jim wrote:Hi all,
Now since a 16 bit elevation map for mars is available I played a little bit with the 5760x2880 data set and build a 8k normal. This is the result: (8k DXT1 Mars map + 8k DXT3 normal map + 4k clouds)
Ok I'm enthusiastic about the 16 bit format. That's what we need to create 8k or 16k normal maps. But the problems comes with the software which can handle this 16 bit format. Photoshop 6 can open this file format but supports only some basic function nothing that's usefull to create a normalmap. Next try was Gimp 1.2.4 for windows this highly praised software by some people of this forum. After some futile tries i search the web for more infos and found out that the standard version of Gimp supports no 16 bit per channel formats. The idea installing the needed plugin(s) was fast stop by reading the way to do this for a windows environment. Since I know that Gimp needs up to 4 time more memory for a picture than other photo editors I'm not good to speak about this software ( Ok it's better than MS Pain ). My last try was Corel Photo Paint 10 and i found what i need. Most filters are also disabled with the 16 bit files but the user defined filter works. With this filter it's possible to produce the red and green channel for a normal map. After some final work in Photo Shop and the resizing with Irfanview I get my new 8k normal map.
This is only a preview because i'm working on a new Mars this time not based one a Space Grafics texture.
The next project is a 8k color Moon (without stripes).
Bye Jens
I now have made a /phantastic/ 16k, ~16bit (dithered) normal map from the /final/ MOLA elevation data. Even the 8k, ~16bit are much better than what we had before!(Note unless Jens' 8k map, the one I made is from resizing the 16k bump map and thus is genuine 8k resolution). Much less artifacts and as I always emphasized, the 16bit grayscale dephts is precisely what was always needed!
I guess by tomorrow I can show first 16k results here.
Doing the 16k normal map is sort of tricky;-). The MOLA data are 4x132MB, i.e. quite a bit to handle...
I use some gimp-perl plugins that I wrote to merge the 4 maps together seemlessly...
Jens, I really do not understand what you are saying: the people who wrote Gimp are not STUPID! Are you really believing that they just vast a factor 4 more memory for NOTHING? Of course, this depends on the number of UNDO steps that you chose etc.
The NVIDIA photoshop normalmap plugin does indeed only work on 8bit RGB images. However, the Linux GIMP normal map plugin works fine in 16bit, but see below...
Bye Fridger