POV-Ray : Newsgroups : povray.newusers : Normal problems - waves too 'flat' : Re: Normal problems - waves too 'flat' Server Time
30 Jul 2024 10:24:03 EDT (-0400)
  Re: Normal problems - waves too 'flat'  
From: Hughes, B 
Date: 2 Jul 2004 00:24:43
Message: <40e4e38b$1@news.povray.org>
"David Karl" <dka### [at] asninccom> wrote in message
news:40e484b6$1@news.povray.org...
> Hi all!

Hello there!  :-)

8<----
> This is the first hurdle I haven't been able to get around.  Something
> changed with normals between 3.1 and 3.5, and it's really screwing around
> with the one texture I've got.  This is from an awesome Mike Miller scene
> file (kudos to those who can figure out which one!).  The code below is
just
> from the simple boilerplate scene with some extra stuff removed (I'd post
> links to images but my webserver no likey me at the moment).  Render it
with
> the version directive intact and you'll see what I *want* to get...  A
> sphere, with some gentle, um, horizontal ripples (latitudinal?  whatever).
> You can see the crests and troughs without a problem, and the phong
> highlight is nicely distributed just as you'd expect it to be.
>
> Now render it without the version override.  Or, for sake of argument,
with
> #version 3.5; you'll see the difference immediately.  The normal appears
to
> flatten out, resulting in ugly green and black(ish) bands without any
> highlight left.
----8<

Um... hmmmmm. No idea why that is, but your message here got me to trying
number_of_waves and I'm seeing once again what might have been a bug during
beta testing, which could be totally unrelated. However, then again it could
be related in at least some obscure way I guess. Unfortunately, I don't
recall what, if anything might have been done about it. I was a little
sparse on beta testing toward the end.

For instance: if global_settings {number_of_waves 10}} is used (the default)
I get a different (and incorrect) rendering from the next, or following,
render without changing its value. To see this happen yourself you'll need
to set another value, render, then change it to 10, render, and finally
render one last time after that. Take note of the appearance of the sphere
when 10 is used the first time. Of course, it might not happen for everyone.

Bob H.


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