> The MakePrairie macro does only plane areas, but you can use trace() and the
> Reorient macros to drop grass patches on a hill and orient them along the
> terrain normals. If the terrain isn't too bumpy and if the patches are small
> enough you can get away with it.
> http://www.oyonale.com/ldc/images/lumieres_detail1.jpg
> You'll still need a lot of patches though so the texture method a la Rune is
> possibly the only way for large surfaces.
>
> G.
> --

I followed the trace() advice and ran into a problem. I use an ordnance Survey
digital map for my topography and have a GPS location that coincides with the
Landmass, this location is set for the center of my scene:

 CenS     = 197610.0310786000, 11.1000000000, -695109.5844980000

 my plan was to radiate out from this spot and place grass patches to help in
the depth of field. As you can see from the x,z coordinates using <0,0,0> as a
trace point would not work (glancing blow or some other part of the topography
might intercede), so I set two points one above and one below the terrain by
adding and subtracting 50 to the y coordinate.

   new_up = 197610.0310786000, 61.1000000000, -695109.5844980000

 new_down = 197610.0310786000, -38.9000000000, -695109.5844980000
run the trace
#local clump_position  =  trace (landmass,new_up, new_down,TraceNorm);

as a test trace between these two points you would think I would get the
original CenS value, but this is what I get:

 TraceNorm      = -0.0852216709,  0.9928279034,  0.0838452206
 clump_position = 198132.9729394691, 60.9970576631, -696949.0756293016

a difference in x of 522.9418609 and z of -1839.491131

What is it that I don't understand about trace?

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