Geometry Boost List: [ggl] intersection_segment...

Subject: [ggl] intersection_segment...
From: Barend Gehrels (barend.gehrels)
Date: 2009-06-25 12:35:13

Hi Chris,

> For my application, I currently only need points (I'm checking 
> intersection between roads for a specific function).
OK, that is also the most easy so will be there soon. Actually it only
needs the right dispatch.
>
> I can see an application for a linestring and/or segment output but 
> it's not implemented (or foreseen to be).
>
> BTW, what is the conceptual difference between a segment and a 2-point 
> (or 1 "segment") linestring)?
Conceptually: it is more or less the same. But the 'segment' is a
helper-geometry, not defined by OGC but by ourselves, e.g. to intersect
two segments. Where the two segments may be part of a linestring, or of
a polygon (or of a multi-linestring / multi-polygon). Or even of a box.
> Conceptually, shouln't a linestring be a vector of segments?
Conceptually: yes. But implemented is a std::vector of points, for the
obvious reason not to store the same points again and again.

Regards, Barend