[GRASS-dev] wxNviz volumes

[Helena Mitasova]

On Jul 2, 2011, at 7:35 AM, Anna Kratochvílová wrote:

> Hello Helena,
> 
>>>> - I tried volumes in wxnviz but I did not get too far - the GUI does not see
>> any
>>>> of my 3d rasters -
>>>> the browser for 3D raster maps shows the mapsets but nothing in them
>>> 
>>> It should be ok now.
>> 
>> It still does not work for me - when I am setting the 3D region (from set region
>> to match this 3D raster) they show up,
>> but not when I try to add it under wxnviz>Volume. Am I missing something? Should
>> I be adding them as map layers 
>> first somewhere?
> 
> 3D raster must be loaded from the layer manager toolbar first like any other maps do. 
> In wxnviz only loaded maps (in Map layers tab) are offered. You tried this and it still doesn't work?
> Maybe I'm missing something.
> 
> I was able to find just the Slovakia3D dataset. Could you tell me where I can find any other volumes
> for better testing?

I am working on a new one but I got into some troubles when I tried to extend the data set and use mask.

Meanwhile you can try this:
get this raster time series mapset and put it into nc_spm_08
http://courses.ncsu.edu/mea582/common/media/01/NagsHead_series.zip
then generate a space-time cube representation of the time series for a small subregion:

g.region n=250416 s=249942 w=913734 e=914022 t=40 b=12 nsres=2 ewres=2 res3=2 tbres=4 -ap3
r.to.rast3 in=NH_1999_1m,NH_2001_1m,NH_2004_1m,NH_2005_1m,NH_2007_1m,NH_2008_1m out=NH_99_08_stack
#check your values
r3.info NH_99_08_stack

you can then use elevation raster NH_2008_1m in combination with with NH_99_08_stack 
to test everything for a single volume (isosurfaces 6, 10, 12 work well)

to generate second volume for testing over little bit larger area (I had to quit grass when changing
computational region because the 3d view was stuck with the previous region and I could not find a way
to get it to update to the new region)

g.region rast=NH_1999_1m t=40 b=12 tbres=4 -p3
r.to.rast3 in=NH_1999_1m,NH_2001_1m,NH_2004_1m,NH_2005_1m,NH_2007_1m,NH_2008_1m out=NH_99_08_largestack
r3.info NH_99_08_largestack

you can then use NH_2008_1m in combination with with NH_99_08_stack and NH_99_08_largestack
to test handling of two volumes. You will note that whichever volume you you have loaded a second one,
it will draw the isosurfaces in black - I think they are not illuminated.

Let me know if something is not clear, it is still a little bit tricky but it works,

> I would like to ask if the new feature - generating commands for nviz_cmd is ok or if the interface should look 
> differently (where the output should be written etc.). So if you have some ideas please tell me.

it is good as is right now, I think users can write scripts on their own to run the command through series 
of raster maps to generate the dynamic surfaces. Of course, GUI would be helpful but I would leave it after
wxnviz core functionality runs well. 
One issue came to mind when looking at the command (I think this was already discussed before) - would it be possible
to replace the ppm output with png or other more common format?

Helena
> 
> Anna