#question from IRC:
#how much work would it be to be able to change things like diffuse_color _Value and Spec_intensity (multiply by input value) of aall materials of selected objects?

__author__ = 'thoth'


import bpy

def adjust_all_hues(mats):
    for m in mats:
        m.diffuse_color.h = m.diffuse_color.h + 0.2
        #m.diffuse_color.r = 1-m.diffuse_color.r

def mission1(scn):
    mats = set()
    for o in scn.objects:
        if o.select:
            for ms in o.material_slots:
                mats.add(ms.material)
    adjust_all_hues(mats)


mission1(bpy.context.scene)