Can you explain how the automatic element placement system in Auto Layout is implemented at the internal mechanics level?

The automatic element placement system in Auto Layout is based on constraints, which define rules for the positioning and sizing of interface elements.

Internally, Auto Layout constructs a system of equations based on the specified constraints (such as distances between elements, proportions, alignment). Then, using a linear equation solving algorithm (usually Cramer's rule or the simplex method), the exact positions and sizes of all elements are calculated.

Thus, when the screen size or content changes, the system automatically recalculates and updates the element positions, providing a responsive and predictable interface without manual positioning.