Floor not being lit in preview

warren.williams1_2beb152ec0

I have a spotlight shining down on a spider - the spider is being lit by the spotlight but the floor it sits on is not and no shadows are falling onto the floor either. The floor is just a uniform shade.

I tried bringing in a plane and removing the floor and that works fine. The plane gets lit by the spotlight as I would expect the floor to be.

So for some reason the floor is invisible to my spotlight.

Can anyone help?

Richard Haseltine

Shadows don't appear in previews, unless you are using the nVidia Iray mode. is the floor from a set? Dose it have ambient colour non-black, with non-zero strength, in the Surfaces pane?