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avkills
07-19-2006, 11:06 AM
Anybody have any ideas. Actually I am just trying to simulate a atmosphere around a planet; true volumetric volume would be real cool.

Maybe nodes and APS?

Unfortunately, I am on the road working a show, so my dongle is at home on my G5. But so far 9 is very cool; even though I have just been messing around with stuff in discovery mode.

-mark

Karmacop
07-19-2006, 10:38 PM
I guess the best thing to do is make an object slightly larger than your original object, and put a surface on it that uses incidence angle with a gradient, but you could do this with layers so it's nothing amazing. Nodes will let you do more but it's the same old trick :)

starbase1
07-20-2006, 05:44 AM
Yes, that's what I have been doing. The old method does have it's issues though, like when you get very close.

So it's a good question - does LW9 offer a better way of handling airglow?

avkills
07-20-2006, 06:08 AM
starbase1,

Yeah I have been just messing around just to get a feel to how I am going to re-vamp my hi-res earth object in LW9 using nodes. BTW my test with clouds looked really good, I made a subdivided sphere and rendered it with around 1 million polys using a ridged multi-fractal being driven with the nasa cloud map.

Since I am still on the road though, and using everything in discovery mode, it has been kind of hard to truly judge everything with the water mark.

I fly back Friday, so I will have time to work on it Friday night and Saturday morning. I have a feeling I will be using a combination of nodes and traditional shading for the entire model (which for me is 4 objects).

-mark

starbase1
07-20-2006, 02:57 PM
Avkills,
Have you tried normal maps yet? There's a thread near here where I show what i did with the Moon and normal maps - it is SO close to faking the geometry, I was seriously impressed.

I am going to try it with Earth this weekend.

Although it is being mainly sold as a way of keeping poly counts low, it is very good indeed for planets - well, so far!

Nick

avkills
07-20-2006, 06:43 PM
I did some testing using APS and a standard displacement map. NASA has a elevation map you can download, so I am using that for the bump and making the max value scale to however high Mt. Everest would be in respects to the size of my earth object. Seemed to work very well. Before v9 I was just a standard displacement map without APS with a high poly sphere. APS will make this a lot better since the extra APS polys do not really croak the render.

-mark

starbase1
07-21-2006, 12:15 AM
I'll be VERY interested to see your results!

Incidenttally, the best place I have found for high res normal maps is the Celestia Motherlode.

Nick

petrockproducti
07-21-2006, 12:47 AM
Howabout using some of the spiffy new transparency and refraction shaders along with the incidence work. An atmosphere is essentially a large volume of air. Air has a refraction value that distorts over certain distances. If you added a transparency shader with an air object, that might provide that realistic /volumetric pop.

jameswillmott
07-21-2006, 12:55 AM
Has anyone tried a Null and Hypervoxels in volume mode?

starbase1
07-21-2006, 12:58 AM
Howabout using some of the spiffy new transparency and refraction shaders along with the incidence work. An atmosphere is essentially a large volume of air. Air has a refraction value that distorts over certain distances. If you added a transparency shader with an air object, that might provide that realistic /volumetric pop.

Yes, and also an element that will make it brighter when backlit.

starbase1
07-21-2006, 01:00 AM
Has anyone tried a Null and Hypervoxels in volume mode?

Some time ago I did, for gas giant planets. One big HV did not work at all well. I had somewhat better results by taking a slightly shrunken planet, and applying HV's to the points so they justcame through th urface. But render tims were a bit of a pain, and I don't think it was better than the gradient air layr I have...

avkills
07-21-2006, 07:31 AM
Howabout using some of the spiffy new transparency and refraction shaders along with the incidence work. An atmosphere is essentially a large volume of air. Air has a refraction value that distorts over certain distances. If you added a transparency shader with an air object, that might provide that realistic /volumetric pop.

That is a possibility since the new incidence node can cover 180 degrees now. But so far with my tooling around, I have had better luck just using the standard surfacing method; it is a little more straight forward than the nodal method. I just need more time to mess with it.

-mark