float x1, y1, x2, y2; 

float t = 0.0;
float increment = 0.01; // 0.1

void setup() {
  size(500, 500);
  x1 = (noise(t)) * width;
  y1 =(noise(t + 100)) * height;
}

void draw() {
  x2 = (noise(t)) * width;
  y2 = (noise(t + 100)) * height;

  line(x1, y1, x2, y2);

  x1 = x2;
  y1 = y2;

  t += increment;
}