Combine overlay graphics in draw

[glv]

This may be simpler and does not use PGraphics; I did something similar with a PGraphics object.

1. Generate an array of 1000 stars in setup(),
2. Display stars in draw() and update number of stars to display (from 0 to 999) every 2 seconds (120 frames).

float [][] stars;
int count = 0;

void setup()
  {
  size(500, 500);  
  stars = new float [1000][3];
  for (int i = 0; i<1000; i++)
    {
    stars[i][0]  = ?;          // random x
    stars[i][1] =  ?;          // random y
    stars[i][2] =  ?;          // random strokeWeight
    }
  }

void draw()
  {
  background(0);
  
  if (frameCount%120==0)              //every 2 seconds
    count++;
  starfield2(count);
  if (count>=999) count = 999;  
  }

void starfield2(int starCount)
  {
  stroke(255);
  for (int i = 0; i<starCount; i++)
    {
    ?  //strokeweight from array
    ?  // point from array
    }
  }