float increment = 0.01;
  // The noise function's 3rd argument, a global variable that increments once per cycle
  float zoff = 0.0;  
  // We will increment zoff differently than xoff and yoff
  float zincrement = 0.02; 
  
  void setup() {
    size(200,200);
    frameRate(30);
  }
  
  void draw() {
    background(0);
    
    // Optional: adjust noise detail here
    // noiseDetail(8,0.65f);
    
    loadPixels();
  
    float xoff = 0.0; // Start xoff at 0
    
    // For every x,y coordinate in a 2D space, calculate a noise value and produce a brightness value
    for (int x = 0; x < width; x++) {
      xoff += increment;   // Increment xoff 
      float yoff = 0.0;   // For every xoff, start yoff at 0
      for (int y = 0; y < height; y++) {
        yoff += increment; // Increment yoff
        
        // Calculate noise and scale by 255
        float bright = noise(xoff,yoff,zoff)*255;
  
        // Try using this line instead
        //float bright = random(0,255);
        
        // Set each pixel onscreen to a grayscale value
        pixels[x+y*width] = color(bright,bright,bright);
      }
    }
    updatePixels();
    
    zoff += zincrement; // Increment zoff
    
    
  }