Creating More Complex Man-made Materials - Blender 2.6 Cycles: Materials and Textures - page 196

How it works...
From step 1 to step 7 we built the basic shader for the leather material; obviously
there is not strictly the need to mix two different colors via RGB nodes inputs, one
could be enough, but this way it can be easier to obtain certain hues.
From step 8 to step 19 we built the bump pattern for the leather. We used two differ-
ent Bump nodes with different values for the Diffuse and Glossy and for the Aniso-
tropic shader, to have slightly different light reflections on the surface.
Note that we used the UVMap layer information of the mesh for the Tangent node
to be connected to the Anisotropic shader, and the Object mapping mode for the
bump textures, instead; actually, because the mesh had been unwrapped already,
we could have used the UV mapping output for the texture nodes too, but in that
case the scale values for all the nodes would have been double and the flow of the
textures on the polygons different (because forwarded by the flow of the unwrapped
faces in the UV window).