String[] data;
int res;

void setup() {
  size(400, 400);
  res = min(width, height)/8;
  data = loadStrings("data.txt");
}

void draw() {
  background(255);
  noStroke();
  for (int q = 0; q < 4; q++) {
    String[] quad = split(data[q], " ");
    int i = 0;
    for (String d : quad) {
      int val = int(d);
      fill(val);
      int x = i%4 + (q==1||q==3?4:0);
      int y = i/4 + (q==2||q==3?4:0);
      rect(x*res, y*res, res, res);
      i++;
    }
  }
}