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Hi(gh)!
The second tile in a series of more than 8000... it contains the
Verlegenhukflya coastal lowland with Cape Verlegenhuken, the
northernmost portion of Ny-Friesland, which in turn is a large peninsula
of Spitsbergen, the largest island in the Svalbard archipelago (see map:
https://de.wikipedia.org/wiki/Datei:Topographic_map_of_Svalbard.svg).
The first rendering attached here shows the Verlegenhuken in an overhead
view from a height of 15 kilometres; the second is a closer and lower
oblique view from 2 kms; the third one a "sailor's view" of the northern
Verlegenhuken coast 5 metres above sea level; the fourth one shows the
inner (but not glaciated - the provisional texture is meant to indicate
barren rocky ground) lowland from a pedestrian perspective looking east.
A few days ago, I learned that the second, cleaned edition of the ASTER
elevation data tiles does not (and will not in the nearer future)
include areas north of 61°N. As it is highly non-trivial to separate
land from sea ice I started looking for other sources of DEMs, even
found a series of Svalbard GeoTIFFs on the server of the Norwegian Polar
Institute (https://geodata.npolar.no/) - only to realize that 3DEM, my
standard tool for generating ASCII matrices from ASTER GeoTIFFs, is not
able to display them properly, and on the Norwegian site, there is no
hint of which software preferably to use.
Is there any fellow POVer more familiar with GIS software than me to
give me a clue?
The Norwegian Polar Institute also provides highly accurate (or at least
highly accurate looking - having never been to Svalbard, I can't decide)
topographic maps of Svalbard (and other Norwegian Arctic and Antarctic
places - https://toposvalbard.npolar.no/) - if I only had an accurate
tool to distort map sections into simple cylindrical projection! (no,
GIMP's perspective deformation tool is not accurate - at least if you're
not able to use Scheme scripts!) That would be useful not only for
determining coastlines, but also to paint textures which at least take
the distribution of tundra, rock and glacier ice into account...
So, for the time being, I have to content myself with sometimes really
ugly and artificial looking coastlines (like seen in the first image)...
Another, more POV-Ray-related question: I use a not-too-complex water
material made by Christoph Hormann (code see below)... but for real
ocean, the water is much too transparent, not even in the Red Sea the
ground at 500 metres depth would be visible. How can I make the water
more opaque?
The code:
#declare M_Water=
material {
texture {
pigment {
color rgbt <1, 1, 1, 0.5> // originally: rgbt <1, 1, 1, 1>
}
finish {
diffuse 0
reflection {
<0.03, 0.03, 0.04>, <0.75, 0.75, 1>
exponent 1.2
falloff 5
fresnel on
}
specular 0.8
roughness 0.003
}
normal
{
bozo 1.5
scale 0.0001/0.001
}
}
interior {
ior 1.34
}
}
Adding some scattering media to the interior probably might do the
trick, I think... but for the next three hours (I love these long, dark,
silent coding nights!) my computer will be occupied by generating the
mesh2 for the next tile, i. e. n80e017, perhaps I will come up with the
first multi-tile image later today!
See you in Khyberspace!
Yadgar
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Attachments:
Download '2020-04-11 povearth, svalbard, verlegenhuken, take 1 - overhead view from 15 kms.jpg' (41 KB)
Download '2020-04-12 povearth, svalbard, verlegenhuken, take 3 - view from north, 2 kms above ground.jpg' (257 KB)
Download '2020-04-12 povearth, svalbard, verlegenhuken, take 4 - 'sailor's view' from north, 5 metres above sea level.jpg' (241 KB)
Download '2020-04-12 povearth, svalbard, verlegenhuken, take 5 - pedestrian view across verlegenhukflya coastal plain eastward, 1.' (22 KB)
Preview of image '2020-04-11 povearth, svalbard, verlegenhuken, take 1 - overhead view from 15 kms.jpg'
Preview of image '2020-04-12 povearth, svalbard, verlegenhuken, take 3 - view from north, 2 kms above ground.jpg'
Preview of image '2020-04-12 povearth, svalbard, verlegenhuken, take 4 - 'sailor's view' from north, 5 metres above sea level.jpg'
Preview of image '2020-04-12 povearth, svalbard, verlegenhuken, take 5 - pedestrian view across verlegenhukflya coastal plain eastward, 1.'
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Hi(gh)!
On 13.04.20 04:22, Bald Eagle wrote:
> =?UTF-8?Q?J=c3=b6rg_=22Yadgar=22_Bleimann?= <yaz### [at] gmx de> wrote:
>
>> The second tile in a series of more than 8000...
>
> Did you ever post the inc file for the pov-earth scene file that you posted?
No, because it would be impossible, as they typically are about 1.5 GB
large... even compressed with xz, there still weigh in at about 80 MB!
> Have you looked at
> https://grass.osgeo.org/download/
I just installed it... at least it seems to run, but before I'm able to
to do anything sensible with it, I'll have to work through the docs! Not
tonight...
> http://www.f-lohmueller.de/pov_tut/backgrnd/p_wat1.htm
> http://www.imagico.de/pov/water/index.php
> http://www.ignorancia.org/index.php/galleries/irtc-entries/water/
> http://www.ignorancia.org/index.php/galleries/old-images/sea-buoy/
> http://www.ignorancia.org/index.php/galleries/old-images/spanish-patio/
> http://www.ignorancia.org/index.php/galleries/archaic-images/marsh/
I'll try them... but first I have to re-calculate the mesh2 from
n80e017, as I missed adding a (provisional) texture before!
See you in Khyberspace!
Yadgar
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