Hi all!
I'm working on an Earth model with 4 nested spheres in Vue 5i. 1=Land, 2=City Lights, 3=Clouds, 4=Atmosphere

Having trouble with the atmosphere sphere. It needs to be less transparent just at the edges, so it shows up, but doesn't obscure the detail away from the edges. Setting transparency to additive helps some, but not enough. If i could set index of refraction to 0.999, that would work, but it reverts itself to 1.0 and 0.99 is not enough :o(

Maybe i need a function or filter curve? Anyone know what function would make the very edges of the head-on view of a sphere more opaque than the front? Or some way to simulate Rayleigh scattering? Have not tried volumetric atmospheres either?

Other ideas?
Extra points if i can also make the atmosphere edge fuzzy at the same time!
Thanks All!

I don't think something like that is possible in 3D really. When you turn or even move only (and change the perspective therefore) the earth - including atmosphere etc, how does any filter know to change the transparencies appropriately? What i can imagine is a disk - 2D - with a transparency map you create in Photoshop for example. There you can do what you need to do and even make the edges fuzzy.

One day your ship comes in - but you're at the airport.

Sounds like what you might be needing is a Fresnel type effect. I can't recall if V5I comes with a Fresnel filter/function, I will try & check it out.

Here a sphere is slightly transparent at the center, fading to not visible at the edges. Angle Of Incidence input node, and a filter after it to drive what angles are less visible produces this sort of effect. Obviously you'll need to fiddle like mad to get the exact effect, but it's a starting place for you.

Sorry for the spelling error - should be "opacity". Yes, "Angle of Incidence" looks possible - thanks much DMM. Thanks Wabe, i can always do it as postwork in Adobe Photoshop, if all else fails, but it would be cool to do it all in Vue.

Have you tried making a volumetric cloud like fuzzy material, that's what I use all the time for my space scenes. You just take one of your spheres, map the material to it and scale it up larger so you can see the fuzzy edges. Check my image "Tenabulus V" in my gallery to see what I mean.

Thanks nonotyrannus! I see what you mean. I'll give that a try, maybe combined with the angle of incidence function. I like your spacecraft metal texture. Is that something you made, or is it available publically? Thanks again...

That's something I made using a function I found in Vue, I can't remember which one off the top of my head, I've since refined it more for more of a metallic feel, I've attached a WIP render for the next Sci-Fi scene I'm working on, just have to get working on the additional models I need to build for it.

Message edited on: 06/01/2005 12:36

Nice model! Very credible. I see so many spacecraft models that make no sense physically or aerodynamically. Guess i'll also modify a default Vue material for the ship i'm building in Silo 3D for the Earth scene. Most of the sub objects making up the ship will be texture mapped in Adobe Phosotshop with unwrapped UV images, like parts of your model - but will still need 1 or 2 regular materials as well.

Thanks, I use Autocad to model and don't have the capability of uv mapping (since neither Vue nor Autocad will do it) so I usually break the model apart into layers depending on textures, usually as many parts as possible so if I need a part to be textured differently later on I don't have to go back and split it apart. I actually prefer this method now because it means I can change parts of the model without having to go out and change the original uv texture/mapping. Looking forward to seeing your finished earth image!

Absolutly agree about "volumetric fuzzy material". Other trick is to add a sphere between Atmosphere and clouds, a sphere with some "additive blue haze" (see capture). My 2 cents.

Thanks Phoul, but i think i just now got a good atmosphere sphere before seeing your post.

Used both a volumetric material and a function to force it to show only at the rim. Probably need to add another function to stop it from showing on the dark side. Want to review some actual Earth photos i have first.

Oh, and it's not "Additive", it's "Uniform".

Thanks so much for the help, everybody!

You're welcome.

You inspired me, thank you. Here my wip ;-

And BTW thank you for the link (maps and tricks) you shared in your gallery. :-)

I like it! Your bump map really works. Maye i'll turn mine up a bit.

Nice Work both of you! I really need to find some time to get into the Function editor more, I'm still not doing much that I wasn't doing in Vue 4 and there's just so many possibilities in there.

I agree. The Vue 5i functions, filters and materials are so powerful and flexible and complex that i doubt that even 1% of users are taking full advantage of them. Yet i've never seen better interfaces for non-programmer use. So, though they are daunting, i don't know how they could be made much easier. I guess the pros will explore and use them and the amateurs will avoid them. Sure happy they are available - and as an electronics engineering amateur, i dearly love to plug stuff together and watch the magic happen. It's real modern day alchemy, complete with magic spells and arcane knowledge - coming soon, the tombes of secret spells. Who will be the first with the "Vue 5 Infinit Functions Cookbook"?

Message edited on: 06/02/2005 14:47