title: Convert a rectangular grid of points into a hexagonal grid
body: <p>I have a rectangular grid of points like this<img src="https://i.stack.imgur.com/zEhMq.png" alt="enter image description here"> and I want to get indices of these points which forms a hexagonal grid like this <img src="https://i.stack.imgur.com/WT34G.png" alt="enter image description here">.</p>
  
  <p>How can I "Hexagonalize" the rectangular grid given that I want to draw only complete hexagons?  </p>
  
  <p>EDIT:</p>
  
  <p>I added another picture showing what I want to achieve <img src="https://i.stack.imgur.com/mnOh1.png" alt="enter image description here"></p>