Re: [Bug-gnubg] Keeping multiple positions in one file

[Ian Shaw]

> From: Philippe Michel
> Sent: 03 June 2013 21:17
> 
> Do you (gnubg users in general, not specifically Michael or Ian), really
> sometimes use a "game" as a collection of independent, setup positions saved
> together ?
> 

Since nobody else has chipped in yet, I'll comment, even though I am, 
specifically, Ian.

I don't do it often, but I suspect that more people would, if they could, 
easily. 

I use gnubg for a study tool, at least as much as an opponent or match analyst. 
The ability to keep a collection of positions together is very helpful. 

For example, if you are studying holding games, it makes sense to put them in a 
collection in a single file, Cmark them, and roll them out overnight. As you've 
seen, I'm trying to study all the replies to a particular roll, and I'd like to 
keep them together so I can look at them easily without having to load a new 
file each time.

Sets of problems from a chapter of a book are another obvious candidate.

Some players, such as Timothy Chow & David Rockwell, like to look at variations 
of a position, looking at the effects of moving a chequer or two slightly. If 
you do this in a match, the rest of the match gets wiped. 

I would like to see the ability to create a variation branch of a match, so you 
could set up alternate positions as branches without destroying the main path.

The sgf format is designed to allow variations, 
http://www.red-bean.com/sgf/user_guide/index.html#variations, so the structure 
is designed; the difficulty would be in representing it in the move list. The 
best idea I've had is to implement  tree-like structure from the moves list, 
with a + symbol to click on when there is a variation available.

Player 1

+3. 43: 24/21 13/9
----set position xxxxxxxxxx 
        43: 13/9 13/10

-- Ian