[boost] Preview 4 of the Generic Geometry Library (ggl)

Subject: [boost] Preview 4 of the Generic Geometry Library (ggl)
From: Barend Gehrels (barend_at_[hidden])
Date: 2009-02-17 06:59:00

Dear list,

It is a pleasure for us to present the fourth preview of the Generic 
Geometry Library.

This time we've added the library to the SVN repository at boost, 
https://svn.boost.org/svn/boost/sandbox/ggl

To store the library under a proper name, "ggl" is used, which stands 
for Generic Geometry Library. Before this we called it just Geometry 
Library, but we think Generic is appropriate from this version on.

The first three previews were sent to this list in January, March and 
October 2008. Since then everything has been revised and reworked again, 
based on comments from the list. Thanks for all your comments!

Concepts are now applied for all geometries. Algorithms now take any 
geometry fulfilling the concepts, and automatically take the right 
version of the underlying implementation. Ranges are now used instead of 
.begin()/end(). Tag dispatching is used instead of SFINAE.

Transformations: previously these were just explained as an example, now 
  transformations are included in the library, either to go from one 
coordinate system to another (for example from spherical to cartesian3D) 
or to translate/rotate/scale/map points from one Cartesian system to 
another, or otherwise.

Map projections: included is an extensive addition with nearly 100 map 
projections. Those are not programmed by ourselves but automatically 
converted from C (PROJ4) into a our template-based approach, fitting 
with the geometry library, especially in the transformations explained 
above. License-wise this is possible. We're not sure about if this would 
fit in the Boost Library Collection, if there is interest in it, or that 
it might be "too much" for it, so we would be glad to hear your opinions.

For more change descriptions, see the page on status and preview from 
the documentation (link below).

The Generic Geometry Library is accessible from Boost SVN, mentioned 
above, or can be downloaded as well from http://geometrylibrary.geodan.nl

Especially the examples, such as the custom point example and custom 
line string example show nicely how the library handles custom 
geometries and how they can be used inside the generic algorithms.

We welcome any type of comment, opinion, cooperation, merge or join.

Barend Gehrels, Amsterdam
Bruno Lalande, Paris