//-------------------------------------------------------------------------------------------------
//-------------------------------------------------------------------------------------------------
#declare Pigment_1 = 
   pigment {
      marble
      turbulence <0.1,0,0>
      translate <-0.5,0,0>
      scale <0.025,1,1>
      rotate <0,0,90>
      warp {repeat 0.5*x flip x}
      warp {repeat 0.5*y flip y}
      colour_map {
         [0, rgbf <0.86,0.86,0.86,0.6>] //<0,0,0,0>]
         [1, rgbf <1,1,1,0.6>]
      }
  translate<0,0.5,0>
 } // end pigment

#declare Marb= function {
  pigment {    
     Pigment_1  
  } // end pigment
}
#declare R= function(u,v) {
  -Marb(u,v,0).gray *1.05
}
 
//-------------------------------------------------------------------------------------------------
//-------------------------------------------------------------------------------------------------
#declare a=0.3; #declare b=1; 
#declare c=0.2; #declare n=3;
#declare F1= function(u,v){R(u,v)*((a*(1-v/(2*pi))*cos(n*v)*(1+cos(u))+c*cos(n*v)))} 
#declare F2= function(u,v){R(u,v)*((a*(1-v/(2*pi))*sin(n*v)*(1+cos(u))+c*sin(n*v)))} 
#declare F3= function(u,v){(b*v/(2*pi)+a*(1-v/(2*pi))*sin(u))}
//-------------------------------------------------------------------------------------------------
#include "meshmaker.inc"
//-------------------------------------------------------------------------------------------------
object{ // Parametric(Fx,Fy, Fz, <UVmin>, <UVmax>, Iter_U, Iter_V, FileName)
   Parametric( // Builds a parametric surface out of three given functions. 
               // The uv_coordinates for texturing the surface come from the square <0,0> - <1,1>. 
      F1, F2, F3, //three functions
     <0, 0>, <2*pi, ToV(2*pi)>,// range within to calculate surface: <u min, v min>,<u max, v max>. 
      50,100, // resolution of the mesh in the u range and v range.
       "" // FileName: ""= non, "NAME.obj'= Wavefront objectfile, "NAME.pcm" compressed mesh file 
          // "NAME.arr" = include file with arrays to build a mesh2 from, 
          //  others: includefile with a mesh2 object 
   ) //---------------------------------------------------------------------------------------------
 //  no_shadow
   texture {  // inside texture
     uv_mapping
     pigment{ color rgb <1,0.8,0.8> }  
//     pigment{ checker color rgb <0.5,0.0,0.1> rgb <1,1,1> scale <0.025,0.0035,0.01>}
     finish { specular 0.15}
   } // 
   interior_texture{            //  outside texture
    // uv_mapping
     pigment{  color rgb<1,1,1>}  //0.9, 0.85, 0.75>*0.95}
     //normal { bumps 0.25 scale 0.0025 }
     finish { phong 0.5}
/*     uv_mapping
     pigment{ checker color rgb <0.0,0,0.0> rgb <1,0.9,0.9>  scale <0.05,0.0065,1>}
     finish { phong 0.5 }
*/
   } // 
   
   rotate<-90,0,0>
   scale<-1,1,1>*1.9
   translate< 0, 0, 0 >
} // end of object 
//---------------------------------------------------------------------------------------------------
//---------------------------------------------------------------------------------------------------