float [] xp = new float[0];
  float [] yp = new float[0];
  int numObjects = 0;
  int tol2 = 15;
  void setup(){
    size(300,300);
     xp = append(xp,random(10,width-10));
     yp = append(yp,random(10,height-10));
  }
  void draw(){
    background(255);
    for(int i=0; i<xp.length; i++)
      rect(xp[i],yp[i],10,10);
  }
  void keyPressed(){
    int k = 0;
    while(true){
      boolean overlap = false;
      float xrand = random(xp[xp.length-1]-tol2,xp[xp.length-1]+tol2);
      float yrand = random(yp[yp.length-1]-tol2,yp[yp.length-1]+tol2);
      for(int j=0; j<xp.length; j++){
        float distance = dist(xrand,yrand,xp[j],yp[j]);
        if(distance < 10 || xrand>width-10 || xrand<1 || yrand >height-10 || yrand<1) overlap = true;
      }
      if(overlap==false){
        xp = append(xp,xrand);
        yp = append(yp,yrand);
        tol2 = 15;
        break; 
      }
      k++;
      if(k>1000){
        //println(xp.length + " impass"); 
        tol2+=10;
        break;
      }
    }
    //println(numObjects++);
    //save("stoch"+nf(numObjects,2)+".jpg");
  }