// Note: this code is adapted from Reas and Fry, Processing
// This code draws an animated circle which moves down the screen.

float y = 0.0;
float yIncrement = 0.5;

void setup() {
  size(100,100);
  smooth();
  fill(0);
}

void draw() {
  background(204);
  ellipse(50, y, 70, 70);
  y += yIncrement;
}