Ken wrote:
> 
> Follow ups to .general.
> 
> "mr.art" wrote:
> >
> > What was causing me problems went like this:
> > #declare texturename = texture{...}
> > object{... texture{texturename turbulence value}}
> > It had worked in one of the old pre povwin versions.
> > When I dug out an old scene file, this started giving
> > me problems. I had used a different turbulence value
> > for different objects.
> 
> Art,
> 
>  Ok. I tested the following in POV-Ray v2.2 and it did render as you said
> it would. It would not render in POV-Ray for windows v3.1g watcom. Perhaps
> it is a bug or was dropped to facilitate some other preferable funcionality
> when POV-Ray v3.x was introduced. It might be related to the way the
> turbulence modifier is not allowed in a patterned texture except after
> all other modifiers are presented (illustrated at bottom of this message).
> 
> Either way lets see what the Gurus have to say about it.
> 
> Example:
> 
>   light_source{< 0,0,-5>color rgb<1,1,1>}
>   camera{location<0,0,-3>look_at<0,0,0>}
> 
>   #declare T1 =
>   texture
>     {
>       pigment
>        { bozo
>          color_map { [0 color rgb<.5,0,0>][1 color rgb<1,1,1>]}
>        }
>          finish
>          {
>            ambient .4
>            diffuse .4
>          }
>      }
> 
>   sphere{<0,1,5>,1 texture{ T1 scale .5 turbulence .5 }}
> 
> 
> > Ken wrote:
> > >
> > > "mr.art" wrote:
> > > >
> > > > I know that this is a new user sort of question, but
> > > > I haven't found the answer in the FAQ section. (yet)
> > > > The Docs say that turbulence can be used in a texture.
> > > > When I try, I get an error. What's up?
> > >
> > > It is dependent upon location in the texture.
> > >
> > > This will not work
> > >
> > > texture { bozo turbulence .5
> > >  texture_map{
> > >              [0 T1]
> > >              [1 T2]
> > >             }
> > >           }
> > >
> > > This will work
> > >
> > > texture { bozo
> > >  texture_map{
> > >              [0 T1]
> > >              [1 T2]
> > >             }
> > >            turbulence .5
> > >          }


Here's the texture syntax from the docs

TEXTURE: 
      PLAIN_TEXTURE | PATTERNED_TEXTURE | LAYERED_TEXTURE 
PLAIN_TEXTURE: 
      texture { [TEXTURE_IDENTIFIER] [PNF_IDENTIFIER...] [PNF_ITEMS...]
} 
PNF_IDENTIFIER: 
      PIGMENT_IDENTIFIER | NORMAL_IDENTIFIER | FINISH_IDENTIFIER 
PNF_ITEMS: 
      PIGMENT | NORMAL | FINISH | TRANSFORMATION 
LAYERED_TEXTURE: 
      NON_PATTERNED_TEXTURE... 
PATTERNED_TEXTURE: 
      texture { [PATTERNED_TEXTURE_ID] [TRANSFORMATIONS...] } | 
      texture { PATTERN_TYPE [TEXTURE_PATTERN_MODIFIERS...] } | 
      texture { tiles TEXTURE tile2 TEXTURE [TRANSFORMATIONS...] } | 
      texture { 
      material_map{ 
      BITMAP_TYPE "bitmap.ext" [MATERIAL_MODS...] TEXTURE...
[TRANSFORMATIONS...] 
      } 
      } 
TEXTURE_PATTERN_MODIFIER: 
      PATTERN_MODIFIER | TEXTURE_LIST | 
      texture_map{ TEXTURE_MAP_BODY } 

As you can see, a pattern modifier (such as turbulence)can be applied to
a
patterned texture but not to a plain texture. A simple texture
containing a
patterned pigment is still a plain teture.

Did v2.x have patterned textures? I can't remember and I don't have a
Linux
version of any early versions.

Goes to show, all scene files should use the #version directive, you
never
know how long that file will be around.

Cheers, PoD.

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