"Leef_me" <nomail@nomail> wrote in message 
news:web.49052186d757dcd7892adb1d0@news.povray.org...
>
> So far, Bob got the idea of what I was looking for, but I still have one
> concern.

Well, Chris was onto something good there first. And when I saw Mike's image 
map idea that seemed easiest, I'm just not sure if a single image with 
horizontal lines can be changed (increasing/decreasing number of wedges) 
within POV alone by scaling for example since I also can't remember that 
about map_type 5.

> I want to control how many sections there are, it seems to be related to
> "radial frequency 30" and maybe the number of entries in the color_map.
>
> Any suggestions on understanding this?

That's part of what confused me. I must admit I haven't used the toroidal 
warp in what's probably been years. Maybe never with radial pattern. I 
thought it would take one slice of radial pattern and wrap it using the 
exact number of iterations from frequency. Of course, I could still be doing 
something wrong.

> FYI,
> I want to make some areas of the cross-section transparent (hence the 
> rgbt).
>
> I want to be able to animate the rotation of the colors around the 
> section. That
> seems controllable e.g. "rotate x * frame_number"

You have the right iea there, I believe, yes. Although, a quick check on 
that shows once again something isn't right about my using frequency 30 to 
get the much fewer wedges than expected and how it rotates. For instance, 
using rotate x*48*clock with that and your color_map seems to complete 
approx. one revolution, so the usual x*360*clock is far too much (360 being 
degrees, of course) instead of going one time around. Due to the multiples 
caused by 30 in frequency, perhaps, yet that still doesn't match up. A 
frequency 1 and a color map list of a specific number of entries seems to 
not be right either for whatever reason.

So unless something can be done about figuring the correct way to get a 
singular radial pattern mapped into the torus it won't be simple to animate. 
Which is why I'm thinking Mike has the best solution using image_map and 
map_type 5, if you just give it a palletted image to work with the colors 
and transparency.

But I can't help wonder what's going on with radial pattern being warp'd and 
not adhereing to its original pattern, distorting in a somewhat non-toroidal 
way or imperfectly anyhow. Maybe...

> Fwiw Here's my version based on Bob's code:

See previous message...


-- 
/*bob hughes*/

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