Tim Attwood wrote:
> Height_fields have depth, but only the "field" surface
> is rendered...  so you need to difference off a
> slightly smaller box to give it edges...

Thanks ok I see this works fine. It still seems a little odd.

To me it seems counterintuitive that taking a height-field and 
differencing a larger box from it leaves anything. It's even stranger 
that whats left is outside the original bounding box of the height_field

difference {
   // height_field from <0 0 0> to <1 1 1>
   height_field {
     png  "plasma3.png"
   }
   box { -1, 2 }
}

It seems height_fields could be considered of infinite depth but that 
apart from the top face their faces don't show until something is 
differenced.

   In this case I'm not interested one way or the other in any edges as 
they won't be visible so clipping works fine too, and I *think* I now 
understand how hf's behave.

Now to try to complete the rest of my Before-After 3D-rtc entry :- )

thanks

Post a reply to this message