[OSM-dev] [osm3d] rendering area data

[Matthias Meißer]

Hi Preet,

at the 2nd 3D Workshop in Garching we agreed all to use the forum for 3D 
related discussions. So I guess this will be a better place with the 
right audience. Just login with your OSM credentials

http://forum.openstreetmap.org/viewforum.php?id=42

bye
Matthias
(user:!i!)

Am 01.04.2012 08:49, schrieb Preet:
> Hey all,
>
> There are quite a few devs working with OpenStreetMap data in 3d and
> judging from screenshots, they've been able to do some pretty awesome
> stuff so far. I'm trying to do something similar and wanted some
> feedback, specifically for rendering area data, that is, anything that
> falls under the 'area' primitive in terms of OpenStreetMap data --
> buildings, borders, etc. I'm particularly interested in how to convert
> area/relation information from *.osm xml data into polygons that can
> be rendered (decomposed into triangles).
>
> Starting from the osm area primitive info [1], it's possible to get
> contours (ie node lists) for outer geometry and holes within the area.
> This data can then be fed into something like poly2tri [2], which is a
> lib that will triangulate simple polygons (holes can be specified
> too). The triangulated data is a mesh that can be fed into any
> renderer, like OpenGL. However, we can't assume all area data are
> simple polys; [4] shows some building geometry that's not strictly
> simple. So my main problem/question to devs that are rendering
> buildings/area geometry in 3d is:
>
> * How do you build the 3d geometry for areas that are potentially
> complex polygons?
>
> [1] http://wiki.openstreetmap.org/wiki/Relation:multipolygon#Usage
> [2] http://code.google.com/p/poly2tri/
> [3] http://i.stack.imgur.com/W8Uym.png
>
>
> Regards,
>
> Preet
>
> _______________________________________________
> dev mailing list
> dev at openstreetmap.org
> http://lists.openstreetmap.org/listinfo/dev