Hamish,

 

Having tried r.to.rast3, r.to.rast3elev, v.to.rast3 and v.vol.rst, I can now 
create a number of G3D files showing the carbon levels, however they are only 
in planar form. In NVIZ I load the DEM file I already created as elevation and 
colour, then the DIC file as the 3D raster. After some fiddling about, it 
appears as a 2D surface on the loch (depsite error messages popping up about 
working with a scalar variable), which can be lowered or raised using the 
Position bar, however the colours stay the same. This is the first time I've 
got any of the 3D Loch Lomond data to work in NVIZ, it's just a shame it's not 
actually represented in 3D!

 

In Paraview, I load the same files and again see a 2D surface. By increasing 
the z-exaggeration I can create a second surface underneath the first one, 
showing the same interpolated carbon values, but with nothing in between the 
two.

 

Re: nnbathy, I followed the link to the Grass Add-On site but found now way to 
download the file! In any event I have a 2.5D DEM of the Loch, but thanks 
anyway.

 

The other issue I'm having is the creation of a mask for the lake. I created 
the outline of the shore in vector point form(573 points), but have tried 
multiple ways to convert it into an area or polygon with no success. Even the 
v.type_wrapper tool, which converts points, centroids, faces, lines and areas 
didn't help. This is relatively simple in ArcGIS, but I still haven't found a 
way to creat polygons in GRASS, even through v.digit, so I'm probably missing 
something obvious!
 

> Date: Mon, 26 Jul 2010 23:44:27 -0700
> From: [email protected]
> Subject: Re: [GRASS-user] Lake modelling using volume interpolation 
> (v.vol.rst and Paraview)
> To: [email protected]; [email protected]
> 
> Is the temperature & carbon in e.g. continuous vertical CTD profiles
> down through the water column, random water samples from "various" mid-water
> depths, or from bottom samples, or..?
> 
> btw, what sort of "carbon" data are we talking about? DOC levels? isotopes?
> 
> 
> if from like CTD data with hi-res in the vertical but stations being
> spaced some far distance horizontally) you can also split it up into
> a series of 2D vertical sections at each depth, run v.surf.rst for each
> one, then stack all those 2D slices together with r.to.rast3 for your
> 3D raster block.


The data is in 84 water columns with 3 measurements each - the surface, a mid 
depth then one near the lake bed. Dissolved Inorganic Carbon and Temperature 
was measured at each point. 21 columns were measured in each of the 4 seasons 
of the year, so the idea was to build up a time comparison as well.

 

Thanks for your help,

 

Craig
                                          
_______________________________________________
grass-user mailing list
[email protected]
http://lists.osgeo.org/mailman/listinfo/grass-user

Reply via email to