I’m still new to material nodes in blender,
this node would effect the material like a light or a shadow,
you would pick what angle of a mesh you want a texture/effect to be on.
i do know i could paint it with a mask but with a more detail mesh it would be a pain to make it look right.
it could be for moss on the north side of a tree or sun damage to the side of an object that is facing the window, dust settled on the top of a statue,
thank you, ill test it out.
i was just testing the map range.
and just bake a mask with it, that will work or is there a way to lock it so if the mesh is in a animation and falls over on its side the effect stay locked.
You don’t need to bake as the effect depends on the geometry object normals.
Unless I don’t understand what you want to do…
To use the Normals in the Object Space (which rotates with the object), you can use one of the following setups:
Oh, my mistake. I used the geometry node in the first post.
Sorry for the confusion. I got carried away trying to answer when I don’t really understand anything about shading in blender 
@Secrop 's answer is much clearer.
where is delete.
sweet, texture coordinate fixed it.
There’s also other alternatives to the ‘Normal Node’… for example, this will let you use an external object (an Empty, in this case) to change the orientation:
that is cool, there is so much to learn.
