RE: [Bug-gnubg] GnuBG bug

[Ian Shaw]

> -----Original Message-----
> From:  Joern Thyssen
> Sent: 12 May 2003 14:39
> To: Christophe Lanuit
> On Sun, May 11, 2003 at 07:52:00PM +0200, Christophe Lanuit wrote
> > Hello,
> > 
> >  3) I click on the black 6th column, to make 6->off, and 
> GnuBG plays 6->3
> > !!!!!!
> 
> This is the intended behaviour. Use left clicks to move left dice and
> right clicks to move right dice.
>

I've experimented with Christophe's position and agree with him that there is 
definitely something odd. It's nothing to do with  swapping the dice over, 
though, because I can get the same problem with simply right clicking.

Set up a position with just a single chequer on the 10 point, and set the dice 
to 31.

All is normal: left-clicking moves the higher die, then any click moves the 
lower die.
Likewise, right-clicking moves the lower die, then any click moves the higher 
die.

Now set the dice to 63.
In this position, clicking left..left plays 10/4/1. 
I would expect right..right to play 10/7/1, but it plays 10/7/4. A third right 
click moves 4/1.

The problem is caused because GnuBg recognizes the position after 10/7/4 as a 
valid half-move, equivalent to 10/4. It's not immediately obvious that you've 
now converted your initial move of the 3 into a 6 and you need to continue your 
move by playing the 3. The red move display is a hint but would pass the casual 
player by.
(You can see the same behaviour if the dice are set to 42.)

It can't be good to have different results of click operations just because one 
die is a multiple of the other. 
 
> Alternatively, you can disable "allow dragging to illegal 
> points" on the
> Settings->Options->Game tab, and possibly enable "show higher 
> die on the
> left" on Settings->Options->Dice tab.
> 
I always play with "show higher die on the left". (I think it's now the default 
when you install the Windows package.)