Re: [gnugo-devel] Heeroy game?

[Gunnar Farneback]

Trevor wrote:
> http://www.lysator.liu.se/~gunnar/gnugo/nngs/games/gnugo-3.1.22-heeroy-200201252006.sgf
> 
> As best I can tell, GNU Go violated the super ko rule, and NNGS
> forced a resignation.  I'm not at all sure, though.

Not exactly. NNGS detected a superko violation and told GNU Go that
the move was illegal. Then gnugoclient voluntarily resigned the game
for GNU Go. This is, by the way, the only circumstance under which GNU
Go will currently resign an NNGS game.

This game is a good case for generating aftermath moves if the
opponent insists on continuing to play even though we have passed,
like Trevor has suggested. When the aftermath code stops generating
moves, *nothing* bad can ever happen to our living stones (*),
regardless of rule subtleties, and dead opponent stones will stay
dead.

My suggestion for how to handle this, assuming we have found no move
up until fill_liberty(), is (in fairly abstract terms):

1. If the opponent's last move was a pass, pass.
2. If we are behind and territory scoring is used, pass.
3. If we haven't passed during the last N moves, pass.
4. Generate a move to reinforce the stones adjacent to the dragon of
   the last opponent move.
5. Generate a move to reduce the potential eyespace (in a very broad
   sense) for the dragon of the last opponent move.
6. Generate an aftermath move.

(*) Stones in seki are an exception, in that the opponent has the
option to threaten to capture them at the cost of losing his own
stones when we answer.

> Please add it the gnugo/regression/games/nngs directory.

Done.

Dan wrote:
> The index to the games archived at lysator seems to
> be incomplete. There are older games than this one
> linked at:
> 
> http://www.lysator.liu.se/~gunnar/gnugo/nngs/

This is intentional and intended to make it easier to find interesting
games. Adjourned games are removed after three days, ordinary games
after a week, "interesting" (bold face) games are stored a month and
crashes until manually removed. The index is updated when a new game
arrives. 

> However you can get a fuller index at least from Netscape
> by going to the directory
> 
> http://www.lysator.liu.se/~gunnar/gnugo/nngs/games/

Game records remain in the directory for a month regardless of status.
This directory listing is provided by the web server and independent
of browser.

/Gunnar