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: Simonson, Lucanus J (lucanus.j.simonson)
Date: 2011-09-24 13:17:21

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/f9a6ec4b/attachment.html