since some time I am working on a challenging project of
producing a high-quality, fitting set of textures for
Earth, all 64k native resolution!
The base texture is of course the 84k- > 64k BMNG (Blue
Marble Next Generation).
Hardest do do was certainly the 64K NormalMap in
highest noiseless quality. It is essentially finished now,
in form of 2k x 2k VT tiles, with resolution optimized in
polar latitudes. The great point is that the normal map data
are precisely those that Reto Stoeckli (NASA) used to
(statically) shade the BMNG base texture! This elevation file
is a 84k, 16bit signed integer raw grayscale file. It's a 8
GB monster!
Reto Stoeckli, with whom I am in extensive communication,
blended the following 'latest generation' elevation data
together:
1. 3 arc-second = 90 m resolution SRTM dataset
(Shuttle Radar Topography Mission, [JPL, 2005]) from
60S-60N.
The SRTM instrument consisted of the Spaceborne Imaging
Radar-C (SIR-C) hardware set modified with a Space
Station-derived mast and additional antennae to form an
interferometer with a 60 meter long baseline.
2. 30 arc-second GTOPO30 dataset [USGS, 1996],
from 60N-90N, and to fill small voids in the SRTM
dataset, using bi-cubic interpolation.
3. RAMP II dataset (Radarsat Antarctic Mapping
Project Digital Elevation Model Version 2, [Liu et al., 2001])
from 90S-60S
+++++++++++++++++
At a later stage I shall provide an extensive tutorial
elsewhere
![Wink ;-)](./images/smilies/icon_wink.gif)
do all this yourself...
+++++++++++++++++
For now just a little flavor from my normal map tiles: I just
run Celestia with the normal map and the spec map. NO
base texture, to make the effect of the normal map clearly
visible! Below is a corresponding shot:
Bye Fridger
![Image](http://www.shatters.net/~t00fri/images/nm64k-test-earth1.jpg)
Next, I have inverted (for 3d visibility) a little piece from the
64k NormalMap!:
![Image](http://www.shatters.net/~t00fri/images/nm64-tex.jpg)