gistfile1.txt

import processing.pdf.*;

boolean recordFrame = false;

float x;
float diameter;

void setup() {
  size(400, 600);
  x = random(0, width);
  diameter = random(10, 30);
}

void draw() {
  if (recordFrame == true) {
    beginRecord(PDF, "FourCircles-" + nf(frameCount, 3) + ".pdf");
  }

  background(204);
  fill(0);  
  ellipse(x, 300, diameter, diameter);
  ellipse(x, 320, diameter, diameter);
  ellipse(x, 340, diameter, diameter);
  ellipse(x, 360, diameter, diameter);

  if (recordFrame == true) {
    endRecord();
    recordFrame = false;
  }
}

void keyPressed() {
  if (key == ' ') {
    x = random(0, width);
    diameter = random(10, 30);
  }
  if (key == 'r' || key == 'R') {
    recordFrame = true;
  }
}