Here is a project that I have been using as a test bed for a rock model and for a single thunderhead cloud idea that I have been working on.
The rock is created in Cinema 4D and uses the relief tool to make the 3D object. The tool uses an image to create a 3D relief. Which can be warped into the shape of a rock or log or whatever your image happens to be. The cool thing is your can map that same image to the model and all of the color in the image corresponds to the bumps and ridges.
My single thunderhead idea is on that I have been toying with for a long time (As many of us have). It consists of a single Cumulus cloud layer that is placed by an image shader. The density fractal for the cloud layer has the image shader attached as a blend shader which allows you to place the cloud where ever you want. The Image map is set to the "Plan Y" projection and the origin position is set to center. The image map (mask) can then be used to position the cloud using the x,z coordinates and the size of the clouds footprint is set by the scale factor. The image is a black and white free form shape that has a heavy Gaussian Blur applied, this gives a nice soft transition between black and white and keeps TG2 from creating a cloud with stark hard edged boundaries. The soft edge feathers the clouds boundary making it look more natural. The density fractal can be adjusted to give the cloud the body you want it to have.
I have included a zip file that has the cloud .tgc and two image maps in this post.
