processing4/java/examples/Basics/Control/EmbeddedIteration/applet/EmbeddedIteration.java

import processing.core.*; 

import java.applet.*; 
import java.awt.*; 
import java.awt.image.*; 
import java.awt.event.*; 
import java.io.*; 
import java.net.*; 
import java.text.*; 
import java.util.*; 
import java.util.zip.*; 
import java.util.regex.*; 

public class EmbeddedIteration extends PApplet {
  public void setup() {/**
 * Embedding Iteration. 
 * 
 * Embedding "for" structures allows repetition in two dimensions. 
 */
 
float box_size = 11; 
float box_space = 12; 
int margin = 7; 
 
size(200, 200); 
background(0); 
noStroke(); 
 
// Draw gray boxes 
 
for (int i = margin; i < height-margin; i += box_space){
  if(box_size > 0){
    for(int j = margin; j < width-margin; j+= box_space){
      fill(255-box_size*10);
      rect(j, i, box_size, box_size);
    }
    box_size = box_size - 0.6f;
  }
}

		

  noLoop();
} 
  static public void main(String args[]) {
    PApplet.main(new String[] { "EmbeddedIteration" });
  }
}