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Image generated using POV-Ray for Windows 3.6; resulting slides were converted to an animated GIF using GIMP 2.3.6.

//------------------------------------------------------------
// Copyright 2006 DavidHOzAu
//------------------------------------------------------------
// This work is licensed under the Creative Commons Attribution ShareAlike License. 
// To view a copy of this license, visit http://creativecommons.org/licenses/by-sa/2.5/ 
//------------------------------------------------------------

#include "colors.inc"
#include "textures.inc"
#include "metals.inc"
#include "stones.inc"
#include "golds.inc"

global_settings {
  photons {
    count 2000
    autostop 0.5
    jitter .4
  }
  radiosity {
    normal on
    count 100
    recursion_limit 5
    error_bound 1
    low_error_factor 1
    brightness 1.5
  }
  ambient_light rgb 1/3
}

#declare seer = <4, 4, -9>;

camera {
        location  seer
        up <0, 1, 0>
        right <4/3, 0, 0>
        angle 34
        look_at   <0.75, 0.5, 0>
}     

light_source {
  <13, 13, -5>
  color rgb <1.4, 1.3, 1.2>
  fade_distance 15
  fade_power 2
  photons {
     refraction off
     reflection on
  }
  
  area_light <.4, 0, 0>, <0, 0, .4>, 5, 5
}

light_source {
  <20, 0, -5>
  color rgb 1
  fade_distance 15
  fade_power 2
  photons {
     refraction off
     reflection on
  }
  area_light <.4, 0, 0>, <0, 0, .4>, 5, 5
  shadowless
}

light_source {
  seer
  color rgb 1
  fade_distance 2
  fade_power 2
  photons {
     refraction off
     reflection on
  }
  shadowless
}

background {
  color 0
}

#declare MarbleFloorTex1 = texture {
  T_Grnt9
  finish {
    reflection 0.25
    ambient rgb 0.5
  }
  scale 10      
}
    
#declare MarbleFloorTex2 = texture {
  T_Stone10//T_Stone17
  //pigment { color Gray75 }
  finish {
    reflection 0.25
    ambient rgb 0.5
  }
  scale 10
}

// FloorBuilder
#macro FloorBuilder (vc, dm, nmx, nmz, sc, of)
  #local ix = 0;
  #while (ix < nmx)
    #local iz = 0;
    #while (iz < nmz)
      box {
          <ix*dm, -0.1, iz*dm>
          <(ix+1)*dm, 0, (iz+1)*dm>
          #if (mod(ix + iz, 2) = 0)
            texture {
              MarbleFloorTex1
              scale sc
              translate <of*ix*sc*dm, 0, of*iz*sc*dm>                            
            }
          #else
            texture {
              MarbleFloorTex2
              scale sc
              translate <of*ix*sc*dm, 0, of*iz*sc*dm>
            }
          #end
          translate <-nmx*dm/2, 0, -nmz*dm/2>
          translate vc
          photons {
             target
          }
      }
      #local iz = iz + 1;
      #end
    #local ix = ix + 1;
  #end
#end

FloorBuilder(<0, -10, 0>, 10, 100, 100, 15, 2)    

// Classic-style ring is an intersection of three torus
#macro SonicRing(d, r, f) 
  intersection {
    object {
      torus {
        d + (r*f*sqrt(3)/2), r
        sturm
      }
      translate -y*r*f/2
    } 
    object {
      torus {
        d + (r*f*sqrt(3)/2), r
        sturm
      }
      translate y*r*f/2
    }  
    object {
      torus {
        d-(r*f), r
        sturm
      }
    }
    rotate 90*z
  }
#end

#macro SonicRingRotate(d, r, f, a)
merge{
  SonicRing(d, r, f)
  scale 0.5
  rotate 180*y*(clock+a)
#end

#macro GlowRing(d, r, f, a, tr)
#local sinmul = 1/8*pow(f-sqrt(-3*pow(f,2)+4),2)*sqrt(3);
#local cosmul = sqrt(1 - pow(sinmul,2));
  object {
     SonicRingRotate(d, r, f, a)
    texture { 
       pigment {
         color <1.00, 1.0, 0.5>
       }
       finish {
         ambient <0.4, 0.3, 0.2>
       }
    }
    photons {
       target
       reflection on
    }
    translate tr
    
  }
#end

// Three rings in a row
GlowRing(2, 1, 0.25, 0.0, 0)
GlowRing(2, 1, 0.25, 0.0, <0, 0, 4>)
GlowRing(2, 1, 0.25, 0.0, <0, 0, 8>)

Final_Frame=9
Cyclic_Animation=on
Input_File_Name=ring.pov