The semi-squares can be ordered according to three different criteria: either by their left sides xi, or their y-coordinate of their basis at |Ii| - ⌊|Ii| * (1 - c)⌋ or by their hypotenuse. Hypotenuses can be easily ordered according to their height at a given x-position by noting that the slope is -1 for all of them. Thus, for every x-coordinate with x between xi and xi + ⌊|Ii| * (1 - c)⌋, the following equation is valid: