int numBlobs = 3;
  
  int[] blogPx = { 0, 90, 90 };
  int[] blogPy = { 0, 120, 45 };
  
  // Movement vector for each blob
  int[] blogDx = { 1, 1, 1 };
  int[] blogDy = { 1, 1, 1 };
  
  PGraphics pg;
  int[][] vy,vx; 
  
  void setup() {
    size(640, 360);
    pg = createGraphics(160, 90, P2D);    
    vy = new int[numBlobs][pg.height];
    vx = new int[numBlobs][pg.width];
  }
  
  void draw() {
    for (int i=0; i<numBlobs; ++i) {
      blogPx[i]+=blogDx[i];
      blogPy[i]+=blogDy[i];
  
      // bounce across screen
      if (blogPx[i] < 0) {
        blogDx[i] = 1;
      }
      if (blogPx[i] > pg.width) {
        blogDx[i] = -1;
      }
      if (blogPy[i] < 0) {
        blogDy[i] = 1;
      }
      if (blogPy[i] > pg.height) {
        blogDy[i]=-1;
      }
  
      for (int x = 0; x < pg.width; x++) {
        vx[i][x] = int(sq(blogPx[i]-x));
      }
  
      for (int y = 0; y < pg.height; y++) {
        vy[i][y] = int(sq(blogPy[i]-y)); 
      }
    }
  
    // Output into a buffered image for reuse
    pg.beginDraw();
    pg.loadPixels();
    for (int y = 0; y < pg.height; y++) {
      for (int x = 0; x < pg.width; x++) {
        int m = 1;
        for (int i = 0; i < numBlobs; i++) {
          // Increase this number to make your blobs bigger
          m += 60000/(vy[i][y] + vx[i][x]+1);
        }
        pg.pixels[x+y*pg.width] = color(0, m+x, (x+m+y)/2);
      }
    }
    pg.updatePixels();
    pg.endDraw();
  
    // Display the results
    image(pg, 0, 0, width, height); 
  }