It will be nice when the skydome can accept procedural shaders, but it is possible now to get an equivalent result. Just build your procedural shader on a sphere primitive and export the primitive in OBJ format, checking the "convert procedural to texture" option with a 2x1 ratio for the image dimensions. Then open the scene in the properties box, find the texture map you just created, and make it a skydome. This first picture uses only one direct light, with skydome vertical tiling set at 2 for the horizon effect.

The procedurals I used are deep mixtures of cellular and tubulent functions. I set the OBJ texture export dimensions at 2048 x 1024 in order to retain detail, and avoided using JPEG, which would have made the sky blocky.

Use interpolation in the skydome map settings to smooth pixels. You can play with the tiling settings to concentrate the sky within the viewing frame. The previous image used only global illumination from the skydome. This image uses both the skydome and a direct light for illumination. In each picture, the sphere shows you the procedural shader used for the skydome map in that picture. I'm sure this group could come up with more impressive skies than these. SMcQ

Quite cool. Any chance we can get a look at one of the shader trees used to make those procedurals?

I agree! A post of your shader trees would be cool. Nice trick! -Kix

I hope someone can post a sky shader with a thundercloud look, cumulus nimbus.

There must be a better way to put this referenced shader into the background. Improvements welcome. SMcQ

Nice trick, Steven ! But personally i prefer not to convert the procedural shader to an image map, instead i build my skydomes the "old way" with a big sphere on which i apply a procedural shader . It allows to animate the sky and it saves RAM too . Here's how i set up my skydomes environments : - new scene - insert an infinite plane . This will be the ground . - insert a sphere - open the Properties tray - disable the Casts Shadows checkbox - click on the clap icon to get to the Motion/Transform tab - set the dimensions of the sphere to something around 1000 x 1000 x 500 inches - set the X,Y and Z centers of the sphere to 0 Then i create my procedural shader : zero in every channel except the Glow channel where i put my clouds . The shader i've used here will be included in my upcoming shader pack called "Lots of Shaders!" . To be released soon ... if nothing comes in the way ;) litst -----> http://www.chez.com/litst

litst, Nice wispy cloud! I've used that same approach in the glow channel of a mesh dome, and can see the advantages. However, I discovered a quirk of GI rendering when I've used big spheres surrounding a scene -- the photon intensity actually increases in the areas that should be deep in shadow. It is most noticable with objects that have deep recesses. The skydome approach avoided this problem. I'm not sure I'd want this bug completely removed, as it can create some startling effects. Here is an example, with the illumination in the glow channel and the surrounding sphere made invisible. The shapes are 2 macromolecules very close together. You can see that the light bounce (white source) gets more intense where it should be darker. I'm not sure if this effect owes to making the surrounding sphere invisible, but I wanted a way to avoid the problem if it does crop up with visible illuminating spheres. Would be nice to have this reversal as an option when needed. SMcQ

Nice effect !!! I love this forum ! It looks like an anosotropic shader :) Something i'd like to see in CS3, BTW . I'll look for this bug, on my experience, there has been no big difference between a Background skylight an a skydome made with a big sphere .

litst, Look under the ball in your picture with the wispy cloud. There is a rust colored area that I suspect is not a shadow but rather, an accumulated light bounce with intensified color taken from the sand texture. SMcQ

Hum, i'm pretty sure this comes from the lightning of my scene ...

litst, Yeah, I know it sounded goofy to suggest that a darkened area could be due to bounced lighting, but the effect itself was so goofy that I wondered if it could concentrate color without additive luminance. But no. So far, this seems a candidate for an article in the "Journal of Non-Reproducible Results." There were some special circumstances for the reversed intensity rendering posted above, and the cause likely will be found in those circumstances. At any rate, there seems to be no bug when the illuminating sphere is visible. So your sphere method (which I use myself, admittedly) is more straightforward. The main advantage in using the method I outlined above for converting a procedural to a texture map for the scene skydome is that the tiling option can be used to concentrate clouds and create a nifty horizon effect. I don't see anyway to tile a procedural shader on a sphere, do you? SMcQ