https://www.hexwiki.net/index.php?title=Special:NewPages&feed=atom&hideredirs=1&limit=50&offset=&namespace=0&username=&tagfilter=HexWiki - New pages [en]2021-03-07T06:57:02ZFrom HexWikiMediaWiki 1.23.15https://www.hexwiki.net/index.php/TidinessTidiness2020-12-28T18:32:32Z<p>Selinger: Added category</p>
<hr />
<div>'''Tidiness''' means not leaving loose ends that could benefit the opponent later. It is not a reaction to a specific imminent threat, but a basic preventative measure that decreases the likelihood of bad things happening in the future. If a player can make a move that carries little cost or risk, but takes away some opportunity from the opponent, it is ''untidy'' not to make the move. Making such a move is also called ''tidying up''.<br />
<br />
== Examples ==<br />
<br />
=== Acute corner example ===<br />
<br />
Consider the following situation, where Red has just played 1 to connect her group to the bottom edge.<br />
<hexboard size="4x5"<br />
coords="none"<br />
edges="bottom right"<br />
contents="B c2 R d1 1:d2"<br />
/><br />
Blue would like to play elsewhere on the board. However, this would leave Red with a 2nd row [[ladder escape]] along the bottom edge. While this ladder escape may not look immediately threatening to Blue, it would be untidy to just leave it unattended. Instead, Blue tidies up by first playing 2, which forces Red to reconnect, say at 3. <br />
<hexboard size="4x5"<br />
coords="none"<br />
edges="bottom right"<br />
contents="B c2 R d1 1:d2 B 2:c3 R 3:d3"<br />
/><br />
Now Blue has taken away Red's ladder escape and is free to move elsewhere. In fact, Blue also gained a small amount of [[territory]].<br />
<br />
To illustrate that this can make a difference, consider the following position, with Blue to move. In this situation, "a" is winning, but "b" and all other moves are losing.<br />
<hexboard size="6x6"<br />
coords="none"<br />
edges="all"<br />
contents="R b3 e3 e4 B d3 d4 E a:d5 b:e2"<br />
/><br />
<br />
<br />
=== Obtuse corner example ===<br />
<br />
Red has just played 1, threatening to connect to the bottom edge. Blue responds at 2. This will result in a 2nd row [[ladder]] along the bottom edge.<br />
<hexboard size="5x5"<br />
coords="none"<br />
edges="bottom left"<br />
contents="R d2 e2 B d3 e3 R 1:c3 B 2:b5"<br />
/><br />
Let's assume that Red has a [[ladder escape]], so that Red will "win" the ladder. Red could start the ladder right away, but it is better to first tidy up the corner by playing 3 and 4:<br />
<hexboard size="5x5"<br />
coords="none"<br />
edges="bottom left"<br />
contents="R d2 e2 B d3 e3 R 1:c3 B 2:b5 R 3:b3 B 4:a5"<br />
/><br />
This gains a bit of territory for Red. Note that 3 is immediately forcing: if Blue does not respond, Red connects to the edge. On the other hand, if Red has already played and connected the ladder, 3 is no longer forcing.<br />
<br />
To illustrate that this can make a difference, consider the following position, with Red to move. In this situation, "a" is winning, but "b" and all other moves are losing.<br />
<hexboard size="5x5"<br />
coords="none"<br />
edges="all"<br />
contents="B b1 d3 b5 R c3 d5 E a:b3 b:c4"<br />
/><br />
<br />
=== Incomplete joseki ===<br />
<br />
Failing to correctly complete a [[joseki]] often results in an untidy situation.<br />
<br />
== Related concepts ==<br />
<br />
In Go, there is the concept of [https://senseis.xmp.net/?Aji aji], which means something like "the possibilities left in a position".<br />
<br />
[[category: Advanced Strategy]]<br />
[[category: Definition]]</div>Selingerhttps://www.hexwiki.net/index.php/Ladder_generation_templateLadder generation template2020-12-17T17:45:01Z<p>Selinger: /* Ladder creation templates on the 5th row */ Added a template.</p>
<hr />
<div>A '''ladder creation template''' is a kind of edge template that guarantees that the owner of the template can either connect to the edge or, failing that, get a specified ladder or ladders.<br />
<br />
There is not yet a [[naming of templates|naming convention]] for ladder creation templates, so all examples on this page are currently unnamed. Like edge templates, we classify ladder creation templates by the row on which the connecting stone is located, rather than by the kind of ladder it generates. In fact, some templates generate more than one ladder, for example a 4th row ladder going left or a 3rd row ladder going right. In an attempt to avoid confusion, we say "ladder creation template on the 3rd row", rather than "3rd row ladder creation template", to indicate that the template is a 3rd row template (but may, for example, generate a 2nd row ladder).<br />
<br />
On [http://www.drking.org.uk/hexagons/hex/templates.html David King's Hex template page], ladder creation templates are called "cascading templates". However, they should not be confused with what [http://www.mseymour.ca/hex_book/hexstrat.html Matthew Seymour's book] calls "cascading ladders", which is a different concept.<br />
<br />
== Examples ==<br />
<br />
We use horizontal arrows "→" and sometimes "←" to indicate where the ladder(s) will start. If the right and left ladders use the same color, it means that Red can get both ladders. If they use different colors, it means that Red has a choice between starting a ladder on the right or on the left, but cannot do both. The cells marked "→" and "←" must be empty for the templates to be valid.<br />
<br />
As usual, Red stones marked "↑" are assumed to be connected upwards, i.e., these are the stones that Red wants to connect to the bottom edge or ladder. Any cells that are shaded in grey are not part of the template and can be occupied by Blue.<br />
<br />
Many of the below templates are taken from [http://www.drking.org.uk/hexagons/hex/templates.html David King's Hex template page].<br />
<br />
When checking the templates, keep in mind that the templates do not in general guarantee that Red will get the indicated ladder. They only guarantee that Red will get at least the indicated ladder (or a better one) if Red doesn't connect to the edge outright.<br />
<br />
=== Ladder creation templates on the 2nd row ===<br />
<br />
<hexboard size="2x2"<br />
coords="none"<br />
edges="bottom"<br />
contents="R a1 S red:(b1 b2) E →:(b1 b2)"<br />
/><br />
<br />
<hexboard size="2x3"<br />
coords="none"<br />
edges="bottom"<br />
visible="-a1"<br />
contents="R b1 S grey:b2 S red:(c1 c2) E →:(c1 c2)"<br />
/><br />
<br />
=== Ladder creation templates on the 3rd row ===<br />
<br />
<hexboard size="3x3"<br />
coords="none"<br />
edges="bottom"<br />
visible="-a1 a2"<br />
contents="R b1 S red:(c1 c2 c3) E →:(c1 c2 c3)"<br />
/><br />
<br />
<hexboard size="3x3"<br />
coords="none"<br />
edges="bottom"<br />
visible="-a1 a2 b1"<br />
contents="R c1 S red:(c2 c3) red:(b2 a3) E →:(c2 c3) ←:(b2 a3)"<br />
/><br />
<br />
<hexboard size="3x4"<br />
coords="none"<br />
edges="bottom"<br />
visible="-a1 a2 b1"<br />
contents="R c1 S grey:c3 S red:(d2 d3) E →:(d2 d3)"<br />
/><br />
<br />
=== Ladder creation templates on the 4th row ===<br />
<br />
<hexboard size="4x4"<br />
coords="none"<br />
edges="bottom"<br />
visible="-area(a1,a3,b2,b1)"<br />
contents="R c1 S red:(d1 d2 d3 d4) E →:(d1 d2 d3 d4)"<br />
/><br />
<br />
<hexboard size="4x4"<br />
coords="none"<br />
edges="bottom"<br />
visible="-area(a1,a3,c1)"<br />
contents="R d1 S red:(d2 d3 d4) red:(c2 b3 a4) E →:(d2 d3 d4) ←:(c2 b3 a4)"<br />
/><br />
<br />
<hexboard size="4x5"<br />
coords="none"<br />
edges="bottom"<br />
visible="-area(a1,a3,c1)"<br />
contents="R d1 S red:(e3 e4) E →:(e3 e4)"<br />
/><br />
<br />
<hexboard size="4x6"<br />
coords="none"<br />
edges="bottom"<br />
visible="-area(a1,a3,c1) d1"<br />
contents="R f1 S red:(f3 f4) red:(b3 a4) E →:(f3 f4) ←:(b3 a4)"<br />
/><br />
<br />
=== Ladder creation templates on the 5th row ===<br />
<br />
<hexboard size="5x6"<br />
coords="none"<br />
edges="bottom"<br />
visible="-area(a1,a4,d1) d2"<br />
contents="R e1 S red:(f1--f5) E →:(f1--f5)"<br />
/><br />
<br />
<hexboard size="5x6"<br />
coords="none"<br />
edges="bottom"<br />
visible="-area(a1,a4,d1)"<br />
contents="R e1 S red:(f3--f5) E →:(f3--f5)"<br />
/><br />
<br />
<hexboard size="5x8"<br />
coords="none"<br />
edges="bottom"<br />
visible="-area(a1,a4,d1) d2 e1 f1"<br />
contents="R h1 S red:(h3--h5) red:(c3--a5) E →:(h3--h5) E ←:(c3--a5)"<br />
/><br />
<br />
<hexboard size="5x5"<br />
coords="none"<br />
edges="bottom"<br />
visible="-area(a1,a4,d1)"<br />
contents="R ↑:e1 e3 S red:(e4--e5) red:(c3--a5) E →:(e4--e5) ←:(c3--a5)"<br />
/><br />
<br />
<hexboard size="5x6"<br />
coords="none"<br />
edges="bottom"<br />
visible="-area(a1,a4,d1)"<br />
contents="R e1 f1 S red:(f4--f5) red:(c3--a5) E →:(f4--f5) ←:(c3--a5)"<br />
/><br />
Red can choose between getting a 2nd row ladder to the right and a 3rd row ladder to the left, or vice versa.<br />
<br />
<hexboard size="5x5"<br />
coords="none"<br />
edges="bottom"<br />
visible="area(c1,b2,a5,d5,e2,e1)-d1"<br />
contents="R arrow(12):(c1,e1) S red:(d4--d5) E arrow(3):(d4--d5)"<br />
/><br />
<br />
=== Ladder creation templates on the 6th row ===<br />
<br />
<hexboard size="6x7"<br />
coords="none"<br />
edges="bottom"<br />
visible="-area(a1,a5,e1)"<br />
contents="R f1 e2 S red:(g5--g6) blue:(b5--a6) E →:(g5--g6) ←:(b5--a6) +:d4"<br />
/><br />
Red must choose between the ladder going left and the ladder going right (Red cannot force both simultaneously). The cell marked "+" is the only place where Blue can move to prevent Red from connecting to the edge outright.<br />
<br />
<hexboard size="6x7"<br />
coords="none"<br />
edges="bottom"<br />
visible="-area(a1,a5,e1)"<br />
contents="R f1 g1 S red:(g4--g6) blue:(c4--a6) E →:(g4--g6) ←:(c4--a6)"<br />
/><br />
Red must choose between the ladder going left and the ladder going right (Red cannot force both simultaneously).<br />
<br />
<hexboard size="6x6"<br />
coords="none"<br />
edges="bottom"<br />
visible="-area(a1,a5,e1)"<br />
contents="R ↑:f1 f3 S red:(f4--f6) blue:(d3--a6) E →:(f4--f6) ←:(d3--a6)"<br />
/><br />
Red must choose between the ladder going left and the ladder going right (Red cannot force both simultaneously).<br />
<br />
<hexboard size="6x9"<br />
coords="none"<br />
edges="bottom"<br />
visible="area(b6,h6,h3,g3,g1)"<br />
contents="R ↑:g1 g3 S red:(h5--h6) E →:(h5--h6)"<br />
/><br />
<br />
<hexboard size="6x9"<br />
coords="none"<br />
edges="bottom"<br />
visible="area(a6,i6,i4,g2,g1,e3,d3)"<br />
contents="R ↑:g1 g3 S red:(i5--i6) red:(b5--a6) E →:(i5--i6) ←:(b5--a6) +:(g2 e4 g4)"<br />
/><br />
Red can get both ladders simultaneously. The cells marked "+" are the only ones where Blue can move to prevent Red from connecting to the edge outright.<br />
<br />
[[category:edge templates]]<br />
[[category:definition]]</div>Selingerhttps://www.hexwiki.net/index.php/BoardBoard2020-12-12T19:14:55Z<p>Selinger: Edited categories</p>
<hr />
<div>== Board dimensions ==<br />
<br />
The Hex '''board''' is composed of hexagons, called '''hexes''' or '''cells''', arranged in an n×n rhombus, where n is an integer greater than zero. Thus, Hex can be played on boards of different sizes. Currently, 11×11, 13×13, and 19×19 are the most common board sizes. <br />
<br />
<hexboard size="7x7"<br />
coords="all"<br />
edges="all"<br />
/><br />
<br />
Less commonly, Hex can also be played on [[parallelogram boards|non-rhombic board]]s of size n&times;m. However, in that case, one of the players has an [[Theory#Winning_strategy_for_non-square_boards|easy winning strategy]], so non-rhombic boards typically only appear in [[Puzzles|Hex puzzles]] or in certain kinds of [[handicap]] games.<br />
<br />
== Corners ==<br />
<br />
The board has four corners. Two of them are '''acute corners''' and two of them are '''obtuse corners'''. In the above illustration, a1 and g7 are the acute corners, and a7 and g1 are the obtuse corners.<br />
<br />
== Edges ==<br />
<br />
The four '''edges''' of the board are colored with two colors, in such a way that parallel edges have the same color. In this Wiki, the color used by the first player is red, and the color used by the second player is blue. The edge coloring follows the order red-blue-red-blue, when traversing the edges counterclockwise starting from an acute corner. This means that if an acute corner is at 10 o'clock, the top and bottom edges are red and the left and right edges are blue.<br />
<br />
Another common coloring scheme is black (for the first player) and white (for the second player). In any case, the orientation of the board stays the same, with the first player's edges in place of red, and the second player's edges in place of blue.<br />
<br />
== Ranks, files, and coordinates ==<br />
<br />
A '''rank''' or '''row''' of the board is a line of hexes parallel to a red (or first player) edge. Ranks are numbered 1,2,3,...<br />
A '''file''' or '''column''' is a line of hexes parallel to a blue (or second player) edge. Files are lettered a,b,c,...<br />
Each hex is identified by its '''coordinates''', which are given by file and rank, for example, a1, b5, d3. The coordinates are always arranged so that a1 is an acute corner.<br />
<br />
In the following diagram, the blue cells are on the c-file, the red cells are on the 4-rank, and the grey cell is c4.<br />
<br />
<hexboard size="7x7"<br />
coords="all"<br />
edges="all"<br />
contents="S blue:c1--c7 red:a4--g4 gray:c4"<br />
/><br />
<br />
== Diagonals ==<br />
<br />
Each board of size n&times;n has a '''short diagonal''' and a '''long diagonal'''. In the following diagram, the short diagonal is red, the long diagonal is blue, and the '''center''' of the board is on both diagonals (grey).<br />
<hexboard size="7x7"<br />
coords="all"<br />
edges="all"<br />
contents="S red:g1--a7 blue:a1--g7 gray:d4"<br />
/><br />
<br />
== Areas of the board ==<br />
<br />
The board can be roughly divided into 9 areas: two acute corner areas (A), two obtuse corner areas (B), two areas near red edges (C), two areas near blue edges (D), and the center (E). <br />
<hexboard size="7x7"<br />
coords="all"<br />
edges="all"<br />
contents="E A:(b2 f6) B:(b6 f2) C:(d2 d6) D:(b4 f4) E:(d4)"<br />
/><br />
On the 7&times;7 board above, these areas are very small and close to each other. But on larger boards, these areas become more pronounced and important. For example, there is an entire theory devoted to [[Joseki|corner play]] in Hex.<br />
<br />
== Referring to parts of the board ==<br />
<br />
When discussing and commenting games, it is common to refer to the various areas of the board as the "upper left" corner, the "bottom" edge, etc. For boards that are oriented with the a1 corner at 9 o'clock, some people also use terms such as the "south-west" edge. <br />
<br />
However, one should keep in mind that not all players orient their boards the same way. Some internet game sites have the a1 corner at 8 o'clock, 9 o'clock, or 10 o'clock. Some software permits players to rotate the board to their individual preferences (and not surprisingly, different players actually do have different preferences!). Physical game boards can certainly be rotated and are usually looked at from different directions by the two players. Therefore, when commenting games, it is preferable to refer to parts of the board as the "a1-corner", the "11-edge", the "a11-corner area", and so on.<br />
<br />
On this Wiki, the boards are (almost) always oriented with the a1 corner at 10 o'clock, and when terms such as "top", "bottom", "left", and "right" are used on this Wiki, they always refer to this orientation.<br />
<br />
[[Category:Definition]]<br />
[[Category:Rules and Conventions]]</div>Selingerhttps://www.hexwiki.net/index.php/CrescentCrescent2020-12-11T18:32:51Z<p>Selinger: Added category</p>
<hr />
<div>The '''crescent''' is an [[interior template]] with 4 stones.<br />
<br />
<hexboard size="3x3"<br />
coords="hide"<br />
edges="none"<br />
visible="-c3"<br />
contents="R a1 a3 b3 c2"<br />
/><br />
<br />
[[category:interior templates]]</div>Selinger