Re: [gnugo-devel] arend_3_7.2: Don't trust owl defense more than tactical analysis

[Gunnar Farneback]

Arend wrote:
> This patch changes the policy for OWL_DEFEND_MOVE(...) move reasons. Now
> only those parts of the affected dragon are marked saved which are either
> tactically stable or tactically defended by this move.

Sounds like a good workaround for the owl weakness of not
understanding the concept of losing tails. Of course not all such
tails are lost tactically, but this should help reduce the effects. It
may also help with certain cases of incorrect amalgamation of
tactically unstable strings.

There may be some issues with owl and tactical results involving ko.

> Finally, I feel it would help to have a list of worms belonging to each
> dragon. This could be done by circularly linking the worm origins, starting
> at the dragon origin.

Also a good idea. I think we want to hide the data structure though,
having an interface similar to

for (w = first_dragon_worm(pos); w != NO_MOVE; w = next_dragon_worm(w)) {
    ...
}

/Gunnar