Scenery Texture files

[WarHorse47]

Got a question for you scenery experts. :mixedsmi:

In looking at some of my addon scenery, I noticed that there are a lot of *.bmp files that are greater than 1024 Kb - about 244 to be exact. They range from 1366 Kb to 5462 Kb which implies that some of these are not DXT3.

Since my video card runs best with DXT3 format with no mips and I'm always looking to decrease the loading time of my addon scenery and reduce my FS9 footprint, I was wondering if it would be any harm in converting these files to a 1024 Kb DXT3 format?

Anyone try this and have any advice??

:ernae:
Thanks


--WH

[Tom Clayton]

The best advice anyone could give would be to make a backup copy of the entire texture folder before trying it.

[aeromed202]

Can't say for sure but I'm fairly certain that I tried this before, and for the same reason. What happened was that when I started out in that region, or flew into it, the game would do one big stutter then all ground terrrain textures would flip to solid color scapes like the old FS4. Sometimes after several minutes the textures might agonizingly crawl back but mostly I would have to morph hundreds of miles anywhere else to get back to normal. Nothing but a full reinstall finally fixed it. I figure I just missed one or two texture files when I tried to put things back to pre-fiddle conditions. I just can't be sure if changing the files made all that happen.
Having done that, I tried other more controlled and much smaller tests like clouds (before HDE came out) with some better results. I still plan to try other small areas using the DXT to BMP converter. Currently I'm having some successes with that flattening tool to fix some issues with UT.

[Dangerousdave26]

1024 does not refer to KB but to Pixels

Specifically 1024 pixels by 1024 pixels square.

You can have images in any .bmp format that are 256, 512, and 1024 pixels square.

The size of the image will vary depending on the image on the bit map as well as the type of .bmp.

[Dangerousdave26]

Here is an example. This is a modified Cessna 172 bmp. The original was DXT3 and was 1361.92 KB (1.33 MB) and 1024 by 1024 pixels squared (1024 for short).

This one is still 1024 by 1024 pixels but is in 32bit format so its size is now is 4096 KB or 4 MB

When I changed this image to a DXT1 file the image size drops to 512 KB but the size is still 1024.

I would not do anything to your scenery files until you positively identify their format and size.

[WarHorse47]

Thanks for all the responses. This has always been a complicated issue for me to understand.

What I know so far is that the textures for my addon scenery are mostly at 1024 X 1024 16 bit textures or smaller. There are a few at 32 bit.

Other than the file size, I don't know of any other way to determine the pixel size of an image file unless I examine each individually with DXTBmp. My older video card seems to run quite well with 1024 X 1024 16 bit textures with no mips, so this is why I was inquiring about converting some of the scenery texture files to see if it would improve loading of scenery. This works with aircraft textures so why not scenery textures.

Thanks
:ernae:

--WH

[pfflyers]

One thing I've noticed with scenery bitmaps and mips is that trying to remove mips to improve image quality actually caused my computer to work harder to load the scenery.

When the texture was set to begin loading from a great distance (set by LODs ?) it would try to load the max resolution right away, this made the scenery look wierd and/or CTD.

My experience has lead me to not mess with other people's scenery as they know more about it than I do.

[Dangerousdave26]

pfflyers

I have to agree I have never quite understood how Mips could slow a system down but it must for some because its well publicized.


WarHorse47

Here is a down and dirty way to tell what size the image is in Pixels. When you put your pointer over the icon for the file it should (depending on system settings I am sure) show you details about the file.

In this case it shows us that c172_d.bmp is
Dimensions: 1024 x 1024
Type: Bitmap Image
Size: 682 KB

You can see it also shows those details in the left details pane

What it can not show you is the file type but we can guess that by how the file is presented to us in the folder with thumbnails turned on.

8bit, 16 bit(all formats), 24bit, and 32 bit textures will all be visible as an image.

DXT1, DXT3, DXT5, are shown as the icon that opens the image. This is of course because the windows operating system does not understand the image format.

After that you must move to using more detailed programs like DXTBMP by Martin Wright and ImageTool by the Aces Team. Both of these products will show you the details of the image.

BTW I was a little misleading earlier when I said


You can have images in any .bmp format that are 256, 512, and 1024 pixels square.

Those are the common sizes that you and I deal with but Flight Simulator 9 and X both really can only use textures that are sized around the power of 2

What that means starting from the highest (right now) to the lowest

2048 <--- FSX only
1024
512
256
128
64
32
16
8
4
2

Where would you see the smaller sizes 16 and below? I don't have a clue my guess is they are no longer used. There are lots of 16 - 512 in the texture folder in the root FS9 folder though.

[Tom Clayton]

Windows can't preview any bitmap compressed by DXT, so that's why you get the "Drawing failed" message. If you have the DXTbmp app installed, look in the root folder for a rich text file called "Texture Formats used by FS2002." It contains a great explanation of what's going on with all of the different formats. (There's also one for FS2004, but it just states that the formats are unchanged from FS2002 and you should read that document.)