p213

// based upon:
// P_2_1_3_03.pde
//
// Generative Gestaltung, ISBN: 978-3-87439-759-9
// First Edition, Hermann Schmidt, Mainz, 2009
// Hartmut Bohnacker, Benedikt Gross, Julia Laub, Claudius Lazzeroni
// Copyright 2009 Hartmut Bohnacker, Benedikt Gross, Julia Laub, Claudius Lazzeroni
//
// http://www.generative-gestaltung.de


float tileCountX = 3;
float tileCountY = 3;
int count = 0;
float theta;

void setup() {
  size(400, 400);
}


void draw() {
  rectMode(CENTER);
  stroke(0,200);
  background(255);


  count = (int) map(sin(theta), -1, 1, 10, 15);
  float para = map(sin(theta), -1, 1, 0.1, 0.3);

  for (int gridY=0; gridY<= tileCountY; gridY++) {
    for (int gridX=0; gridX<= tileCountX; gridX++) {
      float tileWidth = width / tileCountX;
      float tileHeight = height / tileCountY;
      float posX = tileWidth*gridX + tileWidth/2;
      float posY = tileHeight*gridY + tileHeight/2;


      pushMatrix();
      translate(posX, posY);

      for (float i=0; i<=count; i++) {

        line(para*tileWidth, para*tileHeight, tileWidth/2, (i/count-0.5)*tileHeight);
        line(para*tileWidth, para*tileHeight, -tileWidth/2, (i/count-0.5)*tileHeight);
        line(para*tileWidth, para*tileHeight, (i/count-0.5)*tileWidth, tileHeight/2);
        line(para*tileWidth, para*tileHeight, (i/count-0.5)*tileWidth, -tileHeight/2);
      }
      popMatrix();
    }
  }
    theta += 0.0523*2;

  if (frameCount%4==0 && frameCount<61) saveFrame("image-####.gif");

}