Crafty V9.22
Robert Hyatt
I've just copied the source files for Crafty V9.22 to the ftp machine
willis.cis.uab.edu, directory=pub/hyatt. I'm currently copying a
crafty.linux executable, and, shortly, a crafty.sun executable. I'll
post the others as they are compiled by volunteers and sent back to
me.
One thing I do need is a quick test if anyone has the autoplay stuff
up and going and can compile Crafty as well. I've tried to merge the
autoplay code in, but I have no way to test it. There's a few curious
points that are going to cause problems (apparently no underpromotion
is possible for example) regardless of what Crafty does, but the basic
"gist" is there. All I need is "input" for what doesn't work correctly.
Be *sure* to play more than one game, to make sure that the second (and
additional) games get started correctly, that Crafty continues to ponder
like it should, etc. Probably a few details to work out.
Major difference is quite a bit of changes to the evaluation. Seems to
be better on ICC, but, as I've mentioned before, this is a very subjective
assessment.
As always, feedback is welcome.
As far as the book, two major threads have come up: (1) make it readable
by a beginner and (2) make it useful to someone that is not a beginner.
My intent was, from the beginning, to do both. For example, the chapter
on hash tables might look something like this:
1. The basic idea
2. what data is useful in a hash table and how is it used to reduce the
stuff searched?
3. an actual implementation of a hash table entry, taken from Crafty,
with each field defined, explained, and justified.
4. a more technical discussion about replacement policies and how they
affect things.
5. a section on "bizarre behavior" that hash tables often produces, that
could lead to lots of debugging when nothing is really broken.
So, beginners start at section 1, non-beginners start at section 2 if you
have not done one yourself, the rest start at sections 3,4 or 5, depending
on your experience level. My intent would be to make each section have a
very technical section that most anyone would find revealing, exactly the
sort of thing I wish I had had 25 years ago. I remember nearly memorizing
the Chess 4.x chapter in "Chess Skill in Man and Machine", but also remember
how disappointed I was when it came time to look at hashing and discovering
that almost all the "meat" was "left to the reader to discover".
Also, I don't plan on making this a "Crafty" book at all, although certain
parts of the book will detail specific "crafty'isms" like the rotated bitmap
attack generation, and bit-parallel evaluation ideas. I also plan on
discussing offset board representations and move generation as well, and
cover such relatively old topics as board representations for various options
like the oft-mentioned X88 move generator, etc.
Parts would be bitmap-specific, parts would be offset-specific, and most
would be independent of the specific board representation you might want
to use when you "roll your own."
Still studying the idea, so, as always suggestions are welcome.
Bob
--
Robert Hyatt Computer and Information Sciences
hy...@cis.uab.edu University of Alabama at Birmingham
(205) 934-2213 115A Campbell Hall, UAB Station
(205) 934-5473 FAX Birmingham, AL 35294-1170