       only.

       You can also choose the color associated	to each	team  by  clicking  on
       one of the 12 colored buttons.

       Below the 12 colored buttons, there are four buttons which allow	you to
       choose your keys. Click on one of these buttons and then	press the  key
       you  want  to  define. Joystick movements and buttons are considered as
       keys. You can disable the joystick with the button which	is at the bot-
       tom left	of the menu. Mouse input is also possible, and mouse movements
       are considered as keys too. To define mouse control, click on the  but-
       ton  associated to the direction	you want to control, and then move the
       mouse. Then the button should display something like "M->". Mouse  sen-
       sibility	 can  be set with the little slider at the bottom right	of the
       menu.

       Graphics	menu

       Here you	can choose the graphic options of the game.

       The "Video mode"	button allows you to  switch  between  fullscreen  and
       windowed	mode. This button is not available under DOS.

       The "Brightness"	slider allows you to set the brightness	of the game.

       The  "Menu  res"	 slider	 allows	 you to	set the	resolution used	by the
       menus. There are	currently 5 possible values,  which  depend  on	 which
       platform	you're running the game	on.

       I personnaly think the menus look best with the 640x480 resolution, but
       some may	prefer higher resolutions. Lower resolutions  should  only  be
       used if you have	problems using SVGA video modes.

       The  "Game res" slider allows you to set	the resolution used during the
       game. The allowed values	are the	same than those	for the	menus. I  rec-
       ommend  that  you  don't	use resolution higher than 640x480, unless you
       have a Pentium VIII running a 10GHz.

       Page flipping can be toggled. It	is up to you to	decide wether you keep
       this  option  or	not. The main disavantage of turning page flipping off
       is that the info	bar and	the battlefield	can look rahter	ugly  if  they
       overlap.	But if you turn	page flipping on you will not easily reach the
       166 frames per second I sometimes get on	small levels with my K6-225. I
       personnaly always turn page flipping off.

       The  viewport  size defines how much of your screen will	be used	by the
       battlefield.

       *  If you set the slider	on its left position, the batllefield will not
	  be  stectched	at all.	Or if is strechted, it will be by a x2 or a x4
	  factor. So this is the mode wich allows the fastest display.

       *  If you set the slider	ont its	right position,	the game will  run  in
	  fullscreen mode.

       *  With	all  the  other	 positions of the slider, the battlefield will
	  keep its general proportions but it will be stretched.

       The "Waves" button allows you to	toggle the wave	effect.	You  can  also
       do this while playing, by simply	pressing F4.

       Sound menu

       This  section allows you	to set the sound volumes. There	are 4 sliders,
       which are:

       *  "Sfx": sets the volume of all	 the  sfx  sounds,  thats  to  say'the
	  sounds you hear when the game	starts,	when you loose etc...

       *  "Click":  sets  the  volume  of the click, this nasty	noise you hear
	  each time your press on a button.

       *  "Game	water":	sets the volume	of the blop blop blop sounds which are
	  played continuously while you	are playing.

       *  "Menu	 water":  the same thing than "Game water" except that it con-
	  cerns	the sounds played while	your are choosing options.

       *  "Music": general music volume.

       Rules menu

       This menu is the	one where you can change the rules of the game.

       The "Time" slider controls the time limit. The  game  will  stop	 after
       this time is elapsed. You can pause the game by pressing	the "F3" key.

       By  the	way, an	info bar can display the time left while you are play-
       ing. This info bar can be toggled during	the game by pressing the  "F1"
       key,  and you can change	its location by	pressing the "F2" key. It also
       displays	how many fighters there	are in each team.

       The "Army size" slider controls the amount of fighters there will be on
       the  battlefield.  The  position	 of  the slider	reflects the amount of
       fighters	of all the teams together. If there are	 4  teams,  then  each
       player  will  have  half	as many	fighters than if there had only	been 2
       teams.

       The "Cursor x" slider controls the speed	of your	cursor.

       *  If it	is set on the left, the	cursor goes at the same	speed than the
	  fighters.

       *  If it	is centered, the cursor	goes twice faster than the fighters.

       *  If  it is set	on the right, the speed	of the cursor is multiplicated
	  by 3.

       Below is	a "Min 160x100"	box with a slider on  its  right.  This	 means
       that  maps  will	automatically be magnified so that they	have a size of
       at least	160x100. Indeed, some of the maps that come  with  Liquid  War
       were  designed  in 1995 when 486	Intel computers	were common. Therefore
       the maps	were smalls. Today, these maps are not really fun to  play  on
       fast  computers,	 so  Thomas  Harte suggested this automatic magnifying
       feature,	and that was IMHO a smart idea.	You can	move the slider	to the
       right to	make maps use a	higher resolution - ie magnify them.

       The  "Defaults"	button	of  the	"Rules"	menu will reset	rules to their
       defaults. This way you can tweak	 rules	and  then  come	 back  to  the
       default	rules  whenever	 you want. Note	that there's also a "Defaults"
       button in the main "Options" menu, but it  will	reset  *all*  options,
       including player	names... The advantage of the "Defaults" button	in the
       "Rules" menu is that it will only reset rules parameters, and keep  the
       rest of your configuration options untouched.

       Speeds menu

       The "frames/s" slider allows you	to limit the number of frames per sec-
       ond. If this slider is set on the left, there won't be  any  limit,  so
       Liquid  War  will  repaint your screen each time	the fighters move. But
       this can	be a weird behaviour if	your machine is	really	fast,  for  no
       one  cares  about  100  fps per second, one can not even	see them... So
       this paramters limits the refreshment rate, so that there can  be  sev-
       eral  logical  moves of the fichters for	only one screen	refreshing. If
       it is set on its	right, the display is limite to	10 fps,	so you'll have
       to find your setting. I personnally set it right	in the middle, and get
       40 fps. If you press "F5", you'll get the number	of frames per  second,
       and  if you press "F6", you'll get the number of	logical	moves per sec-
       ond. You	can also press "F7" or "F8", and you will get  the  percentage
       of time your computer spends on calculating or displaying the level.

       The "rounds/s" slider allows you	to limit the number of rounds per sec-
       ond. If this slider is set on the left, there won't be  any  limit,  so
       Liquid War will run as fast as possible.	This setting will be of	no use
       if you use Liquid War on	a slow computer	or  if	you  play  with	 hudge
       maps,  but sometimes, with a high-end Pentium class computer, it's sim-
       ply impossible to play on small maps because things simply go too fast.
       So  this	 parameter  is here to help you	and avoid the "10000 moves per
       sec" problem.

       Waves menu

       This is where the wave parameters are set. The waves are	just a graphic
       effect,	which  is  not	really usefull.	I don't	often use waves, but I
       still think they	can sometimes look nice. Change	 these	parameters  if
       you  really  mean to do it, but if you don't understand what they mean,
       it is really OK...

       There are 4 different types of waves, each of them being	defined	by:

       *  An "Ampli" parameter,	to define how big the waves have to be.

       *  A "Number" parameter,	to define how many waves should	 be  displayed
	  at the same time.

       *  A "Speed" parameter, to define how fast the waves should move.

       If  you	want  to  undestand  what the "WX", "HY", "WY",	and "HX" codes
       mean, try to pay	with only one type of wave, the	"Ampli"	 parameter  of
       the  3 other types of wave being	set to 0 (that is to say the slider is
       on its left position), and sea how it looks like.

       The wave	effects	can be toggled during the game by  pressing  the  "F4"
       key.

       Advanced	menu

       This menu allows	the user to change the behaviour of the	fighters.

       The  "Attack" slider sets the agressivity of the	fighters. If it	is set
       on the right, fighters eat each other very fast.	If it is  set  on  the
       left, it	takes ages to fighters to change teams.

       The "Defense" slider sets the capacity that the fighters	have to	regen-
       erate themselves. The more it is	on  the	 right,	 the  faster  fighters
       regenerate.

       The "New	health"	slider sets the	health of the fighters which have just
       changed teams. The more it is on	the left, the  weaker  these  fighters
       will be.

       The  "Winner help" slider controls a parameter which causes fighters to
       attack with various strength depending on how many fighters  belong  to
       their team. Not very clear... Let's just	say that:

       *  If  this  slider  is set on the right, the more fighters you have in
	  your team, the more aggressive they will become.

       *  If it	is centered, all the fighters of every team will always	attack
	  with the same	strength.

       *  If  it  is set on the	left, the less fighters	you have, the stronger
	  they will be.	In this	mode, games usually never end.

       The "Cpu	strength" parameter never makes	the computer more  intelligent
       than  a	monkey.	 But  if  you  set  it on the right, it	advantages the
       machine outrageously and	fighters controlled by the cpu will be	really
       strong.	So  to	get  rid  of them you'll definitely need to be clever.
       Again and again,	don't forget that Liquid War was conceived as a	multi-
       player  game  and  that	playing	 against the computer is not really an
       interesting thing to do.

       The "CPU	vs human" parameter allows you to control how aggressive  CPUs
       are towards humans.

       *  If  set  to  "Always", CPUs will always attack humans	and will never
	  try to attack	another	CPU, unless there are  no  humans  left.  This
	  used to be the default behavior in previous Liquid War versions, but
	  some players remarked	that it	was rather unfair, so now this	is  an
	  option.

       *  If  set to "Random", CPUs won't care wether their opponents are CPUs
	  or humans, they'll attack anybody. This is the default behavior.

       *  It set to "Never", CPUs will	attack	each  other  before  bothering
	  human	players.

       The  "Allow  net	 bots"	button can be used to allow bots to connect on
       network games. Indeed, bots are by default disabled in  network	games,
       since  in this case LW assumes that bots	are useless (there are already
       several human players). However,	turning	this option on will allow  you
       to  connect bots	within the game. It's important	to note	that this is a
       per client option, this means that you can't use	it to forbid access to
       bots  to	 a given network game. This option was simply created to avoid
       confusion when connecting on network games, while still	allowing  bots
       to connects if you really want them to.

       The "Algorithm" parameter allows	you to force the algorithm to standard
       C mode. There's no real good reason you would like to  do  this,	 since
       the C algorithm is slower than the ASM one. Moreover, the ASM algorithm
       is automatically	disabled if you	play against a computer	which does not
       have ASM	enabled. Think of this as a testing/debugging option.

   Hot keys
       Here's a	list of	keys you might use while playing:

       *  F1:  toggles	the  "info"  zone where	the game time and the state of
	  each team is displayed.

       *  F2: moves the	"info" the zone	arround, possible positions being top,
	  right, bottom	and left.

       *  F3: pauses the game. This function is	disabled during	network	games.

       *  F4:  toggles the "wave effect". Without this "wave effect", which is
	  turned on ny default,the game	will run faster.

       *  F5: displays the number of frames per	second (*).

       *  F6: displays the number of rounds per	second (*).

       *  F7: displays the precentage of CPU spent on the game	logic,	calcu-
	  lating where fighters	must go	for instance (*).

       *  F8: displays the precentage of CPU spent on graphics (*).

       *  F9:  turns  on/off  the "capture" mode. In this mode,	screenshots of
	  each frame are taken,	and written to the hard	drive as bitmaps.

       *  F10: quits the game right away without any confirmation prompt, also
	  known	as the "my boss	is coming here!" function.

       (*)  all	 these	figures	tend to	be clearly false as computer go	faster
       and faster. Basically, the time	required  for  "logic"	and  "display"
       operations  is getting shorter and shorter, and the tools I use to mea-
       sure it are not precise enough. Therefore I  get	 approximations	 which
       might by	plainly	wrong.

Network	game
   Basics
       Since release 5.4.0, Liquid War includes	network	support, that's	to say
       that people can play over a LAN (Local Area Network). However,  due  to
       limitations  in	Liquid War's legacy code, and also because of the lack
       of time I have, it might	be a little tricky to set up a network game at
       first. So please	read this section carefully.

       You should keep in mind that:

       *  DOS only releases of Liquid War do not include network support, only
	  Windows and GNU/Linux	versions will allow you	to set	up  a  network
	  game.

       *  The  game  should  run  fine on any LAN, but there's no garantee the
	  game will be playable	on the Internet. Indeed	if your	 "ping	delay"
	  is  not good enough, the game	will be	awfully	slow. Bandwidth	is not
	  an issue, since Liquid War rarely needs more than 2 Kb/sec.

       *  You'll need to know what an IP address is.

       *  You don't need to set	up a network game to run a  multiplayer	 game.
	  Liquid  War  was  originally a multiplayer game without network sup-
	  port.	Network	support	is here	only for people	who  don't  feel  com-
	  fortable when	playing	at 6 on	the same keyboard 8-)

   Getting started
       What do you need?

       You'll basically	need 2 computers connected on the same LAN. We'll call
       them computer A and B. You might	be able	to play	over the Internet too,
       but the game can	be harder to set up and	- which	is worse - very	slow.

       You'll  also need to know the IP	address	of computer A. Type "ipconfig"
       under Windows or	"ifconfig" as root under GNU/Linux to get this	infor-
       mation if you don't have	it.

       Starting	the server

       Liquid  War uses	a very traditionnal client/server approach. Basically,
       the server gets informations from all the clients and  then  dispatches
       the collected information to everybody.

       So  you'll  need	 to  start  a server on	computer A by running "liquid-
       war-server" on GNU/Linux	or "lwwinsrv.exe" on windows. This is  a  con-
       sole application, ie it does not	set up any graphic mode.

       Here's a	small example of a server start	on GNU/Linux:

       $ liquidwar-server
       How many	teams will connect to this server?

       At  this	 point you must	enter a	number between 2 and 6,	and then press
       "ENTER".	In this	example	we will	answer 2. The server really  needs  to
       know  how  many	teams  will be in the game: when enough	teams are con-
       nected, the game	starts.	It can also be a good idea to answer 6 system-
       atically	 and  then force game start by clicking	the "Start now"	button
       within the client. It's possible	to skip	this question by typing	 "liq-
       uidwar-server -2" instead of a plain "liquidwar-server".

       Use "-2"	to get rid of this question.
       Register	on "www.ufoot.org/metaserver/" (y/n)?

       Now  if	we  answer "y",	then the server	will automatically contact the
       "meta-server" and it will  be  listed  on  http://www.ufoot.org/liquid-
       war/v5/metaserver.php3

       This can	be convenient for people who want to find other	gamers to play
       with on the Net.	For now, let's answer "n", we'll test this meta-server
       stuff later 8-)

       Use "-private" to get rid of this question.
       2002-06-03 16:43:00: Listening on port 8035...
       2002-06-03 16:43:00: Waiting for	2 teams...

       Now  the	 server	 is  ready to accept clients. By default it listens to
       clients on port 8035. You could change this behavior setting by calling
       "liquidwar-server  -port	 8061" for instance, but let's use the default
       port to make things easier.

       Starting	the clients

       Start the client	on  computer  A	 normally  by  typing  "liquidwar"  on
       GNU/Linux or double-click "lwwin.exe" on	Windows.

       Go  to  the "Teams" menu	and select 2 teams, a red human	and a blue CPU
       for instance. If	you don't know how to do this, then try	and play  Liq-
       uid  War	 on  a single computer first. It's important to	notice that by
       default the "blue CPU" won't connect on the network game. It's possible
       to  allow  bots	to  connect on network games, but they are disabled by
       default.

       Now come	back to	the main menu, and  a  "Net  Game"  button  should  be
       available. Click	it. Now	you should be able to:

       *  Start	the game.

       *  Change the IP	address	of the server.

       *  Change the communication port.

       *  Set a	password.

       *  Search for internet games automatically.

       Since the server	is also	running	on the same machine (A), you can leave
       the default IP address as is (127.0.0.1).

       Now you are ready to start the second client on computer	B.  Like  with
       computer	A, you'll have to:

       *  Select 2 teams, green	an yellow this time.

       *  Select "Net Game" in the main	menu.

       But  this time you'll also need to change the server address, since the
       client is not running on	the same computer than the server.

       Now click on "Start game" on computer A.	The server should play a "sys-
       tem beep", which	is usefull if you run a	server and want	to be notified
       of client connections without watching the console all the time,	and it
       should display messages like this:

       2002-06-03 16:44:48: Connection from "127.0.0.1:34677"
       2002-06-03   16:44:48:  Team  "Napoleon"	 on  client  "127.0.0.1:34677"
       accepted
       2002-06-03 16:44:49: Client "127.0.0.1:34677" accepted
       2002-06-03 16:44:49: Waiting for	1 team...

       And on the client you should see	a screen which	says  "Waiting	for  1
       team(s)"	 with  the  list of connected players below (Napoleon).	You do
       not need	to click on the	"Start now" button.

       Now click on "Start game" on computer B.	The server should display mes-
       sages like this:

       2002-06-03 16:49:14: Connection from "192.168.1.1:1098"
       2002-06-03  16:49:14:  Team  "Henri  IV"	 on  client "192.168.1.1:1098"
       accepted
       2002-06-03 16:49:15: Client "192.168.1.1:1098" accepted
       2002-06-03 16:49:15: Client "192.168.1.1:1098" ready
       2002-06-03 16:49:15: Client "127.0.0.1:34677" ready
       2002-06-03 16:49:15: Sending info to "127.0.0.1:34677"
       2002-06-03 16:49:15: Sending info to "192.168.1.1:1098"
       2002-06-03 16:49:16: Game start

       And at that point, the game should start	8-)

       Restart a new game

       Once the	game is	over, you  can	start  another	network	 game  on  the
       clients	without	 touching the server, because the server automatically
       restarts	and waits for players to connect.

       To stop the server - if you want	to change its settings for instance  -
       just go to the console where it's running and press CTRL-C.

   Using the meta-server
       Basics

       The meta-server is a piece of software which is running on my web site,
       and allows servers to register themselves so that client	can get	a list
       of available servers.

       It's  written  in PHP and is _very_ basic but I believe it's enough for
       what has	to be done: maintain a list of running servers.

       The source code for the meta-server is included in the  source  package
       of  Liquid War, so you might run	such a server yourself if you want to.
       However,	by default, servers will register themselves on	my  web	 site,
       and will	be listed on http://www.ufoot.org/liquidwar/v5/metaserver.php3

       How to register a server

       Launch the server, and when you get the question:

       Register	on "www.ufoot.org/metaserver/" (y/n)?

       answer "y".

       Note  that  if you're behind a proxy or a firewall, the server might be
       unable to register itself. Clients might	also have problems to  connect
       themselves  on your server if there's a machine which does NAT (Network
       Address Translation) between you	and the	meta-server.

       How to find a server

       In the main menu, click on "Net Game" and  then	"Search	 for  internet
       games".

       Now  you	 should	 see a list of available servers. You can click	on the
       items in	the list to get	more informations about	a given	 server.  Once
       you have	chosen a server, click on "Join	now".

       Now you get on a	"Waiting for teams" screen. You	might be interested in
       using the "Start	now" button. Indeed, if	you are	4 players connected on
       a  server  that accepts up to 6 players,	maybe you'll want to start the
       game right away without waiting for 2 more players. In this case, every
       player  must click "Start now". A "*" character will replace the	"-" in
       the players list	when a player clicks on	 "Start	 now".	When  all  the
       players are displayed with a "*a, the game starts.

       You can also chat with other players by entering	text in	the area above
       the "Send message" button, and then click on this button. Keep in  mind
       that  this is a very primitive chat and that the	best way to chat effi-
       ciently is IMHO to play in windowed mode	and  have  an  IRC  client  at
       hand.

       Note  that  you	can  also  get	the  list  of  available  servers from
       http://www.ufoot.org/liquidwar/v5/metaserver.php3  There	 you'll	  also
       find  a	little chat-box	which will allow you to	send exchange messages
       with other players.

   Options
       Server options

       You can pass options to the server using	the command line. The  follow-
       ing parameters are accepted:

       *  "-n"	where  "n"  is a number	between	2 and 6	: with this option you
	  can tell the server how many teams will connect to the game. Beware,
	  there	 can  be several teams on the same computer, so	if you want to
	  have a computer with 2 players on it and 2 other  computers  with  a
	  single player, then you need to use the "-4" option.

       *  "-lag	n" where "n" is	an integer : with this option, you can control
	  the lag used at startup. Normally, Liquid War	handles	this parameter
	  automatically, but you might want to force it	to a given value.

       *  "-port n" where "n" is an integer : allows you to change the IP port
	  used by the server to	listen to the clients. if you omit this	param-
	  eter,	the default port is (8035) is used.

       *  "-log	 file.log"  :  dumps all informations in "file.log" instead of
	  using	the standard output.

       *  "-public" : skips the	"Register on ..." question, and	registers  the
	  server automatically on the meta-server, so that clients can find it
	  easily.

       *  "-private" : skips the "Register on ..." question, and does not reg-
	  ister	the server at all.

       *  "-comment  This_is_a_comment"	 : associates a	comment	to the server,
	  which	will be	displayed by the meta-server. Note that	the  character
	  "_" will be replaced by spaces. This makes command line parsing eas-
	  ier. I'm lazy	8-)

       *  "-password xxx" : associates a password to  the  server.  With  this
	  option,  clients  will need to give the right	password to be able to
	  connect on the server.

       *  "-callback cmd" : with  this	option,	 the  command  "cmd"  will  be
	  launched whenever someone connects on	an empty server. For instance,
	  if you want to run a permanent server	and want to know when  someone
	  connects  but	do not wish to permanently keep	an eye on the server's
	  log, you might use this option and put in "cmd" a command that auto-
	  matically  sends you a mail. You might also use a command that fires
	  a popup window. It's up to you. 2 sample scripts  are	 available  in
	  the  "misc"  directory of the	Liquid War source distribution.	One is
	  "misc/liquidwar_notify.sh" and works	on  UNIX  platforms,  and  the
	  other	 one  is  "misc/lwpopup.js",  which  is	 automatically used by
	  "misc/lwserver.bat", and works on Windows.

       Common options

       These options work on both client and server, even if they  are	rather
       "server-oriented".

       *  "-metaserver url" : redefines	the URL	of the meta-server. Usefull if
	  you want to use your own meta-server.

       *  "-netlog" : if you use this option, the server  will	dump  all  the
	  network  traffic  on the standard output. This is usefull for	debug-
	  ging.

       *  "-nobeep" : Disables the system beeps	 that  the  application	 might
	  fire.	 These	beeps  are mostly used on the server to	notify clients
	  connections.

   About Liquid	War's network implementation
       Basics

       Liquid War uses TCP sockets, and	a single-threaded server. This implies
       that:

       *  The game can sometimes get blocked if	you play on Internet.

       *  The server can't talk	simultaneously with several clients.

       I needed	to use TCP sockets, since LW's algorithm can not cope with any
       data loss and it's not a	reasonnable to try and anticipate what the map
       would be	like if	the player did not move	etc...

       I  did not implement any	complex	multithreaded stuff since I'm lazy and
       however,	clients	need to	have informations about	all the	 other	before
       something  can  be  done. However, implementing a mutltithreaded	server
       could have advantages over the current solution.

       What is this lag	stuff anyway?

       In Liquid War, all the clients send their key presses  to  the  server,
       and  then  the server dispatches	this information to everyone. This has
       to be done for every round.

       You can easily imagine that if a	player has a poor connection,  with  a
       very  long  "ping  delay",  it  can  take quite a long time to send the
       information to the server, and then get it back.

       So what Liquid War does is that at  the	beginning  of  the  game,  the
       server  sends a couple of "blank" key strokes to	the clients. This way,
       clients receive data from the server before thay	 have  sent  any.  The
       number  of  key strokes sent at the beginning of	the game is called the
       "lag".

       So if it	takes 200 msec to send and then	receive	data from  the	server
       (approx	the time returned by the "ping"	command) then with a lag of 6,
       you can theorically play	at a rate of (1/0.2)*6=30 rounds/sec.

       On one hand, setting the	lag parameter to a high	value will avoid  many
       network	errors	and allow you to play at a very	fast pace, but the big
       drawback	is that	there will be quite a long time	 between  the  instant
       you  send  a  key  stroke to the	server and the moment it comes back to
       you. On the other hand, setting the lag to a low	value will limit dras-
       tically he number of rounds per second, but make	the game more "respon-
       sive".

       However,	since release 5.4.1, the "lag" is modified  automatically  and
       should  adapt itself to the situation. I've not been able to test it in
       real conditions yet, but	it should work 8-)

       Still, setting the lag to a sensible default value can  save  you  some
       trouble.	Indeed,	by default, Liquid War will choose a value (6),	but it
       can not guess if	you are	playing	on Internet or on a 100	Mbit LAN,  and
       it can take quite a long	time before Liquid War automatically finds the
       right value. To know the	right value which  should  be  used  with  the
       "-lag" option, simply play a few	games and watch	the average lag	(which
       is displayed on the server console every	minute)	 at  the  end  of  the
       game.

       Performance issues

       Liquid  War  uses  a  "light" server, and one of	the advantages of this
       solution	is that	it allows you to run the server	on low-end  computers.
       I  personnally  run a permanent server on a 486 DX2, and	it runs	like a
       charm.

       The only	thing you have to take care of when running a server is	 band-
       width. Don't worry, you won't need a 10Mbit connection, basically, each
       clients sends and receives 12 bytes of data at each round. If  you  add
       TCP/IP  headers	and  the  facts	that stuff will	probably be bundled in
       bigger packets, a client	must deliver about 15 Kbit/sec (up  and	 down)
       for  a  game that runs at 100 frames/sec. A 56K V90 modem is enough for
       this.

       So if you run a server with 2 clients connected,	the server  will  need
       to deliver 30 Kbit/sec in both ways. A 56K V90 modem _can_ do that, but
       your provider needs to be a good	one 8-)

       And if you run a	server with 6 clients, you simply  won't  be  able  to
       reach  the 100 frames/sec with a	56K V90	modem. It will necessarly drop
       to something less than 30 frames/sec, and is likely to drop to about 15
       frames/sec.  OK this is not a big deal, since few Internet games	run at
       more than 30 frames/sec,	but well, if the server	has  troubles  receiv-
       ing/sending data, everyone will wait, and the fun will go away.

       As  a conclusion: if you	have the choice, choose	the friend who has the
       best bandwidth to run the server, without even considering the power of
       his computer.

   Troubleshooting
       General information

       Network	support	 in 5.4	and 5.5	is still experimental in many ways, so
       you might get weird behaviors. Basically, if you	have a	problem,  just
       do the following:

       *  Stop	and  restart the server	when something goes wrong. To stop it,
	  use CTRL-C.

       *  Check	out that you have entered the correct IP addresses.

       *  Try and start	the client and the server using	the  "-netlog"	option
	  to have an idea about	what's happening.

       Bugs in 5.4.x corrected in 5.4.2

       Liquid  War  5.4.0  and 5.4.1 were very hard to play over the Internet.
       The reason is that the network routines did not do enough error	check-
       ing,  and  therefore  there  were very often errors when	sending	and/or
       receiving the map to the	server.	Hopefully, this	bug should not	appear
       anymore in 5.4.2	or any other recent release.

   About security
       Network games passwords

       As  you might have noticed, under the box where you can enter the pass-
       word, a little notice explains that you must choose a "weak"  password.
       Now  you'll tell	me -> people keep on explaining	me that	passwords must
       be something complex like "aS\r!Y9p" and	now I'm	told to	 use  "hello",
       what's up?

       OK,  keep  in  mind Liquid War is a game. This password stuff is	just a
       way to be able to play with your	friends	only and  keep	on  using  the
       meta-server's  services.	Liquid War does	not encrypt data and I can see
       no good reason to do it for, so the password is stored and sent to  the
       server in clear,	as plain text.

       The  consequence	 is that if you	use a valuable password	- for instance
       the one you use to log in on your computer  -  the  guy	who  runs  the
       server  will  see your password in the log file if he wishes to.	There-
       fore, use something weak, something that	if someones finds out what  it
       is, you won't really care. So "hello" is	a wise choice.

       Is Liquid War likely to have security holes?

       Yes.

       Any program is likely to	have security holes, especially	when it's net-
       worked. However,	I have good reasons to think that Liquid War  is  safe
       enough  for  a  game. At	least I	find it	safe enough to run a permanent
       public server on	my personnal computer 8-)

       FYI, here are some things which I think make Liquid War rather safe  to
       run:

       *  Liquid  War  does  not  store	anything on your hard drive that would
	  have been received from the network. The maps	are kept  in  RAM.  So
	  you won't download any virus playing Liquid War on Internet.

       *  Liquid  War  does  not transmit any sort of code on the network. All
	  the transmitted bytes	represent plain	data. So you're	not likely  to
	  execute any arbitrary	code - virus, worm - when playing on the Net.

       *  Liquid  War  receives	 network packets in static buffers, and	if the
	  received data	is too big, it is truncated. One consequence  is  that
	  Liquid  War  has a bunch of "limits".	You can't send hudge maps over
	  the network, you can't have long nicknames, and so on.  But  another
	  consequence  is  that	 if  you try to	send garbage in	the buffer, it
	  will be truncated. Liquid War	will protest with  a  "network	error"
	  message and the connection will be closed, but there will be no easy
	  exploit possible here.

       *  Liquid War does not use the sprintf, strcpy  and  strcat  functions,
	  which	are known as being rather unsecure since they can lead to buf-
	  fer overflows. Instead, it uses the equivalent  functions  snprintf,
	  strncpy  and	strncat.  On  platforms	where these functions are sup-
	  ported natively, the game will use  the  default  system  functions,
	  otherwise  it	 will use a free implementation	by Mark	Martinec. FYI,
	  Windows does not support snprintf-like functions natively, that  is,
	  it's a piece of crap.

       *  Liquid War is	Free Software, so I'm not likely to have put backdoors
	  in it	myself,	since anyone can look at the source code 8-)

       However,	I have not - and I know	nobody who has -  audited  Liquid  War
       for  security  holes.  So  there	 might	be  some. Therefore you	should
       respect a few things while running Liquid War:

       *  Never	run Liquid War as root or administrator. This is obvious but I
	  still	 mention  it.  If you want to run a Liquid War daemon on UNIX,
	  run it as user "nobody"  or  something  approaching.	If  "root"  or
	  "administrator"  does	 not make sense	on your	system (DOS, Win98...)
	  then I assume	you're not _really_ concerned  about  security	anyway
	  8-P

       *  If  you  run a server	7/7 24/24, use the "-log" option to log	every-
	  thing	in a file. This	way you'll keep	a trace	of  network  activity,
	  and if something goes	wrong, you might get a chance to see it.

       *  If  you  use	passwords  in network games, *never* choose a valuable
	  password. Use	something simple like "hello" or "goodbye".

       *  Keep in mind that Liquid War is a game, and not a bullet proof  pro-
	  fessionnal server.

       Last  point:  you  should be aware that version 5.4.5 of	Liquid War has
       been proved to be vulnerable to a local buffer overflow,	and one	should
       run  at	least  5.5.9  to  get rid of this problem. FYI by the time the
       exploit	was  found  on	5.4.5,	5.5.9  was   already   out   8-)   See
       http://www.securityfocus.com/bid/8629	 and	http://www.securityfo-
       cus.com/bid/9453	for more informations.

       Can people cheat	when playing on	the Net?

       No.

       Or at least, not	really.	In fact, you  can  still  find	the  following
       types of	lamers:

       *  A guy	who lets the CPU play at his place. He'll loose	anyway because
	  the CPU is definitely	not a great Liquid War Master 8-)

       *  A guy	who tweaks the game and	gets all  his  bots  fight  anyone  he
	  wishes. That's mean.

       *  A  guy  who  manages to let you have a 500msec lag while he does not
	  have any lag at all.

       Apart from this,	I can hardly see any way to cheat.  Why?  Because  the
       Liquid  War  server does	not store any information about	the game. It's
       not aware of who	wins, who looses, it knows nothing. The	only thing  it
       does is to transmit key presses between client computers.

       This way, if someone plays with a tweaked release of Liquid War,	think-
       ing he will fool	you, then he will fool you on his computer only...  On
       your  computer,	everything  will be fine. After	some time, your	screen
       and his screen will have	nothing	in common, and both players are	likely
       to think	they have won. Except the lamer	will stay a lamer.

       This  also  explains  why it's required to play with the	very same ver-
       sions of	the game during	network	games. If you  plug  a	5.5.2  with  a
       5.5.1,  after a minute the screens will be completely different on each
       client, since there are subtle differences between the  5.5.1  and  the
       5.5.2  engine.  However,	you shouldn't be able to do this, since	a net-
       work error will stop you	before you can start to	play.

       Additionnally, versions 5.5.5 and higher	have a checksum	system.	 Every
       100  rounds,  each client calculates a checksum with its	local map, and
       sends it	to the server. If the checksum is incorrect, the  server  will
       log a message like:

       Checksum	error on client	"192.168.1.1:1098"

       If you see this,	then you're in one of the following situations:

       *  There's a bug	in the game

       *  A lamer tries	to cheat

       FYI,  all  releases from	5.4.0 to 5.5.4 have a bug which	causes clients
       to desynchronize	after a	while...

Command	line parameters
   Introduction
       When you	launch Liquid War 5, you can use command line options. If  you
       have no problems	launching Liquid War, this section should not interest
       you very	much.

       You can use several options at the same	time.  The  basic  syntax  for
       options looks like this:

       lw -option1 -option2 parameter2 -option3	parameter3 -option4 -option5

       Note  that  most	 of the	options	are legacy options which where usefull
       with the	initial	releases of Liquid War,	when you had to	run in a  Win-
       dows  DOS  box,	and when there were still plenty of 486	computers with
       only 8Mb	ram...

   Version checking
       These are basic options which  can  be  usefull	to  figure  out	 which
       release of Liquid War is	installed.

       *  "-v" : returns the version number of the program.

       *  "-h" : displays a short description and copyright information.

   Changing default paths
       Very  usefull  options, especially if you can not install Liquid	War in
       default directories or want to put the game in a	special	place.

       *  "-cfg	myconfigfile.cfg" : causes Liquid War  to  use	the  specified
	  config file.

       *  "-dat	 mydatafilefile.dat"  :	causes Liquid War to use the specified
	  datafile. This might be a very interesting option if you run	Liquid
	  War  on a GNU/Linux box where	you do not have	root access and	there-
	  fore can not put the datafile	in /usr.

       *  "-map	mycustommapdir"	: causes  Liquid  War  to  use	the  specified
	  directory as the user	map directory. The user	map directory is where
	  you can put plain bitmaps to be used as maps.

       *  "-tex	mycustomtexturedir" : causes Liquid War	to use	the  specified
	  directory  as	the user texture directory. The	user texture directory
	  is where you can put plain bitmaps to	be used	as textures.

       *  "-mid	mycustommusicdir" : causes Liquid War  to  use	the  specified
	  directory  as	the user music directory. Any midi file	placed in this
	  directory will be added to the list of available musics.

       *  "-server myliquidwarserverfile" : causes Liquid War to use the spec-
	  ified	 file  as the server executable. This option has no effect for
	  now since the	server is not launched by the client.

       *  "-mapgen mylwmapgenfile" : causes Liquid War to  use	the  specified
	  file as the "lwmapgen" executable. "lwmapgen"	is an utility by David
	  Redick which generates random	maps automatically for Liquid War. You
	  might	 wish  to change this option if	random map generation does not
	  work for some	reason,	or if you want to use your own map generator.

   Troubleshooting switches
       These options give you control on how Liquid War	treats	initialisation
       errors,	how much memory	it should reserve, what	kind of	video mode sit
       should not choose etc...

       *  "-vga" : This	option forces Liquid War to use	your video card	as  if
	  it  was  only	 a basic VGA card. This	option is required if you play
	  Liquid War from Windows NT.

       *  "-no400300" :	This option disables the VGA  400x300  video  mode.  I
	  created this options for I know that some video cards/monitors don't
	  support the 400x300 mode.

       *  "-silent" : With this	option,	Liquid War will	not play any sound. It
	  will	not  search for	any sound card.	This can be interesting	if you
	  don't	have any sound card or if Liquid War doesn't handle your  card
	  correctly.

       *  "-nowater" : Causes Liquid War not to	load any water sound. Use this
	  if Liquid War	runs short of memory, and you should gain about	850kb.

       *  "-nosfx" : Causes Liquid War not to load any sound fx. Use  this  if
	  Liquid War runs short	of memory, and you should gain about 150kb.

       *  "-nomusic" : Causes Liquid War not to	load any midi music.

       *  "-mem	 n" : The parameter "n"	sets the amount	of memory (in Mb) Liq-
	  uid War will allocate	to do all its calculus.	If this	number is  too
	  small,  you  won't  be  able to play on all the levels. If it	is too
	  high,	Liquid War may not start at all	or crash while you  are	 play-
	  ing. The default value is 8. If you play Liquid War from Windows and
	  Liquid War refuses to	run because this parameter is too  high,  then
	  try and give more dpmi memory	to Liquid War.

       *  "-nojoy" : This option disables joystick support.

       *  "-noback"  : Causes Liquid War not to	load the background image. Use
	  this if Liquid War runs short	of memory, and you should  gain	 about
	  300kb.

       *  "-notex"  :  Causes  Liquid War not to load any texture. Use this if
	  Liquid War runs short	of memory, and you should gain about 750kb.

       *  "-auto" : If you set this option,  Liquid  War  won't	 generate  any
	  error	while allocating memory	or loading data.

       *  "-safe"  :  With this	option,	you will play with a very reduced ver-
	  sion of Liquid War. It looks rather ugly but should work  in	a  DOS
	  box with only	4Mb of DPMI memory. Use	this if	you experience serious
	  memory or device problems. If	Liquid War  doesn't  start  with  this
	  option turned	on, I really don't think I can do anything for you...

       *  "-nice"  :  With  this  option,  Liquid War will use a mode which is
	  between the default mode and the "safe" mode.

       *  "-check" : With this option, Liquid War will	stop  as  soon	as  it
	  detects something strange while initializing.

       *  "-stop"  :  If you set this option, Liquid War will prompt you for a
	  key when the init process is completed.

       *  "-c" : This is a weird option, if you	turn it	on, the	game will only
	  use  fonctions which are programmed in C langage. The	default	behav-
	  iour is to use some functions	I rewrote in assembly langage, so that
	  the game is a	little faster.

   Debug options
       These  options  are  usefull  if	 you  want to debug the	game and trace
       what's happening.

       *  "-netlog" : Dumps all	the network traffic on	the  standard  output.
	  This	can help finding problems when trying to connect to the	server
	  in a network game.

   Server options
       The server command line options are  described  in  the	section	 which
       deals  which  network games in general. IMHO you	need to	understand how
       network works in	LW before trying to tweak the server 8-)

   Other options
       Everything else 8-)

       *  "-capture" : Activates the capture mode. In this mode, the game will
	  dump a .bmp file on the disk several times per second, which is use-
	  full if you want to create an	mpeg movie of your game	session	after-
	  wards.  You can also activate	this mode interactively	by pressing F9
	  within the game.

       *  "-metaserver url" : redefines	the URL	of the meta-server. Usefull if
	  you want to use your own meta-server.

       *  "-nobeep"  :	Disables  the  system beeps that the application might
	  fire.	These beeps are	mostly used on the server  to  notify  clients
	  connections.

       *  "-tombola" : Activates a special mode	where scores are not displayed
	  normally. Instead, the game displays 3 random	numbers	 between  1  -
	  500.

   lwmapgen options
       The  external lwmapgen program by David Redick accepts a	number of com-
       mand line options. You can type:

       liquidwar-mapgen	--help

       to get a	list of	all available options under UNIX.  Under  Windows  the
       command would be:

       lwwinmap	--help

       Note that lwmapgen is called automatically by Liquid War	when you click
       on the "Random map" button.

       The idea	behind lwmapgen	is that	you choose a function which  sets  the
       type  of	 map  generated, and then pass various arguments to this func-
       tion. If	you do not explicitly choose a function, one will be picked up
       for you randomly, and all other parameters will use default values.

       The most	usefull	and common options are:

       *  "--help" : displays help.

       *  "--out filename" : save bitmap to filename.

       *  "--size n" : bitmap size (an integer between 0 and 5).

       *  "--list" : list all available	functions.

       *  "--function function_name" : which function to use.

       Here's a	typical	use of lwmapgen:

       liquidwar-mapgen	--size 3 --function hole --out test.bmp

Platform specific issues
   General remarks
       Liquid  War is now a cross-platform game, thanks	to Allegro. So now you
       can play	under different	OS.

       The same	source tree will compile on all	supported platforms, but  with
       slight  differences  when  running. C preprocessor #defines are used to
       code some platform specific stuff, and in some cases there are  differ-
       ent files for the DOS, Windows and UNIX versions.

       As I said, I try	to use the same	code for all platforms.	This is	in the
       long term the best choice. Otherwise there would	different branches  of
       the source tree,	and I don't think this is a very good solution.

       Therefore  some	optimizations  that were performed in the old DOS-only
       version have been totally removed, for they were	100%  platform	depen-
       dent  (ie  mode-X  asm  coding).	 So  the new versions are all a	little
       slower than the old 5.1 stuff, but the performance loss is  only	 about
       20%, which is not significant with today's PCs. And anyways the perfor-
       mance loss is most of the time limited to the goog  old	VGA  320x200x8
       mode-X, which starts being kind of obsolete.

   DOS
       This  is	 the  original version.	It's the fastest one as	far as I know,
       the safest one and it will always be I think, since Allegro  was	 first
       designed	 for  DOS,  and	DOS allows a full unconditionnal access	to all
       the hardware ressources LW requires. LW doesn't use any hardware	accel-
       eration	and  it's not been designed to do so. Unfortunately there's no
       network support for the DOS version of Liquid War.

   Windows
       When running under a Windows box, the DOS release used to be safer than
       the  native  Windows  port. Now that DOS	support	is getting really poor
       with recent versions of Windows,	the native Windows release  of	Liquid
       War  starts  begin  the	good choice for	Windows	users. And Allegro for
       Windows is getting quite	stable in the 4.x series.

       The other reason	to choose this release rather than the DOS release  is
       that it has network support.

       If you have problems running Liquid War under Windows, please check out
       the "data\lwwin.log" file which should be written each time you run the
       game.  It  contains  the	 information which is displayed	on the console
       under other platforms, and might	give you a  clue  about	 what's	 going
       wrong.

   GNU/Linux
       This port is the	most recent one, and also the one I prefer. Paths have
       been changed to an UNIXish style, ie the	data is	stored in:

       /usr/local/share/games/liquidwar

       the executable in:

       /usr/local/games

       and the configuration file is

       ~/.liquidwarrc

       Since not all GNU/Linux distributions have  /usr/local/games  in	 their
       path,  I	 also put a symbolic link to the binaries in /usr/local/bin. I
       believe Liquid War is quite FHS compliant, so if	its  default  directo-
       ries do not match your configuration, blame your	distro for not follow-
       ing  the	 standards  8-)	  AFAIK	  the	only   touchy	directory   is
       /usr/local/share/pixmaps	 which I've seen on many distribution but does
       not seem	to be referenced in the	FHS.

       With the	latest releases	of Allegro, Liquid War is becoming pretty sta-
       ble  under  GNU/Linux.  You should also know that the GNU/Linux port is
       usually the most	up to date, since I very very seldom boot  Windows  at
       home and	do most	of the coding under GNU/Linux.

   FreeBSD
       This  is	 the  latest  port,  so	 I  expect it to be a little touchy to
       install and/or run for some time.

       Note that to compile the	game you'll need to  install  GNU  tools  like
       gmake  and  gcc.	 Liquid	War won't compile with the genuine make	and cc
       commands.

       One thing you might ask is: "why	do you provide the binary as  a	 plain
       .tgz  file,  it would be	much nicer if a	standard FreeBSD port was pro-
       vided instead!".	The answer is that the statically linked binary	should
       work flawlessly and does	not raise any dependency problem. Also I don't
       know how	to make	a BSD port and I'm not really interested in doing  it.
       If  it's	 easy to do, then someone can simply do	it and send it back to
       me. If it's hard	to do, then I do not really have the time nor  motiva-
       tion  to	do it. What I did is make the code and install scripts FreeBSD
       friendly	so that	it would be possible to	compile	the game  under	 Free-
       BSD. Packaging is another story.

   Mac OS X
       There's	currently  a  beta  version of a Mac OS	X port for Liquid War.
       Ryan D. Brown nicely managed to compile and run the game	under  Mac  OS
       X,  and	the  latest  news was that it does basically work. Still, this
       port did	not go through intensive testing, so there might still be some
       bugs, expecially	concerning networking.

       There  were  some  byte	endianess  problems  in	 previous  ( <=5.5.8 )
       releases	of LW, but I tried to fix them and they	should be gone now.

       As of today, we're trying to find out a convenient way to  package  and
       release	the  Mac OS X version of LW. You can contact us	on the mailing
       list if you're interested in this port.

User levels
   A piece of advice
       You can use your	own levels whith Liquid	War 5. The only	thing you have
       to  do  is to put your own 256-colors vbitmap files in a	special	direc-
       tory, and the program will use them. Currently, BMP, LBM, PCX, and  TGA
       files  are supported. It	is a good thing	to use 256 colors bitmaps, for
       they waste less disk space than truecolor bitmaps,  and	Liquid	War  5
       converts	 all  bitmaps  to  32 colors bitmaps. Additionnally, truecolor
       bitmaps might cause the DOS version to crash randomly...	 2-color  bit-
       maps will also cause the	program	to crash. I warned you!

       The  best thing you can do to create your user levels is	to have	a look
       at the few user files I put in the .zip file and	try  at	 first	to  do
       something that looks about the same!

   Maps
       Liquid  War  5  does  many checks on user levels	and is much safer than
       Liquid War 3. Still, try	and help the program not to crash,  if	possi-
       ble.

       Liquid  War  considers that dark	colors are walls and bright colors are
       associated to the playable area.	So you can draw	your walls  in	black,
       dark  blue,  etc...  And	the rest of the	map can	be of any bright color
       such as white or	yellow.

       You can draw a small map	on a big bitmap, as long as you	use  a	bright
       background  color. Liquid War will autodetect the range of your map and
       add the border line if necessary.

       Liquid War re-orders all	the maps, so that the smallest ones are	on the
       left  and  the  most complicated	ones on	the right when you choose them
       with the	slider in the "map" menu. So if	you can't  find	 the  map  you
       just  draw, don't worry,	it is probably just mixed with the levels from
       the .dat	file.

       The  default  path  for	maps  is   "custom\map\"   on	windows,   and
       "/usr/local/share/games/liquidwar/map" on GNU/Linux.

   Textures
       All  you	 have  to do is	put a bitmap in	the default directory which is
       "custom\texture\"  on  windows,	 and   "/usr/local/share/games/liquid-
       war/texture" on GNU/Linux.

   Textures
       As  of  Liquid  War 5.6.x, it's possible	to associate a map with	a tex-
       ture. All you need is to	call the maps with  the	 same  name  (case  is
       important,  lowercase  recommendend...).	 Look at the "meditate"	custom
       map which is shipped with Liquid	War for	instance.

       This also works	with  internal	builtin	 maps  (those  stored  in  the
       datafile)  so for instance if you name a	custom texture "world1.bmp" it
       will automatically be associated	to the builtin map world1  (to	figure
       out  internal names you have to unpack the source distribution and look
       in the ./data directory). This also works the other way,	if you name  a
       map  "wood2.bmp"	 it  will be automatically associated with the builtin
       texture wood2.

       Associating a texture with a map	requires more work  than  designing  a
       simple  map,  but  the results is usually much nicer. See the "Kasper -
       ..." series of maps for instance.

   Send	your levels
       Maybe you will find that	the original levels are	ugly  and  unplayable.
       Well,  if you have made user levels and think they are great, just send
       them to the Liquid War user mailing list. Please	use  only  256	colors
       bitmap  and zip them before sending them, or else they might be blocked
       by my provider...

       As of today, dozens of user maps	have already been included  in	Liquid
       War,  this  is very nice	for it happens that every map designer has his
       own personnal tastes, so	the maps all look different.

       Still, to be included in	Liquid	War's  mainstream  distribution,  your
       maps  will  need	to be placed under the terms of	the GNU	General	Public
       License,	or at least a compatible license. You should have  received  a
       copy of this license with Liquid	War anyway. Read it 8-)

       Of course, you can use *any* map	when playing. You can even play	with a
       bitmap you got from a proprietary source	- such a proprietary game  you
       bought  for  instance  -	 but the point is that I can't - and you can't
       either -	distribute such	a map along with Liquid	War.

       However,	this is	enough legal boring stuff! What	 you  should  keep  in
       mind  is	 that  I'm  always happy when I	receive	maps from players, and
       it's a pleasure for me to include them in the mainstream	distribution.

Core algorithm
   Introduction
       General remarks

       If you have played Liquid War, you must have  noticed  that  your  army
       always  takes  the shortest way to reach	the cursor. So the fundamental
       stuff in	Liquid War is path-finding. Once you've	done that the game  is
       quite  easy  to code. Not harder	than any other 2D game.	Still the path
       finding algorithm is an interesting one,	for it's not a	common	method
       that we used.

       Basically,  at  each round (by round I mean a game logical update, this
       occurs 10 or 100	times/sec depending on the level and/or	your machine),
       the  distance from all the points of the	level to your cursor is	calcu-
       lated. Now the point is to calculate this fast, real fast. In  fact,  a
       "gradient" is calculated	for all	the points of the level, and the value
       of this gradient	is the distance	required for a little pixel/fighter to
       reach  your cursor, assuming that he takes the shortest way. Liquid War
       does this with a	10% error tolerance, and it's enough for  keeping  the
       game interesting.

       Once  you  have	this  gradient	calculated, it's not hard to move your
       fighters. Basically, you	just have to move  them	 toward	 the  adjacent
       point  that  has	 the  lowest gradient value, ie	is the closest to your
       cursor.

       History

       The Liquid War algorithm	has been invented by my	friend Thomas  Colcom-
       bet  In fact the	Liquid War algorithm has been invented before the game
       itself. The game	came as	 a  consequence	 of  the  algorithm,  he  just
       thought "mmm, cool, we could make a game	with that!".

       Later, I	enhanced the algorithm,	as I coded it. The consequences	were a
       performance increase, especially	on simple but big levels. I mean  lev-
       els with	wide areas for teams to	move. Still the	basis of the algorithm
       remained	the same.

       Pros

       The Liquid War algorithm	for path-finding is very efficient:

       *  When you have	to move	lots of	different  points  toward  one	single
	  point. Good thing that's the rule of Liquid War!

       *  When	you  have no clue about	how your map will look like, ie	if the
	  walls	are randomly placed.  The  complexity  of  the	level  doesn't
	  influence  much  the	speed of the algorithm.	The size does, but the
	  complexity, ie the number of walls, is not so	important.

       Cons

       The Liquid War algorithm	is very	 poor  compared	 to  other  algorithms
       when:

       *  You have several target destinations,	that's to say Liquid War would
	  be really slow if there were 100 teams with 10 players only.

       *  You want to move one single point only.

       *  > You	want the exact (100% sure) path. In fact, this algorithm finds
	  solutions  which  approach the best one but you can never figure out
	  if the solution you found is the best, and the algorithm never ends.
	  In  the  long	 term,	the algo will always find the best solution or
	  something really close but I don't know any easy way to  figure  out
	  when you have	reached	this state.

   Mesh
       Introduction

       The first Liquid	War algorithm used to calculate	the gradient (the dis-
       tance from a point to your cursor) for every single point of the	map.

       With Liquid War 5, I used a mesh	system.	This mesh system is  a	struc-
       ture  of	squares	connected together. Squares may	be 1,2,4,8 or 16 units
       large or	any nice value like that, and the gradient is only  calculated
       once  for  each square. Squares have connections	between	them, and each
       connection is associated	to a direction.

       There are 12 directions:

       *  North-North-West (NNW)

       *  North-West (NW)

       *  West-North-West (WNW)

       *  West-South-West (WSW)

       *  South-West (SW)

       *  South-South-West (SSW)

       *  South-South-East (SSE)

       *  South-East (SE)

       *  East-South-East (ESE)

       *  East-North-East (ENE)

       *  North-East (NE)

       *  North-North-East (NNE)

       Example

       Well, let me give you an	example, supposing that	 you  level  structure
       is:

       **********
       *	*
       *	*
       *       **
       *	*
       **********

       The * represent walls, that's to	say squares where fighters can not go.

       Then the	mesh structure would be:

       **********
       *11112233*
       *11112233*
       *1111445**
       *i1114467*
       **********

       In this mesh, there are 7 zones:

       *  zone 1 has a size of 4. It's linked with zones 2 (ENE) and 4 (ESE).

       *  zone	2 has a	size of	2. It's	linked with zones 3 (ENE,ESE), 5 (SE),
	  4 (SSE,SSW) and 1 (SW,WSW,WNW).

       *  zone 3 has a size of 2. It's linked with zones 5 (SSW), 4 (SW) and 2
	  (WSW,WNW).

       *  zone	4 has a	size of	2. It's	linked with zones 2 (NNW,NNE), 4 (NE),
	  5 (ENE), 6 (ESE) and 1 (WSW,WNW,NW).

       *  zone 5 has a size of 1. It's linked with  zones  3  (NNW,NNE,NE),  7
	  (SE),	6 (SSE,SSW), 4 (SW,WSW,WNW) and	2 (NW).

       *  zone	6  has	a  size	 of  1.	 It's linked with zones	5 (NNW,NNE), 7
	  (ENE,ESE) and	4 (WSW,WNW,NW).

       *  zone 7 has a size of	1.  It's  linked  with	zones  5  (NW)	and  6
	  (WSW,WNW).

       Why such	a complicated structure?

       Because it allows the module which calculates the gradient to work much
       faster. With this system, the number of zones is	 reduced  a  lot,  and
       calculus	 on  the  mesh	can  go	very fast. At the same time, this mesh
       structure is complicated	to understand by us humans but it's very  easy
       for the computer.

   Gradient
       Introduction

       For  each  zone defined in the mesh, LW calculates an estimation	of the
       distance	between	the cursor and this zone.

       The algorihm is based on	the fact that to cross a zone which size is n,
       n movements are required. Easy, eh?

       Description

       Here's the way the algorithm works:

       for each	turn of	the game, do:

       *  pick	up a direction between the 12 defined directions. They have to
	  be chosen is a peculiar order	to avoid weird behaviors  from	fight-
	  ers,	but  let's suppose we just pick	up the "next" direction, ie if
	  WSW was chosen the last time,	we pick	up WNW.

       and then	for each zone in the mesh, do:

       *  Compare the potential	of the current zone with that of its  neighbor
	  zone.	The neighbor zone to be	chosen is the one which	corresponds to
	  the direction	which has been previously picked up, and by  potential
	  I  mean  "the	 distance  to the cursor, estimated by the algorithm's
	  last pass".

       *  If potential_of_the_neighbor_zone > (potential_of_the_current_zone +
	  size_of_the_current_zone)   then   potentiel_of_the_neighbor_zone  =
	  potential_of_the_current_zone	+ size_of_the_current_zone

       How can this work?

       Well, just ask my friend	thom-Thom, he's	the one	who had	 the  idea  of
       this algorithm!

       The  basic  idea	is that	by applying this simple	rule to	all the	zones,
       after a certain amount of time, it's impossible to find	any  place  in
       the  mesh  where	 the  rule is not respected. And at this time, one can
       consider	the potiential is right	in any point.

       Of course when the cursor moves the potential has to  be	 recalculated,
       but you see, cursors move really	slowly in Liquid War, so the algorithm
       has plenty of time to find a new	stable solution...

       Demo

       It's possible to	see this algorithm working by typing:

       ufootgrad[n]

       while playing, where [n]	is the number of  the  team  the  gradient  of
       which you want to view. The game	is still running but you view a	team's
       gradient	being calculated in real time instead of seeing	the fighters.

       If you type ufootgrad0 the display comes	back to	normal mode.

   Move
       Introduction

       Once the	gradient is calculated for any zone on the  battlefield,  it's
       quite easy to move the fighters,	hey?

       The following method is used to move the	players:

       *  A "main direction" is	chosen for the fighter,	this direction is cho-
	  sen using the	gradient calculated on the mesh.

       *  Knowing which	direction is the main one, a "level  of	 interest"  is
	  applied to the 12 defined directions.

       There are 4 "level of interest" for directions:

       *  Main directions: the direction calculated.

       *  Good	directions:  these  directions	should lead the	fighter	to the
	  cursor.

       *  Acceptable directions: ok, one can use  this	direction,  since  the
	  fighter shouldn't loose any time using it.

       *  Unpossible directions: wether	there's	a wall or using	this direction
	  means	the fighter will be farer from	his  cursor  than  before,  it
	  always means that this direction will	not be used, never.

       Rules

       The  fighters will try to find any matching situation in	this list, and
       chose the first one.

       *  The main direction is	available, no one on it, OK, let's follow it.

       *  There's a good direction with	no one on it, OK, let's	follow it.

       *  There's an acceptable	direction with no one on it, OK, let's	follow
	  it.

       *  The  main  direction	is available, but there's an opponent on it, I
	  attack! By attacking,	one means that	energy	is  drawned  from  the
	  attacked  fighter and	transmitted to the attacker. When the attacked
	  fighter dies,	he belongs to the team which killed him.

       *  A good direction is available, but there's  an  opponent  on	it,  I
	  attack!

       *  The  main  direction	is available, but there's a mate on it,	I cure
	  him. That's to say that energy is given to the mate. This way,  when
	  there's  a big pool of fighters from the same	team, they re-generate
	  each other.

       *  None of the previous situations found, do nothing.

       Tips and	tricks

       The behavior of the armies is quite tricky to set up. I had  myself  to
       try  many algorithms before I came to something nice. In	fact, I	had to
       introduce some "random" behaviors. They are not	really	random	for  I
       wanted  the game	to behave the same when	given the same keyboard	input,
       but for instance, fighters will prefer NNW to NNE sometimes, and	NNE to
       NNW  some  other	times. By the way, I think Liquid War could stand as a
       nice example of the thoery of chaos.

Source code
   General remarks
       Modularity

       Liquid War 5 is basically a big C program.  I've	 splitted  the	source
       code  in	many small files for I do not like to have to handle big mono-
       lithic sources, but this	does not mean Liquid War is very  modular.  In
       fact Liquid War 5 is quite bloated with global variables	and other ugly
       stuff 8-(

       Coding style

       To be honest, it's a big	mess. You won't	find 2 files coded in the same
       maner...	 OK,  I'm  exagerating a bit. From now I try to	make an	effort
       and stick to basic rules	such as:

       *  use the GNUish-style indentation - the default Emacs mode in fact

       *  prefix global	 functions  /  variables  /  constants	/  types  with
	  lw_<NAME_OF_THE_file>_. For instance,	a "do_it" function in myfile.c
	  will be called lw_myfile_do_it

       *  use capitals for constants, globals and types	 only.	All  functions
	  are in lowercase with	"_" to separate	words

       *  keep	on using 8.3 filenames for .c source files. This is for	better
	  DOS integration. DOS version of Liquid War is	still maintained,  you
	  know 8-)

       *  use English only for code and	comments

       I  might	decide to rename and cleanup everything	some day, for it would
       help other coders to understand what I wrote, but well,	this  is  cer-
       tainly not a thrilling task 8-/

   Source files	organization
       Main game code

       Here  you'll  find  the	main()	function, the main game	loop, applica-
       tion-wide constants and other global stuff.

       It might	be a good start	if you want to hack the	code.

       *  base.h: contains global constants used in many different files.

       *  game.c / game.h: contains the	main game loop.

       *  main.c / main.h: the file where the main  C  function	 is  declared.
	  Doesn't  contain  much except	calling	init functions and running the
	  GUI.

       Menus

       The menus are coded using the Allegro GUI system. While this system  is
       very  powerfull,	it's IMHO not adapted to very complex GUIs, and	one of
       its drawbacks is	that it's not  so  easy	 to  redesign  something  once
       you've coded it.

       Besides,	 when  I  started coding the GUI in 1998, I did	it in a	rather
       ugly way, and now I'm paying for	my being lazy at that  time,  since  I
       spent hours coding when I want to change	something 8-/

       *  about.c / about.h: contains the code for the about menu.

       *  advanced.c / advanced.h: contains the	GUI advanced options menu.

       *  connect.c  /	connect.h:  contains code for the "connect" menu which
	  displays which players are connected to the server, before the  game
	  actually starts.

       *  controls.c / controls.h: contains the	code for the controls menu.

       *  graphics.c / graphics.h: code	for the	graphic	options	menu.

       *  internet.c  /	 internet.h:  contains	the  code  for the "Search for
	  Internet games" menu,	where one can pick up a	running	 server	 auto-
	  matically with the help of the meta-server.

       *  language.c / language.h: contains the	code for the "Language"	menu.

       *  level.c  /  level.h: contains	code for the menu where	the player can
	  select a level and its options (texture or color).

       *  menu.c / menu.h: contains the	code for the main menu.

       *  netgame.c / netgame.h: contains the code for the net game menu.

       *  options.c / options.h: contains the code for the options menu.

       *  play.c / play.h: contains the	code which ties	the menu to  the  main
	  gameloop.

       *  rules.c / rules.h: code for the rules	menu.

       *  score.c / score.h: functions to display the scores at	the end	of the
	  game.

       *  speeds.c / speeds.h: contains	the code for the speeds	menu.

       *  team.c / team.h: code	for the	team  menu,  where  one	 choses	 which
	  teams	will play.

       *  volume.c / volume.h: code for	the sound menu.

       *  wave.c / wave.h: code	for the	wave menu.

       GUI tools

       These files contain various utilities which are used in the menus.

       *  alleg2.c  /  alleg2.h:  contains  some  tweaked allegro functions. I
	  wanted to use	bitmaps	with sevral colors for my  fonts,  and	change
	  some	of  the	allegro	default	behavior. So rather than modifying the
	  allegro source code right in the library I copied it	in  this  file
	  and then modified it.

       *  back.c / back.h: this	modules	displays the background	image.

       *  dialog.c / dialog.h: contains	code for standard dialog boxes.

       *  error.c / error.h: contains functions	to display error messages once
	  the game is in graphical mode.

       *  help.c / help.h: generic  functions  to  display  the	 various  help
	  pages.

       Core algorithm

       Here's  *the*  interesting part.	All the	rest of	the code is just sugar
       coat to display stuff, receive players commands,	communicate with other
       computers, handle errors, etc...	But the	real thing is here!

       It's funny to note that these files have	almost not been	modified since
       Liquid War 5.0.

       It's also interesting to	note that they represent a small percentage of
       the  total  amount  of  code in the game. This tends to prove - and I'm
       convinced of it - that game programming does not	only consists in  hav-
       ing  great  ideas,  but also requires a lot of "dirty" and boring work.
       Honestly, coding	an option menu is as boring as coding Liquid War algo-
       rithm is	fun.

       *  fighter.c  /	fighter.h:  contains code to move the armies, once the
	  gradient has been calculated.

       *  grad.c / grad.h: this	module calculates the gradient for each	 team.
	  One  could  say it's the "kernel" of the game, since most of the CPU
	  time is spent	in this	module (except if you have a slow display...).

       *  mesh.c / mesh.h: contains code to set	up a usable mesh with  a  map.
	  Mesh	are re-calculated at each time a new game is started, the rea-
	  son for this being that meshes are *very* big	so  it	would  not  be
	  reasonnable to save them directly on the HD.

       *  monster.s / monster.h: assembly functions to speed-up	the game. It's
	  a replacement	for some fighter.c functions.

       *  spread.s / spread.h: contains	assembly replacements for  some	 func-
	  tions	 of  grad.c.  These replacements do the	same than the original
	  ones from grad.c, but	faster.	Could still be optimized.

       Moving cursors

       It looks	like nothing, but moving a cursor and deciding where it	should
       go if there's a wall in front of	it is not that easy, especially	if you
       want things to work nicely.

       *  autoplay.c / autoplay.h: contains the	code for the computer AI. This
	  module  simulates keypresses from the	computer, then the computer is
	  handled as any other player.

       *  move.c / move.h: provides an API to move the cursors.

       User input

       Until 5.4.0, Liquid War did not have network support. As	it is designed
       to  be multiplayer, one needed to have several players on the same com-
       puter. The mouse	also needed to be handled in a special way since  cur-
       sors  can  *not*	 pass walls in Liquid War. Additionnally, I wanted all
       input channels (keyboard	mouse and joystick) to be handled in a unified
       way.

       This  explains  why there's so much code	for user input,	when one would
       think at	first sight that "polling the keyboard is enough".

       *  joystick.c / joystick.h: contains code to support joystick input. It
	  wraps	 joystick  buttons  to virtual keyboard	keys, so that joystick
	  and keyboard behave exactly the same.

       *  keyboard.c / keyboard.h: contains code to handle key presses.

       *  mouse.c / mouse.h: wraps the mouse  movements	 to  virtual  keyboard
	  keys.	This way the mouse can be used to control the players.

       Initialisations

       These  files  contain  functions	 to intialize various game components.
       100% boring code.

       *  area.c / area.h: contains functions to create	the game  area.	 Basi-
	  cally	 it  contains functions	to create the data structures in which
	  the level is stored during the game.

       *  army.c / army.h: functions to	create the armies, and place  them  on
	  the battlefield.

       *  asm.c	 /  asm.h:  various  constants,	macros and utilities to	ensure
	  that asembly code works correctly.

       *  bigdata.c / bigdata.h: I had a really	 hard  time  with  the	malloc
	  function  with DJGPP under Win95 dos box. I tried to have it working
	  for hours and	hours but my program kept being	buggy. So I decided to
	  allocate  the	 memory	 myself, in a memory zone I create at startup.
	  This is what this module does: create	a huge memory  zone  and  then
	  give parts of	it to the rest of the program.

       *  config.c / config.h: contains	everything that	is related to the game
	  configuration. This module contains  in  global  variables  all  the
	  parameters that are stored in	the config file.

       *  cursor.c / cursor.h: contains	the code to init the cursors and place
	  them on the battlefield at the beginning of the game.

       *  decal.c / decal.h: This module makes	the  link  between  teams  and
	  players.  Its	 coding	 is  quite ugly, for some modules in LW	assume
	  that when 2 teams are	playing	they are always	teams 0	and 1. So when
	  3  teams  are	playing	are playing and	the second team	loses, one has
	  to make team 2 become	team 1.	That's what this module	is for.

       *  exit.c / exit.h: contains code that is executed when the game	 ends,
	  it shuts down	Allegro	and displays messages on the console.

       *  gfxmode.c  /	gfxmode.h:  contains  code to set up the various video
	  modes, and defines which modes are available for each	platform.

       *  init.c / init.h: contains code to  initialize	 Allegro  with	proper
	  options and analyze failures.

       *  palette.c / palette.h: contains function to set up the current color
	  palette. Liquid War uses different palettes, depending on what  col-
	  ors are chosen for teams.

       Graphics

       Here lies most of the graphic functions in Liquid War. There's not that
       much code since Liquid War's strength is	not its	 visual	 effects,  but
       rather its gameplay.

       The only	"funny"	thing is the wave effect. I'm quite happy with it, and
       honestly, I do think it is rather fast, given the fact that it uses  no
       3D hardware at all.

       *  disp.c / disp.h: contains functions to display the battlefield.

       *  distor.c  /  distor.h: this module contains code to create the "wave
	  effect". It uses a lot of data tables, and is	quite  complicated  to
	  understand...

       *  glouglou.s  /	 glouglou.h:  assembly module, it is a replacement for
	  some functions of distor.c. It goes much faster but does the same.

       *  info.c / info.h: contains code to display the	info bar. The info bar
	  is the bar which display the time left and the amount	of players for
	  each team while the game is running.

       *  message.c / message.h: provides an API to  display  messages	during
	  the  game.  Very useful if you want to debug the game: you can trace
	  and display anything.

       *  pion.c / pion.h: contains code to display the	cursors.

       *  viewport.c / vieport.h: code to allocate and resize the  zone	 where
	  the map is displayed,	also called "viewport".

       Sound and music

       Sound  and  music  routines required some encapsulation,	since the game
       must be able to run even	if the sound and/or music did  not  load  cor-
       rectly.

       *  music.c / music.h: contains the code to control MIDI playback.

       *  sound.c / sound.h: functions to play sound.

       Data management

       These functions handle the datafile contents and	also the custom	data.

       Note  that the various utilities	such as	liquidwarcol, liquidwarmap and
       liquidwartex do not share code with the main executable.	This is	 obvi-
       ously  a	design error, for liquidwarmap will handle maps	in a very poor
       way and is unable to autodetect map errors, whereas the	game  does  it
       rather well. Blame the programmer.

       *  disk.c  / disk.h: contains all the code to access data from the hard
	  drive. In fact, all the HD access is done at startup.

       *  map.c	/ map.h: contains code to load the maps	from  a	 datafile  raw
	  data or a user defined bitmap	to a usable structure in RAM.

       *  maptex.c  /  maptex.h: contains code to handle the "use default tex-
	  ture"	option,	and associate a	map with  a  given  texture  automati-
	  cally.

       *  texture.c  /	texture.h:  contains code to handle textures. Textures
	  are stored in	a special format which uses 5 bits per pixel.

       Random map generator

       Liquid War has a	"generate  random  map"	 feature  which	 is  available
       within  the  game  and also as an external program. The source code for
       the external program is in ./utils/lwmapgen in Liquid War  source  dis-
       tribution.  This	program	has been coded by David	Redick,	is also	avail-
       able  on	 http://www.cs.clemson.edu/~dredick/lwmapgen/  and  works   on
       GNU/Linux.  Compiling this program under	DOS and/or Windows is untested
       and unsupported.

       The random map generator	within Liquid War - which of course  works  on
       any  platform support by	LW - uses for its greater part the same	source
       code as the external lwmapgen program.

       *  random.c / random.h: wrapper for the map generator written by	 David
	  Redick. It basically does the	same as	./utils/lwmapgen/main.c	except
	  that it does it within Liquid	War as it is running  and  not	in  an
	  external independant program.

       Time handling

       Time handling is	fundamental in a game. Time is used for	visual effects
       (waves...) during the game, it's	used to	generate  some	pseudo	random
       stuff, well, it's used everywhere!

       Note  that  on the client, I use	2 "different" clocks. The first	counts
       the "real" time,	in seconds. The	second one is counts "rounds"  and  is
       incremented by 1	at each	game round.

       *  srvtime.c / srvtime.h: code used to handle time on the server, where
	  Allegro's functions are not available.

       *  ticker.c / ticker.h: sets up a timer callback.

       *  time.c / time.h: functions to	know how long the game has  been  run-
	  ning,	knowing	that it	can be interrupted.

       In-game utilities

       These  are  various utilities use to monitor and	control	the game while
       one's playing.

       *  capture.c / capture.h: code used to capture the video	output of  the
	  game and store it in .bmp files while	playing.

       *  checksum.c  /	 checksum.h:  utilities	 to generate a checksum	from a
	  given	game state. Used in network code to make sure all the  clients
	  stay synchronized.

       *  code.c  /  code.h: This file contains	the code to handle key presses
	  during the game. That's to say the pause key for instance.

       *  profile.c / profile.h: provides tools	to calculate how fast the game
	  is runnning and what operations slow it down.

       *  watchdog.c  /	watchdog.h: this module	waits for "secret codes" to be
	  typed	while the game is running, and traps them.

       Command line handling

       OK, now to all the UNIX guys, I *know* there are	many ways to do	things
       in  a  better and simple	way than I did.	But keep in mind that in 1998,
       under DOS, I had	a rotten command line and even now I  need  everything
       to work on both UNIX and	Microsoft platforms.

       These utilities are not perfect,	but they work, that's all I ask	them.

       *  basicopt.c  /	basicopt.h: handles basic command line parameters such
	  as "-v" or "-h".

       *  parser.c / parser.h: contains	code to	parse and analyze the  command
	  line parameters.

       *  startup.c  /	startup.h:  analyzes  the  command line	parameters and
	  stores them into global variables.

       Locale support

       Liquid War now has locale support. Basically, all the labels and	 texts
       in the UI are stored in constants. There's simply file per language.

       Note  to	 translators:  if you decide to	translate the menus in another
       language, keep in mind that all the translations	must fit in the	 vari-
       ous  buttons  and textboxes. The	best resolution	to test	this - the one
       where letters take most place - is 640x480.

       *  lang.c / lang.h: contains code to handle language dependant stuff.

       *  langen.c / langen.h: contains	code to	handle English specific	stuff.

       *  langfr.c / langfr.h: contains	code to	handle French specific stuff.

       Log and various messages

       OK, the API of the log routines is a piece of crap. Now I'm simply  too
       lazy to change it. It works, that's all I ask.

       BTW,  there's  a	 clear	advantage  in  using custom-made log functions
       instead of plain	calls to "fprintf(stderr,...". It might	not be obvious
       for  UNIX  users,  but  think  about  Windows. Nothing like a "tail -f"
       there, nor a proper output redirection system. When a  user  clicks  on
       the  Liquid  War	 icon,	I want "console" information to	be logged in a
       file!

       *  log.h: common	header for logcli.c and	logsrv.c.

       *  logcli.c: contains code to display messages  on  the	console.  It's
	  usefull  for	console	may have different behaviors when the games is
	  used on different platforms.	This  file  is	used  to  compile  the
	  client.

       *  logsrv.c:  contains  code  to	 display messages on the console. This
	  file is used to compile the server, which does not  use  Allegro  at
	  all.

       *  popupgen.h: common header for	popup functions.

       *  popupw32.c: code to handle popup on the Win32	platform. Popups are a
	  must-have under Windows for error  diagnostics,  since  the  average
	  Windows user never gives any look at any log file...

       Macros, utilities and string support

       As usual, I needed to prepare a small set of usefull macros.

       *  macro.h: contains basic wrappers/macros for snprintf like functions.
	  This mostly to ease up string	manipulation which is -	as always -  a
	  nightmare in standard	C.

       *  path.c  /  path.h:  code  used  to  handle  filenames	and paths, for
	  instance remove path and file	extension from a filename.

       It's also important to note that	Liquid War uses	 snprintf  instead  of
       sprintf,	for using the latter is	very likely to cause buffer overflows.
       Under Linux glibc provides this function	but Microsoft does not provide
       it  natively on Windows.	Therefore I used a third party snprintf	imple-
       mentation by Mark  Martinec:  http://www.ijs.si/software/snprintf/  and
       its  source  is available in the	./utils	directory of Liquid War	source
       distribution.

       Byte order and endianess

       As you might know, PC Intel based computers are	"little-endian"	 while
       Sun Sparc stations and Mac computers are	"big-endian". This is an issue
       for LW since in network games maps are transmitted  in  binary  format.
       Therefore I needed to set up some (un)serialization fonctions.

       *  serial.c / serial.h: code used to transform integers and map headers
	  into an uniform cross-platform byte stream which is readable by both
	  little and big endian	machines.

       Thread support

       Liquid  War does	have thread support, but it is a "limited" thread sup-
       port. I mean that the game is generally monothreaded, but a  few	 func-
       tions  use  threads.  For  instance,  calls to the meta-server are done
       within threads.

       Basically, I do not really enjoy	programming in a  multithreaded	 envi-
       ronnement.  So  when  possible,	I  chose the monothread	path, and used
       threads only where I simply would not be	able to	find  another  accept-
       able solution.

       I also needed to	use some mutexes to prevent crashes in the user	inter-
       face.

       *  mutxdos.c: provides fake mutex support under	DOS.  This  module  is
	  here only to make compilation	easier.

       *  mutxgen.h: header for	mutxdos.c, mutxunix.c and mutxw32.c.

       *  mutxunix.c: provides mutex support on	UNIX.

       *  mutxw32.c: provides mutex support on Win32.

       *  thrddos.c:  provides	fake  thread support under DOS.	This module is
	  here only to make compilation	easier.

       *  thrdgen.h: header for	thrddos.c, thrdunix.c and thrdw32.c.

       *  thrdunix.c: provides thread support on UNIX.

       *  thrdw32.c: provides thread support on	Win32.

       Launching external programs

       Liquid War might	sometimes launch external programs. This is (for secu-
       rity reason) not	a default behavior and has to be activated and config-
       ured by yourself, using the "-callback"	command	 line  option  on  the
       server for instance.

       *  execgen.h: header for	execunix.c and execw32.c.

       *  execunix.c: code to launch external programs on UNIX.

       *  execw32.c: code to launch external programs on Win32.

       *  exec2.c: code	to launch external programs within the client, without
	  any interaction with the user, ie no	unwanted  popping  window  for
	  instance.

       Low-level network code

       There  are network packages for Allegro,	but I decided not to use them.
       Socket support is not that hard to implement under UNIX and  Win32  and
       besides,	I've done it for my job	recently, so I just knew how to	do it.

       Another	reason	which  decided me to code my own toolbox is that I did
       not want	Liquid War to have external dependencies - except  Allegro  of
       course.	This  way, UNIX	gamers to not have to set up and/or download a
       specific	network	library. It's also easier to  integrate	 the  game  in
       projects	like Debian if it has few dependencies.

       This network code is not	a masterpiece, it's just a little set of tools
       that have proven	to work. That's	all.

       BTW, it's important to notice that  when	 linking  with	Allegro,  most
       blocking	UNIX calls ("sleep" or "recv" for instance) stop working: they
       alwasys return immediately. This	led me to implement weird ugly	hacks,
       like  calling  "recv"  in a loop	until it gets what it wants... This is
       theorically and practically a performance killer, but I found no	 other
       way  to	fix  this. And FYI, this is not	an Allegro bug,	it's a feature
       8-)

       *  dnsutil.c / dnsutil.h: wrapper code to issue DNS  requests,  without
	  having to handle the hostent struct.

       *  sock2cli.c:  sode  used  to  wrap  low-level network function	on the
	  client.

       *  sock2gen.h: header for sock2cli.c and	sock2srv.c.

       *  sock2srv.c: code used	to wrap	 low-level  network  function  on  the
	  server.

       *  sockdos.c: network API for DOS.

       *  sockex.c: netowrk routines shared by sockunix	and sockw32.

       *  sockgen.h: header for	sockdos.c, sockunix.c and sockw32.c.

       *  sockunix.c: network API for UNIX.

       *  sockw32.c: network API for Win32.

       High-level network code

       These files contains network utilities which are	Liquid War specific.

       *  chat.c  /  chat.h: functions used to handle chat messages in network
	  games.

       *  keyexch.c / keyexch.h: functions to send and	receive	 keys  to  the
	  server. Used on the client.

       *  netconf.c  /	netconf.h:  code to send and receive the config	of the
	  clients over the network.

       *  netkey.c / netkey.h: contains	some tools to manipulate  key  strokes
	  over the network.

       *  netmap.c / netmap.h: code to send and	receive	the maps over the net-
	  work.

       *  netmess.c / netmess.h: contains a parser  to	interpret  plain  text
	  messages. Used when exhanging	information over the network.

       *  netplay.c / netplay.h: contains the code to set up and start network
	  games.

       *  network.c / network.h: contains some network related	functions  and
	  constants used on the	client.

       *  ping.c  /  ping.h:  code  used on the	client to estimate the average
	  ping time with a server.

       *  protocol.c / protocol.h: contains the	sequence of messages send  and
	  recevied by the client when connecting on the	server.

       *  startinf.c  /	 startinf.h:  contains struct and tools	to handle some
	  network informations while starting a	network	game.

       Communication with the meta-server

       The meta-server is called by both client	 and  server.  Basically,  the
       server registers	itself,	and the	client asks for	a list of servers.

       The  meta-server	itself is just a set of	simple PHP scripts with	a sim-
       ple MySQL database. I chose PHP because my provider allows execution of
       PHP pages, that's all.

       The  protocol  is *very*	basic, and uses	HTTP 1.0 for requests. Answers
       are received in plain text, with	one information	per line.  There's  no
       garantee	 that  this  would  work  with any HTTP	server,	but experience
       proved that it works with my provider 8-)

       *  httputil.c  /	 httputil.h:  low  level  functions  to	 handle	  http
	  requests.

       *  wwwcli.c / wwwcli.h: code used on the	client to communicate with the
	  meta-server.

       *  wwwsrv.c / wwwsrv.h: code used on the	server to communicate with the
	  meta-server.

       Server code

       The Liquid War server is	a rather small program.	The only thing it does
       is accept new players, transmit map and game parameters	between	 them,
       and then	"replicate keys".

       By  "replicate  keys" I mean that the server asks each client what keys
       have been pressed during	the  last  round,  and	then  dispatches  this
       informations  to	 all  clients.	This implies that the server has abso-
       lutely no idea of who's loosing,	who's winning, etc...

       All the "logic" of the server is	coded in these files, the rest is only
       utilities and helper functions.

       *  server.c  / server.h:	main code for the server (equivalent of	main.c
	  for the client).

       *  srvchan.c / srvchan.h: code used to handles channels on the  server.
	  A  channel  is associated to a given computer	and may	manage several
	  teams.

       *  srvcont.c / srvcont.h: global	network	controler used on the server.

       *  srvteam.c / srvteam.h: code used to handle teams on the server.

Bugs
   Report a new	bug
       If you have troubles with Liquid	War 5, if you think it is a  bug,  and
       if  it  is  not	described  in this file, then just send	a (precise...)
       decription of your problem to the Liquid	War user mailing list.

       Besides,	it happens that	now most bug  reports  come  from  the	Debian
       tracking	 system	"http://bugs.debian.org/cgi-bin/pkgreport.cgi?pkg=liq-
       uidwar".	Thanks to the Debian users and maintainers, it's a very	 valu-
       able feedback source.

       Additionnaly,  on  online  bug tracking system has been set up. It uses
       Flyspray	    http://flyspray.rocks.cc/.	   It's	    accessible	    on
       http://www.ufoot.org/bugtracker/	     or	    "http://www.ufoot.org/bug-
       tracker/index.php?project=2". I try to collect everything here  :  bugs
       reported	 on  the  mailing-list,	 bugs  from  Debian,  and bugs I found
       myself. Alternatively you can report bugs directly on it	8-)

   Network
       Network support in Liquid War is	far from being perfect,	so there are a
       bunch  of little	problems which can appear. Basically, once the game is
       correctly started on a LAN, you should have no  problems,  but  getting
       the game	started	might be difficult.

   Mouse does not work
       Some  users  reported  that  they were unable to	control	the Liquid War
       cursor with the mouse. Well, the	answer is a typical Microsoftish "this
       ain't a bug, it's a feature!".

       More seriously, you're supposed to move the cursor with the keyboard in
       Liquid War. There's no way to handle the	cursor "like a mouse  pointer"
       (*). This is due	to:

       *  Severe limitations in	the Liquid War core algorithm.

       *  The  fact  that moving the cursor "too fast" would really change the
	  gameplay of Liquid War. As a Liquid War integrist 8-)	I can tell you
	  the  game  would really not be the same if you could move the	cursor
	  as fast as you wish. It's part of the	game that sometimes  it	 takes
	  you  ages  to	recover	from a strategical mistakes. You need to think
	  twice	before going to	the very end of	a level. That's	 strategy.  At
	  least	 that's	 how  I	 view  things... Anyways as I mentionned above
	  there's a limitation in the core algorithm.

       (*) This	is not perfectly true, there's a way  to  control  the	cursor
       with  the  mouse, but it's designed for the case	"4 people want to play
       on the same computer and	one single keyboard is not  enough".  Control-
       ling the	cursor with the	mouse in Liquid	War is possible	but yet	rather
       hard to master 8-/ Try it and you'll understand what I mean. This  mode
       can be set up in	the "Teams" menu.

   Game	does not start
       On non UNIX platforms such as Windows or	DOS, Liquid War	is distributed
       in a .zip file. It's IMPORTANT that you unzip the .zip  files  with  an
       "unzipper"  which preserves the directory structure. Most install prob-
       lems under Windows come from broken unzipping  programs	which  extract
       all  files in the same directory... WinZip 8.x or the unzip32.exe util-
       ity that	comes with DJGPP are both able to uncompress Liquid  War  .zip
       files correctly.

       On  Liquid  War 5.5.9 and later,	the Windows version should detect this
       problem automatically and warn you with a message which basically  says
       something  like	"Unable	 to  load datafile. Are	you sure Liquid	War is
       correctly installed?". If you get this message, you need	 to  reinstall
       the  game by unzipping it with a	"correct" unzipping program which does
       not wreck directory structrure up.

   Interference	with other Windows programs
       It's been reported that Liquid War can run very slowly on Windows  when
       some  other  programs  (Mozilla for instance) are running. So if	Liquid
       War's menus seem	to be really really slow, then try to shut down	 other
       applications and	run the	game again.

       This  problem  does not seem to apply on	GNU/Linux - at least if	you do
       not run 300 daemons together on your machine 8-)

   Datafile bugs
       Sometimes there are some	problems when  compiling  the  datafile,  this
       includes:

       *  The  liquidwarcol,  liquidwarmap  and	 liquidwartex  utilities might
	  freeze or segfault. Typing "make" again often	solves the problem.

       *  The background image sometimes ends  up  using  the  wrong  palette,
	  which	has a very nasty consequence: it looks ugly.

       These  bugs  are	 quite	hard to	get rid	off, since I can not reproduce
       them easily. The	good solution would be to completely rewrite the  liq-
       uidwarcol, liquidwarmap and liquidwartex	utilities.

   Midi	does not work on OSS
       Preamble

       IF  your	 midi  music  on Liquid	War, or	indeed any other Allegro game,
       doesn't work and	you are	using the  OSS	(Open  Sound  System)  drivers
       (these  are  the	sound drivers which come with the standard kernel dis-
       tribution), this	may well be because Allegro only supports "FM  synthe-
       sis"  and  not "wavetable" when it is using OSS.	FM synthesis is	a very
       old method of making sound from MIDI and	has long since	been  replaced
       by  wavetable  synthesis,  with the net result that it's	quite possible
       you've got OSS MIDI working nicely in other applications	without	having
       FM support set up at all. This is what I	found. (It has to be said that
       I didn't	find the FM sound quality quite	as bad as  people  have	 said,
       though).

       In this situation, it looks to me like you have the following choices:

       Hack Allegro...

       and for the rest	of us...

       Use Allegro's DIGMID midi driver...

       Get an FM driver	up and running...

       *  Find	out which FM driver is appropriate for your sound card.	If you
	  have distribution-specific tools and docs for	setting	up sound,  try
	  those.  If  not,  you	will need to be	familiar with the knowledge in
	  the Sound-HOWTO and Kernel-HOWTO i.e.	know how  to  compile  kernels
	  and modules and deal with sound drivers.

       *  Look	through	 the  OSS modules in 'make menuconfig' and see if any-
	  thing	catches	your eye. See if there is any  specific	 documentation
	  on  your  sound  card	 on  http://www.linuxdoc.org.  Do  a  few  web
	  searches. For	my AWE64, I use	the OPL3 driver.

       *  Compile and install the FM driver module, or set up your  system  to
	  use the new kernel if	you want to compile the	driver in.

       *  Load	the module, or boot your new kernel. It	is very	important that
	  you pay attention to what is said in the 'help' for your  FM	driver
	  in  'make menuconfig'	and read any necessary files in	the Documenta-
	  tion/sound/ directory. For example, I	just had a nice	half-hour won-
	  dering why the hell my FM wasn't working now when it had been	before
	  - with the OPL3 driver, you have to give the option io=0x388 to ins-
	  mod. Which is	stated nice and	clear in the docs, but of course I had
	  forgotten since then.	You can	prevent	such happenings	 by  recording
	  options permanently in /etc/modules.conf - see the manpage etc.

       *  Try the game.	If it's	worked you will	hear particularly beepy	music.
	  Enjoy!

       Opl3 occult FAQ

       --IMPORTANT-- If	you are	using Liquid War, your FM will	only  work  if
       you  go	to  the	 map 'Elephant inside a	boa' and proceed to chase each
       other round in circles for at least 10 minutes. This cures a bug	in the
       design of the OPL3 interface which conflicts badly with the core	Liquid
       War algorithms. How the hell the	music hardware even  knows  about  the
       core algorithms I don't know, but that's	what I made of the now-defunct
       opl3-occult-FAQ,	from which here	is an excerpt:

       Many roads a man	must take. Those with one-track	minds  are  DOOMED,  I
       tells ya.

       ----  The  Liquid  War algorithm	calculates distances to	one place, the
       cursor.

       And:

       Man or machine, face or code, must stand	strong	and  solid;  must  not
       just ooze away as slime.

       ----  We	think it might just take objection to the whole	'slimy'	nature
       of the LW beings. As well as it being LIQUID War.

       So, our carefully tailored approach, is to  firstly  have  the  players
       going  in all the possible different directions evenly by moving	around
       the map in circles, and secondly	to divert the  opl3's  attention  from
       the  general  slimy  liquidness	of it all by emphasizing the solidity,
       reality,	and natural goodness of	that  classic  tapestry:  an  elephant
       inside a	boa.

       That and	it's a f***ing ace level.

   Checksum errors
       The Liquid War server is	a "light" servers which	- to some extent - has
       no idea about what is going on in the game. It  simply  replicates  key
       strokes	between	 clients and each client maintains its own game	state.
       Normally, the game is designed so that given the	same  user  input,  it
       will behave exactly the same.

       However,	 it  happens  that sometimes 2 clients can behave differently,
       and this	is a (severe) bug. One consequence is that messages  reporting
       "Checksum  errors"  appear  on the server's and on the client's console
       output. This bug	appears	when using non-default rules  settings.	 Basi-
       cally,  if  someones tweaks his rules, then the checksum	errors appear.
       Of course I double-triple checked that options were correctly  sent  on
       the  network,  but,  well,  could  not fix the bug. Yet.	The short term
       solution	seems to play with default factory settings...

       I'm highly interested in	bug-reports concerning this problem.

To do
   Bug-fixing
       In its latest releases Liquid War is quite stable IMHO.	However	 there
       are  still  some	 issues	 with  network under Windows for instance. I'm
       aware of	these bugs and I'm trying to fix them  but  this  does	really
       take time.

       I  always welcome bug-reports and patches, as making Liquid War W 5.x.x
       as stable and bug-free as possible is really important to me - and most
       of the time players also	appreciate stable programs 8-)

       The  most important bug-fixing area is probably cross-platform support.
       That is,	make sure that the game	runs fine on every supported  OS.  For
       instance,  it's	quite  common  for  Mac	 OS/X  and/or FreeBSD users to
       "crash" the game. This rarely happens on	GNU/Linux, just	because	it has
       been  so	 much more tested on this platform. This applies to Liquid War
       itself and also,	to some	extent,	to Allegro.

   New features
       Let's be	clear: no new features in Liquid War 5.	It's bloated,  compli-
       cated,  old, uninteresting to hack. All new features should be found in
       Liquid War 6.

   Liquid War 6
       Since summer 2005, Liquid War 6,	a complete rewrite of Liquid  War,  is
       on    its    way.    See	  http://www.gnu.org/software/liquidwar6/   or
       http://www.ufoot.org/liquidwar/v6 for more informations.

Work in	progress
   Note	on releases
       Whenever	Liquid War is released,	I usually pass the good	news to	Fresh-
       meat  (	http://freshmeat.net/projects/liquidwar/  ). Then all releases
       are   accessible	  from	 the   main   download	  page,	   which    is
       http://www.ufoot.org/liquidwar/v5/download.

       Releasing the game takes	time, for I want all binaries to install prop-
       erly and	sources	to compile cleanly.  Therefore	there  might  be  some
       delay before the	time coding is over and	the time a release is actually
       ready. So for impatients	and/or for people who need  to	test  out  the
       very latest versions (eg	someone	who wants to compile the game on a new
       platform), it's possible	to access the source repository	directly.

   About GNU Arch
       I use GNU Arch  (Tom  Lord's  Arch  in  fact,  http://www.gnu.org/soft-
       ware/gnu-arch/  )  instead  of the previously used CVS. Indeed, tla has
       some very fancy features	such as	signing	 patches  with	gpg,  and  I'm
       tired of	suffering CVS limitations.

       So  FYI	the  previously	 active	 CVS  repositories, on Sourceforge and
       Savannah, are currently unmaintained.

   How to get latest releases
       *  Step	 1:   read   the   excellent   Arch    tutorial	   http://reg-
	  exps.srparish.net/www/tutorial/html/arch.html	 if you	are not	famil-
	  iar with tla.	I admit	there's	a steep	learning curve,	but  it's  yet
	  clear	and understandable.

       *  Step	2: point on the	repository, which is accessible	(read-only) on
	  http://arch.sv.gnu.org/archives/liquidwar/.

       A typical set of	tla commands would be:

       tla register-archive http://arch.sv.gnu.org/archives/liquidwar
       tla get -A liquidwar@sv.gnu.org liquidwar6--stable

       If you are interested, I	can open this repository in  read/write	 mode,
       however	one  of	 the  points of	GNU Arch is that it allows cooperative
       developpement with multiple depots, so this isn't mandatory.  And  any-
       ways,  importing	myself patches received	by email has never been	a real
       burden.

       Besides,	 most  developpement  is  now  done  on	 Liquid	 War  6.   See
       http://www.gnu.org/software/liquidwar6/ or http://www.ufoot.org/liquid-
       war/v6 for more informations.

Copying
       Liquid War is a multiplayer wargame.

       Copyright (C) 1998-2007 Christian Mauduit (ufoot@ufoot.org)

       This program is free software; you can redistribute it and/or modify it
       under  the  terms of the	GNU General Public License as published	by the
       Free Software Foundation; either	version	2 of the License, or (at  your
       option) any later version.

       This  program  is  distributed  in the hope that	it will	be useful, but
       WITHOUT ANY  WARRANTY;  without	even  the  implied  warranty  of  MER-
       CHANTABILITY  or	 FITNESS FOR A partICULAR PURPOSE. See the GNU General
       Public License for more details.

       You should have received	a copy of the GNU General Public License along
       with this program; if not, write	to the Free Software Foundation, Inc.,
       51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA

AUTHOR
       Christian Mauduit <ufoot@ufoot.org>

				    v5.6.4			 Liquid	War(6)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | WARNING | Rules | Authors | Mailing lists | Fanfic | Menus and hot keys | Network game | Command line parameters | Platform specific issues | User levels | Core algorithm | Source code | Bugs | To do | Work in progress | Copying | AUTHOR

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