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View Full Version : Inquiry - Mars 3-D terrain - Highest quality Possible - Buy or Make ?



wtdedula
02-14-2005, 05:20 PM
Hello All;
I need some recommendations and sugggestions from the Lightwave Professional Community.

I work at the NASA/Glenn Research Center in Cleveland, Ohio and am in need of a very high quality 3-D model of the full terrain of Mars to use in an Immersive and Interactive Simulation. In the simulation, it is possible for us to get fairly close to the surface (I'd say 30-feet away) anywhere on the planet Mars and it has to look as realistic as it can.

This afternoon, I spoke to a Mars geologist and he said that in order to develop terrain that looks good at 30-feet, the surface appearance must be "guessed at" by using fractal noise or some other method.

My question is in two parts ...

First ... does anyone know if anyone has developed terrain yet of this high detail (Of the entire planet) and has offered it for sale ? Since we're planning to distribute this application to the public, eventually, the license agreement has to permit this. If you can provide a web site or phone number, that would be awesome. Btw - I am currently investigating if any group at NASA has done this but even though we originally acquired the data, it may be unlikely that someone here would have actually assembled it into a finished 3-D terrain map unless there was a particular research project where it was actually needed.

Second, and perhaps even of more interest, If I were to create such a high-resolution terrain map of the entire surface of the Planet Mars, can anyone give me some guidance as to the steps I would follow ? I believe I know the basic steps - load (Into Lightwave) each chunk of digital elevation data from the Mars Global surveyor and assemble all into entire terrain surface then apply a surface texture. Of course, until I begin trying, I'm sure I'll run into some problems such as loading the machine with a ton of polygons. I have located a source for high resolution Digital Elevation data from the Mars Global Surveyor (MGS) at a resolution of 128 Pixels/Degree. Is it appropriate to use this high a resolution or could I get similar results at a lower resolution (say 64 pixels/degree or 32 pixels/degree) ?

Is there any tutorial on the web that specifically addresses the steps to load in Digital Elevation Data (Preferably Mars but even Earth for that matter) to create the highest quality product even including texture map the way a professional modeler would ?

Thanks.

Tim

Lightwolf
02-15-2005, 04:04 AM
Hi Tim...
ouch, that "Immersive and Interactive Simulation" bit made me cringe...
Will you need that high a "pseudo" detail for every part of Mars, or just for a certain area?

Basically, if you need it for an interactive simulation, that calls for a bit (actually a bit more ;) ) of custom programming. Isn't there a similar viewer for earth out there distributed by NASA? Yep: http://www.andesengineering.com/BlueMarbleViewer/ This might be a start for your.

AFAIK the best Mars data is available for NASA, so you're sitting at the source already ;)

Cheers,
Mike

starbase1
02-15-2005, 04:15 AM
Well, the polygon count is going to be, er, astronomical!

But your friend is correct, to get close enough you will need to interpolate and roughen the available data.

Much as I love it, I'm really not sure that LW is the best tool for this job, as that kind of fractal roughing is really pushing it a LOT. And dedicated landscape packages tend to be much more efficient.

I've mucked about with this and you are talking MOLA data really, no other options. The best stuff I have seen using this is at space graphics - see

Space Graphics Web Site (http://www.space-graphics.com/)

He has done a LOT with whole mars models, and they look georgeos. Also some of it is using LW, though not at the kind of resolutions you require. LW models and others are available for free download.

He's a very helpful guy, passionate about the subject, and I am sure he'd love to be involved!

:)

Let us know here how the project progresses!

wtdedula
02-15-2005, 05:49 AM
Hi;
Thanks for all of your helpful suggestions and recommendations.

Basically, I want to create the terrain at the required resolution and then have a developer develop custom software to page in and out textures as required.

I agree that lightwave may not be the best tool for the job. I know there are custom terrain generation packages out there.

I have been to Space-Graphics.com and I agree his stuff is awesome though I don't know if it is as detailed as I need to get. I will investigate.

I am currently investigating if we have done any work to create any whole Mars terrain 3-D models.

If anyone has any other suggestions, I'd be interested in hearing them.

Tim

Lightwolf
02-15-2005, 05:58 AM
Hi Tim,
Paging in the texture will be only a part of you problem (not the smallest one, agreed). It would make more sense if the mesh was generated on the fly by the software as well, using some kind of LOD based algorithm like ROAM. Check out www.vterrain.org for a couple of approaches.
So you'd basically use the highest res data you can get your hands on as the base, and then algorithmically interpolate to a higher res when the user zooms in closer.
I frankly see tons of 3D programming work there, but hardly any "graphics" work, except for preparing the original elevation map.

Cheers,
Mike

faulknermano
02-15-2005, 06:32 AM
do you think normal maps will help in memory management? just a thought, in case you end up having too many polys. :)

Anatoly Zak
02-16-2005, 12:06 PM
Hello All;

I have located a source for high resolution Digital Elevation data from the Mars Global Surveyor (MGS) at a resolution of 128 Pixels/Degree. Is it appropriate to use this high a resolution or could I get similar results at a lower resolution (say 64 pixels/degree or 32 pixels/degree) ?

Tim

I think right timing for such project is also important. This year NASA is launching a new satellite of Mars with super high-resolution mapping camera, possibly making Mars Global Surveyor's cartographic data absolete within a year.

Anatoly Zak
RussianSpaceWeb.com

pdrake
02-16-2005, 09:26 PM
not that i want to promote other software on this site, i know that's against the rules, but with a poly count as high as what you might encounter, you might want to look at electric image to do the ground and lightwave (keeping it on topic) to do details for compositing.

i have alot of personal experience with electric image and it handles millions of polys with unbelievable ease.

mattclary
02-17-2005, 08:41 AM
ALL of Mars? Why didn't you pick something easy, like cleaning the Aegean stables? ;)