[GRASS5] adapting locations to 57, nviz updates

Radim Blazek blazek at itc.it
Fri Nov 19 05:08:57 EST 2004

Helena wrote:
> One more issue came up as I was adding WIND3 to my old location and 
> further testing nviz
> Separate WIND and WIND3 makes it possible for user to have different 
> horizontal resolution
> for 2D and 3D - this sounds pretty incosistent and potentially messy.
> However, I can imagine a situation where I want to display high 
> resolution DEM (say 2000x2000)
> combined with some isosurfaces generated from 200x200x20 (most of the 
> time the 3D data
> density isn't anywhere close to 2D data). To be consistent with the 
> behavior of other
> grass modules (and multiple surfaces in nviz) the volume would have to 
> be resampled to
> 2000x2000x20 if we use a single WIND (which is huge). The volume support 
> allows to select higher polygon size
> putting it back to 200x200x20 but is this a desired behavior?
> So does anybody see a compelling reason to keep 3D region (including 
> resolution) independent
> from 2D region or should they be the same (merged in a single WIND) and 
> any relevant resolution issues
> should be handled by modules?
> Glynn, how does r3.mapcalc handle situation when the region defined in 
> WIND3 has different resolution
> from the 3d raster(s) used in mapcalc - is there 3d resampling?

It sounds reasonable to have different resolutions for 2D and 3D,
However, it can be still in the same file. n,s,e,w can be
the same and only the resolution will be different.
We could also add a 3D/2D resolution ratio, so that
changing 2D resolution will automaticaly change also 3D resolution
if not specified.

For example
g.region res2to3=0.1
g.region res=100 => res=100 res3=1000
g.region res=100 res3=100 => res=100 res3=100


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