POV-Ray : Newsgroups : povray.general : Smooth level for smooth_triangle. : Re: Smooth level for smooth_triangle. Server Time
1 Mar 2024 18:54:56 EST (-0500)
  Re: Smooth level for smooth_triangle.  
From: GioSeregni
Date: 25 Nov 2023 12:45:00
Message: <web.656231a884c692a3276109cb59126100@news.povray.org>
"GioSeregni" <gms### [at] hotmailcom> wrote:
> "Kenneth" <kdw### [at] gmailcom> wrote:
> > "GioSeregni" <gms### [at] hotmailcom> wrote:
> > > "Bald Eagle" <cre### [at] netscapenet> wrote:
> > > >
> > > > And if you DO see red there, then try moving the camera around, and viewing it
> > > > from different angles - because it may just disappear and pop up in different
> > > > areas.
> > >
> > > It seems that they always arise on the
> > > perimeter of the volumes (in positions tangential to the cone of vision)...
> >
> > Yes, that is where those artifacts sometimes appear on a smooth-triangle object.
> > I think it also depends on the lighting angle, and maybe even the size of the
> > triangles.
> >
> > What you are seeing is a known effect of raytracing the smooth normals when they
> > are viewed at that raking angle. (I thought that there was a short technical
> > explanation of this in the documentation, but I cannot find it.) The camera is
> > picking up the unlighted (black) interior of the object.
> >
> > If I make a low-rez height_field and add the 'smooth' keyword, the same thing
> > happens. The interior_texture trick is one way to try and make these artifacts
> > less noticable. Or try adding the 'double_illuminate' keyword to the object. If
> > I recall, this was a recommended 'fix' for the problem. It seems to work most of
> > the time, but not in every situation.
>
> Ok, thank! I am working on .. it does not seems by light position, but by the
> angle between WP and smooth_triangle (s) ...
> Many thanks again!
> G.
Bug hacked?
old sprites concept? I'm under no illusions, I'll do more tests, but in this way
I don't see the bug anymore


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