/** 
floating particles by <a href="http://www.local-guru.net/">guru</a> 
*/

PVector particle[][];

void setup() {
  size(300,300);
  smooth();
  particle = new PVector[4][20];
  for( int j = 0; j<4; j++) {
    for (int i = 0; i<20; i++) {
      particle[j][i] = new PVector( random( width), random(height), random(10,20));
    }
  }
}

void draw() {
  background(0);
  for( int j = 0; j < 4; j++) {
  noStroke();

  for( int i = 0; i < 20; i++) {
    
    if ( j < 3 ) stroke(255, 100 + particle[j][i].z*4, 0,  255 );
    fill(255, 100 + particle[j][i].z*4, 0,  100 + i * 5);
    
    float r = particle[j][i].z;
    ellipse( particle[j][i].x,particle[j][i].y, r,r);    
    particle[j][i].add( new PVector( random(-j/2,j/2), random(-j/2,j/2),0));
  }
  if (j < 3) {
    filter(BLUR,2);
  }
  
  }
}