[GRASS-dev] Re: wxNviz toolbar

[Helena Mitasova]

I tried it out and it is much better now, the switching between 2d,3d worked well even after zoom
and the icons are much simpler now - 
perhaps you can put the save nviz_cmd and 3D settings 3D help buttong after Hardcopy map utility
to make it a little bit more organized by the type of functionality.

I had few small issues and one big one with z-exag.

I have a problem with z-exag set to one when it isn't actually one in real-world coordinates.
Michael, I think that z-exag should reflect the actual z-exagerration,
so that I know how much is my surface exagerrated when I am looking at it -
for example the following images have z-exag one and both are obviously greatly
exagerrated vertically - just by knowing the place it looks like z-exag
0.15 gives me a realistic topography but if you don't know the place
there is no way to know. 
http://skagit.meas.ncsu.edu/~helena/grasswork/zexag_1issue.tif
this is the DEM from nc_spm_08 and we really don't have this kind of mountains here 
(it is 10 times exagerated with z-exag=1)
http://skagit.meas.ncsu.edu/~helena/grasswork/testwxnviz_z1elev.tif

There may be other options how to handle this:
- keep z-exg as it used to be, reflecting the actual z-exageration based on the raster values
(separate handling of latlong could be added to avoid extremely low z-exag
due to different units - true z-exag could be used by computing the horizontal
distance associated with the lat/long angles defining the region displayed)
- have z-exag start as 1 (which is not very convenient for my example DEMs as you can see
because I don't get much space on the slider to give a more realistic exageration )
and provide somewhere the value of actual exageration
- have z-exag start as 1 reflecting actual exageration 1 even if the surface will look completely flat
(but this won't workif z-values range is magnitudes larger than x,y values range as for lat/long)

Hamish, how does the new setting work for you? 

Another issue that does not work very well is fine resolution setting.
The original intent was for fine resolution set to 1 to be the resolution of the original raster
(later on changed to region resolution which could be set to the rater resolution) 
to avoid artifacts in the surface due to nn resampling
http://skagit.meas.ncsu.edu/~helena/grasswork/secref_resampling.png
When adjusting the 3D view to map display zoom the resolution can get easily higher that the original
raster resolution, leading to resampling and then the surface looks like there is a problem 
with the data (there used to be lots of artifacts like this in older DEMs).
Perhaps a warning should be given to the user that his DEM is resampled and the displayed
surface may have artifacts or the 3D view just should not display anything at resolution
higher than what the DEM has.

Just a small issue - 
default size of point icon is 100 - it looks like it is in map units (100m) - I think it should be in pixels, perhaps 10?

I got wxGUI crashed twice

 - when I accidentally added a vector with 6.4 topology while 3D is open 
-if I add it when 2D is open it suggests correctly to rebuild topology and does not crash
- when I digitized area and right clicked to finish it (it might have been my problem).

I did not have a chance to test the thematic mapping, but the options look great both for lines and points.

Thanks a lot for all the great work,

Helena


Helena Mitasova
Associate Professor
Department of Marine, Earth, and Atmospheric Sciences
2800 Faucette Drive, Rm. 1125 Jordan Hall
North Carolina State University
Raleigh, NC 27695-8208
hmitaso at ncsu.edu



On Aug 21, 2011, at 10:05 AM, Anna Kratochvílová wrote:

> Hi all,
> 
> 2011/8/21 Martin Landa <landa.martin at gmail.com>:
>> Hi,
>> 
>> 2011/8/20 Anna Kratochvílová <kratochanna at gmail.com>:
>>> I suggest to change the toolbar like this: remove tools for switching
>>> pages, remove quit, the rest would be moved to layer manager (to
>>> second row of toolbars) and the icons for settings and help could be
>>> changed a little bit to differ from the GUI settings and help.
>>> 
> 
> I changed the toolbar as I wrote here.  I changed also the code
> responsible for switching between 2D/3D/digitizer so I would
> appreciate if someone could test it more.
> 
> Anna
> 
>>> Please tell me if you agree.
>> 
>> generally speaking I agree with this proposal. Martin
>> 
>> --
>> Martin Landa <landa.martin gmail.com> * http://geo.fsv.cvut.cz/~landa
>>