         pos
       //)
       ,
-      vec3(2.0, 2.0, 2.0)
+      vec3(2.)
     ),
     0.1), 0.0
   );

    lin += .4*amb*vec3(.4,.6,1.)*occ;
    lin += .5*dom*vec3(.4,.6,1.)*occ;
    lin += .5*bac*vec3(.25,.25,.25)*occ;
    lin += .25*fre*vec3(1.,1.,1.)*occ;
    col = col*lin;

    col = mix( col, vec3(.8,.9,1.), 1.-exp( -.0002*t*t*t ) );

  return vec2(sdBloodCell(
    opRep(
      pos,
      vec3(1.)
    ),
    // TODO: tweak parameters
    vec3(-.15, 1.275, -.001)
