blob28

  # name of the blob
  project = "blob28";
   
  function w = f(x2,y2,z2,c,r,e) 
   x  = (x2-c(1))/r(1);
   y  = (y2-c(2))/r(2);
   z  = (z2-c(3))/r(3);
   # function at origin must be <0, and >0 far enough away.  w=0 defines the surface
   k = -0.5;
   j = -15;
   theta = atan2(x,y);

   w = ((0.3*x).^2 + (0.3*y + 0.0*(z).*(z - 1)).^2 + (z.^2));
   w = w + 2./((0.8*x - 0.5).^2 + (y - 0.0).^2 + (z - 0).^2);
   w = w - (0.3)./((x - 2).^2 + (y - 2).^2 + 8*z.^4);
   w = w - (0.3)./((x - 2).^2 + (y + 2).^2 + 8*z.^4);
   w = w-1;

   endfunction;

  c_outer = [0,0,0];
  r_outer = [30,30,30]; 

  step = 4;  # grid pitch in mm  start with 4mm to see the shape quickly.  Once you have it just right, change to 2mm for printing

  source("../octave/func2stl_v01.m");  # do all the calculations