Exporting a Blender model with textures to the 3ds format ?

[John Van Vliet]

John,

could you be more specific ? When I try to open the obj file with cmodview, it doesn't load (I get an error message).

https://github.com/nasa/NASA-3D-Resources/tree/master/3D Models/Curiosity (Dirty
download the blend AND textures

open the blend file ( in blender)


remove the 4 hidden cubes under the rover

then export as a obj
then is cmodview
( FLIP!!! the images upside down top to bottom !!!)
and assign the images to the uv mapped mesh

[Cham]

Blender is so clumsy and ackward to use. I'm unable to select and remove the four pieces you're talking about.

cmodview refuses to load the .obj file.

[john71]

Selden: All right, my bad, thanks for the links!

[John Van Vliet]

you might have to reimport the obj file then remove the cubes
then re export it

[Goofy]

Following Selden's request, I tried to write a simple ssc for the Curiosity model uploaded here, in order to have it flat on Mars surface.
Here the result.
Please note that in first image 2 left wheels look like covered by sand: it's not a searched feature, I found and left it, remembering what happened to Spirit Rover on 2009.

Look at the wheels partially covered by sand

Nice, do you agree?

This is the ssc:

Code: Select all

"MSL_Curiosity" "Sol/Mars"
{
   Class         "spacecraft"
   Mesh "MSL_Clean.cmod"
   Radius      1
  LongLat       [137.44 -04.59 0.55]  # Curiosity landing place in galle crater
   Orientation      [100 1 0 0] 
   Albedo      0.50
}

Just now I'm working on textures too, hope to obtain some good results.
Here a very preliminary example:

Click on images to see them in full resolution.
Bye soon
Goofy

[Cham]

This is the clean version. The dirty version is nicer.

About the SSC, I already have the one corresponding to the exact point of landing :

Code: Select all

SurfaceObject "Curiosity:Mars Science Laboratory" "Sol/Mars"
{
   Class "spacecraft"
   Mesh "Curiosity.cmod"
   Beginning "2012 08 06 5:17:57.3"
   Radius 0.0015 # about 3 meters long
   FixedPosition { Planetographic [ 137.4417 -4.5895 0.002] }
   FixedAttitude { }
   #Orientation [ 90 1 0 0 ]
   Albedo 0.1

   InfoURL "http://en.wikipedia.org/wiki/Curiosity_rover"
}


[Goofy]

Thank you Cham, it's perfect.
So waiting for your cmod model....
Bye soon.
Goofy

[Cham]

Take note that my actual dirty version has missing holes on its wheels. I'm currently unable to convert the right wheels.

The version without the holes is already pretty satisfying, but I'll try another way during the following days.

[Chuft-Captain]

I'm seeing depth-sorting issues with the "dirty" CMOD ... which suggests to me that maybe there is some transparency in the model. Anyone else seeing this?

[selden]

Are you using the original PNG surface texture images? I think they have Alpha channels which confuse Celestia. Try converting them to jpeg images to eliminate the Alpha (transparency) channels. Celestia has always had problems depth sorting transparent surfaces that are part of the same object.

[Goofy]

Yes, the same for me.
See images.
Bye
Goofy

[selden]

Yup. It's the PNG images.
You need to convert them either to JPG images or to PNG images with no transparency.

With original PNG surface texture images:

With PNG surface texture images with no transparency:

[Chuft-Captain]

Cheers Selden,

I hadn't noticed that the CMOD still refers to textures using the wildcard ( ".*") ... which means if you don't remove the original PNG's from the textures folder, it uses them in preference to the newly created .JPG's.
Easy fix is to just get rid of the PNG's which allows the CMOD to find the JPG's instead.
An alternative would be to hardcode the texture references in the CMOD to refer to the JPG's only.

CC

[Cham]

Okay ! With the help of a specialist on another forum, I succesfully imported the whole model with all its textures in my favorite modeler.

Expect a final model in the following days !

Added after 7 minutes 42 seconds:
I'm working on the model. There are lots of special pieces that aren't usefull for Celestia that need to be erased. This is why the model was so big (for what it is).

[Goofy]

With all pngs converted to jpgs it's OK.

But with a little glitch in all the 6 wheels, thet moreover show only normal, not dirty texture, I think....

Well done, anyway.
Thanks a lot.
Goofy

[Cham]

Here's a preview of the work in progress. The model shown here isn't final, of course. Just a test. But I know that the final work will come later today or tomorrow !

[Goofy]

Wow, the holed wheels!
You won!
Cannot wait to try it:
Bye soon

Goofy

[Cham]

I now have one version ready for release :

Before releasing it, I want to do another try at using full PNG textures (without transparency), since JPGs degrade the quality of the textures (even with the lowest compression level). JPG sucks !