POV-Ray : Newsgroups : povray.advanced-users : Grid artifact in f_noise3d isosurface : Re: Grid artifact in f_noise3d isosurface Server Time
26 Jun 2024 03:41:23 EDT (-0400)
  Re: Grid artifact in f_noise3d isosurface  
From: Klaus Lehtonen
Date: 2 Jul 2002 15:47:57
Message: <3d22036d@news.povray.org>
From: "Slime"
> At first I was a bit annoyed by this, but having looked at the 3.1 source
in
> the past, I know that it's caused by the way the noise functions are
> created. They are *based* on a grid pattern of random values, which are
> interpolated between. I'm not sure exactly how the new noise generator
> works, but since it shows the same artifact, I assume it's similar.

Is the interpolation cubic like in sp_lines or cosine based? (
http://freespace.virgin.net/hugo.elias/models/m_perlin.htm has decription of
the funtions that I'm writing) I tried to look at the source myself but my C
skills are pretty bad. If it is cosine based the grid could be natural part
of the function. I'm thinking this because the small lines that cause the
grid are visible even when using one dimentional version of the function.
(just change f_noise3d(x,y,z) to f_noise3d(x,0,0) ) Sorry if this is too
newbie question for advanced-users.

Klaus Lehtonen


Post a reply to this message

Copyright 2003-2023 Persistence of Vision Raytracer Pty. Ltd.