void setup () {
size (580,870);
background (0);
noStroke ();
smooth();
frameRate (10);
}

void draw () {
  PFont font;
font = loadFont ("Annifont-20.vlw");
textFont(font);
fill(255);
text ("Shibuya st. 109",310,788);

float a=map( mouseX,20,width,0.1,20);
  for (int i=85; i<=500; i+=40) {
    for (int j=85; j<=725; j+=30) {
      fill(random(255),random(255),random(255),random(255));
      rect (i,j,a,a);
    }
  }
}