POV-Ray : Newsgroups : povray.binaries.images : A radial pattern contains randomize(bump) : Re: A radial pattern contains randomize(bump) Server Time22 Sep 2023 03:30:27 EDT (-0400)
 Re: A radial pattern contains randomize(bump)
 From: And Date: 28 Aug 2023 12:05:00 Message:
"Bald Eagle" <cre### [at] netscapenet> wrote:
>
> Hi And,
>
> These are interesting pattern experiments, and I'm looking forward to seeing
> what you come up with.
>
> I find it interesting to see the pattern that you have here, as I didn't
> understand how the effect was being generated from a circular base pattern.
>
> I coded your pattern into a scene, and for some reason, did not get the same
> result.  Perhaps you could post the full code of a working scene.
>
> Also, if you could describe the exact type of pattern that you are looking to
> make, it would be easier to help you develop something through a logical
> elaboration of a base pattern function.
>
> I started with an atan2 (x, y) function, as that will give you a radial pattern
>
> #version 3.8;
> global_settings {assumed_gamma 1.0}
> default {finish {diffuse 1}}
>
> #include "functions.inc"
>
> camera {
>  location <0, 0, -10>
>  right     x*image_width/image_height
>  up y
>  look_at <0, 0, 0>
>
> }
>
> light_source {<0,  1, -50> rgb 1.0}
> sky_sphere {pigment {rgb 1}}
>
>
> #declare C = function {0.5 - sqrt (x*x+y*y) + 0.1}
>
> #declare W1 = function {f_bumps (x/C(x, y, z), y/C(x, y, z), z)}
>
> #declare Freq = 20;
> #declare Ang = function {atan2 (x, y)/(tau/Freq)}
>
> #declare W2 = function {f_bumps (Ang (x, y, z), Ang (x, y, z), z)}
>
> #declare Wood1 =
> color_map {
>  [0.00 srgb <249, 210, 173>/255]
>  //[0.25 srgb <249, 210, 173>/255]
>
>  [0.25 srgb <252, 156, 173>/255]
>  //[0.50 srgb <252, 156, 173>/255]
>
>  [0.50 srgb <206, 126,  72>/255]
>  //[0.75 srgb <206, 126,  72>/255]
>
>  [0.75 srgb <113,  51,  24>/255]
>  //[1.00 srgb <113,  51,  24>/255]
>
> }
>
> plane {z, 0 pigment {function {W1(x, y, z)} color_map {Wood1}} }
>
> //plane {z, 0 pigment {function {W2(x, y, z)} color_map {Wood1}} }
>
> Attached is what I get when I try to use the functions posted here.

Very beautiful image.
I use
camera{
location <0, 0, 10.4>
look_at <0.0, 0.0, 0.0>
right -x*image_width/image_height
sky <0,0,1>
angle 48
}

as my camera.