Why won't my super formula code work?

I am currently using this video tutorial: to generate super shapes. I've checked my code over and over but still can't get it to generate the shapes outlined by the guide: http://paulbourke.net/geometry/supershape/ . I am struggling to see the flaw in my code as it looks identical to the tutorial? Any help is welcome. Thank you :)

import peasy.*;
import peasy.org.apache.commons.math.*;
import peasy.org.apache.commons.math.geometry.*;

PeasyCam cam;
PVector[][] globe;
int sum = 75;

void setup() {
  size(1900, 950, P3D);
  cam = new PeasyCam(this, 750);

  globe = new PVector[sum+1][sum+1];
}

float a = 1;
float b = 1;

float supershape(float theta, float m, float n1, float n2, float n3) {

  float t1 = abs((1/a)*cos(m*theta/4));
  t1 = pow(t1, n2);
  float t2 = abs((1/b)*sin(m*theta/4));
  t2 = pow(t2, n3);
  float t3 = t1 + t2;
  float r = pow(t3, -1/n1);

  return r;
}

void draw() {
  background(0);
  noStroke();
  lights();

  float r = 200;
  for (int i=0; i<sum+1; i++) {
    float lat = map(i, 0, sum, -HALF_PI, HALF_PI);

    float r2 = supershape(lat,
      8,
      60,
      100,
      30);


    for (int j=0; j<sum+1; j++) {
      float lon = map(j, 0, sum, -PI, PI);

      float r1 = supershape(lon,
      2,
      10,
      10,
      10);

      float x = r*r1*cos(lon)*r2*cos(lat);
      float y = r*r1*sin(lon)*r2*cos(lat);
      float z = r*r2*sin(lat);
      globe[i][j] = new PVector(x, y, z);
    }
  }

  stroke(255);
  fill(255);
  for (int i=0; i<sum; i++) {
    //ADD COLOUR HERE
    beginShape(TRIANGLE_STRIP);
    for (int j=0; j<sum+1; j++) {
      PVector v1 = globe[i][j];
      vertex(v1.x, v1.y, v1.z);
      PVector v2 = globe[i+1][j];
      vertex(v2.x, v2.y, v2.z);
    }
    endShape();
  }
}