Search found 1739 matches

by Gerd Isenberg
Tue Apr 20, 2021 5:34 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: I did some magic bitboard "science" and mostly learned not to worry about it
Replies: 13
Views: 545

Re: I did some magic bitboard "science" and mostly learned not to worry about it

A variation of the classical approach using x^(x-1) separation and pure calculation for orthogonal lines and tiny lookup for diagonals.
Very nice!
by Gerd Isenberg
Sun Mar 28, 2021 7:51 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Computers, Chess and Long-Range Planning, by Michail M. Botvinnik
Replies: 7
Views: 1700

Re: Computers, Chess and Long-Range Planning, by Michail M. Botvinnik

In the null-move context, to determine attack/defense targets and trajectories see also Botvinnik-Markoff Extension. Botvinnik already proposed Vector Attacks aka 15x15 boards with superimposed lookup as used in Pioneer.
by Gerd Isenberg
Wed Mar 10, 2021 6:48 pm
Forum: Computer Chess Club: General Topics
Topic: Plea for a computerchess beginners forum or FAQ
Replies: 14
Views: 1562

Re: Plea for a computerchess beginners forum or FAQ

Rebel wrote:
Wed Mar 10, 2021 5:43 pm
Best computer chess website on the Internet Gerd.
Thanks for the compliments, Ed. But don't exaggerate :)
by Gerd Isenberg
Wed Mar 10, 2021 6:42 pm
Forum: Computer Chess Club: General Topics
Topic: Plea for a computerchess beginners forum or FAQ
Replies: 14
Views: 1562

Re: Plea for a computerchess beginners forum or FAQ

Can you please provide a link to the wrong pseudo code in CPW? And a link to the discussion here as well. I really hope, after more than 10 years of editing CPW, it is a little bit more than nostalgic stuff ;-) Don't get me wrong, the CPW is a great resource to get started with things, and to get t...
by Gerd Isenberg
Wed Mar 10, 2021 5:03 pm
Forum: Computer Chess Club: General Topics
Topic: Plea for a computerchess beginners forum or FAQ
Replies: 14
Views: 1562

Re: Plea for a computerchess beginners forum or FAQ

The chess programming Wiki should be enough, but apart from looking through it for nostalgic purposes, I think it is often too general with regard of topic discussion, and it seems to have at least some mistakes (for example, a few days ago I found a discussion on transposition tables, where the ps...
by Gerd Isenberg
Fri Feb 19, 2021 8:23 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: How to make movelist using bitboards
Replies: 32
Views: 3373

Re: How to make movelist using bitboards

BTW ~bits + 1 is also known under the name -bits (2-complements system). Two's complement as increment of the ones' complement is quite obvious. Adding something to its ones' complement leaves all bits in a word set. Adding one overflows to zero. (x + ~x) + 1 == 0 I wonder why there were some ones'...
by Gerd Isenberg
Fri Feb 19, 2021 7:30 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: How to make movelist using bitboards
Replies: 32
Views: 3373

Re: How to make movelist using bitboards

Sorry. I do not catch the idea. Not how to do it (that is what I feel you tried to explain me), I do not know what I need to do it! :P Soberango go piece by piece and move by move and test if it is allowed or not. Now I understand how to know all the moves that each piece could do. What is the idea...
by Gerd Isenberg
Fri Feb 19, 2021 5:04 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: How to make movelist using bitboards
Replies: 32
Views: 3373

Re: How to make movelist using bitboards

Converting target squares of a bitboard into a list is referred as Bitboard Serialization in CPW. The necessary bit scan might also be done without special bsf, aka trailing zero count instruction (using compiler intrinsics for X64 or ARM ), but portable and quite efficiently by Multiplication of th...
by Gerd Isenberg
Tue Feb 16, 2021 9:10 pm
Forum: Computer Chess Club: General Topics
Topic: Advantage of using bitboard lookup tables to generate moves?
Replies: 3
Views: 661

Re: Advantage of using bitboard lookup tables to generate moves?

Possibly noob question: It seems everyone is using bitboards combined with look up tables to generate moves. While I understand that for things like "is this square occupied" bitboards are great, I don't quite see the advantage of using them for move generation. For example, if I have a rook I can ...
by Gerd Isenberg
Mon Feb 01, 2021 8:31 pm
Forum: Computer Chess Club: General Topics
Topic: So what do we miss in the traditional evaluation?
Replies: 29
Views: 6336

Re: So what do we miss in the traditional evaluation?

From ML perspective it gets even more clear - HCE can only handle linear dependencies between static eval and results while NNUE thankfully to it's hidden layers is capable of revealing non linear dependencies, e.g. non-deterministic behavior in similar positions. Nonlinear dependencies have nothin...