hi martin,

while working on a scenery project for fs2004, i downloaded the nvidia dds photoshop plugin, as it allows to save directly into dds file format while choosing any dxt compression method. i found that this plugin produces much less degradation/artifacts when using dxt3 compression than microsoft's imagetool and dxtbmp (sorry). so, i figured i could load that dds file using dxtbmp and save to extended bmp format also in dxt3. but, dxtbmp will compress the file again so it degrades the image, even though the dds file was already compressed into dxt3 in the files place. is there any way to convert dds dxt3 directly to fs9 extended bmp dxt3 format without "double-compression"? thanks very much in advance...

Firstly - unless they have improved the code since I last updated it the plugin should give pretty much the the same results as DXTBmp as I use the nVidia code library for my conversions. However I have been unable to update for a long while now as they have messed around with the library interface and made it very difficult for me to use the newer code.

When I first started looking into DDS I wrote a simple converter that would take a DDS file and convert it to Extended BMP just by replacing the header. This results in a BMP file with the unchanged DDS image data. This would answer your situation and is still available on my Beta page (DDStoBMP)

One caveat - DDS and BMP have the image data stored the other way up from each other so to preserve the orientation you will need to "flip" the image before exporting through the plugin. This will result in an upside-down DDS file but when you pass it through DDStoBMP the final BMP file will be the right way up again.

hi martin,

thank you for the quick reply, i appreciate it. from my own testing i found that the latest nvidia plugin produced much less artifacts on compression for nightmaps, where there is a high level of contrast and "gradients" as colors transition from light to dark in certain areas of the texture. for daymaps, the plugin and dxtbmp still produce very similar results.

in any case, thank you for pointing out your ddstobmp converter; i tried it out and it works great. i apologize for not noticing it on your program list before posting this query! thanks again for making such valuable tools for the fs design community.