Processing2.0b8 new function sample Lite version is https://gist.github.com/p5info/5027951

Sample2.0b8.pde

final int RATIO = 10;
float x, y;
PGraphics g1, g2;
int SIDE=200;
int WIDTH=SIDE*2, HEIGHT=SIDE;

void setup() {
  frameRate(1000);
  clear();//more than 2.0b8 (If less than 2.0b7 background(0, 0, 0, 0))
  size(WIDTH, HEIGHT);
  stroke(255);

  g1 = createGraphics(SIDE, SIDE);
  g1.beginDraw();
  g1.clear();//more than 2.0b8 (If less than 2.0b7 background(0, 0, 0, 0))
  g1.stroke(255);
  g1.endDraw();

  g2 = createGraphics(SIDE, SIDE);
  g2.beginDraw();
  g2.clear();//more than 2.0b8 (If less than 2.0b7 background(0, 0, 0, 0))
  g2.stroke(255);
  g2.endDraw();
}
void draw() {
  g1.beginDraw();
  x =g1.width/2+ random(-1, 1)*RATIO;
  y =g1.height/2+ random(-1, 1)*RATIO;
  g1.point(x, y);
  g1.endDraw();
  image(g1, 0, 0);

  g2.beginDraw();
  x =g2.width/2+ randomGaussian()*RATIO;//more than 2.0b8
  y =g2.height/2+ randomGaussian()*RATIO;//more than 2.0b8
  g2.point(x, y);
  g2.endDraw();
  image(g2, width/2, 0);

  line(width/2, 0, width/2, height);
}