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Demand for an additional grafic file format

Posted: 08.03.2003, 20:28
by jim
Hi all,

I would it agree if Celestia can handle 8 bit palleted DDS files. This format can be build with all dds converters (NVtools, Photoshop plugin, ...). It has the same size (in the memory) as the DXT3 or DXT5 format and supports also mip maps.

Now the reason why i want this format.
I build in the last weeks many normal map (i think over 20) and i'd tested several file types. Within an other post i'd reported about ugly boxes with normal maps in DXT1c format. The effect can be reduced by the DXT3 or DXT5 format but not complet. Now i tried the PNG and JPG format. PNG works fine but now the surprise a normal compressed JPG produces artifacts that i can't belief it. After further tests i came to the result that only high quality JPG's with low compression work satisfactory. The main result is that normal map are very sensitive to comressed grafic formats.

JPG and PND format looks nice but they have one big disadvantage they becomes very large in the memory. A 4K map get a size of 43 Mb (32bit + mip maps). I searched for an other solution and read obout the 8 bit palleted DDS format. To simulat this format i'd tested an 8bit PNG. The color reduction causes no visble disadvantge. This 256 color normal map works perfect.

I hoppe this is reason enought to implement that grafic format. Finally i think this format is not only usefull for normal maps.
Chris please give me an answer how do you think about.

Bye Jens