RE[2]: WinBoard for watching Chess960 games

[email protected] Wed, 02 Mar 2022 09:37:25 +0000
Newsgroups gmane.comp.gnu.xboard.devel
Message-ID <[email protected]>
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OK, I see what the problem is: the game record provides the FEN tag befor=
e the Variant tag.=0ASo when the game is loaded while WinBoard is not yet=
 in FRC mode, the Variant tag will=0Atrigger a variant switch to FRC, whi=
ch will also trigger a new shuffling of the start position.=0AThis has on=
ly a 1-in-96 chance of reproducing the position from the FEN tag, and in =
all=0Aother cases the following moves will no longer fit the start positi=
on.=0AIf I change the order of these tags, the game loads without problem=
s.=0AIf WinBoard is set to FRC first, through the New Variant dialog, the=
 game also loads=0Awithout problems, irrespective of the tag order. This =
should be considered a work-around=0Afor the mentioned problem.=0AI guess=
 loading a game of a variant that is not currently selected is bound to c=
ause trouble=0Aif the Variant tag does not come before other variant-spec=
ific tags, such as the FEN tag.=0ABecause the FEN would be parsed in the =
wrong context: piece IDs in the FEN can have different=0Ameaning in diffe=
rent variants, and even the board size could be different, or extra field=
s=0Acould be present (e.g. for recording the number of remaining checks i=
n 3-checks) which=0Awould get ignored.=0ANow the Variant tag is an extens=
ion to the PGN standard, and there is thus no official standard=0Athat ex=
plicitly declares the ordering of the tags as used by TCEC as illegal. Al=
though a lot=0Aof misery could be avoided by declaring it is. Nevertheles=
s, for the convenience of being=0Aable to automatically load such 'illogi=
cally encoded' games (e.g. when using the file=0Aassociation for loading =
the game by double-clicking the PGN file icon), it would be better=0Ato d=
efer processing of a FEN tag until move number 1 is encountered.=0AOp di.=
, mrt. 1, 2022 om 20:47, Tim Mann  schreef:=0AI'm not really working on x=
board or WinBoard anymore. I'm cc'ing the developers mailing list on this=
 reply in case anyone else can help.=0AOn Tue, Mar 1, 2022 at 10:46 AM Va=
dim Trofimov  wrote:=0AHello, Tim Mann,=0AI really like your WinBoard pro=
gram. I use Winboard 4.2.7 and Winboard 4.8.0 to watch games by downloadi=
ng and opening the archive in pgn format. On the website https://tcec-che=
ss.com/#x=3Darchive (https://tcec-chess.com/#x=3Darchive) there is an arc=
hive of computer engine games, for example, Season 21, where FRC 4 is Fis=
cher Chess 960: Winboard 4.2.7 Winboard 4.8.0 does not show Fischer chess=
 960 games, they write an error message "Illegal move" on moves 0-0; 0-0-=
0 and other moves if there are comments in parentheses in the pgn text. I=
n previous seasons, computer engines also played Fischer's 960 chess, and=
 Winboard also writes an error message "Illegal move" on moves 0-0; 0-0-0=
. Please fix these Winboard errors to be able to view Fischer's 960 chess=
 games. =0A=0APS: Archive of people's games in png format from the site c=
hess-poster.com (http://chess-poster.com) WinBoard shows without errors.=
=0ABest wishes,=0AVadim Trofimov from Russia

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<!DOCTYPE html><html><head><meta http-equiv=3D"Content-Type" content=3D"t=
ext/html; charset=3Dutf-8" /></head><body><div data-crea=3D"font-wrapper"=
 style=3D"font-family: Tahoma, sans-serif; font-size: 16px; direction: lt=
r"><div style=3D"font-family: Tahoma; font-size: 16px"></div><br><div>OK,=
 I see what the problem is: the game record provides the FEN tag before t=
he Variant tag.</div><div>So when the game is loaded while WinBoard is no=
t yet in FRC mode, the Variant tag will</div><div>trigger a variant switc=
h to FRC, which will also trigger a new shuffling of the start position.<=
/div><div>This has only a 1-in-96 chance of reproducing the position from=
 the FEN tag, and in all</div><div>other cases the following moves will n=
o longer fit the start position.<br></div><div><br></div><div>If I change=
 the order of these tags, the game loads without problems.</div><div><br>=
</div><div>If WinBoard is set to FRC first, through the New Variant dialo=
g, the game also loads</div><div>without problems, irrespective of the ta=
g order. This should be considered a work-around</div><div>for the mentio=
ned problem.<br></div><div><br></div><div>I guess loading a game of a var=
iant that is not currently selected is bound to cause trouble</div><div>i=
f the Variant tag does not come before other variant-specific tags, such =
as the FEN tag.</div><div>Because the FEN would be parsed in the wrong co=
ntext: piece IDs in the FEN can have different</div><div>meaning in diffe=
rent variants, and even the board size could be different, or extra field=
s</div><div>could be present (e.g. for recording the number of remaining =
checks in 3-checks) which</div><div>would get ignored.</div><div><br></di=
v><div>Now the Variant tag is an extension to the PGN standard, and there=
 is thus no official standard</div><div>that explicitly declares the orde=
ring of the tags as used by TCEC as illegal. Although a lot</div><div>of =
misery could be avoided by declaring it is. Nevertheless, for the conveni=
ence of being</div><div>able to automatically load such 'illogically enco=
ded' games (e.g. when using the file</div><div>association for loading th=
e game by double-clicking the PGN file icon), it would be better</div><di=
v>to defer processing of a FEN tag until move number 1 is encountered.<br=
></div><div></div><br><br><div data-anchor=3D"reply-title">Op di., mrt. 1=
, 2022 om 20:47, Tim Mann &lt;[email protected]&gt; schreef:</div><blockqu=
ote><div><div><div dir=3D"ltr"><div>I'm not really working on xboard or W=
inBoard anymore. I'm cc'ing the developers mailing list on this reply in =
case anyone else can help.</div><div><br></div></div><br><div><div dir=3D=
"ltr">On Tue, Mar 1, 2022 at 10:46 AM Vadim Trofimov &lt;<a href=3D"mailt=
o:[email protected]" target=3D"_blank" tabindex=3D"-1" rel=3D"external=
" class=3D"external" style=3D"cursor: inherit;">[email protected]</a>&=
gt; wrote:<br></div><blockquote style=3D"margin: 0px 0px 0px 0.8ex;border=
-left: 1px solid rgb(204,204,204);padding-left: 1ex"><div><div style=3D"f=
ont-family: Helvetica Neue,Helvetica,Arial,sans-serif;font-size: 16px"><d=
iv dir=3D"ltr"><div dir=3D"ltr"> <div><div>Hello, Tim Mann,</div><div>I r=
eally like your WinBoard program. I use Winboard 4.2.7 and Winboard 4.8.0=
 to watch games by downloading and opening the archive in pgn format. On =
the website <a href=3D"https://tcec-chess.com/#x=3Darchive" target=3D"_bl=
ank" tabindex=3D"-1" rel=3D"external" class=3D"external" style=3D"cursor:=
 inherit;">https://tcec-chess.com/#x=3Darchive</a> there is an archive of=
 computer engine games, for example, Season 21, where FRC 4 is Fischer Ch=
ess 960: Winboard 4.2.7 Winboard 4.8.0 does not show Fischer chess 960 ga=
mes, they write an error message "Illegal move" on moves 0-0; 0-0-0 and o=
ther moves if there are comments in parentheses in the pgn text. In previ=
ous seasons, computer engines also played Fischer's 960 chess, and Winboa=
rd also writes an error message "Illegal move" on moves 0-0; 0-0-0. Pleas=
e fix these Winboard errors to be able to view Fischer's 960 chess games.=
=C2=A0</div><div><br></div><div dir=3D"ltr">PS: Archive of people's games=
 in png format from the site <a href=3D"http://chess-poster.com" target=
=3D"_blank" tabindex=3D"-1" rel=3D"external" class=3D"external" style=3D"=
cursor: inherit;">chess-poster.com</a> WinBoard shows without errors.</di=
v></div><br></div><div><br></div><div>Best wishes,<br></div></div><div di=
r=3D"ltr">Vadim Trofimov=C2=A0</div><div dir=3D"ltr">from Russia</div><di=
v><br></div><div><div style=3D"font-family: Helvetica,Arial,sans-serif;fo=
nt-size: 16px"><br><br></div></div></div></div></blockquote></div></div><=
/div></blockquote></div></body></html>

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