Tek wrote:

> Interesting problem. I've just tried it out comparing 3.5 to Megapov 0.7
> (based on pov 3.1) and I think I have the solution, try this:
> 
>  normal {
>   pigment_pattern {
>    granite
>    scale <0.1, 20, 1>
>   } 0.1
>  }
> 
> I've noticed that pov seems to generate bumps by comparing samples of the
> bump pattern to estimate a gradient (by sampling a fixed distance away).
> It would appear 3.1 evaluates this sample distance after the pattern has
> been scaled, whereas 3.5 does it before the scaling. This means if you
> scale a pattern in 3.5 the bumps will appear to scale, whereas in 3.1 they
> will alter as they scale (becoming smoother as you scale down).
> 
> In any case using pigment_pattern allows you to manipulate the pattern
> before pov samples a normal from it. One trick I use is: normal {
> pigment_pattern { granite scale f } 1 scale 1/f }, so that by varying the
> value of f you control the severity of the bumps.
> 
> Hope that helps

Thanks alot, I think this may work, I am trying to set it up now...

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