Hi there,
I've got a landscape that i've made from a NURBS grid, that it's all nice and ridges and polygon-joints are nice and smooth when i come to render…I want to shade some parts of the landscape with one shader and other parts of the landscape with another shader, but it wont let me, for some reason it will only let me shad ethe whole thing in one shader. Is there something i've done wrong or what?

You don't say how you've applied the shaders?

Basically though you can add shaders to different parts of an object using a shader sop. This lets you specify which primitives get which shader. The thing to watch is that you can only add one shader per primitive.
So if your entire landscape is made from just one NURBs grid you can only add one shader to it.

Fair enough…cheers for the reply.

There's nothing stopping you from doing a conversion to polys, however, and applying afterwards. Just display the NURBS for speed, but render the polys.

One way I might approach this instead, however, is to create a point attribute that I could apply over the surface. You could paint it on with the Paint SOP, and then rename it to something you could reference in a VOP shader to determine the degree you would like a particular aspect of the shader to shine through. For instance, in the shader you could blend snow caps, with treeline, with grass based on this variable(although it would probably be easier to have more than one attribute - one for each). I described something like this about a year ago in one of the (currently closed to posting) forums - maybe do a search for some of these terms and as I recall it went into a little bit of detail. I'll bet there's a tutorial that describes something like this somewhere, though.

Cheers,

J.C.

hey J.C.,

are you talking about this one…?

http://www.sidefx.com/forum/viewtopic.php?t=2187 [sidefx.com]

Yep - thanks Deecue…

Cheers,

J.C.