Path: chuka.playstation.co.uk!news
From: Steve Parnell <S.Parnell@Bradford.ac.uk>
Newsgroups: scee.yaroze.programming.2d_graphics
Subject: Re: Path Finding / Collision Detection
Date: Thu, 10 Dec 1998 13:01:09 +0000
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Hi,

I think basically 3 reasons:

1: Hexagons tessellate a plane, octagons etc don't.
2: Because of this, hexagon maps can easily be transformed to a regular 2D
square grid and stored in a 2D array.
3: The centre of each of a hexagon's 6 neighbours is the same distance from
the central hexagon's centre. This is useful when calculating next moves from
one cell to another, as each step will be the same distance. In a square
representation, a step to a cell at a vertex costs more than one at an edge
(by a factor of sqrt(2) in fact!) and this complicates things when
calculating the best route from A to B. Anything non-tessellating complicates
it even more.

Any more than this are beyond my limited intelligence :-\
I've always wondered whether a monitor with pixels on a hexagonal grid would
help cut out jaggies and whether we humanoids are so fixed by the square grid
that we're missing a point somewhere that bees sussed out aeons ago?

Steev


Antony Arciuolo wrote:

> Just a quick question...
>
> Why are hexagons commonly used in RTS games and in algorithms such as A*?
> I'm not well-versed in the algorithm, but it seems to me there are no
> horizontally-adjacent hexagons (at least not across a side). And if it
> doesn't matter whether the surrounding hexagons are surrounding by their
> sides, or by their vertices, then again, why especially hexagons, why not
> octagons?
>
> - Tony