Saving texture files as 'DXT3' or 'Extended 32 bit 888-8'

[Jim77]

I see in my aircraft texture folders that some files are visible (I can see the fuselage, wings or whatever), and some it only has the generic MS Photos icon, not the 'picture' of what the file is. The MS Photo icon files are all saved as DXT3. The ones I can see are Extended 32 bit 888-8. The properties 'Item Type' of both are BMP files.

 

For the MS Photos icon only files, I see what the file 'picture' is when I open it with DXTBmp. Each file is named of course, but without opening with DXTBmp I cannot see exactly what the file contains. If I open the icon only file with DXTBmp then my paint.net editor, make changes to the file (change N#, add stripes), and change the 'Save as Type' from DXT3 to Extended 32 bit 888-8, then the icon only file is now visible. It is also a lot larger file, about 1 MB to now 4 MB. Saving as Extended bit 32 seems to make the aircraft image sharper when flying.

 

Is there a best way to save, DXT3 or Extended 32 Bit 888-8? Sacrificing hard drive space for a sharper aircraft? Hope I explained this clearly enough. I'm using FS2004. Thanks in advance.

[douga66]

The very simplified answer is use DXT3 (or DXT1 with alpha for lightmaps) for performance as this is the recommended format in the sdk. The 32 bit version when saved with DXTBmp or Imagetool is a larger version with much less compression which in turn displays a better quality images. On older systems the performance would take a hit from this as well as uses extra HD space. Newer computers should not have a problem with this however. Still the hard drive space can be used up much quicker with these larger files especially for flyable aircraft.

[tgibson_new]

My rule of thumb is to use 888 for flyable aircraft when it does indeed lead to sharper display. For AI and other situations I use DXT.

[defaid]

Hi.

 

I use 888-8 for all player and AI aircraft, but then my SSD is about the size of the warehouse at the end of Raiders of the Lost Ark. I'm not zealous about it - any new downloads or creations are converted to 888-8 but I have many that are untouched. If I don't intend to edit, then DXT3 is fine.

 

As Tom has pointed out, the drawback with 888-8 is file size.

 

The main drawback with DXTx is that the compression is lossy, which is to say every time you save & exit, the image is dithered and detail is lost. The dithering is cumulative and over the course of several edits you end up with rather sh**ty textures.

 

32-bit (or 888-8) is an uncompressed format so save & exit has no detrimental effect on the crispness. Also, saving in that format automatically adds an alpha channel if none previously existed (the -8 part).

 

I've not yet had need to edit any other textures (terrain, scenery et c.) so they are still in their original DXT1 or DXT3 formats.

 

If you have the storage, choose 888-8 but keep a copy of the original - I did once convert a bunch of addon airport textures (LICJ) and found that for some reason overhead streetlights on the apron got messed up.

 

D

[johnhinson]

For the MS Photos icon only files, I see what the file 'picture' is when I open it with DXTBmp. Each file is named of course, but without opening with DXTBmp I cannot see exactly what the file contains. If I open the icon only file with DXTBmp then my paint.net editor, make changes to the file (change N#, add stripes), and change the 'Save as Type' from DXT3 to Extended 32 bit 888-8, then the icon only file is now visible. It is also a lot larger file, about 1 MB to now 4 MB. Saving as Extended bit 32 seems to make the aircraft image sharper when flying.

A properly formatted DXT3 file does not contain a preview image - it is a simple as that!

 

John

[Jim77]

Thank you all for the replies.

[defaid]

As Tom has pointed out, the drawback with 888-8 is file size.

 

Reading back, I think I should apologise to both Jim and Tom...

[tgibson_new]

Hi,

 

No problem, I don't have an issue. :)