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30. November 2021, 01:47:30
Subject: Backgammon with Doubling Cube (quick tournaround)
There are a lot of tournaments offered right now, but I prefer to play *with the doubling cube*.
If you do too, and you like a fast game, please join here!

19. October 2021, 14:50:28
Subject: Re:
Modified by Aganju (19. October 2021, 14:53:06)
moistfinger: Your idea is correct. I HAVE doubled from the bar before, not often, but not never either. It is a good play in some situations.
I wouldn't want this option to be taken away...

Note that if you CANNOT double (because the opponent has the cube, or it's post-crawford), it DOES Autopass.
So it is not an be-lazy-and-save-some-code-problem, in the contrary, it is doing it even more detailed and correct.

5. May 2021, 01:23:18
Subject: Re:
Walter Montego: I just looked at the game that was listed - I do not see them either. this is worse than I thought; I agree it is unplayable. I have never seen that in any of my games, which is strange - I played hundreds f Plakotos, with the same size setting. Could it be the *color* choice?

4. May 2021, 14:28:03
Subject: Re:
Modified by Aganju (4. May 2021, 14:28:38)
rod03801: my guess is that a specific image is missing. If you look at the board where there is a blank, right click it, and it will give you the name of the (missing) image. This would make it a twenty-second fix for Fencer.

20. August 2020, 14:26:15
Subject: Re:

19. August 2020, 18:32:58
Subject: Re:
pgt: looks like a nasty bug... contact Fencer in a personal message and ask him nicely, he might just fix it.

And in the future, don't roll 4-4 when you have only 1 checker left - it's a waste anyway... ;-)

9. June 2020, 19:11:35
Subject: Re: Am I missing something?
Modified by Aganju (9. June 2020, 19:13:05)
After hitting him with the 3 (which I understand you'd love to do), you would not be able to play the 5 anymore.
The official backgammon rule says "you have to play both dice if possible, and if you can play only either one, you have to play the higher one" - in this case, the 5.

The rules on this site also list this, towards the very end:
"If it is possible, both dice must be used. It means that some pieces can become "frozen" in certain positions because making a move with these pieces would create a situation where the second dice couldn't be used.
If only one die can be used, the one with the higher number must be chosen.'

Too bad, but according to the rule...

27. January 2020, 02:50:20
Subject: Re: I wonder.
Carl: you said that, not me.
I said it looks like he is not any good, as I looked at some older games, and he played not exceptional. All newer games show that they were resigned by the opponent after two moves, which looks rather fishy.

But it is well known that there are cheaters around here. Some people get off on arbitrarily raising their ratings by having multiple accounts and pumping points between them. I feel sorry for them, I hope they see a psychologist some day about it.

27. January 2020, 00:27:37
Subject: Re: I wonder.
Carl: looks like he is not any good, just uses a second account to pump up his rating.

3. April 2019, 00:33:43
Subject: Re: Double rolls..
Nothingness: the quality of random numbers here has been discussed before, and there may be issues with them, or not.

However, rolling 7 doubles in a row has a chance of about 1:280000, meaning it is completely normal (and to be expected) that it happens once per 280000 tries.
If you consider that a Backgammon game has about 30 moves per side, and assume about 5000 games are played per year on Brainking, it should happen every other year.
So as annoying as it might be to lose that way, it is not necessarily a sign for something off - it should happen every other year.
Let's hope it doesn't hit you (or me) this year.

26. December 2018, 22:12:36
Subject: Re: gammon not working?
happyjuggler0: right, thanks. I missed that little detail, just saw it's a 'match to 7 points', not '7 wins'. But as you pointed out, Gammons and Backgammons don't count here unless the doubling cube is used.

26. December 2018, 14:44:08
Subject: gammon not working?
Why would I not get a Gammon (2 points) for this game??
Backgammon (Geomomo vs. Aganju)

22. November 2018, 00:40:58
Subject: Re: Proper functionality
AlliumCepa: I had no idea who you are, and your post sounded like the whining of a newbie - you wrote: "Whoever runs this site now, can you explain please?". So i assumed you have no idea, and tried to explain it to you:
Fencer still owns the site, and he doesn't owe you (or anyone else) an explanation, or a bug-fix.

If you contributed something voluntarily in the past, it was your free decision, and although I appreciate it, _I think_ it doesn't entitle you to whining, or earned you the right to complain.

"Whoever runs this site now, can you explain please?" is not _trying to help_, it is requesting something you think you are entitled to. You can ask that to if the gadget you bought doesn't work.

But if you want, feel free to continue to request answers. Fencer is still the right person to complain to. I recommend you use the bug reporting site, or the tournament site, not the backgammon site, as your issues sees unrelated to backgammon. And you can contact Fencer with a personal message, and he typically answers those.

21. November 2018, 15:10:11
Subject: Re: Proper functionality
AlliumCepa: Alliumcepa, if you read the posts, nobody specifically runs the site. The server is kept running, Fencer monitors the server, and still owns it. Note that it's free, it comes without any guarantees, and it's use-as-you-find-it. If you don't like it, you get your money back (meaning nothing) and you are free to play somewhere else.
Please don't feel entitled to anything else just because you paid nothing to use it and found it on the internet.

20. May 2018, 21:12:29
Subject: Re:
Modified by Aganju (20. May 2018, 21:12:50)
Clandestine 1: here is one that ended about 7 hours *before* it started: ultrabrain. That is speed!

23. March 2017, 01:59:54
Subject: Re: thanks for not finishing your game jerk
Francine2_49: whom do you mean? is his name Jerk??

11. November 2016, 20:35:46
Subject: Re: cloning backgammon final piece...
Modified by Aganju (11. November 2016, 20:36:10)
speachless: in standard Backgammon, the rule says if you can move both dice (instead of only one) you MUST do so. Of course, in a situation like this, this would be always be to your advantage (or wouldn't matter).

Assuming that the base BG rules are not changed for Cloning - except as described - this would still be part of the rules, so you MUST hit, sorry. That would be my interpretation of the rules.

30. October 2016, 21:19:35
Subject: Re: Magical appearance of 15 more pieces !!?
speachless: well I wouldn't care if they are simply _not displayed_, but the pip count should know about them - that is a significant decision point in making it a run game.
Now I can only hope hat my opponent is up for the same surprise in some moves...

30. October 2016, 20:28:04
Subject: Magical appearance of 15 more pieces !!?
Cloning Backgammon (TC vs. Aganju) and
Cloning Backgammon (TC vs. Aganju) - I suddenly have 15 pieces more!?

7. September 2016, 14:36:43
Subject: Re: Fevga - Rule Question
playBunny: Thanks!
I tried to trick BK by typing the double-move into the URL, but it did not execute the move, so it is explicitly checking the intermediate positions for legality.
As that situation would be quite rare, maybe even most real-live players have never encountered it and wouldn't know the rule exactly.
I guess it was inconvenient, but it will not make me lose the game. I just found it interesting.

4. September 2016, 20:28:59
Subject: Fevga - Rule Question
Modified by Aganju (4. September 2016, 20:29:52)
In this game , I (black) rolled a 5-5, and I'd like to move 12-7, 12-7 (plus something else), but the system doesn't allow this (you are not allowed to block all 6 spots in your home). However, i am not really blocking them as at the end of my move, the ace is free again.

The question is: Do the rules mean that - 'not even temporarily", or is it a bug? Who knows Fevga well enough in the real world?

28. February 2016, 17:21:59
Subject: Re: Disappearing points in Plakoto
Modified by Aganju (28. February 2016, 17:22:53)
stargood: i had that sometimes over the years. It is just an image display issue, and has no effect on the game itself (aside from that you cannot see how many pieces are stacked up).

If you go to another computer/smartphone, the problem is typically gone; you might be able to resolve it by flushing your buffers (use CTRL + F5 on a PC), or purging the cache (depending on your browser).
It could also be that the image server currently has an issue with this file.

P.S. I can also see your pinned pieces.

20. March 2014, 12:20:25
Subject: Re: Cloning Backgammon Error
speachless: I don't see a reason why bar-5-7 would not be a perfectly legal move for white.

14. March 2014, 19:21:36
Subject: Re: Fevga rule
Carpe Diem: i think it should be interpreted 'if you cannot move any more with any dice roll, he needs to open up'. But I have never played Fevga over a real board, so maybe someone who has should answer this.

30. December 2013, 02:12:32
Subject: Re: The terrible RNG
playBunny: You are right of course. It does not make it easier to win, if you cannot predict the 'bad' rolls. However, if the randomness is not good, it slowly makes a different game out of Backgammon - for example, if there are less doubles, or incorrectly often two doubles in a row, you can adjust your strategy to take advantage of it. It is still a fair game, but it is not 'standard' Backgammon anymore.

However, I found a high chance of reproducing your opponent's roll by clicking in specific sequences. So when the game comes up, and he had a 5-5, and I want one too, I do that sequence of clicks, and have a higher-than-1/36 chance to get it too (it does not work all the time, but maybe 1:3; still, pretty useful feature); whereas if he has 1-2, I will not do that typically.

27. December 2013, 04:25:33
Subject: Backgammon Tourneys
Modified by Aganju (27. December 2013, 04:26:11)
It seems the majority of people create Backgammon tournaments with the setting '1 win match', be it in round-robin or 1-1 play. That may be the best way for most games, but for BG I think the better choice would be at least '5 points with doubling cube' or even higher.
The reason is that BG has a significant factor of luck, and even as the world champion, you could lose a match against Joe Schmoe if the dice roll unlucky - but not so easily a match for 5. Whatever, anyone who seriously plays BG, knows what I talk about.
For me, this discourages me from joining any of those tournaments, especially when they are 1-on-1, as it is mostly luck deciding who wins the tourney.

Here my question: Am I alone with that opinion, and all others are happy with how they are offered?
if yes, then fine. I can always make tourneys the way I prefer them if I want. No hard feelings.
If no, then I wanted the tournament creators to know that; so they can create them as '5 point with doubling' (or more) and get more players. Maybe they are just not aware of it?

4. December 2013, 03:33:52
Subject: Re: Pieces on the bar in Crowded Backgammon with the double cube being used
Walter Montego: oh, and Fencer has mostly stopped caring about issues and bugs (and wishes) on this site. He might fix it if he feels in the mood, but chances are small. A lot of people have already discussed that and attacked him for it, but well, that is his decision, and this site is not a priority for him.

4. December 2013, 03:30:08
Subject: Re: Pieces on the bar in Crowded Backgammon with the double cube being used
Walter Montego: both games have in common that there can be pieces on the bar that you don't have to insert immediately, but can whenever you want. Those are the ones that have the bug.

4. December 2013, 02:17:50
Subject: Re: Pieces on the bar in Crowded Backgammon with the double cube being used
Walter Montego: it is a known bug. If the pieces on the bar are 'extra' pieces and not pieces you hit earlier, the system does not consider them for backgammon (not even for gammon).
The same happens in Cloning BG, when you hit someone and get an extra piece on your bar - it does not count against backgammon or gammon.

9. June 2013, 02:47:55
Subject: Re: Never ending game?
furbster: I had one of those a while ago, we agreed on a draw. The system does not recognize that neither party can make moves anymore.
Of course, nobody can force them to make a draw, and old age will decide the game one day.

25. March 2013, 01:59:47
Subject: A 9-prime - is that a record?
I didn't manage to make the 10-prime, but anyone had a 9-prime before?
Crowded Backgammon (Rainbow Days vs. Aganju)

28. February 2013, 23:23:59
Subject: Re: Hopefully
Hrqls: I am here 18 months only, and I have already won 32 backgammon tournaments (and 159 in total). One of them was a 21-point round-robin.

It really depends a lot on which tournaments, and who is in there. There are about a dozen players you should avoid, without them this tournament would have been done in two to three months; but a single one of them is enough to drag it to 5 years.

9. February 2013, 04:40:38
Subject: Re: Grasshopper
speachless: Yes it's a draw. I had one a while ago. The system does not recognize it, so if your opponent doesn't agree, it goes one forever...

18. October 2012, 03:06:44
Subject: Re:
Resher: I guess that would work, but I think it is a bug, and a funny one.

17. October 2012, 23:04:34
I am in a Grashoppers game where bth players cannot make moves anymore (5774462), but the rules have no plan for it, and neither has the server. So we are stuck in an infinite game!

13. October 2012, 14:36:42
Subject: Re: Lots o' fives
playBunny: I think you misunderstood me. Of course, seeding every time as well as seeding only with the minutes is not a good idea; this was my try to reverse-engineer the experienced behavior here on BK. As I wrote below, if I play a move in five games within one minute, all my opponents have the same roll afterwards. That seems to point to
a) the roll for the opponent is made the moment I send my move, and
b) the minute is used for seeding every time,
so that would explain why they all have the same roll. That's only a guess, of course, but one that explains what's happening.
Because all my opponents answer at different times, typically this is not very obvious, but if you note it down, you can check the games and verify that they all roll equal.

A good (pseudo-)random number generator consists of multiplying a stored number with a large prime, and dividing by another large prime, the division result is stored for the next round, and the division rest is normalized to be used as the 'random' number. The quality and equal distribution of the resulting sequence depends on the choice of the two primes, and as part of my work, we analyzed all primes up to 1 billion for their resulting random number quality. I have kept the best result (I hope), and will look it up later and post it here.

I know that Fencer is rather good at what he does, and I know that a lot of people whined already about the random numbers here on BK, so I just gave up complaining myself. I just answered to someone else's comment about five times 5-5 in a row, and that it is unfortunately quite common to see that in opponents rolls if you play fast.

Here is the C++ code from ~2001 with the best possible random numbers for numbers below 1 billion. It will return a
double between 0 and 1, and needs to be normalized to the target interval (backgammon: 1-6).

double Rnd::Double (void)
/* Linearer Kongruenzgenerator nach Afflerbach
x[i+1] = x[i] * 27132 + 1 (mod 62748517), z[i] = x[i] / 62748517
Periodenlaenge 62748517, Beyer-Quotienten 0.969, 0.922, 0.819
Bestmoegliche Verteilung fuer Modul m <1e9 */
static unsigned long xi = 0;
int i;
unsigned long z = 0;

if (xi == 0) xi = (unsigned long) time(NULL);

for (i=30; i>0; i--) {
z <<= 1;
if (xi & (1L << (i-1))) z += 27132L;
while (z> 62748516L) z -= 62748517L;
xi = z + 1L;
return ((double) xi / 62748517.0);

12. October 2012, 16:05:37
Subject: Re: Lots o' fives
playBunny: Actually, yes. Part of my masters degree was about 'Pseudo random numbers', how to make them and how to analyze the quality. It's been a while, though.

12. October 2012, 05:07:25
Subject: Re: Lots o' fives
Aganju: I think the issue is that the routine uses the current time as seed or so. If you make many moves within a minute, all your opponents get the same roll. I have started to wait a full minute before re-rolling in dice poker, and it helps a lot to get a different result.

12. October 2012, 05:04:45
Subject: Re: Lots o' fives
Modified by Aganju (12. October 2012, 05:05:11)
Walter Montego:
I often see that here. The discussion has been had a thousand times, and Fencer claims the dice-rolling-routine is good, but I cannot believe that.
I had nine of my opponents roll 6-6 in a row...
In Dice Poker, everybody can count this for himself: if you select two dice for re-roll, 90% of the time the same numbers come up again. Just countit or a while.

8. June 2012, 21:58:49
Subject: Re: plakoto backgammon errors
rod03801: I see the same, one piece each time (incorrectly).
For both board sizes.
Using Safari on iPad

17. May 2012, 05:55:45
Subject: Re:
pgt: you are right this is very strange. Send a message to Fencer, he will probably fix it.

14. January 2012, 00:28:40
Subject: Back gammon does not count triple??
Modified by Aganju (14. January 2012, 00:31:29)
In this game, I would have expected to get a 'backgammon' meaning three points, multiplied by the cube of 2, resulting in 6 points. However, I got four. Can someone explain me why?
He has not borne off anything, he has a piece still on the home bar, the doubling cube was used and accepted. So what is missing??

28. December 2011, 19:14:02
Modified by Aganju (28. December 2011, 19:15:11)
Is there a bug in site code, or do I miss something?
In Fevga game 5460931, I have collected all my pieces behind his block. The rules state:
"... If opponent has collected all his checkers onto the one point behind player's prime, the player must unblock a point in his prime to allow the opponent a chance to move..." (Fevga rules, next to last paragraph).
Still, my opponent made a move that did not unblock me - which should not have been allowed?
Am I wrong or is the code wrong?

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