Geschrieben von: / Posted by: Tord Romstad at 10 March 2004 11:29:34:
Als Antwort auf: / In reply to: Future of BigLion geschrieben von: / posted by: Matthias Gemuh at 09 March 2004 21:37:05:
"Don't take things too seriously - if you get tired, stop programming until you're motivated again (even if it takes years!)"
I feel like obeying immediately !!
This is indeed wisdom, but unfortunately it is virtually impossible to follow,
once you have made your engine public. All these pesky users keep sending us
nice games, bug reports, requests for new features, as well as asking when the
next version will be available. I often wish I could let my engine die and
never again touch my ugly and rotten old source code, but it's too late by
now.
And you think we'll let you do that? Dream on.

Tord
Hi Tord,
thanks for the Gothmog with fritz-hash option.
That means I can now use my favorite UCI engine under my favorite GUI.
As for programming, I am too lazy to start from scratch again and too stupid to fix the mighty bugs in my search.
Frequently, when I search twice under identical conditions, I get 2 different "best" moves and miss the best move.
Against all opponents below Elo 2250, the performance of BigLion can be quickly determined by simply tossing a coin.
I don't program much now. When my search shall be stable, I shall limit my
chess programming to "Evaluation and Fun Features". No search improvements.
Thanks for the kind words, Matthias! I wish I had the pleasure of playing
with your engines more often, too. As you know, I live in a Mac OS/Linux
world and don't have many engines to play against.
I have tried to start from scratch a couple of times myself lately, but
the magnitude of the task is scary. I had forgotten how much work it
takes to produce an engine which plays half decent chess. In a way, I
find it to be even more difficult the second time. When Gothmog played
its first ugly moves, I was happy to see it play chess at all, and I
enjoyed watching the games, even though it lost virtually all of them.
But now, when I already have a moderately strong engine, creating a new
and (initially) awfully weak engine and watching it improve slowly will
be unbearably painful. Nevertheless, sooner or later the difficulties
of maintaining my current, badly written code and struggling with old,
fundamentally brain-damaged design decisions will force me to make a
fresh start.
Concerning the mighty bugs in your search, the best way to fix them is
probably to make your search as simple as possible. Throw away all tricks,
and just use plain alpha-beta. It will be very slow, of course, but
the bugs should be easier to locate and fix. When everything appears to
work, proceed to add all the stuff you removed, but do it very slowly.
Add one thing at a time, and test it very thorougly and try to make sure
there are no bugs before you attempt to add further tricks.
This is very common to me, too. And if I make just a minor, apparently
harmless change to my move ordering, this often results in wildly different
best moves and scores from the same position.
Again, I often feel the same.

That's where I plan to concentrate my attention in the near future, too.
The last half year, I have been working almost exclusively on my search.
It's definitely time for "Evaluation and Fun Features".
Do you have any ideas for fun features, by the way? Is there anything
you would like to see in future versions of Gothmog?
Of course, Matthias is not the only person who is allowed to answer these
questions.

Tord