I've tested to resave a default CFS3 dds dxt3 terrain texture with alpha channel using DXTbmp (Just open and save without any changes). I've used the dxt3 file format since DXTbmp shows that the default terrain texture was in that format. The "new" dds file looks OK in DXTbmp, exactly the same as the original texture and also the alpha channel looks identical.
When I check it in game it looks OK near the plane but further away the texture becomes very blurred.
The original texture looked OK without blurriness.
There are several settings in DXTbmp for mipmaps like "Use 16 bit dither", the drop downs with Box, Quadratic, Cubic, Catrom etc and also differnet scaling filters.
In the test I used the default settings:
I didn't check the '16bit dither' box.
Scaling filter selected 'none'.
I have no problem with blurriness if I save as dds dxt3 without mipmaps.
Which settings in DXTbmp should be used for best quality CFS3 textures with mipmaps and alpha channel?
Thanks very much in advance...
It seems to be a common problem with mipmaps (in FS as well).
I have a feeling that the nVidia library I use doesn`t give the same results as microsofts own imagetool. Resaved textures seem to switch mimaps differently from the original and switch in the smaller (more blurred) mipmaps too early
You could try experimenting with the different filter and scale settings but you may get the best results using imagetool. Or just do it without mipmaps
Remember that DXTBmp will discard the existing mipmaps when you load a texture and create a new set if you save
It will also create a new main image (even if you have made no changes) so avoid re-editing DXT3 too many times as DXT compression is lossy. Make a 32 bit copy right at the start and only work with that (saving out a seperate DXT copy when you want to put it in CFS)
Thanks for your quick reply and also thank you very much for all handy programs you have made for CFS!
I’ll try your suggestions!
Now I have spent quite some time converting to dds with these programs and testing in CFS3:
ImageTool CFS3 18.104.22.168
ImageTool FS2004 22.214.171.124
ImageTool FSX SP1 10.0.61355.0
ImageTool FSX SP2 10.0.61472.0
Paint Net 3.5.8
Paint Shop Pro 7.02 Nvidia plugin 3.02
It’s only ImageTool 126.96.36.199 that makes terrain mipmaps as good as the original CFS3 terrain tiles, at least on my computer and I have an ATI videocard. It doesn’t matter if it’s dxt1 or dxt3 with or without alpha mask.
In these pictures you can clearly se the difference:
Converted to dds with mipmaps using the Nvidia plugin.
Converted to dds with mipmaps using ImageTool 188.8.131.52.
I have a sneaking feeling that imagetool does something special with the mipmaps that is optimised for FS/CFS.
DXTBmp uses the nVidia DDS library to output textures. The Photoshop plugin uses the same libraries and I wouldn`t be surprised if the other programs also use code based on the nVidia library. I would expect all these methods to create very similar results
I remember using the commandline options in imagetool and there is a flag you can set to specify that the output is to be used for terrain. My guess is that it sets something in the file that tells FS/CFS to switch mipmaps at a greater distance than normal so making it look slightly sharper for longer. Its not that the image data is any better just that it holds on to the higher mipmaps for longer. In the same way that aircraft can be made to look sharper by removing the mipmaps (so forcing the use of the full image at all distances) delaying the switch to the next mipmap will extend the distance before terrain switches to a smaller (blurrier) mipmap.
On the other hand it is possible that the mipmap scaling algorithm used by imagetool is different to nVidia and creates mipmaps that are particularly optimised for terrain. The nVidia code is not FS-Specific as most games these days use DDS. There are options available in the plugin (and DXTBmp) to use different scaling algorithms and it may be worth experimenting with these to see if they make any difference in this situation.
Or just use imagetool (for the final output at least)
Yes, I noticed there was a terrain flag, but I didn’t use it in my tests.
It was also a surprise to me that it was only the CFS3 ImageTool that gave a sharp terrain look in CFS3. DDS tiles converted by later ImageTool versions looked similar to those converted by the Nvidia plug-in, when I tested in CFS3.
If I open the converted dds files and compare the mipmaps created by different programs/settings they all look the same.
So I guess you are right about there’s some special optimizing in ImageTool for the Microsoft CFS/SF titles.
Thanks for sharing your insight regarding this!
Very much appreciated!