surface
candy_dots(float    Kfb = 1,
                    radius = 0.1,
                    s0 = 0.1,
                    t0 = 0.1,
                    gap_s = 0.3,
                    gap_t = 0.3;
            color    wrap_color = color(0.2, 0, 0.3),
                    dots_color = color(0.7, 0.2, 0);)
        
{
color    surfcolor = wrap_color;
  
float    i, k;
for(i = s0; i < 1 + radius; i += gap_s)
    for(k = t0; k <1 + radius; k += gap_t){
if(pow(s - i,2) + pow(t - k,2) <= pow(radius, 2))
    surfcolor = dots_color;
}
  
Oi = Os;
  
Ci = Oi * Cs * surfcolor * Kfb;
}