[GRASS-user] r.out.pov scale question

[Adam Dershowitz, Ph.D., P.E.]

Thanks.  This is helpful for some ideas.  
Although, it uses a vertical scale that is just a constant of 65535.  But, my followup email probably crossed with yours.  



--Adam



On Nov 3, 2010, at 4:22 AM, Markus Neteler wrote:

> Adam,
> 
> find attached my (old) r.out.povscript script which does the needed
> calculations. Perhaps
> giving some ideas. the Povray scales are a bit tricky.
> 
> cheers
> Markus
> 
> On Wed, Oct 27, 2010 at 6:07 PM, Adam Dershowitz, Ph.D., P.E.
> <adershowitz at exponent.com> wrote:
>> I have been trying to use r.out.pov but something is not clear to me from the documentation, and examples I can find on the web.
>> If I use hftype=0 (the default) then, as I understand it it, each step, from 0-65535 represents one map unit (meters in my case).  That is giving me too much "stair-stepping" in POVRAY.
>> I think that part of the issue is that there is too much rounding of elevations.  So, I decided to try hrtype=1.  As I understand it that will scale the height of the image to use more of the range (my map just goes from 61-1086 meters).  But, I can't seem to figure out how much it scales by.  There is also the scale= option in r.out.pov, but I am not sure if that is a multiplier or a divider?
>> This is important because I need to then scale the heighfield in my POV file.  If I use hrtype=0 then this is correct:
>> scale < dx, 65535, dy >
>> 
>> But, if I use hftype=1, what is the correct value for the above scale command?  Is it 65535/1086 (max height in the map?)
>> 65535/(1086-61)  (vertical range of my map?)
>> 
>> If I use scale=10 then should it be?
>> scale < dx, 65535/10, dy >
>> scale < dx, 65535*10, dy >
>> scale < dx, 10, dy >
>> 
>> Or should I use scale=0.1?  Or should I use r.out.pov scale=65535/1086
>> 
>> Thanks,
>> 
>> --Adam
>> 
>> 
>> 
>> _______________________________________________
>> grass-user mailing list
>> grass-user at lists.osgeo.org
>> http://lists.osgeo.org/mailman/listinfo/grass-user
>> 
> <r.out.povscript>