View Full Version : Creating realistic cloud layer for planet

03 March 2010, 02:23 AM
I've tried several techniques.

I started out with fluids and added some good looking incandescence and noise textures.
This is all well and looks really good for a standard cloud render.

However, i have tried using paint fluids and getting the clouds to cover a sphere as a cloud layer.

The render i need is a orbit scene so i need a good cloud layer with depth, so using animated textures on a sphere is'nt gonna hold up for close inspection.

Also looked into using displacement and then converting that displacement into polys (displacement taken from infrared cloud imagery, i do recommend for other cloud texture as bumps to look into these. They are really nice)

However i don't get that nice cloudy feel to them, from space u don't really see much movement in the clouds, but there is a little, some swirling and drifting of cloud banks, which is what i need.

So i am open to suggestions or tips on how to get a good result on this.


04 April 2010, 02:31 AM
You could think about emitting either cloudy particles or fluids from a texture so you could still use one of your satellite maps for that. Im not sure what kind of detail you are after but its always going to be a struggle for your system when rendering volumetrics with hundreds of thousands of cloudy particles. If you went to use fluids you'd have to compile the simpleFluid emitter for a start and use a fairly hi res container with hi frequency texture.

or just a thought, sprites using deep shadows.

04 April 2010, 07:49 PM
great ideas. Just need to get started on that fluid emitter.

Once did a picture of a man dissolving using texture to drive the emitter, i assume u have something similar in mind to drive the fluid density?


04 April 2010, 08:12 PM
Not sure if we are on the same page, did you import the image into the paint fluids density method or actually create a fluid texture emitter? I was meaning the latter method.

04 April 2010, 08:13 AM
I did a scene like that once. Rendering Earth from orbit doing the clouds with different techniques and comparing the results with NASA images. To be honest, I didn't need to put much "volume" into the clouds since when seen from space, they are very very thin. A simple (and very low) bump map and some shading work with ambient and diffuse did the trick. One other thing that really helps is to use 2 layers of cloud textures, one for the "thicker" and lower ones and another for the "thinner" and higher ones.

The animation is pretty easy. You just take one of the hundreds images you can get on the internet for free (I think 16k was the biggest I found) and you do some really small and slow distortions using a grid warp in nuke (or shake or whatever app you may use).

I promise you, you don't need much volume. From space, even the displacement of mount everest is only a few pixels thick.

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04 April 2010, 08:13 AM
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