On 6/5/25 20:21, Kenneth wrote:
> Hey, I think I solved these problems-- by using min (...).

Ah. Well done. :-) I believe in clamping the maximum value to <1.0 you 
are avoiding the pattern{} clamping / wrapping which otherwise occurs at 
values over >= approximately 1.0.

Where the f_torus() values would normally go to <0.0 at the surface the 
values are probably still getting wrapped to multiple roots. The 
clamping at <1.0 can also lead to complications should you end up 
combining FnTorusWarp() with other functions - including other 
placements of itself, depending of stuff. Lastly, in using the 0.01 
threshold, the surface (in cyan blue in the images) is at a slightly 
different position than the original f_torus() surface would have 
otherwise been.

Lets see... We can use yuqk to get a look at the original FnTorusWarp() 
values in the top row of the attached image using raw_wave over 
triangle_wave. In the middle row I commented raw_wave number 1 and 
uncommented your triangle wave (result matches v3.8 b2 in this case 
too). The bottom row of the image is your result in v3.8 b2 without 
either raw_wave, but the same defined -5 to +5 color_map{} - of which 
only 0-1 portion is used.

All that said, when getting a usable result for whatever the image's 
aims - it's all good, no matter the details! "If it sounds good, it is 
good" :-)

Bill P.

//---
#version 3.8;
#version unofficial 3.8; // yuqk
global_settings { assumed_gamma 1 }

#include "functions.inc"

#declare FnTorusWarp = function {
      pattern {
          function { f_torus(x,y,z, 8.0,2.5) }
        //raw_wave      //Number 1
          triangle_wave
          scale 2
          warp{ turbulence .5 omega .001 }
          scale 1/2
      }
}

plane { -z, 0
     pigment {
         function { FnTorusWarp(x,y,0) }
         raw_wave    // Number 2
         color_map {
         [-5.0  rgb <1,0,0>]
         [-1e-2 rgb <0,0,0>]
         [+1e-2 rgb <0,1,1>]
         [+2e-2 rgb <0,1,1>]
         [+3e-2 rgb <0,0,0>]
         [+5.0  rgb <0,1,0>]
         }
     }
     finish { emission 1 }
}
#declare Cam = camera {}
camera { Cam translate -20*z}
//---

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