Re: [boost] [GTL] redesign checked into sandbox

From: Phil Endecott (spam_from_boost_dev_at_[hidden])
Date: 2008-05-10 12:46:26

Simonson, Lucanus J wrote:
> Given my proposed operator syntax for so-called Boolean operations I
> could fold the arbitrary angle geometry provided by Berend's library
> into mine (or visa-vera.)
>
> manhattan + manhattan => manhattan result type by way of manhattan
> algorithm
> manhattan + 45-degree => 45-degree result type by way of 45 degree
> algorithm
> manhattan/45-degree + arbitrary angle => arbitrary angle result by way
> of arbitrary angle algorithm

As I recall, with Barend's library if you ask for the intersection of 
two unit-squares (0,0,1,1) and (1,0,2,1) you'll get a line (1,0,1,1), 
since it considers all points on the perimeter of a polygon to be 
included in the polygon:

+-+-+
| | |
+-+-+

Luke, what does your library do in this case?  I mention this because, 
as well as the C++ language style issues which I'm pleased to see are 
being discussed by smarter people than me, there are no doubt very many 
geometry-related design choices here.  If your library were 
stand-alone, your choices wouldn't matter much; but if as you suggest 
it can integrate with other (future) libraries, then consistent choices 
are needed.

Phil.