Modelling for Celestia

[selden]

I've written yet another Web page


Modelling for Celestia
describes some of the things I've learned while creating models for Addons. It also includes a few links to Topics here in the Forum where modelling has been discussed.

Please let me know of any improvements, additions or deletions that should be made.

[Boux]

I've written yet another Web page


Modelling for Celestia
describes some of the things I've learned while creating models for Addons. It also includes a few links to Topics here in the Forum where modelling has been discussed.

Please let me know of any improvements, additions or deletions that should be made.

Thanks for this, Selden, very informational and useful indeed
Regarding your export script for Anim8or, it would be very nice if it were able to output directly the complete *.cmod file, ready to process/fix.
In dos-like console command, it would be something similar to this:

Code: Select all

copy /B myfile.cmod.cmod_material+ /B myfile.cmod.cmod_mesh /B myfile.cmod


Perhaps the scripting language you are using can do something similar.

[selden]

Boux,

Thanks for the kind words.

Unfortunately, Anim8or's scripting language does not allow direct communication with the operating system, so the script can't issue a copy command. It doesn't yet support reading from a file, either. If and when either one of those features is available I plan to have the export script produce a single file.

[Boux]

Ah, OK, I see...
By the way, I have made a correction to the command line for Windows users.
The /B switches are needed to specify binary files.
Otherwise, the command will add a ctrl-z at the end of the new file, which will break the file.

[selden]

Boux,

Thanks for the command example!
I've now included a slightly different version in the Web page.

[Boux]

I see...
Actually, for very big models, it is faster to merge the two files through the console than opening both files in two instances of an editor, copy/paste the material on top the meshes and save as a new file.

[ElChristou]

Nice initiative Selden! Tx!
I'll try more merging on my next models

[selden]

ElChristou,

Good luck with the merges!

Just don't merge meshes that use different materials. That won't work with 3DS models exported for use with Celestia. All but one of the materials will be ignored.

I'm beginning to wonder if mesh merging is what has happened when some people say that they have "baked the textures" into a model for better performance.

If you are using a model format that supports separate materials and textures on the same mesh (as Celestia's CMOD format does), once you've combined several meshes that originally were defined with different materials, it would be *extremely* difficult to modify how those textures were mapped onto the merged model.

[Boux]

Here is the result of a work in progress thanks to Selden's script.
It is a huge an magnificent model:
303,030 triangles
- 1842 materials
- 20.3 Mb binary cmod file
- lots of emissive textures
It is a beta Celestia conversion from Rick "Hobbes" Snider creation.
There is still a lot of work to be done.
When I am ready, I will ask the creator to grant permission for release for use in Celestia.

[ElChristou]

...If you are using a model format that supports separate materials and textures on the same mesh (as Celestia's CMOD format does), once you've combined several meshes that originally were defined with different materials, it would be *extremely* difficult to modify how those textures were mapped onto the merged model...

Well for now you have probably noticed that all my models are almost without textures... The reason of this is simply that a texture and a good mapping are not so simple to do so as I don't have so much time to dedicate to Celestia I prefer concentrate myself on pure modelling...
Perhaps mmuuuch later I will contemplate this kind of consideration...
Tx anyway for the advice.

[ElChristou]

Here is the result of a work in progress thanks to Selden's script...

Seems to be a pretty nice model

[selden]

I've added a section describing my understanding of how textures relate to models in Celestia. I'd appreciate any comments or corrections.

[Bluespace]

Thanks For It
it's so long i've been to the forum, good to see you again, now i've got some free times and is planning to do my 1st modelling (something simpler)
so thanks again for the link especially ur contrib page http://www.lepp.cornell.edu/~seb/celestia/index.htm
l it's really a great resource indeed