Spirals

class Spiral {

  constructor(A, B, C) {

    this.alpha=atan2(B.y-A.y, B.x-A.x);

    this.theta=4*TWO_PI+atan2(B.y-C.y, B.x-C.x);

    //this.v=PI+this.alpha-this.theta;

    this.b=exp(abs((B.x-A.x)/(B.y-A.y)));

    this.v=1/log(this.b);

    this.A = A;

    this.B = B;

    this.C = C;

    this.a=dist(B.x, B.y, C.x, C.y)/pow(this.b, this.theta);

  }

​

  display() {

    textSize(32);

    text("a: "+int(100*this.a)/100+" b: "+int(100*this.b)/100+" theta: "+int(100*this.theta)/100, 300, 300);

    let mx=this.B.x-this.C.x;//this.a * pow(this.b,this.theta)*cos(this.theta);

    let my = this.B.y-this.C.y;//this.a * pow(this.b, this.theta)*sin(this.theta);

    translate(this.C.x, this.C.y);

    ellipse(0, 0, 20, 20);

    for (let i = this.theta; i >=0; i-=.1) { 

      let xi = this.a * pow(this.b, i)*cos(i);

      let yi = this.a * pow(this.b, i)*sin(i);

      line(mx, my, xi, yi);

      mx=xi;

      my=yi;

    }

  }

}

​