POV-Ray : Newsgroups : povray.binaries.scene-files : Dakota Red Granite macro - beta #1.2 : Re: Dakota Red Granite macro - beta #1.2 Server Time
25 Jul 2021 08:32:30 EDT (-0400)
  Re: Dakota Red Granite macro - beta #1.2  
From: Bald Eagle
Date: 24 May 2021 13:30:00
Message: <web.60abe286c1167ed21f9dae3025979125@news.povray.org>
Thomas de Groot <tho### [at] degrootorg> wrote:

> Something I noticed with sslt in my settings, is that veins seem to
> become really 'thin' or, more probably, 'transparent', and thus tend to
> /disappear/ from the view except with higher magnification.

Yes, I think some of that happened in the early experiments with people applying
sslt to objects.  Some details nearly disappeared.

There should definitely be a parameter passed to the macro for width of the
vein, and frequency of occurrence.

Now that it's looking good, I'd say it's time to think about how to pass
alternative color maps into the texture - both to model other granite types, as
well as use the change to spot something in the current implementation that
might be hiding, but a different color scheme might bring out.

Piggybacking on that idea, there should be some triggerable material attribute
data output to #debug with numbered map entries, and then we could have a
mechanism to pass in a color for a single entry on-the-fly.  Then it would be
easy to plug the macro calls into a loop and render a ton of different samples
when tweaking a new material.

The macro should also top up my coffee or G&T while I'm working on a scene,
depending on the value of a required parameter.  :D

> I am trying to get a grip on how to
> tweak the translucency parameter.

The way clipka explained it that the translucency color is geared toward what
color you want the sslt effect to take on as it percolates through the material.
 So for skin, where the blood will add a red color and absorb the blue and
green, you set the color to a red-channel dominant rgb vector.

Maybe the best sslt test-bed would be a back-lit wedge of material, much like
what Ansel Adams would do with the Zone System when calibrating negatives and

Clipka also recommended in one thread to overlay the sslt texture layer with
something else and maybe(?) he specifically said to only set the sslt in the
lower layer...  I'd have to search and pull it up.

Have to head out and do some errands, so won't be back until later in case you
can't find it with a quick "sslt" search.

- Bill

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