RE: Using GnuBG to test own bot

[Ian Shaw]

Hi Daniel, 

There is a mechanism for using GnuBg to plug in another playing engine, but 
I've no idea how it works or even whether it has been implemented other than 
the setting being available.  You can find it in the GUI under Settings, 
Players, External. 

set player external  - Have another process make all moves for a player
Usage: set player <player> external <filename>

I don't know what the file is supposed to contain.


There are no recent bot competitions, and the formats there used to be were of 
such short duration that there was nothing meaningful to be gained from the 
results. Frank Berger took BGBlitz to some, and he reads sees this forum, so 
maybe he can give you some information. You need to play thousands or millions 
of games to distinguish between the bots, because they are all so similar in 
strength, and that doesn’t fit well with formal competitions. 

The strongest current bots, ranked by public perception, are:
1. Extreme Gammon (XG)
2. GnuBg
3. BGBlitz by Frank Berger. 

Older bots such as Snowie and Jellyfish are no longer underdevelopment, and I 
understand XG is headed the same way. I'm not aware of any other bots that 
approach these five in playing strength.  Snowie is about as string as GnuBG. 
Jellyfish is older and weaker than the other four. I think older bots such as 
Tesauro's TDGammon and others are significantly weaker than these five.

My personal view is that if XG is stronger, it is by very little. It's main 
advantages are that people many prefer the GUI, and that it is faster for 
evaluations and rollouts. I think it has some inherent design advantages in 
that it was designed for multi-threaded operation. GnuBG was designed before 
that era, so the multi-threaded features have been retro-fitted, for example, 
use of SSE and AVX instructions, multi-threaded rollouts. 

I hope this helps. (I'm not one of the developers; I've just been lurking here 
a long time.)
Ian Shaw


-----Original Message-----
From: bug-gnubg-bounces+ian.shaw=riverauto.co.uk@gnu.org 
<bug-gnubg-bounces+ian.shaw=riverauto.co.uk@gnu.org> On Behalf Of Daniel 
Lidström
Sent: Monday, August 7, 2023 9:49 AM
To: bug-gnubg@gnu.org
Subject: Using GnuBG to test own bot

Hi

Is it possible to use GnuBG to test an own implementation of a bot? I’ve been 
looking for up-to-date info on backgammon programming but haven’t found much. 
Most sources are old. Where can I find current info? For example, which 
programs are competing nowadays. Which are strongest? Are there active bot 
competitions?

/Daniel