Textures applied to models are reversed

[Reiko]

I noticed all of the textures applied to models come out in reverse in celestia. They look like mirror images of themselves.

Here is the texture how it is.




And here is how it looks in celestia




Anybody know how I can fix this? Simple mirroring the textures in photoshop doesn't work because they end coming out unaligned when loaded in celestia.

[zhar2]

Well simply reversing the texture wont work becouse those are uv maps, my only advice is to retrace your steps when you made that uv texture and fix the problem there (take this a a test, and re-make the uv-map).

[selden]

Reiko,

What 3D design program or UV mapping program are you using?
Or did you get the model and its textures from someone else?

I've had quite good luck using Anim8or under Windows. It isn't as sophisticated as Blender, but is easier for me to use. If it looks OK in Anim8or, it should look OK in Celestia.
http://www.anim8or.com/

[cartrite]

I think I remember seeing something like this long ago when I just started using Blender. It happened when the normals were reversed and the surface was semi / transparent. Sometimes this can be fixed with cmodfix by recalculating the normals. This may or may not be the problem here?

What model are you using? Did you create or modify it yourself. I didn't see anything like it at the Celestia Motherlode.

cartrite

[Reiko]

This model and textures I'm importing from a game and didn't make myself. I have to run the model through two different 3D modeling programs to get it into cmod format for celestia. Is it the textures I need to fix or something in the model?

[cartrite]

Without seeing the model or it's textures, I can't answer that. If you are using modeling programs though, maybe you should use Anim8or like Selden suggested.

If it looks OK in Anim8or, it should look OK in Celestia.

cartrite

[Reiko]

I am using anim8tor, I'm using two programs in fact. The model comes in .nif format so I have to import it into milkshape3D to convert it to .3ds. Then I use anim8tor to convert the .3ds model into .cmod format. I would love to do it all with just anim8tor but it doesn't support .nif format.
Perhaps through one of the conversions something is changed that causes the problem. I guess I'll just have to do some careful photoshopping on the letters to make them come out straight.
If anybody has the time to look at it, I would be more than happy to send the model and textures.

[cartrite]

If you have the 3ds model and compress it to a zip file, you may be able to post it here if it is small enough. Also put the textures in a separate folder and compress that to a zip file. Just upload them as you would an image. I have uploaded zip fies here but I'm unsure what the size limit is. You can also send it to my email. If that doesn't work, send me a PM and I'll send you my email address.
cartrite

[Reiko]

I found this via google.

Celestia currently handles textures applied to 3ds mesh objects in an unusual way - instead of wrapping around the surface of the mesh, the texture appears to pass through the centre of the mesh object and be pasted onto the inside of the opposite surface. The resulting east-west mirroring effect can be offset by keeping the applied texture 180 degrees out of alignment with the orientation of the mesh object, but the north-south mirroring must be compensated for by pre-mirroring the applied texture, so that it appears the right way up within Celestia.

This effect occurs in all the 3ds objects in Celestia: Phobos, Deimos, Amalthea, Proteus, Hyperion and various asteroids and comet nuclei. All require their applied textures to be mirrored north-south for a correct Celestia appearance.

http://www.lns.cornell.edu/~seb/celesti ... x-125.html

But that is for an older version of Celestia. Could the same thing be happening here? Mirroring and rotating the texture just knocks it out of alignment.

[cartrite]

I opened the file you sent with both Blender and Anim8or. They both show a mirror image. So you must have mirrored it somehow when you created the 3ds file from the original .nif format.

yama2.jpg

Try to create the 3ds file again and see if there is a setting in milkshape3D that will mirror each group. I've never used that program, so I can't help out there.

cartrite

[cartrite]

I was trying to import the file into Blender 2.45 and I couldn't work with it. Only view it or export it. The same was for Anim8or. But I just imported it into Blender 2.40 and I'm able to work with this because the groups have been separated. I'll let you know if I have any luck mirroring the model.
cartrite

[Reiko]

Cartrite I love you!! I just do a left-right mirror of the model in milkshape and the textures come out perfect!
Thank you so much for taking the time and looking into this. I really appreciate it.

[cartrite]

I'm glad this all worked out for you because I wasn't able to import the UV coordinates into Blender. Only the model. So I wouldn't have been able to export a working model. The UV map is looked pretty complex too. Parts of the model seem to only use parts of the textures. So it would have been very difficult to remap them. At least for me it would have.
cartrite

[cartrite]

I played around with the model that Reiko is using and finally figured out how to import a working model into Blender with the original UV texture coordinates. This allowed me to "fix" problem with the mirror images Reiko was having.

First I had to import the 3ds file into Anim8or and export the model in waveobject (.obj) format.

When I imported the 3ds file into Blender, the UV texture coordinates were there but I couldn't work with the model. It was only available in OBJECT Mode. When I imported the obj file into Blender, I was able to access Edit Mode and UV Texture Mode but the UV coordinates were not imported. I am able to remap the UV coordinates but they were different from the textures that came with the model. So extensive work would have been needed to use the model.

The solution was actually simple. I imported the 3ds file. Then I imported the obj file into the same model. After I joined the objects, I was able to delete the 3ds model and still have the UV coordinates in the obj file.They were separated into 5 meshes though. So I corrected each mesh and saved it as a blend file. After all the fixes were done, I was able to start Blender as blank and append and link each mesh to put them together. This model only had Object Mode available but I was able to export it in 3ds format and then use 3dstocmod. The only thing I had to do was change the file names back to the original names. There was some truncating and the file names in the 3ds file were not complete.

The model worked in Celestia though.

yama.jpg

cartrite

[Reiko]

For those wanting to import models for Celestia I recommend using milkshape 3d if you can get it. Import your model into milkshape and hit select all. Then click on vetex and select mirror left <--> right and problem solved.
One drawback to milkshape is it will sometimes shorten the texture coordinate names so you'll have to go back in and change them or change the name of your textures.

Thank you again cartrite. I would have never thought to mirror the object.