[GRASS-user] measuring area on a 3d polygon

[maning sambale]

Hi,

I have a series polygons located in a mountainous terrain.  I can
convert the 2d vector into 2.5d using v.drape and a DEM, however, it
only converts 2D vector point or line data and not areas.  My task is
to calculate the area in hectares of the polygon incorporating the
elevation/surface of the polygon.  I then need to subdivide the main
polygon into smaller polygons using a preferred area in hectares.

How to calculate 2.5d polygon areas in grass?

-- 
cheers,
maning
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