Thank you, clipka and Jim.
I want to model not a three-dimensional, but a flat object. Like polygon, or
mesh/mesh2.
Directive
pigment{aoi}
works well, surface color depends of angle of incidence, but shadow is always
the same.
I cant found, how to make my surface cast semi-transparent shadows.
Keywords 'transmit' and 'filter' works only with 'color'. How to make texture
transparent?
