Animated Rossler Attractor

mySketch
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var dots = 1000;
var x = new Array(dots);
var y = new Array(dots);
var z = new Array(dots);
var nx = new Array(dots);
var ny = new Array(dots);
var nz = new Array(dots);
var px = new Array(dots);
var py = new Array(dots);
var pz = new Array(dots);
var dt = 0.01;
var r = 33;
var l = 0;
var s = 1;
var per = "xz";
var a = 0.2, b = 0.2, c = 5.7;
​
function setup() {
  createCanvas(800, 800);
  background(255);
  
  for (i = 0; i < dots; i++) {
    x[i] = (random(-4, 4));
    y[i] = (random(-3, 5));
    z[i] = (random(-3, 5));
  }
}
​
function draw() { 
  if (l === 0) {
    background(255);
  }
  
  if (s === 0) {
    strokeWeight(1);
  }
  
  for (i = 0; i < dots; i++) {
    px[i] = x[i];
    py[i] = y[i];
    pz[i] = z[i];
    
    nx[i] = -y[i] - z[i];
    ny[i] = x[i] + a*y[i];
    nz[i] = b + z[i]*(x[i] - c);
    
    x[i] += nx[i]*dt;
    y[i] += ny[i]*dt;
    z[i] += nz[i]*dt;
    
    if (s === 1) {
      if (per === "xy") {
        strokeWeight(map(z[i], -r/3, r/3, 2, 3));
      } else if (per === "xz") {
        strokeWeight(map(y[i], -r/3, r/3, 3, 2));
      } else {
        strokeWeight(map(x[i], -r/3, r/3, 2, 3));
      }
    }
    
    if (l === 0) {
      if (per === "xy") {
        point(map(x[i], -r, r, 0, width), map(y[i], -r, r, height, 0));
      } else if (per === "xz") {
        point(map(x[i], -r, r, 0, width), map(z[i]-28, -r, r, height, 0));
      } else {
        point(map(y[i], -r, r, 0, width), map(z[i]-28, -r, r, height, 0));
      }
    } else {
      stroke(0, 2000/dots);
      
      if (per === "xy") {
        line(map(px[i], -r, r, 0, width), map(py[i], -r, r, height, 0), map(x[i], -r, r, 0, width), map(y[i], -r, r, height, 0));
      } else if (per === "xz") {
        line(map(px[i], -r, r, 0, width), map(pz[i]-28, -r, r, height, 0), map(x[i], -r, r, 0, width), map(z[i]-28, -r, r, height, 0));
      } else {
        line(map(py[i], -r, r, 0, width), map(pz[i]-28, -r, r, height, 0), map(y[i], -r, r, 0, width), map(z[i]-28, -r, r, height, 0));
      }
    }
  }
}