stbenge <UN### [at] hotmailcom> wrote:

> I doubt they are the same bug.
>
> Check this out:
>
> height_field{
>   png"mountains.png"
>   ...
> }
>
> It works just fine, always has.
>
> Compare it to this:
>
> height_field{
>   function 513, 513{
>    pigment{
>     image_map{
>      png"mountains.png"
>      interpolate 2 once
>     }
>    }
>   }
>   ...
> }

Yeah, there are some strange goings-on in HFs made from functions.  I think I've
noticed the edge artifacts you mentioned.  But there's also the odd fact that
the applied pattern (or image_map) ends up being flipped upside down(?) like a
mirror-image, AND that the 'origin point' of the pattern/image is out of place.
The usual origin that we all know and love is at <0,0,0>; with a HF function,
the 'origin' is mysteriously at <0,0,1>, and the applied pattern/image
scales out from there. I've come up with simple workarounds to these particular
situations--but, along with the edge artifacts, it's apparent that HF functions
are not working correctly. I suppose, though, that re-engineering the
problematic code (whatever it is!) would cause lots of backward-compatibility
problems with previously-made scenes.

Ken

Post a reply to this message