float i,d=1.,g;vec3 P,Q;for(;i++<99.&&d>1e-4;g+=d){P=Q=normalize(vec3(FC.xy-r*.5,r.y))*g;P.xy*=rotate2D(P.z*.1);P.x+=sin(P.z+t);P=abs(P=abs(P=fract(P)-.5)-.1)-.01;d=max(dot(P,P.yzx),length(P.xy)-.1);}o.rgb+=(fwidth(i)*vec3(.95,.4,.2)*exp(-4.*fract(t*.5+Q.z*.05)*2.)+.15);