Geometry Boost List: [ggl] How can I get the equivalent of GPC tristrips?

Subject: [ggl] How can I get the equivalent of GPC tristrips?
From: Wayne Wall (tww)
Date: 2011-09-24 13:20:07

Luke,

 

Thanks for the quick response.! I'll investigate your suggestion further.

 

Wayne

 

From: ggl-bounces_at_[hidden] [mailto:ggl-bounces_at_[hidden]] On
Behalf Of Simonson, Lucanus J
Sent: Friday, September 23, 2011 2:12 PM
To: Generic Geometry Library Discussion
Subject: RE: [ggl] How can I get the equivalent of GPC tristrips?

 

Wayne,

 

I just checked with Barend, and this feature does not exist in
Boost.Geometry.  However, the feature does exist in the Boost.Polygon
library.

 

If you create a Boost.Polygon polygon_set_data<int> from your polygons and
call the get_trapezoids() function you should get exactly the tristrips you
are looking for.  Please see the Boost.Polygon documentation to get you
started.

 

Regards,

Luke

 

From: ggl-bounces_at_[hidden] [mailto:ggl-bounces_at_[hidden]] On
Behalf Of Wayne Wall
Sent: Friday, September 23, 2011 5:23 AM
To: ggl_at_[hidden]
Subject: [ggl] How can I get the equivalent of GPC tristrips?

 

I'm migrating some code that uses the Univ of Manchester GPC library to use
boost::geometry instead.  So far, it's been going well.  The old code makes
extensive use of the GPC "tristrip" decomposition capability, which is very
useful when exporting complex polygons to graphics file formats (such as
AutoCAD DXF) which can only handle simple convex rings.  It's not clear to
me how I can decompose an arbitrarily complex polygon into a spatially
equivalent collection of convex rings using boost::geometry operations.  Any
advice would be greatly appreciated. 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.osgeo.org/pipermail/ggl/attachments/20110923/45f78770/attachment.html