World Draughts Forum

Codex is currently implementing 'slice by man row'.

GW

BTW, you should already be able to generate 4 kings vs 4 kings and 5 kings vs 3 kings with the current version.

GW

Saying goodbye to these formulas I derived years ago to calculate a reasonably compact EGTB index with holes..

#define SUM2(L0) (((99 - L0) * L0) / 2)
#define SUM2M(L0, M) (((2 * M + 1 - L0) * L0) / 2)

#define SUM3(L0) (((7202 - 147 * L0 + L0 * L0) * L0) / 6)
#define SUM32(L0, L1) (((1 + L0 - L1 ...

I don't have the job logs any more but in my email history I found that calculating the 81 slices (9x9) for the 3 kings and 1 man vs 1 king and 3 man EGTB already took two-three months. At that time only the (slices of) the EGTB being generated fitted in RAM and SSD, so I had to move the slices to ...

So 1+1 = 3 again here. Generating 3 kings vs 3 kings was about 7 times slower than my OpenMPI code, so I told Codex to use the compressed flat-files that are incrementally updated during EGTB generation and compiled into the final EGTB before validation that my OpenMPI code used. That alone already ...

I will check if I still have the log from the generation of one of these databases to see how long that took. I found an example position in my email history:

.. .. wX .. bO
.. .. .. .. ..
.. .. bX .. ..
.. .. .. .. ..
.. .. .. .. ..
.. .. .. .. ..
.. wO .. .. ..
.. .. .. .. wX
.. .. wX ...

Hi,

Years ago I developed an OpenMPI based EGTB generator that in principle could also generate 8-piece DTM EGTBs by partitioning the EGTBs by (man)rows. I generated a couple of 8-piece EGTBs but in the end it took too much time.
GWD uses a ZSTD page-compressed representation of the EGTB: each ...

Hi,

Version 2.22 is now available on github: https://github.com/gwiesenekker/GWDGUI/releases/tag/v2.22. The 'game tree' should be the 'source of truth', meaning you should be able to click on running games, PVs, browse games, browse PVs without crashing the GUI because it maintained a state outside ...

Hi,

GWD uses a (hardware) CRC32 checksum to validate the integrity of the (lockless) TT entries. It turns out that you can store the CRC32 on top-of the standard two 64-bit unsigned-integers that GWD uses for a TT entry, so you do not need an additional 32/64 bit integer to store it. 1+1=3: I got ...

Hi Bert,

What are the results if you use 1 minute/75 moves? If I use 5 min/80 moves GWD draws all the time against Kingsrow, with 1 minute/75 moves sometimes GWD loses a game (but also sometimes wins).

GW

Hi,

Although generally speaking you should not evaluate positions with a neural network that are 'far off' from the positions the network has been trained on it is quite instructive to evaluate the following 'sparse' positions with your NN including the empty board:

W:W:B {0.0}
W:W6:B {0.0}
W:W7:B ...

Hi Bert,

Interesting. Were the patterns suggested by Codex? In GWD I get the best results with the 8 '6x4' (12 squares) overlapping men-only patterns: 01 02 06 07 11 12 16 17 21 22 26 27..04 05 09 10 14 15 19 20 24 25 29 30..21 22 26 27 31 32 36 37 41 42 46 47..24 25 29 30 34 35 39 40 44 45 49 50 ...

Hi,

I have been testing floats rather than ints for the evaluation in GWD. As GWD uses embedding vectors for the evaluation of the neural network GWD no longer needs NNUE and evaluation using floats is just as fast as ints.
The idea was to add the material-balance 'behind the comma' to the ...

Hi,

Automatically generating documentation from the source code (and the chat) is of course no issue. I cannot attach a .md file, so I copy/pasted the contents below.

GW

# GWDGUI User Manual

This is a first-version manual for the current GWDGUI application. GWDGUI is a
graphical workbench for ...

Hi,

The game tree as the source of truth seems to be working now. I will try to add Auto Play again, perhaps the new version of Codex gets it right and then I will publish the new release.

GW