Quick & Dirty screensaver for PyCon.

gistfile1.java

import processing.opengl.*;

void setup()
{
  size(1440, 960, OPENGL);
  background(0);

} 

void star(int size)
{
  pushMatrix();
  beginShape(LINES);
  vertex(-size, -size, 0);
  vertex(size, size, 0);
  vertex(size, -size, 0);
  vertex(-size, size, 0);
  endShape();
  popMatrix();
}

color colors[] = {
  color(0x55ffff, 0xff), 
  color(0x55ff55, 0xff), 
  color(0xffff55, 0xff),
  color(0xff55ff, 0xff)
};

void generate() 
{
  for(int i=0;i<N;i++) {
    if(stars[i] == null || stars[i].y < frameCount) {
      stars[i] = new PVector(random(0, frameCount + width), random(0, frameCount + height), random(0, 500));
      starColors[i] = colors[ (int)random(colors.length) ];
      starSizes[i] = (int)random(1, 7);
    }
  }
}

int N = 100;
PVector[] stars = new PVector[N];
color[] starColors = new color[N];
int[] starSizes = new int[N];


// Available from https://github.com/python-finland/fi.pycon.org/blob/master/media/2011/site/logo.png
PImage logo = loadImage("logo.png");

void draw() 
{
  generate();
  background(0);
  
  pushMatrix();
  translate(0, -frameCount);
  for(int i=0;i<N;i++) {
    pushMatrix();
    stroke(starColors[i]);
    translate(stars[i].x, stars[i].y, stars[i].z);
    star(starSizes[i]);
    popMatrix();
  }
  popMatrix();

  translate(width/2, height/2 + sin(radians(frameCount)) * 50 );
  image(logo, -logo.width / 2, -logo.height / 2);
}