Hello,

I am one of the many Softimage users applying himself to learning Houdini.

I feel sure the following problem is one of attributes and variables and how to apply them in the different networks within the application - to which end I am studying Ari Danish's excellent tutorials on the subject.

What I am attempting is a cartoon ( flat shaded ) shader for hair such that when the hair is emitted from a part of the skin surface that fall in shadow then it will be dark and where in falls in the light it will be light.

With Softimage the solution was to use ICE strands for the hair; get the emission location; get the normal at emit location; find the dot product of the emit normal with the light direction; pass this to a gradient and get the shadow value for the hair.

I fully understand that Houdini is a different beasty so I am trying to ‘think Houdini’ to find a solution.

So far I have hacked into the standard fur shader and put down an illuminance loop, then put down the global variables node to get N ( surface normal ) and L ( light direction ) and used the dot product to pass to a gradient. Unfortunately the results aren't quite what I'm looking for…

Any assistance gratefully received…

All the best
//Simon

if you are going to do a hair cartoon shader i would advice to NOT use the hair model, instead use a constant, and use the shadows as mask for the color.

the hairs are just a flat ribbon looking at the camera, the hairs by itself dont carry the normal information, you need to make that attribute before passing it to the fur node, or the procedural fur.

then you can use the normal to do something.