ref: 2522dd249bc30472a8a9a1ae12286cba6542ba9c
dir: /html/loopy.html/
Loopy <p> Form a single closed loop out of the grid edges, in such a way that every numbered square has exactly that many of its edges included in the loop. <p> Click on a grid edge to mark it as part of the loop (black), and again to return to marking it as undecided (yellow). Right-click on a grid edge to mark it as definitely not part of the loop (faint grey), and again to mark it as undecided again. <p> When you have mastered the square grid, look in the Type menu for many other types of tiling!