[no subject]

[Heikki Levanto <heikki@xxxxxx>]

To: computer-go@xxxxxxxxxxxxxxxxx
Subject: Re: Bitmaps vs Lists
Cc: heikki
Newsgroups: lsd.compgo
Organization: LSD - Levanto Software Development
X-Newsreader: TIN [version 1.2 PL2]

Philipp Garcia (pgarcia@xxxxxxxxxxxxxxxxx) wrote in lsd.compgo:
: Do you use bitmap or list type structures in "objects" (term used loosely)
: to represent strings, blocks, liberties lists, etc?

I have been playing with many ideas (and never got further :-)

The most recent one involves a heavy use of bitmaps. I can do the whole
board mechanics (capture etc) with whole-board bitmaps, without even a
concept of strings.

The core of my bitmap ops is a 'shake', that ORs a bitmap to itself shifted
left, right, up, and down; and of course a simple mask (x = x AND NOT y);
finally a loop repeating these two, until the result is stable, for flood
filling.

I have no idea of the speed of this approach yet, but at least it is
different. I will keep studying it (and the Java language - the main purpose
of the project) to see how far I can get with pure bitmaps. Strings are
easy, I believe I can handle some sort of links, and probably also larger
scale grouping, with influence and potential territories... If I get to some
conclusions, I will report here. But don't hold your breath, this is just a
study project, and time being I'm busy working.

 - Heikki Levanto
   5k player and dan-level programmer


--
Heikki Levanto  LSD - Levanto Software Development   <heikki@xxxxxxxxxxxxxxxxx>