Trax FAQ From: D.G.Bailey@massey.ac.nz (Donald G Bailey) Date: Sun, 18 Sep 1994 21:11:51 +0000 ======================================================================== TRAX: Answers to common questions. ======================================================================== This FAQ is copyright 1994 by Donald Bailey. The rules are copyright by David Smith, and are used here with permission. Any suggestions, questions, or comments should be sent to Donald Bailey: D.G.Bailey@massey.ac.nz ======================================================================== CONTENTS: A: INTRODUCTION A1) Where can I get this FAQ? A2) What is Trax? A3) What is required to play Trax? A4) Where can I obtain a set? A5) What is the history of Trax? B: RULES B1) How is Trax played? B2) What is Supertrax? B3) What happens if we both win on the same move? B4) Why do the rules require that you extend currently existing loops? B5) What happens if different fill algorithms generate different boards? B6) What is the precise definition of a "line" for win purposes? B7) Which 8x8 counts for line wins? B8) Is there a complete set of rules available online? C: DEFINITIONS C1) What is a "loop attack"? C2) What is a "corner"? C3) What is a "connectable pair"? C4) What is a "cave"? C5) What is a "L threat"? C6) What is a "edge threat"? D: NOTATION D1) How do I record a game (other than drawing the position each turn)? D2) Is there a convenient ASCII representation of a position? D3) What do you do if the game area is wider than 26 ('Z') ? E: STRATEGY E1) Which is more important, loops or lines? E2) How can I tell who has the best position? E3) If I don't know what to do, what is wrong with attacking? E4) When should I attack? E5) When should I start worrying about my opponent's lines? E6) What are the typical stages of a Trax game? E7) What is the strategic significance of caves? E8) Are there any general principles for how to play well? E9) How can I find out more about Trax strategy? F: ORGANISATIONS F1) rec.games.abstract archives F2) Trax server F3) Mailing list F4) Clubs ACKNOWLEDGEMENTS ======================================================================== A: INTRODUCTION ------------------------------------------------------------------------ A1) Where can I get this FAQ? This FAQ will be posted to rec.games.abstract whenever a call for participation in a tournament is made to r.g.a. It is also available by sending an electronic mail message to pbmserv@netcom.com with help trax.faq in the subject line. You will then be sent this FAQ by return e-mail. It is also available on WWW from http://www.comp.vuw.ac.nz/~michael/games/trax/ ------------------------------------------------------------------------ A2) What is Trax? Trax is a strategy game for two players, that relies on pure skill. It is played with a set of identical tiles with sections of black and white track on them. Players take turns at playing the tiles, with the purpose of completing either a closed loop of their colour or continuous path from one side to the other of the playing area (either horizontally or vertically). While Trax is a simple game to learn, there is plenty of scope for strategic play. Like many other strategy games, Trax can be played at a range of levels. Learning to play Trax is one thing, learning to play well is another. That is why Trax has often been called "The game for those who love a challenge!" ------------------------------------------------------------------------ A2) What is required to play Trax? _____________ _____________ | | | | | | | | | | | | | / / | | | | | |___/ / | |#############| |____/ ####| | | | | | #### | | | | | | ## | |_____|_|_____| |_____##______| Trax is a game played with a set of 64 identical tiles. These tiles have white and black straight sections on one side and white and black curved sections on the other. The most common form of tiles is red plastic measuring 31.5 mm square, 6.4 mm thick. The black and white paths are painted in recesses 5.5 mm wide. In addition to the tiles, all you need is a flat surface on which to play. ------------------------------------------------------------------------ A3) Where can I obtain a set? Sets have been published in many countries around the world, in a variety of styles of packaging. If you are unable to find a set in your area, they are available via mail order from the New Zealand Trax Association (contact D.G.Bailey@massey.ac.nz) or in the United States from the Bay Area Trax Club (contact mel@csua.berkeley.edu). ------------------------------------------------------------------------ A4) What is the history of Trax? Trax was invented in New Zealand in 1980 by David Smith. It was first published in New Zealand and the United States in 1982. It is now published and played virtually worldwide. The first club was the Canterbury Trax Club formed in 1985 in Christchurch NZ. Trax was a Games 100 game from 1982 to 1986, and won the Parents' Choice Magazine's Gold Seal Award in 1987. ======================================================================== B: RULES Note: as Trax is a proprietry game these rules are copyright by David Smith. They have been reproduced here with permission. ------------------------------------------------------------------------ B1) How is Trax played? 1 Two players decide who shall be white and who shall be black. 2 White always plays first (there is no advantage). 3 Each player in turn plays one tile either side up, adjacent to any already played tile such that the colours match. eg +--o--+ +--o--+ +--o--+--o--+ | o | | o | | o | o | oo ## <= ###o### giving oo ####o### | # | | o | | # | o | +--#--+ +--o--+ +--#--+--o--+ 4 Each player may join track of either or both colours at any turn. 5 If any played tile results in an adjacent space or spaces that has two tracks of the same colour entering it a `forced' tile is played so as to join the two tracks together. If this tile creates other spaces with two tracks of the same colour entering, then further forced tiles are played. eg playing this forces this then this giving this +--o--+ +--#--+ +--o--+--#--+ +--o--+--#--+ +--o--+--#--+ | o | | # | | o | # | | o | # | | o | # | ## oo<oo ## ## ooo ## ## ooo ## ## ooo ## | # | | o | | # | o | | # | o | | # | o | +--#--+ +--o--+ +--#--+--o--+ +--#--+--o--+ +--#--+--o--+ | # | | # | +--o--+ | # | o | | # | o | ooooooo ooooooo | o | oooooooo ## oooooooo ## | # | | # | oo ## | # | # | | # | # | +--#--+ +--#--+ | # | +--#--+--#--+ +--#--+--#--+ | # | | # | +--#--+ | # | +--#--+ | # | # | oo ## oo ## oo ##| # | oo ### oo | o | | o | | o | ## oo | o | o | +--o--+ +--o--+ +--o--+ | o | +--o--+--o--+ +--o--+ The player's turn ends when all forced tiles have been played. 6 Missed forced moves should be played as soon as noticed, at no penalty to either player. 7 If a tile or forced tile is played that results in a space with three or four tracks of the same colour entering, the move is illegal and must be taken back and replayed (at no penalty). 8 The winner is the player whose track first forms a LOOP or a LINE. 9 A loop is any path of track that connects to itself, whatever its shape. +--#--+--#--+--#--+ | # | # | # | ## ooooooooo ## | o | # | o | A white loop: +--o--+--#--+--o--+ | o | # | o | ## ooooooooo ## | # | # | # | +--#--+--#--+--#--+ 10 A line is a continuous path that connects opposite and outermost edges of the layout, at least 8 rows of tile across or down. +--#--+--#--+--#--+--o--+--#--+ | # | # | # | o | # | ## ooooooooo ### oooooooo | o | # | o | # | # | +--o--+--o--+--#--+--o--+--#--+--#--+--#--+ | o | o | # | o | # | # | # | A horizontal white line: oo ### ooo ### oooooooooooooooooooo | # | # | o | # | # | # | # | +--#--+--#--+--#--+--o--+--#--+--#--+--#--+--#--+ | # | # | # | o | # | oooooooooooooooooooo ### oo | # | # | # | # | o | +--#--+--#--+--#--+--#--+--o--+ 11 If a loop or a line is formed by both colours during either players turn, the game is won by that player. 12 The playing area may not be extended beyond 8 rows wide and 8 rows deep (Regular Trax). 13 If a win is not achieved after all 64 tiles have been played, the result is a draw. ------------------------------------------------------------------------ B2) What is Supertrax? Supertrax is a variation of Trax played in tournaments. It is played with no size limits, so the game continues until one player or the other wins. No draws are permitted. (Rules 12 and 13 above are cancelled). ------------------------------------------------------------------------ B3) What happens if we both win on the same move? This is a win for the player who made the move (see rule 11 in B2). There was a rule change since the early sets were printed. In Supertrax there have never been any draws, since it was decided that this would give it a considerable advantage over games such as chess and the like, hence the arbitrary decision of making it a win for the player who played. Supertrax was not played seriously until late 1986 when it was first used for the finals of the inaugural World Championship. After that, there has been a gradual move away from regular Trax to Supertrax as the game played by serious players. However the discrepancy in the rules between the two games over simultaneous wins was confusing at first for players who 'graduated' to Supertrax. It was therefore decided to make the two games more consistent by making the minor rule change to Trax to simplify the process of moving from one game to the other. ------------------------------------------------------------------------ B4) Why do the rules require that you extend currently existing paths? (See rule 3 in B2). Playing the tiles in arbitrary positions causes the game to degenerate. For example if there is a curved tile, it is possible to force a loop in a single turn by playing diagonally off the corner. This gives two forced tiles which close the loop. Playing this would result in this +--#--+ +--#--+--#--+ | # | | # | # | ## oo ## ooo ## | o | | o | o | +--o--+--o--+ +--o--+--o--+ | o | | o | o | oo ## ## ooo ## | # | | # | # | +--#--+ +--#--+--#--+ ------------------------------------------------------------------------ B5) What do you do if different fill algorithms generate different boards? This does not happen. It can be shown that the pattern of forced tiles played in a legal move is unique, so it doesn't matter what order that the forced tiles are placed. A move is illegal if it results in a position where there are 3 or 4 lines of the same colour going into an empty space. Such moves will allways be illegal, regardless of the order in which the forced tiles are played. An illegal move must be taken back and an alternative move played (see rule 7 in B2). ------------------------------------------------------------------------ B6) What is the precise definition of a "line" for win purposes? A line is a single path of track that joins the outermost opposite edges of the playing area across at least 8 rows or columns. The line does not have be a straight path, it may be as convoluted as you like, as long as it reaches the outermost opposite edges of the playing area. The two ends of the line do not even need to be directly opposite, as long as they come out somewhere on the opposite sides. In other words one end of a horizontal line must come out on the left hand side of the leftmost tile in the playing area, and the other end must come out on the right hand side of the rightmost tile in the playing area. Similarly for vertical lines. (See rule 10 in B2). ------------------------------------------------------------------------ B7) Which 8x8 counts for line wins? In regular Trax, the final position of the 8x8 playing area depends on where the tiles are played. It is defined as the 8th row or 8th column is added, limiting the playing area in that direction. With Supertrax, it is not the 8x8 that is important, but that the line reaches the outermost edges of the playing area spanning at least 8 rows or columns. See question B6. ------------------------------------------------------------------------ B8) Is there a complete set of rules available online? Rules are available on the rec.games.abstract anonymous FTP archive (pprg.eece.unm.edu [129.24.24.10]) in the pub/rec.games.abstract/games/trax/ directory. This FAQ is also available by sending e-mail to pbmserv@netcom.com with help trax.faq in the subject line. ======================================================================== C: DEFINITIONS ------------------------------------------------------------------------ C1) What is a "loop attack"? A loop attack is any path which may be made into a loop in a single turn. An attack by your opponent must be defended immediately, otherwise you will lose the game. There are two sorts of loop attacks: +--o--+--o--+ +--o--+--#--+--o--+ | o | o | | o | # | o | narrow ## ooo ## and wide ## ooooooooo ## | # | # | | # | # | # | +--#--+--#--+ +--#--+--#--+--#--+ The narrow loop attack is closed by turning either end of the attack toward the other. The wide attack is closed by playig a straight in the centre. ------------------------------------------------------------------------ C2) What is a "corner"? A corner is any single path that may be formed into a loop attack in a single turn. The simplest type of corner is a single curve. Corners are important in Trax because they represent attacking potential. Examples of white corners: +--o--+--#--+ +--o--+--#--+--#--+--#--+--o--+ | o | # | | o | # | # | # | o | ## oooooooo ## ooooooooooooooooooooo ## | # | # | | # | # | # | # | # | +--#--+--#--+ +--#--+--#--+--#--+--#--+--#--+ Note that a corner can be made into an attack in two ways, by turning either end around toward the other. ------------------------------------------------------------------------ C3) What is a "connectable pair"? A connectable pair is a pair of adjacent paths, which when linked at either end, will result in a loop attack at the other end. Connectable pairs and corners are of similar importance in terms of potential. +--o--+--#--+--o--+ | o | # | o | A white connectable pair: ## ooo ####o### | # | o | o | +--#--+--o--+--o--+ ------------------------------------------------------------------------ C4) What is a "cave"? A cave is an empty region of the playing area which has tile on three or four sides. An example of a cave: +--#--+ +--#--+ | # | | # | ## oo oo ## | o | | o | +--o--+--#--+--#--+--o--+ | o | # | # | o | oo ### ooooooooo ## | # | o | # | # | +--#--+--o--+--#--+--#--+ ------------------------------------------------------------------------ C5) What is an "L threat"? An L is a special case of a 2-stage threat where 2 simultaneous attacks may be made by playing into an L shaped region. The simplest L is as follows: +--o--+ | o | oo ## | # | +--o--+--#--+--#--+ | o | # | # | oo ### oooooooo | # | o | # | +--#--+--o--+--#--+ ------------------------------------------------------------------------ C6) What is a "edge threat"? An edge threat is a special case of a 3-stage threat where a loop attack can be made at one end of the edge at the same time as forming an L threat at the other end. Since the other player must defend the attack, on the next turn the attacking player can use the L. The basic edge threat is: +--o--+--#--+--#--+--o--+ | o | # | # | o | oo ### ### oo | # # | +-- --+ ======================================================================== D: NOTATION ------------------------------------------------------------------------ D1) How do I record a game (other than drawing the position each turn)? An algebraic coding scheme has been devised to record each turn. The game is recorded as viewed by white. Three symbols are used to record the first tile played in any turn. Forced tiles do not need to be recorded as these are self evident. 1: A letter is used to denote the column played reading left to right AFTER the tile is played. 2: A number is used to denote the row played reading top to bottom AFTER the tile is played. 3: The third symbol is a letter indicates the tile played: S is used whenever straights are played C is used whenever curves is played as the first tile or against 2 edges otherwise U, D, L or R are used when the track extended is turned up, down, left or right respectively. In the rare circumstance when a curve is played across the mouth of a cave and the symbol C is ambiguous, the direction that the white track is extended should be specified. The order of the first two symbols is reversed to distinguish a tile played ABOVE rather than TO THE LEFT of the top left corner. 1A ,--. A1 | | B1 `--' A2 For notational purposes, the first tile must be played with the while line vertical (if straights) or between the top and left corners (if curves) ie +--o--+ +--o--+ | o | | o | either ###o### or oo ## | o | | # | +--o--+ +--#--+ ------------------------------------------------------------------------ D2) Is there a convenient ASCII representation of a position? The representation used so far in the FAQ is one possible representation allowing the position to be seen reasonably clearly. However, for large games, or for manually entering a position, this notation is a little cumbersome. A more compact representation in common use is: . o . . o . . o . x . Two tiles straights x x curves o / x x \ o o side by side . o . . x . . x . x . where the white path is represented by o and the black by x. Note that this representation is not as clear, particularly for larger positions. It can be made clearer if printed out and the two sets of paths drawn over in different coloured pens. ------------------------------------------------------------------------ D3) What do you do if the game area is wider than 26 ('Z')? The columns are labelled A B C ... Y Z AA AB AC ... AZ BA etc In practise, the largest I have seen for a real game was somewhere around S or T ======================================================================== E: STRATEGY ------------------------------------------------------------------------ E1) Which is more important, loops or lines? They are both equally important. Trax is all about a balance in between the two. Defending loops tends to straighten them into lines, while defending lines tends to bend them into loops. This said, loops are faster to make since any corner can be made into an attack. They are also easier to defend (usually). Lines take several turns to build, and are more obviously threatening because you can see them grow. They are also harder to defend, often requiring several turns. ------------------------------------------------------------------------ E2) How can I tell who has the best position? This is a difficult question. The most straight forward approach is to look at attacking potential. The number of corners and connectable pairs that a player has gives an indication of the attacking potential of that player. Corners and connectable pairs form part of more complex multiple stage threats such as Ls and edges (see C5 and C6). If there are strong line possibilities, then these should be counted as well. Note that the approach of counting corners does not take into account their position relative to the rest of the playing area. It is possible to have only a single corner and be able to win the game, or have many corners yet have a relatively weak position. The strength of a position also depends on who has the initiative. A more detailed analysis is beyond the scope here. Having said this, corner counting does provide a useful FIRST ESTIMATE of the strength of a position. ------------------------------------------------------------------------ E3) If I don't know what to do, what is wrong with attacking? This is one of the most common strategic errors of new Trax players. Corners represent attacking potential. However, by making an attack prematurely, you actually weaken your position. The reason for this is twofold. First, when you attack, you use up a corner, reducing your potential. Second, when your opponent defends, they can usually do so in a way that gains them a corner. So, in general, you not only weaken your own position, but also strengthen your opponent. If you don't know what to do, DON'T attack. Kill one of your opponent's corners instead. ------------------------------------------------------------------------ E4) When should I attack? Given that attacking without purpose more often than not harms a position, the best time to attack is when it helps the position. There are three circumstances where this is the case: 1) When you can force a win. 2) When your opponent has several independent threats (which cannot be defused simultaneously). 3) If after the attack or attack sequence is over, your position has improved regardless of what defences your opponent makes. Care needs to be taken with case 1 since it is very easy to overlook a counterattack, which can be fatal. If there are corners around that will cause counterattack problems, it is usually better to defend the potential counterattacks before starting the attack sequence. ------------------------------------------------------------------------ E5) When should I start worrying about my opponent's lines? There is no easy answer to this. Probably as soon as you recognise them! Lines can be a problem from about 3 tiles long if that is all there is. ie if the playing area is only 3 tiles wide and the line is the same length, it could easily become a serious threat. Also, segments which are on their own on one side of the playing area (without any other lines of the same colour) can also be dangerous since they can easily grow very quickly. Some hints for defending lines: 1) Start early! A line threat can take several turns to defend properly. 2) Turn lines toward your own corners to slow them down. 3) The best way of defending a line is to link it back to a parallel path. 4) Be careful when turning a line back that you don't give your opponent a loop threat. ------------------------------------------------------------------------ E6) What are the typical stages of a Trax game? A typical game goes through at least three stages: 1) the opening, where players are jostling for initial advantage. Any mistakes at this stage usually result in loop wins. 2) the growing stage, as the position approaches and passes through the 8x8 threshold. Often lines, if there are any present, can become critical during this stage. Losses here can be either loops or lines. 3) after the position becomes much bigger, line threats usually lose their significance, and loop threats tend to predominate. As the position gets larger it tends to become more and more unstable, until one player gradually loses the advantage and loses. ------------------------------------------------------------------------ E7) What is the strategic significance of caves? Playing in caves generally results in more forced moves than playing elsewhere on the playing area. This can make it harder to see what is going to happen as a result of the move. This is made worse by some moves in caves being illegal. For these reasons, most players do not like caves and tend to fill them at the earliest opportunity. However, in spite of their difficulties, caves have two aspects that make them important. Certain attacks into caves are not able to be defended. Therefore cave attacks provide an alternative to Ls and other multiple loop threats for forcing a win. The second significance of caves is that it is possible to have caves in which there are no legal moves. Such "dead" caves can provide an extremely strong defensive element since any lines entering the cave can no longer be used in a win as they cannot be joined. Lines and loop threats may be defended permanently by linking them to a path going into a dead cave. ------------------------------------------------------------------------ E8) Are there any general principles for how to play well? Detailed long term strategies are very hard to form. Most threats tend to be fairly localised so the game tends to progress from one hot spot to another. Trax is more of a waiting game - playing for long term advantage in terms of potential, while seizing whatever opportunities your opponent gives you. Several general principles that I have found helpful: 1) Killing your opponent's corners, replacing them with your own. 2) Keep your options open. If a path can be used for either a loop or a line, don't commit it either way. Work on something else and wait for your opponent to make the move for you. That way you gain a turn. 3) Do not make pointless attacks or even pointless Ls. You lose attacking potential when your opponent defends them. 4) Where possible, try to make your move do more than one thing. Don't just defend, but defend and set up a threat for yourself at the same time. 5) Play in such a way as to limit the number of safe moves your opponent has. Your opponent is then more likely to make a mistake and give you the game. 6) Use sacrifice to good advantage. If you can set up something obvious (such as an L or an edge (see C5 and C6)) at the same time as setting up something more subtle, most players will see the obvious threat, and fall for the subtle. In other words you can sacrifice some corners or even a strong line to improve your overall position. ------------------------------------------------------------------------ E9) How can I find out more about Trax strategy? An excellent introduction to Trax strategy can be found in "Trax Strategy for Beginners", by Donald G Bailey. Published by D.G. Bailey, 1 Salisbury Ave, Palmerston North, New Zealand. (1992) ISBN 0-473-01592-7 If you are at all serious about playing Trax then you should get this book. Contact D.G.Bailey@massey.ac.nz Highly recommended. ======================================================================== F: ORGANISATIONS ------------------------------------------------------------------------ F1) rec.games.abstract archives Annotated game logs, and a description of the game are available on the rec.games.abstract anonymous FTP archive (pprg.eece.unm.edu [129.24.24.10]) in pub/rec.games.abstract/games/trax/ ------------------------------------------------------------------------ F2) Trax server Two automated e-mail servers have been set up to handle trax games: Server Contact Address for problems munch@soda.berkeley.edu Mel Nicholson mel@csua.berkeley.edu pbmserv@netcom.com Richard Rognlie rrognlie@netcom.com Send a mail message to either server with 'help' in the subject line to get information on how to use that server. Note that all messages must be sent in the subject line. Anything in the main body is ignored. ------------------------------------------------------------------------ F3) Mailing list There is a mailing list, used to broadcast challenges, announcements, etc relating to Trax. So sign onto the mailing list, e-mail the following message to majordomo@massey.ac.nz subscribe trax Note that all text to listserv must be in the body, the subject is ignored. To get a list of other commands, send the message help To get a list of recipients on the trax mailing list, sent the message who trax To broadcast a message on the mailing list, e-mail the message to trax@massey.ac.nz. It you have difficulty with the server, send e-mail describing your problem to T.Siegenthaler@massey.ac.nz. ------------------------------------------------------------------------ F4) Clubs Known Trax clubs and contacts: Canterbury Trax Club David Smith, 37 Bannister Place, Christchurch, NZ Manawatu Trax Club Tom Siegenthaler: T.Siegenthaler@massey.ac.nz Bay Area Trax Club Mel Nicholson: mel@soda.berkeley.edu Wellington Region Michael Norrish: Michael.Norrish@comp.vuw.ac.nz The New Zealand Trax Association is an association of Trax clubs and individuals within New Zealand. The NZTA publishes a newsletter which comes out about three or four times a year. NZTA contact is D.G.Bailey@massey.ac.nz ------------------------------------------------------------------------ F5) Tournaments Many of the clubs listed above have annual tournaments. Tournaments are also held on the Trax server from time to time. Most of the open tournaments are announced on the Trax mailing list and where applicable, in the rec.games.abstract and rec.games.pbm newsgroups. The world Trax championship is held every two years on even years. This consists of a series of regional qualifier tournaments, the winners of which proceed to the Candidate's tournament. The winner of the Candidate's tournament challenges the incumbent champion in the Challenge Match. ======================================================================== ACKNOWLEDGEMENTS: Particular thanks go to David Smith, the inventor and owner of the rights of Trax, for his permission to include the rules, and support for the FAQ. Many thanks to the subscribers of trax@massey.ac.nz for their questions, without which we wouldn't have a FAQ sheet, and for their helpful suggestions regarding the arrangement of material presented here. Up