Is there a way to have a prt hair object cast shadows on geometry and then have this in the render or as a seperate element? thanks!
Yes, you can save the shadows cast by particles onto Matte geometry using the Krakatoa Shadows Generator, then load the shadow data using it and render in most Max renderers (Scanline, VRay, finalRender), except for mental ray.
Tutorial (not about hair, but the principles are the same since Krakatoa renders Hair as particles):
thinkboxsoftware.com/krak-sh … -geometry/
Documentation:
thinkboxsoftware.com/krak-shadows-generator/
thinkboxsoftware.com/krak-sh … orer-util/