I'm having problems with texturing on a 3DS model I'm trying to import into Celestia
I have a single 3DS file. A single object with multiple pieces of geometry.
I have three textures. Two hull textures (256x256) and a glass texture (128x128).
I export as a 3DS file from both Studio MAX and Milkshape and in both cases the model appears in Celestia with it's texture mapping all screwed up.
Although each piece of geometry appeared to have the correct texture applied, I guessed it might because I was using multiple textures so I remapped the model to use a single texture (512 wide x 256 tall) I re-exported and the textures were just as messed up.
Anyone got any ideas why this might be? I've seen other 3DS files on Celestia Motherload that use multiple textures and they appear to work okay.
Anyone got any ideas why this might be?
Regards
Crow
UVW problems
UVW problems
Scarecrow
Environment Artist
Blitz Games - Leamington
Environment Artist
Blitz Games - Leamington
You need to provide images showing the problem: what it looks like and what it should look like. A copy of the actual model may be necessary, too. Otherwise we can only make wild guesses.
One of Celestia's restrictions is that multiple textures can't be used on the same mesh. That is, a model can contain several different solids, but each of them can only have one texture applied to it. (In Anim8or, for example, one can merge several solids, each with a different material, into one solid. At that point only one of those materials will be applied to the final solid when it's drawn by Celestia, although it'll be applied to each of the sub-solids individually. That's usually not what you want to have happen.) If you want several different textures to be applied to different parts of an object, that object has to be cut into pieces. They can be made to look like a single object when Celestia draws them but still will be separate meshes within the 3D model.
Another problem is a bug/limitation in how Celestia handles translucent texture images -- those with alpha channels that specify opacity. They only work in specific simple cases. My understanding is that multiple display passes are necessary to draw them correctly, which would slow Celestia too much. In other words, translucency should be specified in the material definition in the model, not defined in a texture file. And even that doesn't always get drawn properly.
Do either of these cases describe what you're trying to do?
One of Celestia's restrictions is that multiple textures can't be used on the same mesh. That is, a model can contain several different solids, but each of them can only have one texture applied to it. (In Anim8or, for example, one can merge several solids, each with a different material, into one solid. At that point only one of those materials will be applied to the final solid when it's drawn by Celestia, although it'll be applied to each of the sub-solids individually. That's usually not what you want to have happen.) If you want several different textures to be applied to different parts of an object, that object has to be cut into pieces. They can be made to look like a single object when Celestia draws them but still will be separate meshes within the 3D model.
Another problem is a bug/limitation in how Celestia handles translucent texture images -- those with alpha channels that specify opacity. They only work in specific simple cases. My understanding is that multiple display passes are necessary to draw them correctly, which would slow Celestia too much. In other words, translucency should be specified in the material definition in the model, not defined in a texture file. And even that doesn't always get drawn properly.
Do either of these cases describe what you're trying to do?
Selden
Okay,
This is what the model looks like in Studio Max, Maya and even Milkshape.
One 3DS file with three seperate pieces of geometry. Each piece of geometry has a seperate material with one single BMP file texture applied to it. The two body textures are 256x256 and 16mil colours. The glass texture is 128x128 and 256 colours.
I realise the glass isn't transparent. I know it needs to be a TGA rather than a BMP file. I'll get to that once I get the UVWs working.
All this done, this is what the 3DS file looks like in Celestia:
Each piece appears to have the correct texture applied but the mapping itself is all screwed.
I've tried making it all one single piece of geometry and applying just one texture to the whole thing and still it comes out screwed.
I've reset the x-form in Studio MAX which bakes the mesh and removes all transforms.
I've frozen transform in Maya which does the same thing.
I've tried converting to CMOD but it made no difference.
I've run out of ideas now.
Any suggestions?
Crow
This is what the model looks like in Studio Max, Maya and even Milkshape.
One 3DS file with three seperate pieces of geometry. Each piece of geometry has a seperate material with one single BMP file texture applied to it. The two body textures are 256x256 and 16mil colours. The glass texture is 128x128 and 256 colours.
I realise the glass isn't transparent. I know it needs to be a TGA rather than a BMP file. I'll get to that once I get the UVWs working.
All this done, this is what the 3DS file looks like in Celestia:
Each piece appears to have the correct texture applied but the mapping itself is all screwed.
I've tried making it all one single piece of geometry and applying just one texture to the whole thing and still it comes out screwed.
I've reset the x-form in Studio MAX which bakes the mesh and removes all transforms.
I've frozen transform in Maya which does the same thing.
I've tried converting to CMOD but it made no difference.
I've run out of ideas now.
Any suggestions?
Crow
Scarecrow
Environment Artist
Blitz Games - Leamington
Environment Artist
Blitz Games - Leamington
Well, here's the test that I'd try: get the freeware program Anim8or. It's the program that many 3D novices (like me) use to create models for Celestia.
What does the 3DS model look like when you import it into Anim8or as an Object?
If it looks OK, then export the Object to a new 3DS model file. What does that one look like in Celestia?
(Anim8or sits for a while so you can admire its logo before it displays its Object and other menus. Be patient. It looks for the BMP textures in the same folder with the 3DS model.)
What does the 3DS model look like when you import it into Anim8or as an Object?
If it looks OK, then export the Object to a new 3DS model file. What does that one look like in Celestia?
(Anim8or sits for a while so you can admire its logo before it displays its Object and other menus. Be patient. It looks for the BMP textures in the same folder with the 3DS model.)
Selden
Jestr,
No. That's one of the first things I thought of. It's a problem I always had with Dark Basic. They are definately seperate materials. I've got a feeling it is a material issue though. I'll keep plugging at it. Once I get intot he office on Monday morning, I'll try what Selden suggested and import the 3DS into Anim8or. See what happens then =)
Crow
No. That's one of the first things I thought of. It's a problem I always had with Dark Basic. They are definately seperate materials. I've got a feeling it is a material issue though. I'll keep plugging at it. Once I get intot he office on Monday morning, I'll try what Selden suggested and import the 3DS into Anim8or. See what happens then =)
Crow
Scarecrow
Environment Artist
Blitz Games - Leamington
Environment Artist
Blitz Games - Leamington
Okay, I've tried importing the 3DS file into Anim8or and the model looked absolutely fine. I re-exported it and it still looks screwed in Celestia!
As an aside, Anim8or refused to open the glass file (it being 256 colours), so I changed the glass texture to RGB and it loaded fine in Anim8or.
Sadly, the model still looks screwed in Celestia =(
Jestr, I'll mail you the model and textures, as you suggested in your PM.
Much appreciated.
Crow
As an aside, Anim8or refused to open the glass file (it being 256 colours), so I changed the glass texture to RGB and it loaded fine in Anim8or.
Sadly, the model still looks screwed in Celestia =(
Jestr, I'll mail you the model and textures, as you suggested in your PM.
Much appreciated.
Crow
Scarecrow
Environment Artist
Blitz Games - Leamington
Environment Artist
Blitz Games - Leamington
Problem Solved!
Jestr had a look at it for me and discovered that if you use JPG or PNG instead of BMP it works fine.
No idea why this is, but it makes sense to use JPGs instead because they are much smaller than BMPs.
Thanks both for all your time and help.
Now then, to get modelling the real stuff I want to put in Celestia...
Crow
Jestr had a look at it for me and discovered that if you use JPG or PNG instead of BMP it works fine.
No idea why this is, but it makes sense to use JPGs instead because they are much smaller than BMPs.
Thanks both for all your time and help.
Now then, to get modelling the real stuff I want to put in Celestia...
Crow
Scarecrow
Environment Artist
Blitz Games - Leamington
Environment Artist
Blitz Games - Leamington