[xogo.git] / variants / Checkered / complete_rules.html

<!doctype html>
<html>
<head>
  <title>Checkered Rules</title>
  <link href="/common.css" rel="stylesheet"/>
  <link href="/variants/Checkered/style.css" rel="stylesheet"/>
</head>
<body>
<div class="full-rules">
<h1>Checkered Rules</h1>

<div>
<p class="boxed">
  The capture of an enemy piece produces a new "checkered" piece belonging
  to both players.
</p>
<figure class="show-pieces">
  <img src="/pieces/Checkered/cp.svg"/>
  <img src="/pieces/Checkered/cr.svg"/>
  <img src="/pieces/Checkered/cn.svg"/>
  <img src="/pieces/Checkered/cb.svg"/>
  <img src="/pieces/Checkered/cq.svg"/>
  <figcaption>Checkered pieces, born after captures.</figcaption>
</figure>
<p>Note: the initial French name for this variant is "l'Échiqueté".</p>
<p>The game potentially evolves in two stages.</p>
</div>

<div>
<h2 class="stageDelimiter">Stage 1</h2>
<h3>Basics</h3>
<ol>
  <li>
    Each capture produces a new piece, taking on nature of
    the capturing or captured one.
  </li>
  <li>
    The new piece arising from a capture has a new color:
    "checkered", as illustrated above.
  </li>
  <li>
    All checkered pieces belong to the player in turn and can
    capture the opponents pieces.
  </li>
</ol>
<p>Remarks:</p>
<ul>
  <li>
    A non-capturing checkered move cannot be "undone" right after since
    this would repeat the same position.
  </li>
  <li>Checkered pieces cannot be captured.</li>
</ul>
<figure>
  <div class="diag"
       data-fen='2kr4/pp6/2p5/4ss1r/1P2ns1P/2Np4/P1P1P1BP/R2o1RK1'>
  </div>
  <figcaption>
    Black plays Rxh4=P. (Checkered pawn to) h5 is allowed then,
    because piece's nature changed.
    
  </figcaption>
</figure>
<h3>Pawns</h3>
<ul>
  <li>
    Pawns can jump two squares only from their initial rank, and only once in
    the game. A checkered pawn keeps this right if the starting pawn
    did not use it.
  </li>
  <li>
    Checkered pawns cannot capture en passant, because while the pawn was
    "passing" they were of the same color.
    
  </li>
</ul>
<h3>Stalemate or checkmate?</h3>
<p>
  The following diagram seems to show a mating pattern, but the king if
  "attacked" by a checkered pawn &ndash; which still belongs to white.
  Therefore, it can be considered that it's not really a check because
  white is unable to "give back the turn".
  Without the black bishop on a7 it would be mate (without debate), because
  the king could virtually go to g1 before being captured by the
  chameleon pawn.
  
</p>
<figure>
  <div class="diag"
       data-fen='7k/b5pp/8/8/8/8/6ss/7K w 4 {"flags":"88880000000000000011"}'>
  </div>
  <figcaption>After 1...g2+(#?).</figcaption>
</figure>
<p>
  The interface considers that it's mate in both cases, following the idea
  "it's checkmate if we cannot move, and the opponent on its turn could
  take the king" (maybe after an impossible move).
  
</p>
</div>

<div>
<h2 class="stageDelimiter">Stage 2</h2>
<p class="italic">
  This stage can be disabled by unselecting "With switch" at game creation.
</p>
<p>
  During the game one of the two players can decide to take control of the
  checkered pieces.
  They thus become autonomous and vulnerable to being captured - stage 2
  begins. The other player is in charge of both the white and black pieces, and
  tries to eliminate checkered pieces.
  The checkered side wins by checkmating either the white or black king.
</p>
<p>
  To take the checkered pieces, play a move that "takes opponent's king" with
  your king, and then execute a move. This is possible only if no such move
  can capture a king.
</p>
<h4>Variant of stage 2 (unimplemented)</h4>
<p>
  An observer could decide to join the game by taking the checkered pieces
  at any moment.
  It then becomes a chess game with three players, with some subtelties to be
  resolved. It was tested in some (real life) games.
</p>
<h3>Special moves</h3>
<p>Checkered pawns can...</p>
<ul>
  <li>move and capture in either direction;</li>
  <li>take en passant,</li>
  <li>be promoted on either the first or eighth row.</li>
</ul>
</div>

<div>
<h3>Credits</h3>
<ul>
  <li>
    The rules of Checkered Chess were thought up by Patrick Bernier and
    developed with the help of Benjamin Auder around 2011-2012.
  </li>
  <li>
    Thanks also to Olive Martin, Christian Poisson, Bevis Martin, Laurent
    Nouhaud and Frédéric Fradet.
  </li>
</ul>
</div>

</body>
<script src="/utils/drawDiagrams.js"></script>
<script>fenToDiag("Checkered");</script>
</html>
Commit	Line	Data
	1	<!doctype html>
	2	<html>
	3	<head>
	4	<title>Checkered Rules</title>
	5	<link href="/common.css" rel="stylesheet"/>
	6	<link href="/variants/Checkered/style.css" rel="stylesheet"/>
	7	</head>
	8	<body>
	9	<div class="full-rules">
	10	<h1>Checkered Rules</h1>
	11
	12	<div>
	13	<p class="boxed">
	14	The capture of an enemy piece produces a new "checkered" piece belonging
	15	to both players.
	16	</p>
	17	<figure class="show-pieces">
	18	<img src="/pieces/Checkered/cp.svg"/>
	19	<img src="/pieces/Checkered/cr.svg"/>
	20	<img src="/pieces/Checkered/cn.svg"/>
	21	<img src="/pieces/Checkered/cb.svg"/>
	22	<img src="/pieces/Checkered/cq.svg"/>
	23	<figcaption>Checkered pieces, born after captures.</figcaption>
	24	</figure>
	25	<p>Note: the initial French name for this variant is "l'Échiqueté".</p>
	26	<p>The game potentially evolves in two stages.</p>
	27	</div>
	28
	29	<div>
	30	<h2 class="stageDelimiter">Stage 1</h2>
	31	<h3>Basics</h3>
	32	<ol>
	33	<li>
	34	Each capture produces a new piece, taking on nature of
	35	the capturing or captured one.
	36	</li>
	37	<li>
	38	The new piece arising from a capture has a new color:
	39	"checkered", as illustrated above.
	40	</li>
	41	<li>
	42	All checkered pieces belong to the player in turn and can
	43	capture the opponents pieces.
	44	</li>
	45	</ol>
	46	<p>Remarks:</p>
	47	<ul>
	48	<li>
	49	A non-capturing checkered move cannot be "undone" right after since
	50	this would repeat the same position.
	51	</li>
	52	<li>Checkered pieces cannot be captured.</li>
	53	</ul>
	54	<figure>
	55	<div class="diag"
	56	data-fen='2kr4/pp6/2p5/4ss1r/1P2ns1P/2Np4/P1P1P1BP/R2o1RK1'>
	57	</div>
	58	<figcaption>
	59	Black plays Rxh4=P. (Checkered pawn to) h5 is allowed then,
	60	because piece's nature changed.
	61
	62	</figcaption>
	63	</figure>
	64	<h3>Pawns</h3>
	65	<ul>
	66	<li>
	67	Pawns can jump two squares only from their initial rank, and only once in
	68	the game. A checkered pawn keeps this right if the starting pawn
	69	did not use it.
	70	</li>
	71	<li>
	72	Checkered pawns cannot capture en passant, because while the pawn was
	73	"passing" they were of the same color.
	74
	75	</li>
	76	</ul>
	77	<h3>Stalemate or checkmate?</h3>
	78	<p>
	79	The following diagram seems to show a mating pattern, but the king if
	80	"attacked" by a checkered pawn – which still belongs to white.
	81	Therefore, it can be considered that it's not really a check because
	82	white is unable to "give back the turn".
	83	Without the black bishop on a7 it would be mate (without debate), because
	84	the king could virtually go to g1 before being captured by the
	85	chameleon pawn.
	86
	87	</p>
	88	<figure>
	89	<div class="diag"
	90	data-fen='7k/b5pp/8/8/8/8/6ss/7K w 4 {"flags":"88880000000000000011"}'>
	91	</div>
	92	<figcaption>After 1...g2+(#?).</figcaption>
	93	</figure>
	94	<p>
	95	The interface considers that it's mate in both cases, following the idea
	96	"it's checkmate if we cannot move, and the opponent on its turn could
	97	take the king" (maybe after an impossible move).
	98
	99	</p>
	100	</div>
	101
	102	<div>
	103	<h2 class="stageDelimiter">Stage 2</h2>
	104	<p class="italic">
	105	This stage can be disabled by unselecting "With switch" at game creation.
	106	</p>
	107	<p>
	108	During the game one of the two players can decide to take control of the
	109	checkered pieces.
	110	They thus become autonomous and vulnerable to being captured - stage 2
	111	begins. The other player is in charge of both the white and black pieces, and
	112	tries to eliminate checkered pieces.
	113	The checkered side wins by checkmating either the white or black king.
	114	</p>
	115	<p>
	116	To take the checkered pieces, play a move that "takes opponent's king" with
	117	your king, and then execute a move. This is possible only if no such move
	118	can capture a king.
	119	</p>
	120	<h4>Variant of stage 2 (unimplemented)</h4>
	121	<p>
	122	An observer could decide to join the game by taking the checkered pieces
	123	at any moment.
	124	It then becomes a chess game with three players, with some subtelties to be
	125	resolved. It was tested in some (real life) games.
	126	</p>
	127	<h3>Special moves</h3>
	128	<p>Checkered pawns can...</p>
	129	<ul>
	130	<li>move and capture in either direction;</li>
	131	<li>take en passant,</li>
	132	<li>be promoted on either the first or eighth row.</li>
	133	</ul>
	134	</div>
	135
	136	<div>
	137	<h3>Credits</h3>
	138	<ul>
	139	<li>
	140	The rules of Checkered Chess were thought up by Patrick Bernier and
	141	developed with the help of Benjamin Auder around 2011-2012.
	142	</li>
	143	<li>
	144	Thanks also to Olive Martin, Christian Poisson, Bevis Martin, Laurent
	145	Nouhaud and Frédéric Fradet.
	146	</li>
	147	</ul>
	148	</div>
	149
	150	</body>
	151	<script src="/utils/drawDiagrams.js"></script>
	152	<script>fenToDiag("Checkered");</script>
	153	</html>