float i,e,a,l,y;vec3 p,q,d=vec3((FC.xy-.5*r)/r.y,-1);for(d.xz*=rotate2D(t*.2);i++<2e2;e=max(min(++y,-e),y-3.)){i>1e2?l=log(e+=1e-4)/1e2,d/=d,o:o+=exp(-e*1e3)/2e2;p=q+=d*e*.7;p++;y=p.y;for(a=3.;a>.04;a*=.6)p.xz*=rotate2D(5.),p=abs(p)-a,e=min(e,max(p.x,(max(p.y,p.z))));}o+=l;