斜め交互タイル

/**
* skew alternate tiling
*
* @author aa_debdeb
* @date 2016/06/21
*/


float e = 20;
float theta = PI / 4;
float margin = 50;

void setup(){
  size(500, 500); 
  mousePressed();
}

void draw(){

}

void mousePressed(){
  fill(random(255), random(255), random(255));
  stroke(random(255), random(255), random(255));
  strokeWeight(5);

  boolean isToRight = true;
  float h = -margin;
  while(h < height + margin){
    for(float w = -margin; w < width + margin; w += e * 2 / sqrt(2)){
      pushMatrix();
      if(isToRight){
        translate(w, h);
        rotate(theta);
      } else {
        translate(w + e / sqrt(2), h);
        rotate(theta + PI / 2);      
      }
      rect(0, 0, 2 * e, e);      
      popMatrix();
    }
    h += isToRight ? e * 3 / sqrt(2): e / sqrt(2);
    isToRight = !isToRight;
  }
}