Workflow for creating procedural sand dunes (maya)

Hi I have a question I was wonder someone could help with.

I am creating a sand dune simulation, and so far I am having fairly good results with displacement generated by maya’s built in water system to create smaller ripples / details on the dunes. In order to complete the effect, I need these ripples to appear only on one side of the dune (the wind facing side). If anyone had any thoughts on how to control the displacement effect based on the slope / direction of the sand dune I would be grateful if you shared that information:)

Thanks!

Shane

How is it applied?
Can you apply it only to geometry whose normals face in a particular direction?

I apologize for being vague, but I haven’t worked with Maya in years.

HMM thats a good idea… I guess I can, I am using a slope shader to get all the areas thats are have an angle > X, then I guess I would need to retrieve the normal direction of the faces using one of the sampler / lookup nodes… yes, that should work!

thanks:)

You can just use a Snow shader: adjust the placement3d of the snow node so that it’s local Y points in the direction of your wind. You can pipe a shader network ‘windy side’ into the ‘snow color’ attribute and a separate ‘non-windy-side’ network into the surface color attribute

nice theodox! thats really great idea. I thought about the snow shader, but It never occurred to me I could adjusting the placement3d node! that makes a lot of sense!