UDK Clouds

[Habboi]

A classic question I'm sure. I want to make some nice looking clouds for a scene I'm slowly working on that's set high above the clouds. Basically floating island.

So what's a floating island without some sexy clouds. How would I go about achieving this effect? Perhaps a non expensive method since I am slowly running out of precious memory. Also animated.

I have a theory though. What if I used VUE to render out a texture with realistic clouds and just used that with a scrolling node in UDK. It'd still look flat though.

http://i1.trekearth.com/photos/4716/above.jpg

I used this tutorial and it came out fantastic but it's flat. Besides this method and particles, is there a clever way of perhaps baking this out.

http://www.chrisalbeluhn.com/UDK_Mist_Fog_Tutorial.html

[TeriyakiStyle]

What 3d software are you using?

My first guess might be:
http://farm7.static.flickr.com/6030/6201430538_429659d151_o.jpg
Use an image like this, RGBA where each channel is a cloud pattern, tiling. Then pan them over eachother in a cloudy material in udk. You could then apply that to a tile-able piece od geometry that is an animated wave. Finish that with some alpha cards of whisps to break up the edges.

The very distant clouds could be a horizontal bar of slowly animated clouds. Basically a ring in front of the skydome.

BUT... That is possibly an older and cheaper method. There might be more innovative, cooler ways to pull it off.

[d1ver]

A set of greyscale cloud diffuse maps + their respective normal maps(you could try to extract them from the photoshop clouds or even sculpt). Set them panning over each other with some additional bump offset(could try from diffuse) and some WorldPositionOffset to create some real motion. And then a particle emmiter inside of it to create some smoky wisps flowing on the surface.
I think that that's How I would go for it. Though if you really need to optimize you could try to drop bump offset or vertex offset. Also one normal map could've been enough or you can even remove blue shannel from the NM and put 2 greyscale clouds in the blue channel and in the alpha.
I hope this random train of thought comes in handy. Good luck!

[Eric Chadwick]

That, along with some Offset or Parallax mapping, could do the trick
http://wiki.polycount.com/ParallaxMap

[Vailias]

IF you make your maps bigger than in that tutorial, add a 4th cloud map, make that one really big and panning slowly, then plug it into mesh displacement.

Apply the material to something other than a plane and you'll get results more like what your picture shows.

[passerby]

you should have kept looking on the same site for tuts.

http://www.chrisalbeluhn.com/UDK_World_Position_Offset.html

even uses your fog for the exmeple.

also experiment with making little wisps of mist in cascade and put some particle emitters under the whole thing.

[Habboi]

Thanks all. I shall jump in and experiment with your advice.

[haiddasalami]

http://stephenjameson.com/tutorials/faking-volumetric-effects/ Damn the link is down :(

Thank you wayback

http://web.archive.org/web/20100528163256/http://stephenjameson.com/tutorials/faking-volumetric-effects/

[Habboi]

Thanks, that's insanely useful and difficult :) I look forward to the challenge.

[Habboi]

Hey guys just letting you know that I've been experimenting with it and this is what I have so far.

www.youtube.com/watch?v=s-sPx7II1I4

http://upload.habboi.co.uk/clouds.png

Anyway I was looking for other examples that people have done and the best result by far is this post by Neox: http://www.polycount.com/forum/showpost.php?p=995132&postcount=344

I asked him how he did it and he said:

"It's a modelled cloud with a fresnel to control the opacity at the borders, also it has some noisemaps to break up the fresnel opacity."

To me that's a bit too technical but I gather he modelled a bubbly shaped mesh, applied some sort of white noise map to the diffuse and used a bunch of alphas to blend it out. I'm going to give it a whirl but if anyone has any pointers I'm all ears.

[synergy11]

Nice work!

I really like the result.

A dumb question... Would this look the same if you were on the ground viewing the clouds from above?

I am going to try to set up that material.

[Habboi]

I believe so. Often while flying around I would look up at it and it looked like clouds scrolling across the sky.

Anyway lucky for you that cloud texture is already part of UDK so pretty much all of it is there for you. The only difference is that I made a nomal/spec to get a little highlight on the rims of the clouds when the sun hits it. You may find plugging the material in the diffuse is better for you, my level uses settings that makes everything super bloomy unless I do some hacks.

The only problem now is that it's on a flat plane and no amount of parralax mapping will change that. If I could just figure out a way of making a bumpy mesh that animates like a cloud then I'd be happy with it. Basically I tried the noise modifier in max but I'm stumped on how to animate it like the waves in a sea. Clouds don't rock back and forth but they do "scroll" in a direction. I just need that "bumpyness" and I'm stuck. Maybe if I have a fresh mind I can figure it out.