positioning.js

var r = new Rune({
  container: "#canvas",
  width: 800,
  height: 550,
  debug: true
});

var bigSize = 300;
var bigX = (r.width/2) - (bigSize/2);
var bigY = (r.height/2) - (bigSize/2);

var smallSize = 100;
var smallX = (r.width/2) + (bigSize/2) - (smallSize/2);
var smallY = (r.height/2) + (bigSize/2) - (smallSize/2);

r.rect(bigX, bigY, bigSize, bigSize);
r.rect(smallX, smallY, smallSize, smallSize)
  .rotate(45, smallX + (smallSize/2), smallY + (smallSize/2));

r.draw();