cheg01 wrote: > faces are to be understood as "3D areas", their centroids are "kernels". > yes, v.extrude generates only faces
One thing I have never understood: do kernels live on the surface of a 2D plane in 3D space (so 6 per cube), or inside a volume (the center of a sphere)? > > I tried extruding both > > with and without the "trace" flag set. Jachym wrote: > this only causes, that the "roofs" of building will "copy" the > elevation. Otherwise, they remain flat. going back to the earlier thread, I had an idea to remove buildings from the LIDAR raster data. Make a slope map, set anything with >60-80 degree slope as NULL. (take away the walls) Next use r.cost starting on known land to isolate the roofs which do not touch the land, use the cost map as a MASK and make a layer with only land. Then use r.fillnulls or similar to interpolate over the holes leaving a elevation surface with no buildings. ? Hamish __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com _______________________________________________ grassuser mailing list grassuser@grass.itc.it http://grass.itc.it/mailman/listinfo/grassuser