Perlin Noise demonstration

int numParticlesPerRow = 40;

int numParticles = numParticlesPerRow * numParticlesPerRow;

color[] colors = new color[numParticles];

​

void setup()

{

  size(500, 500);

  for (int i=0; i<numParticles; i++)

  {

    colors[i] = color(random(100,150), random(20, 40), random(100,150), random(50,120));

  }

}

​

void draw()

{

  background(255);

  noStroke();

  int particleNumber = 0;

  for (int i=0; i<numParticlesPerRow; i++)

  {

    for (int j=0; j<numParticlesPerRow; j++)

    {

      fill(colors[particleNumber]);

      float x = float(i)/numParticlesPerRow * width;

      float y = float(j)/numParticlesPerRow * height;

      float scale = 0.07 * float(mouseX) / width;

      float speed = float(mouseY) / height;

      x = x + noise(x*scale, y*scale, frameCount*speed*0.021+1)*40;

      y = y + noise(x*scale, y*scale, frameCount*speed*0.02+2)*40;

      float size = noise(x*scale, y*scale, frameCount*speed*0.022)*25;

      ellipse(x, y, size, size);

      particleNumber++;

    }

  }

}