Grass texture mystery

[Tom W.]

Something weird has happened - I'm sure someone can explain why. I inadvertently specified one of the '<Displace Map>' grass textures from the VW libraries to be the texture on the surface of my site model (inadvertent because of the render times involved + the fact the scene didn't require that level of detail) but what was weird was that with this texture specified my hardscapes disappeared from the render. This was using a RW Style. In OpenGL the hardscapes were there. And when I switched to a 'normal' grass texture (one without the image bump + displacement mapping) the hardscapes were there too.

 

In this case I was just glad to get my hardscapes back + like I say I shouldn't have selected the displacement-mapped grass texture in the first place, but surely the displacement mapping can't be the reason my hardscapes weren't displaying in the VP? What if the scene was a close-up + I had wanted to use a hyper-realistic grass texture? Be good to know what's going on if anyone knows... Needless to say I'm new to rendering.