(3DS) A texture that displays on the model but can't be found in the texture list

[Fawfulthegreat64]

I'm going through a dump of the Japanese release of Mario & Luigi RPG 3 DX and came across this oddity with the Midbus battle map (in Fawful Theater).

The main texture for the majority of the stage (including the floor and the large Fawful emblem in the center) is missing from the texture list, can't be found on its own, and yet is clearly displayed on the "model" in the viewer. I need to find a way to extract that texture. To see what I'm talking about, see below: You can see it in the viewer, but below the texture list is a screenshot of the File Explorer with all the extractable textures, it's not included with them. If anyone's familiar with a similar issue viewing 3DS models in SPICA (or Ohana3DS, as the texture list I get with that program also doesn't include it) is there any way to get that texture?

[CHEMI6DER]

The main texture for the majority of the stage (including the floor and the large Fawful emblem in the center) is missing from the texture list, can't be found on its own, and yet is clearly displayed on the "model" in the viewer. I need to find a way to extract that texture. To see what I'm talking about, see below: You can see it in the viewer, but below the texture list is a screenshot of the File Explorer with all the extractable textures, it's not included with them. If anyone's familiar with a similar issue viewing 3DS models in SPICA (or Ohana3DS, as the texture list I get with that program also doesn't include it) is there any way to get that texture?

Hi. I'm also currently poking around the files of this game. It's very strange that it doesn't show up at all. I've checked both original Ohana, Ohana-Rebirth and SPICA and they all don't list the texture at all. Even Kukkii doesn't list it...Thought Ohana's Texture Info readout is interesting...maybe it's embedded in a shader?

And also regarding one of your other threads: PTX is probably a container of some sort because one of the ptx files I inspected under a hex editor had not only a BCH but also a BTI file inside of it. For many cases just stripping away everything before BCH magic will just work fine to extract the bch.
Also, do you know how _CA_INFO_ entries are structured? I found out that the first 16 bytes(maybe first 12 bytes, IDK as I haven't researched more yet) list texture filenames in C-style null terminated string format. And then there's data which probably contains stuff like texture encoding, dimensions, tile size and all other texture related stuff. I didn't manage to understand it, but I was able to get something resembling a properly decoded texture by manually playing around with Kukkii's RAW Import menu. 
On the two images below you can roughly make out that it's Midbus.


BTW, how did you extract bg4 archives? The problem is that no tools whatsoever want to open the extracted BCH files and I think it's because of the compression. I tried using MSBT Editor Reloaded but it extracts only compressed files and doesn't have a decompression routine, neither does it's source mention which compression it uses.
Edit: found that one QuickBMS script that extracts bg4 properly. Turns out the compression is BLZ. Gonna put a link to it here in case someone searching for this needs it: link

[CHEMI6DER]

OK, so I've poked around the decoded H3D stuff from SPICA using VisualStudio's debugger and I still have no idea where that texture could be. I've looked through all texture, material and model info and couldn't find anything interesting. But I can definitely disprove my awful assumption(because I don't know how shaders work) about it being embedded in a shader: this file has 0 shaders(if we believe SPICA that is). I don't feel like playing the guessing game anymore so I'm gonna try filing an issue on SPICA's GitHub page about this oddity.
Sometimes obvious really is obvious, isn't it? So I messed up the main texture(bmp_o_kpa_01_01) by manually loading it into Kukkii as a RAW file and selecting all correct settings except for texture encoding...and if texture encoding is set to L8(and some other, but L8 just has the clearest picture) we can see that the full image is present in that file!

Now why could that be? From what I've seen with other maps from this game it seems that some protruding objects(such as pillars) use cutouts of the main texture with additional transparency applied. In this case, it seems, the alpha channel is always present in the file and is simply ignored when that texture is applied to a specific mesh. If I export this texture to png and then use GIMP(PhotoShop doesn't work for this, I tried) to decompose the colour channels to RGB(just simply throwing out alpha) and then compose them back and we get a proper image! It takes some time to do this, but I'm sure I can make a quick mod to SPICA/Kukkii to have a checkbox to ignore the alpha channel on a specific texture. Btw, here's the properly decoded texture:

[Ploaj]

I've got the sprite animations already ripped and ready. (Complete with parts this time around  ) 
Just gotta wait for the game to release in more regions.

[Fawfulthegreat64]

Interesting, as I tried removing the alpha channel in Photoshop and I just got a black background. But to be fair, a lot of that file encoding stuff is Spanish to me

Also @Ploaj, awesome work! I was a tad worried this one wouldn't get ripped as fast due to the waning interest in the 3DS (and sprites are the one major thing I can't do, at all lol)

must... resist... urge... to... ask for some samples of Fawful... crap i failed

[CHEMI6DER]

Interesting, as I tried removing the alpha channel in Photoshop and I just got a black background. But to be fair, a lot of that file encoding stuff is Spanish to me

As I've stated in my previous post, Photoshop doesn't work for that. I tried myself to no avail. Just download and use GIMP(it's free).
Just open the .png you've exported from SPICA/Ohana/whatever in GIMP -> *In the menubar* Colors -> Components -> Decompose... -> *In the popup menu* set "Color model" to "RGB", Enable "Decompose to layers", disable "Foreground as registration color" and click "OK" -> *now you should see a grayscale image in the editor* -> *In the menubar again* Colors -> Components -> Compose... -> *In another popup menu* set "Color model" to "RGB" *everything else should automatically be set to proper values* and click "OK" -> *You should see a proper color image in the editor* -> File -> Export As *because you have to use Export to save as anything except GIMP's own format*-> *export it to .png wherever you want to* -> Profit!

I've got the sprite animations already ripped and ready. (Complete with parts this time around  ) 
Just gotta wait for the game to release in more regions.

Great work! Good to know that there still people who are also interested in ripping these games!