Rippled Round Transparent Box Shader

Hello there!

Just a little experiment:

shader MBox(
    int size = 1,
    output closure color CL = holdout()
){
    float Prender(point P){


        for(int i = 0; i <= size; i++) {
            P *= P+sin((i*0.03)*sin(P*0.3*length(P*0.02)*0.0251))*0.033;
            if(length(P) <= 0.2 && length(P) > 0.18 ) { 
                CL =  emission()*color(noise (P / 0.02),noise (P / 0.01),noise (P / 0.03))*1.3;
            }  
        }
        return 0.0;
    } 
    
    Prender(P);  
    return;
}

Desired effect:


Cheers!