isosurface { //------------------------------------------------------------- function{ f_helix2( // Needs a negated function x,y,z, 0, // not used, 4 * 2*pi,// For a number N of turns per 1 unit heigth(y) use: N*2*pi) 0.40*(1-y), // minor radius, (< or > major radius!) 0.05*(1-y/2), // major radius, 0, // not used, 1.0, // cross section type,( 1.0 = rounded ( sine shaped + profile // 2.0 = ?diamond? 0 // not used ? (without semicolon!) (? "cross section rotation angle") ) } threshold 0.0 contained_by {box {<-1,0,-1>,<1,1,1>}} max_gradient 34 texture{ pigment{ color rgb <0.8,0.5,0.6>*0.8 } // color rgb <1,1,1>} normal { radial frequency 36 scale 0.4 } finish { specular 0.1 roughness 0.005 phong 1 phong_size 20 reflection {0.45 metallic } } } rotate<0,0,0> scale <1,1,1> translate< 0,0.00, 0> } // end of isosurface -------------------------------------------------------