Phobos impressions

[danielj]

But tesselation is only available in Direct X 11,in video cards like GTS 450 or Radeon HD 5750 and above.Did you change your video card recently?

[t00fri]

But tesselation is only available in Direct X 11,in video cards like GTS 450 or Radeon HD 5750 and above.Did you change your video card recently?

What?

Tessellation is a most general expression in mathematics, actually. Here is a link from the math forum that defines quite nicely what tessellation means:
http://mathforum.org/sum95/suzanne/whattess.html

In the present case it just meant that I connected the vertices (= (x,y,z) points) by suitable lines to form triangles. Here you see an illustration of this tessellation for Phobos:



This was achieved with a simple Perl script using the published vertices as quoted above.
It's a standard way of making model surfaces in 3D.

And NO,no,no...I didn't change my video card. Mine is over 5 years old (FX5900Ultra/256 MB). It is much less fancy than the cards you are using recently.

Fridger

[John Van Vliet]

--- edit ---

[MiR]

Fridger, John,

Thanks

I understand now what you mean; the different maps belong to the different models...

Right now I'm still learning to deal with .pds files (lbl, tab, fit...)

Regards
Michael (I'm sorry for the delay)

[t00fri]

Fridger, John,

Thanks

I understand now what you mean; the different maps belong to the different models...

True, but only one (mine) relies on published scientific work. If this is not important for you, then you have to use your artistic preferences.

Fridger

[MiR]

Fridger,

True, but only one (mine) relies on published scientific work.

No doubt about it.
John himself has recommended your model.

I must repeat: My Intention is to make the appearance (colour and texture of the map) of Phobos a bit more realistic. The current one (in Celestia) looks something strange; a bit like a drawing draft.
And that's all.

I will do this work as well as I can.
But first, I'll orient myself to the maps which are already exist. Hoping that after this work only smaller corrections will be necessary.

Your comments are very helpful and always welcome.

Regards
Michael

[t00fri]

Fridger,

True, but only one (mine) relies on published scientific work.

No doubt about it.
John himself has recommended your model.

Once more: its not my model! It's released by a scientific team specializing on Phobos research.

I must repeat: My Intention is to make the appearance (colour and texture of the map) of Phobos a bit more realistic. The current one (in Celestia) looks something strange; a bit like a drawing draft.
And that's all.

My 4k Phobos map does NOT look like that. It is computer-colored with a true-color photographic template. I hope you know how this technique works in GIMP. The map also implements the latest available texture data.

Here is a 5.7 times reduced 0.7k image of my 4k Phobos texture that people are welcome to use instead of the default Celestia texture.



Fridger

[MiR]

Great

But... should I stop my work at the Phobos map now

Michael

[t00fri]

Great

But... should I stop my work at the Phobos map now

Michael

that's not up to me to decide, of course. You may continue with Phobos and practice various image manipulation techniques with GIMP, for example. You may also turn to other bodies where lots of work still needs to be done.

The reason why I would somewhat recommend the second option is that working on Phobos requires BOTH to work on the texture AND --in parallel-- on the underlying model. Modifying the texture means mostly also modifying the model to pertain (ar achieve) a perfect matching of texture and model. Working on the model requires solid experience with tessellations and Perl (-> me) or considerable know-how with Blender (-> John)

Fridger

[MiR]

Fridger,

You may also turn to other bodies where lots of work still needs to be done.

Oh yes, I've already planned this... but step by step.

The reason why I would somewhat recommend the second option is that working on Phobos requires BOTH to work on the texture AND --in parallel-- on the underlying model.

That's not a good reason. If I would think this way, I could pack my bag immediately.

So let me continue with this work (with your scientific supervision, I hope).
Because, I'm used to it to bring my work to a successful conclusion... (maybe more or less, but with a result.)

And, please remember the title of this topic; my work on the Phobos map is only an impression. Yours is scientifically...

Michael

[MiR]

...the work is still in progress. Unfortunately, I haven't enough spare time currently.
Please be patient...

Michael

[chris]

I have uploaded a high resolution model of Phobos (in Wavefront OBJ format) here:

http://www.celestiaproject.net/~claurel/celest ... 512.obj.gz

The model is huge (over 3 million faces) and really should be translated to binary cmod for fast loading. I generated the file from a SPICE shape kernel found here:

ftp://naif.jpl.nasa.gov/pub/naif/generi ... sk/phobos/

There is very little information about how the SPICE model was generated. In fact, the only comment is that it is for demonstration purposes. Nevertheless, there is an impressive amount of geometry detail. In the screen shot below, there is no texture or normal map; every detail is a result of geometry:

phobos-high-detail.png

As far as processing, the vertices and faces are translated directly from the SPICE kernel using a special utility that I wrote for the purposes. The only additional processing was surface normal generation. I also translated the model of Steins and comet Churyumov-Gerasimenko. I'll upload those shortly.

--Chris

[MiR]

Thank you, Chris,

this is great. An optimal basis for the new Phobos map.

Michael

[Hungry4info]

Well clearly I've overlooked something as the .ssc file doesn't seem to recognise .obj extensions.

Any advice on how to turn this into a CMOD? (I apologise if this is a newbie question... you'd think from my post count, I'd be able to sit down and just write out the Celestia source code by now... )

[John Van Vliet]

--- edit ---

[Fenerit]

Well clearly I've overlooked something as the .ssc file doesn't seem to recognise .obj extensions.

Any advice on how to turn this into a CMOD? (I apologise if this is a newbie question... you'd think from my post count, I'd be able to sit down and just write out the Celestia source code by now... )

The CMODview is for you. It convert 3DS and OBJ to CMOD.
http://www.shatters.net/forum/viewtopic.php?f=25&t=15775

[Hungry4info]

Thanks.

[MiR]

Hi,

I have some (newbie) questions.

I can load the phobos mesh (converted by Chris) in Celestia.

Now I have the problem to specify a surface texture. But not the solarsys.ssc entry. It seems to me that the mesh itself needs a specification...?

So, what sort of software do I need? => I was trying to do this with Anim8tor; nothing happens. With other models I haven't any problem to define a surface texture in that program...?

With cmodview I'm able to convert the file to .cmod but I'm unable to make any changes. The Material Editor make some changes, but don't save these...

Another question is: What software can convert the file to ascii...?

I've read this discussion here: http://shatters.net/forum/viewtopic.php?f=23&t=16378
Like Selden I can see all these files from Chris in Celestia. But without a surface texture...?

I would like to use this model for my phobos map. Otherwise, I will focus my further work on the standard version.
Because I think the maps from Fridger and John belong to their models.

Thanks for help

Michael

[Fenerit]

Michel, for what concern Chris's Phobos I do not know about it since I've not downloaded it. But I've played with Steins, so I can say that the models lacks of the UV mapping and of the normals, whether you wish to assign the texture through SSC as well as from the relevant "..textures/medres" folder. If this is the case, do load the model into the program as OBJ and apply on it the UV mapping (I do not know how Anim8tor handle such operation). Once done this, you can apply whatever texture on Phobos, even the your. When then is time to re-convert the model to CMOD, either do use the Anim8tor plugin exporter or the CMODview (always make the "generate normals" operation. For what concern the "generate tangents" they are required whether to Phobos you apply also the normalmap.

The software for converting CMOD in ASCII and BINARY as well as among them, is here:
http://www.celestiamotherlode.net/catalog/utilities.html (3DS to CMOD converter)

[MiR]

Thanks Massimo, this could help...

Michael